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Journal Cover The Knee
  [SJR: 1.236]   [H-I: 53]   [15 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0968-0160
   Published by Elsevier Homepage  [3040 journals]
  • Good functional results following high tibial opening-wedge osteotomy of
           knees with medial osteoarthritis
    • Authors: Arne Ekeland; Tor Kjetil Nerhus; Sigbjørn Dimmen; Elisabeth Thornes; Stig Heir
      Abstract: Publication date: Available online 9 January 2017
      Source:The Knee
      Author(s): Arne Ekeland, Tor Kjetil Nerhus, Sigbjørn Dimmen, Elisabeth Thornes, Stig Heir
      Background To report time dependent functional improvement and predictive risk factors for failure when the load in varus knees with medial osteoarthritis is shifted from the medial to the lateral knee compartment. Methods Forty-nine consecutive patients (52 knees), mean age 47 (31–64) years, underwent a high tibial opening-wedge valgus osteotomy stabilized with a Puddu plate and bone grafting. The patients were evaluated with the Knee Injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at three and six months, one, two, five and 10years postoperatively with a mean follow-up time of 8.3years (2.0–10.6). Results Mean angular correction was 8.0° (four to 12). The five subscores of KOOS increased significantly during the first year by 40–131% from preoperative values, the good results remaining throughout the 10-year follow-up for those with a surviving osteotomy. The outcome was related to the grade of preoperative osteoarthritis. Seven knees were converted to total knee arthroplasty (TKA) mean 6.2years (two to nine) post-operatively, and had a lower KOOS preoperatively than those of surviving osteotomies. The osteotomy survival rate at five years was 94% and at 10years 83%. Patients with KOOS subscore quality of life (QoL) <44 at the two-year follow-up had a 11.7 times higher risk for later TKA than those with QoL ≥44 (P=0.017). Conclusion High tibial opening-wedge osteotomy for medial knee osteoarthritis resulted in good functional recovery after one year and favorable mid-term results. It may be a good treatment option for middle-aged patients with varus knees and medial osteoarthritis in order to prevent or postpone TKA.

      PubDate: 2017-01-16T11:07:04Z
      DOI: 10.1016/j.knee.2016.12.005
  • The incidence and impact of arthroscopy in the year prior to total knee
    • Authors: S.B. Barton; G.J. McLauchlan; S.J. Canty
      Abstract: Publication date: Available online 9 January 2017
      Source:The Knee
      Author(s): S.B. Barton, G.J. McLauchlan, S.J. Canty
      Background Prior knee surgery and arthroscopy is known to increase complications and re-operations in subsequent total knee arthroplasty (TKA). We set out to examine the time dependant effect of arthroscopy on Patient Reported Outcome Measures following subsequent TKA. Methods A retrospective review of theatre and clinical records identified 186 patients who underwent TKA within a year of arthroscopy (2009–2013). Oxford knee score (OKS) data was compared with a published cohort from the same department (1708 patients). Results One hundred and eighty six patients were identified who underwent TKA within a year of arthroscopy; 112 females, 74 males; mean age 64 (SD 10); mean BMI 31.4 (SD 4.6). There was no significant difference between groups with respect to sex, age, BMI, or pre-operative OKS. One hundred and three patients underwent TKA within six months of arthroscopy. This group had a significant reduction in OKS compared to the previously published cohort (32.8 vs 35.3, p <0.005). There was no significant difference in OKS when TKA was performed more than six months after arthroscopy (35.3). The re-operation rate was 14% in the arthroscopy group, with a revision rate of 3.8% vs 1.6% in a previously published large cohort from the same institution. Conclusions There appears to be a negative impact of arthroscopy in relation to subsequent TKA which seems to be time dependent. TKA should not routinely be performed within six months of arthroscopy. This should inform guidelines on the management knee osteoarthritis.

      PubDate: 2017-01-16T11:07:04Z
      DOI: 10.1016/j.knee.2016.12.003
  • Can a biomimetic osteochondral scaffold be a reliable alternative to
           prosthetic surgery in treating late-stage SPONK?
    • Authors: M. Berruto; P. Ferrua; F. Uboldi; S. Pasqualotto; F. Ferrara; G. Carimati; E. Usellini; M. Delcogliano
      Pages: 936 - 941
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): M. Berruto, P. Ferrua, F. Uboldi, S. Pasqualotto, F. Ferrara, G. Carimati, E. Usellini, M. Delcogliano
      Background This study aimed to assess the reliability of the Maioregen® biomimetic osteochondral scaffold (Finceramica Faenza SpA, Faenza, Italy) as a salvage and joint-preserving procedure in the treatment of late-stage osteonecrosis of the knee. Methods Eleven active patients aged under 65years and presenting with clinical and radiological signs of SPONK were treated with Maioregen®. All were clinically evaluated pre-operatively and yearly thereafter for a minimum of two years. Subjective IKDC and Lysholm Knee Scale scores were used to assess clinical outcome. A VAS scale served to quantify pre-operative pain and post-operative pain. Activity levels were evaluated pre-operatively and at follow-up using the Tegner Activity Scale. Results Subjective IKDC (40±15.0 to 65.7±14.8 (mean±SD)) and Lysholm Knee Scale (49.7±17.9 to 86.6±12.7 (mean±SD)) scores improved significantly from pre-operative evaluation (p<.01). VAS scores decreased from a pre-operative mean (±SD) of 6.3±2.5 to 1.6±2.7 at two years. The Tegner Activity Scale showed no significant differences between pre-injury and two-year follow-up. Two out of the 11 patients were symptomatic at 18months post implant and progressed to condylar collapse. These patients required total knee arthroplasty. Conclusions Use of a biomimetic scaffold can be a valid option in the surgical treatment of SPONK in relatively young active patients. Indeed, this surgical technique, originally developed for osteochondritis dissecans, has been found to give good clinical results at medium-term follow-up of late-stage osteonecrosis treatment and could postpone or even avoid the need for joint replacement procedures.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.08.002
  • Survivorship and clinical outcome of the minimally invasive Uniglide
           medial fixed bearing, all-polyethylene tibia, unicompartmental knee
           arthroplasty at a mean follow-up of 7.3years
    • Authors: C. Forster-Horváth; N. Artz; M.A. Hassaballa; J.R. Robinson; A.J. Porteous; J.R. Murray; J.H. Newman
      Pages: 981 - 986
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): C. Forster-Horváth, N. Artz, M.A. Hassaballa, J.R. Robinson, A.J. Porteous, J.R. Murray, J.H. Newman
      Background Medial UKA performed in England and Wales represents seven to 11% of all knee arthroplasty procedures, and is most commonly performed using mobile-bearing designs. Fixed bearing eliminates the risk of bearing dislocation, however some studies have shown higher revision rates for all-polyethylene tibial components compared to those that utilize metal-backed implants. The aim of the study is to analyse survivorship and maximum eight-year clinical outcome of medial fixed bearing, Uniglide unicompartmental knee arthroplasty performed using an all-polyethylene tibial component with a minimal invasive approach. Methods Between 2002 and 2009, 270 medial fixed UKAs were performed in our unit. Patients were reviewed pre-operatively, five and eight years post-operatively. Clinical and radiographic reviews were carried out. Patients' outcome scores (Oxford, WOMAC and American Knee Score) were documented in our database and analysed. Results Survival and clinical outcome data of 236 knees with a mean of 7.3years follow-up are reported. Every patient with less than 4.93years of follow-up underwent a revision. The patients' average age at the time of surgery was 69.5years. The American Knee Society Pain and Function scores, the Oxford Knee Score and the WOMAC score all improved significantly. The five-year survival rate was 94.1% with implant revision surgery as an end point. The estimated 10years of survival rate is 91.3%. Fourteen patients were revised before the five-year follow-up. Conclusion Fixed bearing Uniglide UKA with an all-polyethylene tibial component is a valuable tool in the management of a medial compartment osteoarthritis, affording good short-term survivorship. Level of evidence IV

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.07.003
  • Comparison of a novel porous titanium construct (Regenerex®) to a well
           proven porous coated tibial surface in cementless total knee arthroplasty
           — A prospective randomized RSA study with two-year follow-up
    • Authors: Nikolaj S. Winther; Claus L. Jensen; Claus M. Jensen; Thomas Lind; Henrik M. Schrøder; Gunnar Flivik; Michael M. Petersen
      Pages: 1002 - 1011
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Nikolaj S. Winther, Claus L. Jensen, Claus M. Jensen, Thomas Lind, Henrik M. Schrøder, Gunnar Flivik, Michael M. Petersen
      Background Regenerex is a novel porous titanium construct with a three-dimensional porous structure and biomechanical characteristics close to that of normal trabecular bone. The aim of this study was to compare this novel construct to a well-proven porous plasma sprayed tibial (PPS) implant after total knee arthroplasty. Methods Sixty-one patients scheduled for an uncemented TKA were randomized to receive either a novel highly porous titanium construct Regenerex or the PPS tibial component. Radiostereometric analysis of the tibial components was performed postoperatively and at three, six, 12, and 24months with measurements of migration (segment motion and maximum total point motion (MTPM)). Results Knee and function scores improved significantly from preoperatively to two-year follow-up. For both the Regenerex and the PPS the majority of migration appeared during the first three months and then stabilized. No statistically significant differences in MTPM were found in any follow-up between three and 24months. The Regenerex group had a lower migration rate between 12 and 24months compared with the PPS implants (p=0.03) but the PPS group had an initial significantly lower subsidence (p=0.04). Conclusion In conclusion the Regenerex implant could prove an effective scaffold material for coating of uncemented implants but did no better than the PPS component at 24months of follow-up. identifier: NCT01936415.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.09.010
  • Patient selection does not improve the success rate of infected TKA one
           stage exchange
    • Authors: Jean-Yves Jenny; Bruno Barbe; Alain Cazenave; Olivier Roche; Philippe Massin
      Pages: 1012 - 1015
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Jean-Yves Jenny, Bruno Barbe, Alain Cazenave, Olivier Roche, Philippe Massin
      Background One stage exchange of a chronically infected total knee arthroplasty (TKA) is recommended in selected cases only. However, there is little evidence regarding the usefulness of selection criteria. The goal of this retrospective study was to compare the results of two concomitant cohorts of patients with chronically infected TKA: one treated with a routine one-stage exchange (study group) and one treated with one-stage exchange in selected cases only (control group). The hypoyhesis tested was that the failure rate and repeat surgery rate were higher in the study group than in the control group. Methods One hundred and thirty one cases were selected: 54 in the study group and 77 in the control group. There were 63 men and 68 women with a mean age of 70years. All patients were followed up for a minimal period of time of two years or until death or recurrence of infection. Results Twenty five cases had a recurrence of infection: 9/54 in the study group and 16/77 in the control group (NS). The survival rate for being free of infection after four years was 85% in the study group and 78% in the control group (NS). The repeat surgery rate was significantly higher in the control group. Conclusion The tested hypothesis was rejected. When one stage exchange is considered, patient selection does not improve outcome.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.09.002
  • Technical aspects of revision and functional outcome after revision of the
           Oxford unicompartmental knee arthroplasty
    • Authors: Matthijs P. Somford; Reinoud W. Brouwer; Pieter-Stijn W.A. Haen; Jos J.A.M. van Raay; Tom M. van Raaij
      Pages: 1020 - 1023
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Matthijs P. Somford, Reinoud W. Brouwer, Pieter-Stijn W.A. Haen, Jos J.A.M. van Raay, Tom M. van Raaij
      Background This study analysed the technical aspects of revision of the Oxford unicompartmental knee arthroplasty (OUKA) and functional results after revision. Methods In a historic cohort study we analysed all revised OUKAs that were primarily implanted at our clinic over a 10-year period (1998–2009). The primary aim was to investigate surgical difficulties encountered during revision surgery of the OUKA. Outcomes were the knee society score (KSS), WOMAC (Western Ontario and McMaster Universities), SF-36, VAS pain and VAS satisfaction after revision. Results During the study period, 331 OUKAs were inserted. With an average follow-up of six years and five months (range one month to nine years and eight months), there were 44 (13.3%) OUKAs that needed one or more revision surgery procedures. The average time to revision was three years and eight months (range one month to nine years and five months). The main reasons for revision surgery were bearing dislocation, malpositioning or loosening of a component and progression of osteoarthritis. Most revisions, mainly conversion to primary total knee arthroplasty (TKA), gave few surgical problems. Minor bone loss that needed no augmentation was seen most frequently. The functional outcomes after revision surgery were moderate. Conclusion A limited amount of surgical difficulty during revision of OUKA was found; in all total revision cases a primary TKA was implanted. However, in most patients there were moderate functional results as well as disappointing pain and satisfaction scores after revision.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.02.010
  • Knee joint position sense ability in elite athletes who have returned to
           international level play following ACL reconstruction: A cross-sectional
    • Authors: Nicola Relph; Lee Herrington
      Pages: 1029 - 1034
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Nicola Relph, Lee Herrington
      Background Following an ACL injury, reconstruction (ACL-R) and rehabilitation, athletes may return to play with a proprioceptive deficit. However, literature is lacking to support this hypothesis in elite athletic groups who have returned to international levels of performance. It is possible the potentially heightened proprioceptive ability evidenced in athletes may negate a deficit following injury. The purpose of this study was to consider the effects of ACL injury, reconstruction and rehabilitation on knee joint position sense (JPS) on a group of elite athletes who had returned to international performance. Methods Using a cross-sectional design ten elite athletes with ACL-R and ten controls were evaluated. JPS was tested into knee extension and flexion using absolute error scores. Average data with 95% confidence intervals between the reconstructed, contralateral and uninjured control knees were analyzed using t-tests and effect sizes. Results The reconstructed knee of the injured group demonstrated significantly greater angle of error scores when compared to the contralateral and uninjured control into knee flexion (p =0.0001, r =0.98) and knee extension (p =0.0001, r =0.91). There were no significant differences between the contralateral uninjured knee of the injured group and the uninjured control group. Conclusions Elite athletes who have had an ACL injury, reconstruction, rehabilitation and returned to international play demonstrate lower JPS ability compared to control groups. It is unclear if this deficiency affects long-term performance or secondary injury and re-injury problems. In the future physical therapists should monitor athletes longitudinally when they return to play.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.09.005
  • TNF-α concentrations in pre-operative synovial fluid for predicting early
    • Authors: Pawel Zietek; Violetta Dziedziejko; Krzysztof Safranow; Joanna Zietek; Marta Stępień-Słodkowska; Monika Bialecka; Maciej Zietek; Daniel Kotrych; Adam Kamiński; Aleksandra Kowalska
      Pages: 1044 - 1048
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Pawel Zietek, Violetta Dziedziejko, Krzysztof Safranow, Joanna Zietek, Marta Stępień-Słodkowska, Monika Bialecka, Maciej Zietek, Daniel Kotrych, Adam Kamiński, Aleksandra Kowalska
      Background Tumor necrosis factor-alpha (TNF-α) helps regulate neuroinflammation and anxiety and could conceivable predict early post-operative pain and function after fast-track total knee arthroplasty (TKA). Methods In patients with severe osteoarthritic knees undergoing TKA, we assessed: the correlations between pre-operative concentrations of TNF-α in synovial fluid; pre- and six-week post-operative knee function and pain; pre- and post-operative anxiety; pre- and post-operative synovial fluid concentrations of cartilage oligomeric matrix protein (COMP); age and body mass index (BMI). Results Of 100 enrolled patients, 78 had evaluable TNF-α data, and 58 had evaluable COMP data. Pre-operative TNF-α concentrations were inversely correlated with post-operative pain scores during walking (rS =−0.26, P =0.03) and with change of pain at rest during six weeks after TKA (rs =−0.28, P =0.03) and were directly correlated with a higher post-operative Knee Society score (KSS) (rS =0.43, P <0.001) and with greater increases in this score during six weeks after TKA (rS =0.33, P =0.001). Mean TNF-α concentrations were higher in the 39 patients reporting any pre-operative pain at rest than in 36 patients reporting no pre-operative pain (P =0.015) and were the only independent predictor of pre-operative pain at rest (OR=13, P =0.02). Independent predictors of better post-operative knee function were higher log-transformed TNF-α concentrations (β=0.38, P =0.002) and male sex (β=0.28, P =0.02). Conclusions High levels of pre-operative TNF-α concentrations could be used as an independent predictor of better knee function at six weeks of follow-up. In patients with lower pre-operative TNF-α concentrations, post-operative pain management may improve the early outcome of the operated joint.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.02.013
  • Testosterone may increase rat anterior cruciate ligament strength
    • Authors: W.A. Romani; S.M. Belkoff; J.H. Elisseeff
      Pages: 1069 - 1073
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): W.A. Romani, S.M. Belkoff, J.H. Elisseeff
      Background Women are more likely than men to injure the anterior cruciate ligament (ACL). Human and animal trials have linked circulating estradiol to injury rate and ligament strength. Fewer studies have examined the role of testosterone. The purpose of this study was to determine if male rats with normal testosterone levels would have stronger ACLs than castrated rats. Methods Eight castrated (group C) and eight normal (group N) 12-week-old, male Sprague–Dawley rats were used for the study. Mean testosterone levels were 0.14ng/mL (95% CI: 0.10 to 0.17) in group C and 3.54ng/mL (95% CI: 1.32 to 5.76) in group N. After euthanasia, ACL cross-sectional area was calculated, and a servohydraulic material testing unit was used to measure ligament properties. Results Specimens from both groups had similar cross-sectional area, but N specimens showed greater mean load-to-failure (34.5N [95% CI: 31.6 to 37.4] vs 29.2N [95% CI: 27.9 to 30.6]) and ultimate stress (38.7MPa [95% CI: 34.1 to 43.3] vs 31.8MPa [95% CI: 29.8 to 33.8]). Mean energy was 27.7mJ (95% CI: 23.1 to 32.2) in the N group and 23.4mJ (95% CI: 18.2 to 28.6) in the C group. Conclusions Rats with normal circulating testosterone had higher ACL load-to-failure and ultimate stress, indicating that testosterone may influence ACL strength and the injury rate of the ligament.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.07.004
  • Editorial
    • Authors: Caroline Hing; Oday Al-Dadah
      First page: 1
      Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6
      Author(s): Oday Al-Dadah, Caroline Hing

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.01.016
  • Semimembranosus tenosynovitis: Diagnosis and management of a commonly
           missed cause of posteromedial knee pain
    • Authors: Joel K Melton; Arman Memarzadeh; William H Dunbar; Mervyn J Cross
      Abstract: Publication date: Available online 28 December 2016
      Source:The Knee
      Author(s): Joel K Melton, Arman Memarzadeh, William H Dunbar, Mervyn J Cross
      Background In orthopedic and sports medicine literature there is minimal information regarding accurate diagnosis and the treatment options for tenosynovitis of the distal semimembranosus tendon. After reviewing the literature, the authors question both the etiology and treatment of this condition. Previous descriptions have associated the condition primarily with the endurance athlete but we have noted multiple cases in which this is a condition common to the ‘sprinter’ as well. There has been very little mention of this condition in recent literature but the most recent complete description of operative treatment for this condition recommends both tendon transfer and concomitant arthroscopy. We propose this condition is akin to De Quervain's tenosynovitis of the knee, with sensitive and specific signs on physical examination. Methods We describe a case series of six cases (five patients), that underwent open surgical release for semimembranosus tenosynovitis. The anatomy and the treatment options for the condition are also discussed. Results At a follow-up period of 18–64months, all cases showed improvement in the Tegner activity score following surgical release. Conclusion Diagnostic confusion can be decreased with more modern diagnostic imaging modalities than those described in the literature. The authors outline an alternative operative approach significantly decreasing surgical complexity and therefore post-operative morbidity. What is known about this subject: This is a rare condition and the surgical treatment is seldom performed. What this study adds to existing knowledge: We describe the technique for surgical decompression and reveal positive results at medium term follow-up.

      PubDate: 2016-12-30T12:38:08Z
      DOI: 10.1016/j.knee.2016.10.012
  • Validity and reliability of a novel instrumented one-legged hop test in
           patients with knee injuries
    • Authors: Karin Mani; William F. Brechue; Bernd Friesenbichler; Nicola A. Maffiuletti
      Abstract: Publication date: Available online 18 December 2016
      Source:The Knee
      Author(s): Karin Mani, William F. Brechue, Bernd Friesenbichler, Nicola A. Maffiuletti
      Background Conventional one-legged hop tests simply evaluate the total hop distance, thus neglecting important temporal and spatial parameters related to the strategy of execution, such as foot contact time. Aim To examine the validity and reliability of an instrumented one-legged hop test, the “four hops, three contacts” (4H3C) test, in patients with knee injuries. Methods The 4H3C test consists of four consecutive one-legged hops, of which individual hop distance and foot contact time are recorded by a validated floor-based photocell system. We examined the test–retest reliability, discriminant validity (involved vs. uninvolved side) and convergent validity (relation with maximal voluntary strength) of consecutive hop distance and foot contact time parameters in 50 patients with unilateral knee injuries. Results Test–retest reliability was very high for hop distance (intraclass correlation coefficients: 0.91 to 0.97) and high for contact time variables (intraclass correlation coefficients: 0.75 to 0.88). The difference between the involved and the uninvolved side was significant for all hop distance and contact time parameters (p <0.05). Maximal voluntary strength was correlated to both hop distance (r =0.67; p <0.001) and contact time (r =−0.42; p <0.01) variables. Conclusion The 4H3C is a valid and reliable test for the evaluation of single hops in patients with knee injuries and may be useful in sport and clinical settings. The interpretation of foot contact time data requires however some caution.

      PubDate: 2016-12-23T11:40:04Z
      DOI: 10.1016/j.knee.2016.09.004
  • The use of the Core Outcome Measures Index (COMI) in patients undergoing
           total knee replacement
    • Authors: Franco M. Impellizzeri; Michael Leunig; Stefan Preiss; Thomas Guggi; Anne F. Mannion
      Abstract: Publication date: Available online 13 December 2016
      Source:The Knee
      Author(s): Franco M. Impellizzeri, Michael Leunig, Stefan Preiss, Thomas Guggi, Anne F. Mannion
      Background The Core Outcome Measure Index (COMI) is a very short outcome instrument used in spine patients. The aim of this study was to examine the utility of a knee version of the COMI in patients undergoing total knee arthroplasty (TKA) by assessing the reproducibility, construct and discriminant validity, and responsiveness. Methods Preoperatively, 224 patients completed the Oxford Knee Score (OKS), EuroQoL (EQ-5D) and the COMI-Knee; 189 (84) % also completed the questionnaires at follow-up and 73 patients completed preoperatively the COMI-knee twice. Results The weighted kappa values for the COMI-knee single items ranged from 0.80 to 0.89 and the ICC for the COMI-knee (composite score), 0.86. The absolute SEM for COMI-knee was 0.4 points, i.e. four percent of the maximum value (10 points) and six percent of the average value (6.6 points). The Area Under the Curve derived from the Receiver Operating Characteristic method for the COMI-knee was 0.97 (95% CI, 0.93 to 0.99), with a cut-off value for indicating a “good” result of 2.3 (100% specificity, 87% sensitivity). Correlations between the COMI-knee and the OKS were −0.72 at baseline and −0.87 at six months. The correlations between the change scores for the COMI-knee and the change scores for the OKS and EQ5D index were 0.77 and 0.69, respectively. Conclusions The measurement properties of the COMI-knee satisfy international quality criteria and hence support its use in assessing patients undergoing TKA.

      PubDate: 2016-12-14T10:24:58Z
      DOI: 10.1016/j.knee.2016.11.016
  • Outcomes of cementless unicompartmental and total knee arthroplasty: A
           systematic review
    • Authors: Jelle P. van der List; Dana L. Sheng; Laura J. Kleeblad; Harshvardhan Chawla; Andrew D. Pearle
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): Jelle P. van der List, Dana L. Sheng, Laura J. Kleeblad, Harshvardhan Chawla, Andrew D. Pearle
      Background Aseptic loosening is a common failure mode in cemented unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). This led to the development of cementless designs but the historical outcomes were poor. Recent developments in cementless designs have improved outcomes, but the current status is unknown. Therefore, a systematic review was performed to assess recent outcomes of cementless knee arthroplasty. Methods A search was performed using PubMed, Embase and Cochrane systems and national registries for studies reporting outcomes since 2005. Fifty-two cohort studies and four registries reported survivorship, failure modes or functional outcomes of cementless UKA and TKA. Results Nine level I studies, six level II studies, three level III studies, 34 level IV studies and four registries were included. Three hundred eighteen failures in 10,309 cementless TKA procedures and 62 failures in 2218 cementless UKA procedures resulted in extrapolated five-year, 10-year and 15-year survivorship of cementless TKAs of 97.7%, 95.4% and 93.0%, respectively, and cementless UKA of 96.4%, 92.9% and 89.3%, respectively. Aseptic loosening was more common in cementless TKA (25%) when compared to UKA (13%). Functional outcomes of cementless TKA and UKA were excellent with 84.3% and 84.5% of the maximum possible scores, respectively. Conclusions This systematic review showed that good to excellent extrapolated survivorship and functional outcomes are seen following modern cementless UKA and TKA, with a low incidence of aseptic loosening following cementless UKA. Level of evidence Level IV.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.010
  • A novel 3D approach for determination of frontal and coronal plane tibial
           slopes from MR imaging
    • Authors: Amirhesam Amerinatanzi; Rodney Summers; Kaveh Ahmadi; Vijay K. Goel; Timothy E. Hewett; Edward Nyman
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): Amirhesam Amerinatanzi, Rodney Summers, Kaveh Ahmadi, Vijay K. Goel, Timothy E. Hewett, Edward Nyman
      Background The proximal tibia is geometrically complex, asymmetrical, and variable, is heavily implicated in arthrokinematics of the knee joint, and thus a contributor to knee pathologies such as non-contact anterior cruciate ligament injury. Medial, lateral, and coronal tibial slopes are anatomic parameters that may increase predisposition to knee injuries, but the extent to which each contributes has yet to be fully realized. Previously, two-dimensional methods have quantified tibial slopes, but more reliable 3D methods may prove advantageous. Aims (1) to explore the reliability of two-dimensional methods, (2) to introduce a novel three-dimensional measurement approach, and (3) to compare data derived from traditional and novel methods. Methods Medial, lateral, and coronal tibial slope geometry from both knees (left and right) of one subject were obtained via magnetic resonance images and measured by four trained observers from two-dimensional views. The process was repeated via three-dimensional approaches and data evaluated for intra- and inter-rater reliability. Results The conventional method presented a weaker Intraclass Correlation Coefficient (ICC) for the measured slopes (ranging from 0.43 to 0.81) while the resultant ICC for the proposed method indicated greater reliability (ranging from 0.84 to 0.97). Statistical analysis supported the novel approach for production of more reliable and repeatable results for tibial slopes. Conclusions The novel three-dimensional method for calculating tibial plateau slope may be more reliable than previously established methods and may be applicable in assessment of susceptibility to osteoarthritis, as part of anterior cruciate ligament injury risk assessment, and in total knee implant design.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.007
  • Contents List
    • Abstract: Publication date: December 2016
      Source:The Knee, Volume 23, Issue 6

      PubDate: 2016-12-08T08:13:13Z
  • Proximal tibial anterior open-wedge oblique osteotomy: A novel technique
           to correct genu recurvatum
    • Authors: Tae Woo Kim; Sahnghoon Lee; Jung-Ro Yoon; Hyuk-Soo Han; Myung Chul Lee
      Abstract: Publication date: Available online 2 December 2016
      Source:The Knee
      Author(s): Tae Woo Kim, Sahnghoon Lee, Jung-Ro Yoon, Hyuk-Soo Han, Myung Chul Lee
      Background For successful acute correction of genu recurvatum, accurate correction of plateau angle, restoration of anatomical axis, rigid fixation, and preservation of patellar height are essential. However, a surgical treatment that satisfies all these conditions has not yet been established. The purpose of this study was to evaluate the novel technique of proximal tibial anterior open-wedge oblique osteotomy (PT-AOWOO) for the treatment of genu recurvatum. Methods Five patients with genu recurvatum underwent PT-AOWOO from 2008 to 2013. The open-wedge center of rotation of angulation (CORA) was determined by the intersection of transverse bisector line and tibial posterior cortex to prevent secondary translational deformity. An osteotomy was performed from the distal margin of the tibial tuberosity to the planned CORA to maintain patellar height and provide sufficient space for fixation. The opening gap was calculated by the picture-archiving and communications system (PACS)–Photoshop method. Results The mean angle of recurvatum was 17° (range, 14 to 25°) preoperatively and −0.4° (range, −5° to 5°) postoperatively. The mean angle of the tibial plateau was 79.8° (range, 67 to 85°) preoperatively and 98.4° (range, 95 to 105°) postoperatively. Tibial anatomical axis was restored and the patellar height was maintained in all patients. The overall results were excellent in three patients and good in two patients. Conclusions The PT-AOWOO and its unique osteotomy level corrected the tibial plateau angle accurately, restored the sagittal tibial axis without translation, maintained patellar height, and enabled rigid fixation. This technique showed satisfactory radiologic and clinical outcomes without any complications.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.008
  • Factors predicting quadriceps femoris muscle atrophy during the first
           12weeks following anterior cruciate ligament reconstruction
    • Authors: T. Grapar Žargi; Matej Drobnič; Renata Vauhnik; Jadran Koder; Alan Kacin
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): T. Grapar Žargi, Matej Drobnič, Renata Vauhnik, Jadran Koder, Alan Kacin
      Background Factors predicting quadriceps femoris muscle (QF) atrophy during the early period after arthroscopic ACL reconstruction have not been extensively studied. It is also yet to be confirmed whether muscle atrophy is a key determinant of postoperative QF weakness. Methods Mean changes in QF volume, MVIC torque and isometric endurance time were analysed in 25 patients prior to and at four and 12 weeks after surgery. A multivariable regression model of change in QF volume was made from combination of several parameters of preoperative QF size and strength and postoperative joint recovery. The impact of QF atrophy on muscle weakness was evaluated with univariate regression and MVIC torque to volume ratio at postoperative week only. Results The model of QF volume change was significant (P<0.01) only at postoperative week 4, explaining 57% of its variation, where isometric endurance time had a negative and knee extension ROM deficit a positive weight. Change in QF volume explained (P<0.05) 46% of the MVIC torque variation at postoperative week 12. A significant change (P<0.05) in QF MVIC torque to volume ratio was observed at postoperative week 12. Conclusions Good prediction of QF atrophy in the first postoperative month can be made from studied variables, with isometric endurance and knee extension ROM deficit being the most significant contributors. The atrophy explained a large part of QF muscle weakness, whereas factors contributing to the remaining portion need further research.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.11.003
  • Supracondylar femoral osteotomy and knee joint replacement during the same
           surgical procedure in a type A haemophiliac patient with knee flexion
           deformity and ankylosis
    • Authors: Jose Luis Osma Rueda; Alejandra Oliveros Vargas; Cristian David Sosa
      Abstract: Publication date: Available online 2 December 2016
      Source:The Knee
      Author(s): Jose Luis Osma Rueda, Alejandra Oliveros Vargas, Cristian David Sosa
      Background Haemophilia A is the cause of diverse musculoskeletal disorders such as ankylosis, arthritis and associated angular deformity. There are few reported cases in patients with haemophilia A in which simultaneous supracondylar femoral osteotomy and knee joint replacement has been performed to treat knee angular deformity and ankylosis. Here we present the case of an 18year old male patient, with an evolution of two years, who was unable to walk due to the presence of an untreated supracondylar fracture in the left femur and ipsilateral haemophilic arthropathy which led him to develop an ankylosis in flexion close to 70°. Methods and results Supracondylar osteotomy of the femur and of the left knee joint was performed in the same surgical procedure. Bleeding control was achieved with a protocol of factor VIII supply. The patient was followed up for eight years, and recovered a 0 to 90° range of motion and regained his gait pattern. Conclusions This case potentially provides a new alternative approach for haemophilia patients presenting with angular deformities and complex ankylosis. We suggest that mixed lesions of intra- and extra-articular deformity in haemophiliac patients can be corrected during the same surgical intervention. In addition, interdisciplinary management including haematology for operative and immediately postoperative control of intra-bleeding using factor VIII supply and control, combined with a controlled rehabilitation plan, can yield good functional outcomes in patients with haemophilic arthropathy.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.11.007
  • A study of pre-operative presence of micro-organisms in affected knee
           joints of rheumatoid arthritis patients who need total knee arthroplasty
    • Authors: Jiang-ming Luo; Lin Guo; Hao Chen; Peng-fei Yang; Ran Xiong; Yang Peng; Liu Yang
      Abstract: Publication date: Available online 3 December 2016
      Source:The Knee
      Author(s): Jiang-ming Luo, Lin Guo, Hao Chen, Peng-fei Yang, Ran Xiong, Yang Peng, Liu Yang
      Background To evaluate, by way of intraoperative tissue culture and pathological study, the pre-operative presence of micro-organisms in knee joints of patients with rheumatoid arthritis (RA) who need total knee arthroplasty (TKA). Methods From November 2012 to January 2014, 47 patients with RA (53 knees) who needed TKA were included in this study. Patients received routine pre-operative examination and joint fluid routine and culture. Each RA patient was match-paired with one osteoarthritis (OA) patient. During arthrotomy, synovial tissue was reserved and portioned for culture, frozen section, and routine pathologic examination. Results Pre-operative infection in all knees was ruled out. There were 12 RA patients (13 knees) with positive culture results: two Escherichia coli, two Staphylococcus epidermidis, two Staphylococcus aureus, one Proteus mirabilis, one Staphylococcus warneri, one Enterococcus faecalis, one Acinetobacter baumannii, one Candida albicans, one Ochrobactrum anthropi, and one Candida glabrata. Except for microabscess found in one RA patient, all pathological sections showed mild chronic inflammation but no infection. All patients with positive culture results were administered sensitive antibiotics for six weeks after surgery. Two patients had deep infection: one had a fused knee after a failed debridement, and the second was previously treated with an amphotericin injection. Conclusion Pre-operative presence of micro-organism in knee joints of RA patients is common (24.5%). This finding of a high incidence of pre-operative presence of micro-organism in joints of RA patients before arthroplasty may suggest a role of micro-organism in the pathogenesis of prosthetic joint infection (PJI). Intraoperative synovial tissue culture is valuable for diagnosis of this condition and in instruction of antibacterial treatment.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.11.001
  • Limitations in predicting outcome following primary ACL reconstruction
           with single-bundle hamstring autograft — A systematic review
    • Authors: Vincent VG An; Corey Scholes; Vikram A Mhaskar; William Hadden; David Parker
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): Vincent VG An, Corey Scholes, Vikram A Mhaskar, William Hadden, David Parker
      Background Anterior cruciate ligament reconstruction (ACLR) is one of the most well studied and performed procedures in the world. Thus, it would be useful to develop a tool to predict patient outcomes post-operatively to allow clinicians to optimise management. Purpose To identify and summarise factors predictive of graft failure and patient-reported outcome (PROM) measures at minimum two years after ACLR with single-bundle quadruple hamstring autograft via the anteromedial portal technique. Methods Studies reporting IKDC, KOOS, Lysholm and graft failure in ACLR were systematically reviewed. A methodological score was applied to these studies, with those above the mean analysed further. Only those reporting primary predictors of patient outcomes following ACLR were included. Results Twenty-six studies satisfied our inclusion criteria. Fourteen scored above the mean 20 Downs and Black score (18.4) and were considered higher level evidence. The higher quality papers reported that younger age, female sex, higher BMI, smoking history and activity levels predicted poorer outcomes. High-grade tears of the menisci or full-thickness cartilage defects were identified as predictors of poorer PROMs. None of the factors investigated by more than a single paper were unanimously significant in predicting the outcome of ACLR. Conclusions The evidence surrounding predictors of outcome was inconsistent in design, methodology and reporting of results, hindering our ability to draw conclusions regarding the validity of the reported relationships. However, this systematic review identified several patient demographics, concomitant injuries, and surgical factors that could be investigated further in future prospective studies to create a definitive predictive model.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.006
  • Verifying the equivalence of representations of the knee joint moment
           vector from a drop vertical jump task
    • Authors: Julia K. Nichols; Oliver M. O’Reilly
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): Julia K. Nichols, Oliver M. O’Reilly
      Biomechanics software programs, such as Visual3D, Nexus, Cortex, and OpenSim, have the capability of generating several distinct component representations for joint moments and forces from motion capture data. These representations include those for orthonormal proximal and distal coordinate systems and a non-orthogonal joint coordinate system. In this article, a method is presented to address the challenging problem of evaluating and verifying the equivalence of these representations. The method accommodates the difficulty that there are two possible sets of non-orthogonal basis vectors that can be used to express a vector in the joint coordinate system and is illuminated using motion capture data from a drop vertical jump task.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.019
  • Staged total knee arthroplasty for bilateral complex knee deformities from
           Kashin–Beck disease and skeletal dysplasia
    • Authors: Ming Ling; Xueyuan Wu; Yanhai Chang; Xianghui Dong; Zhengming Sun; Li Ling; Shixun Wu; Bo Yang
      Abstract: Publication date: Available online 4 December 2016
      Source:The Knee
      Author(s): Ming Ling, Xueyuan Wu, Yanhai Chang, Xianghui Dong, Zhengming Sun, Li Ling, Shixun Wu, Bo Yang
      This study reported two cases of patients with Grade III Kashin–Beck disease (KBD) with skeletal dysplasia concomitant with complex knee deformity and functional limitation treated by staged total knee arthroplasty (TKA). Detailed pre-operative planning, bone resection, and soft tissue balancing in affected knees were performed in the surgeries in this report. The results demonstrated that TKA could correct lower limb alignment, alleviate knee pain, improve function, and provide good quality of life in people with KBD. Surgical efficacy is still lower compared with treatment for osteoarthritis; contributing factors include weak muscle strength, severe deformity and unequal length of the lower limb, weak extensor apparatus of the knee, and patient-specific factors.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.11.011
  • In response to the article published by Fukaya et al., entitled:
           “Relationships between the center of pressure and the movements of the
           ankle and knee joints during the stance phase in patients with severe
           medial knee osteoarthritis”
    • Authors: Alexandre Naaim; Claire Morisset; Paul Ornetti; Davy Laroche
      Abstract: Publication date: Available online 7 December 2016
      Source:The Knee
      Author(s): Alexandre Naaim, Claire Morisset, Paul Ornetti, Davy Laroche

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.09.006
  • Gap formation following primary repair of the anterior cruciate ligament:
           A biomechanical evaluation
    • Authors: Jelle P. van der List; Gregory S. DiFelice
      Abstract: Publication date: Available online 7 December 2016
      Source:The Knee
      Author(s): Jelle P. van der List, Gregory S. DiFelice
      Background Historically, inconsistent and unpredictable results of open primary anterior cruciate ligament (ACL) repair were reported. Recently, however, good results of arthroscopic primary ACL repair of proximal tears have been reported. Purpose of this study was to assess the direct postoperative gap formation and maximum failure load following simulated knee motion after primary ACL repair. Methods Six matched-paired human cadaveric knees (mean age: 52years, range: 48 to 56years) were used. After primary proximal ACL repair with either suture button fixation or suture anchor fixation, knees were cycled five, 50 and 100 times with a simulated active quadriceps force. Gap formation between the femoral wall and ligament was measured using a digital caliper and maximum failure load was tested. Results Gap formation after five, 50 and 100cycles of the knee were 0.30mm (±0.23), 0.75mm (±0.55) and 0.97mm (±0.70), respectively, with no significant differences between both fixation techniques. The overall maximum failure load was 243N (±143) with no difference between both techniques. Most common failure mode was slipping of suture from the fixation. Conclusion Following proximal ACL repair, gap formation of approximately one millimeter was measured after repetitious knee cycling with mean maximum failure load of 243N. These findings are likely to be sufficient for careful early active range of motion (ROM) when extrapolating from other available studies. Future studies with second-look arthroscopy are necessary to assess the gap formation and healing in patients treated with primary repair.

      PubDate: 2016-12-08T08:13:13Z
      DOI: 10.1016/j.knee.2016.10.009
  • Younger patients have less severe radiographic disease and lower reported
           outcome scores than older patients undergoing total knee arthroplasty
    • Authors: Jacob Haynes; Adam Sassoon Denis Nam Loren Schultz James Keeney
      Abstract: Publication date: Available online 5 December 2016
      Source:The Knee
      Author(s): Jacob Haynes, Adam Sassoon, Denis Nam, Loren Schultz, James Keeney
      Background Total knee arthroplasty (TKA) has been successful for many younger patients, but some experience residual symptoms or dissatisfaction. We performed this study to assess the relationship between radiographic disease severity and patient demographic features on patient reported TKA outcome scores. Methods We compared 100 TKAs performed for 82 patients ≤55years old with 100 gender-matched TKAs performed for 85 patients between 65 and 75years old. These study cases represented 25% and 21%, respectively, of TKAs performed between January 2006 and June 2011. Radiographic disease severity was determined from preoperative weight bearing AP and lateral radiographs. Patient reported outcome instruments (SF-12, Knee Society function, and WOMAC) were assessed for all patients within six months before surgery and postoperatively at a mean of 20months after TKA. Results Although younger patients had less mean articular cartilage loss (p<0.01), osteoarthritis severity (p<0.01), and Kellgren–Lawrence grade (p=0.05), they reported lower preoperative scores (p<0.01) exceeding the MCID for SF-12 mental health (8.3 points), WOMAC pain (12.1 points), and WOMAC physical function (6.9 points). While substantial improvement was noted, WOMAC pain scores remained lower than those reported by older TKA patients (11.5 points, p<0.05). Conclusion Younger patients with less severe radiographic arthritis experience significant improvement with TKA, but outcome scores do not match those attained by older patients with more severe radiographic disease.

      PubDate: 2016-12-08T08:13:13Z
  • Analysis of risk factors for poor prognosis in conservatively managed
           juvenile osteochondritis dissecans of the lateral femoral condyle
    • Authors: Hiroshi Nakayama; Tomoya Iseki; Syunichiro Kambara; Shinichi Yoshiya
      Abstract: Publication date: Available online 7 November 2016
      Source:The Knee
      Author(s): Hiroshi Nakayama, Tomoya Iseki, Syunichiro Kambara, Shinichi Yoshiya
      Background The purpose of this study was to examine factors affecting the prognosis of conservative treatment for stable juvenile osteochondritis dissecans (OCD) of the lateral femoral condyle based on review of our patient population. Methods A consecutive series of 43 knees in 37 patients with stable OCD of the lateral femoral condyle with open physes undergoing conservative treatment were included in the study. The mean age of the included subjects was 10.7±2.5years (range, seven to 16years) with the mean follow-up period of 33.3±15.1months (range, 12 to 67months). Conservative treatment consisting of prohibition of sports activities and use of a brace locking the knee in full extension was applied to all included patients. Potential prognostic factors examined were the presence of discoid meniscus, radiographic stage, lesion size on radiographs, time period from onset of symptoms to evaluation/consultation, number of hours of sporting activity per week, and age at starting sports activities. Prognosis of a patient was deemed to be poor when an apparent healing response was not detected in follow-up radiographic studies within six months. Results The prognosis was defined to be poor for 14 knees (32.6%). The presence of discoid meniscus was identified in 100% of the knees in the poor prognosis group and time-period from onset to consultation of six months or more was shown to be a risk factor with statistical significance. Conclusions A majority of patients with juvenile OCD in the lateral femoral condyle could be managed with conservative treatment. The presence of discoid meniscus and longer time-period from onset to consultation were significantly related with poor prognosis. Level of evidence IV (case series).

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2016.09.021
  • Clinical outcomes of ACL reconstruction with tibialis anterior allograft
           using an anteromedial portal approach
    • Authors: Jason Capo; Steven D. Shamah; Laith Jazrawi; Eric Strauss
      Abstract: Publication date: Available online 9 November 2016
      Source:The Knee
      Author(s): Jason Capo, Steven D. Shamah, Laith Jazrawi, Eric Strauss

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2016.06.002
  • Location of the natural knee axis for internal–external tibial
    • Authors: Daniel V. Boguszewski; Nirav B. Joshi; Paul R. Yang; Keith L. Markolf; Frank A. Petrigliano; David R. McAllister
      Abstract: Publication date: Available online 4 November 2016
      Source:The Knee
      Author(s): Daniel V. Boguszewski, Nirav B. Joshi, Paul R. Yang, Keith L. Markolf, Frank A. Petrigliano, David R. McAllister
      Background Rotating hinge and mobile bearing tray knee replacement designs utilize a single fixed axis for tibial rotation, yet there is little published information regarding the natural internal–external axis (IEA) for tibial rotation. Identifying the IEA should provide an opportunity for reproducing normal knee kinematics and maintaining the balance of forces in the soft tissues that help control rotation of the tibia. Methods The location and orientation of the IEA relative to the tibial plateau were calculated in 46 fresh frozen human cadaveric specimens using an instant center of rotation analysis at fixed knee flexion angles ranging from five degrees to 105°. Results IEA location ranged from 4.0 to 4.9mm medial and 1.7 to 5.5mm posterior to the center of the tibial plateau (from 5° to 105° of knee flexion). IEA orientation was reported relative to a reference axis perpendicular to the plane of the tibial plateau. In the frontal plane, the IEA was not significantly different from the reference axis from five degrees to 45° flexion, and 2.0° to 2.7° valgus to the reference axis from 60° to 105° flexion. In the sagittal plane, the IEA was not significantly different from the reference axis from 5° to 15° flexion, and 3.0° to 7.0° extended from the reference axis from 30° to 105° flexion. Conclusions The IEA moves posteriorly with increasing knee flexion on the tibial plateau. Placement of the IEA relative to the tibial plateau for a rotating hinge or mobile bearing tray implant may represent a compromise between design objectives for moderate and deeper knee flexion. Clinical relevance This study has relevance for future knee implant designs.

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2015.11.003
  • A soft-tissue preserving method for evaluating the impact of posterior
           tibial slope on kinematics during cruciate-retaining total knee
           arthroplasty: A validation study
    • Authors: Yifei Dai; Laurent D Angibaud; Jean-Yves Jenny; Cyril Hamad; Amaury Jung; Michael B Cross
      Abstract: Publication date: Available online 4 November 2016
      Source:The Knee
      Author(s): Yifei Dai, Laurent D Angibaud, Jean-Yves Jenny, Cyril Hamad, Amaury Jung, Michael B Cross
      Background The reconstructed posterior tibial slope (PTS) plays a significant role in restoring knee kinematics in cruciate-retaining total knee arthroplasty. However, conventional methods for the investigation of PTS can be limited by sample size or prone to errors due to damages to the bone and/or soft tissues. The purpose of this study was to validate a novel method for the evaluation of the effects of PTS on knee kinematics. Methods Seven computer-assisted cruciate-retaining TKAs were performed by two surgeons on healthy cadaveric knees. The implanted tibial baseplates allowed precise and easy modification of the PTS in situ. Knee kinematics were evaluated during passive full range of motion test. The evaluation was performed three times at each of the five PTSs in the order of 10°, seven degrees, four degrees, one degree, and back to ten degrees. The variability of the repeated measurements, inter-surgeon variation of the data, and test reproducibility were investigated. Results The test method was shown to be highly repeatable (low root-mean-squared errors) and has low sensitivity to surgeon variability (ANOVA). No statistical difference was found in the knee kinematics between the first and last measurements at 10° PTS (paired t-test). Conclusion The results suggested that the developed method can be used to investigate the impact of PTS on knee kinematics without disrupting the soft-tissue environment of the knee. The use of the novel tibial baseplate allowed for adjusting the PTS without re-cutting the tibia and removing the components. The method may be applied to improve the future investigation of PTS.

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2016.08.007
  • Morphometry of femoral rotation for total knee prosthesis according to
           gender in a Korean population using three-dimensional magnetic resonance
    • Authors: Kyoung-Tak Kang; Juhyun Son; Oh-Ryong Kwon; Changhyun Baek; Dong Beom Heo; Kyoung-Mi Park; Ho-Joong Kim; Yong-Gon Koh
      Abstract: Publication date: Available online 4 November 2016
      Source:The Knee
      Author(s): Kyoung-Tak Kang, Juhyun Son, Oh-Ryong Kwon, Changhyun Baek, Dong Beom Heo, Kyoung-Mi Park, Ho-Joong Kim, Yong-Gon Koh
      Background We aimed to evaluate differences in femoral arthometric data for 700 osteoarthritic knees (587 females and 113 males) with respect to gender in a Korean population. Methods We identified and measured the mediolateral (ML) and anteroposterior (AP) lengths, femoral aspect ratio (ML/AP), surgical epicondylar axis (SEA), and Whiteside's line (WL). In addition, the anterior, posterior, and distal bone resections of the implanted femurs were evaluated using SEA and WL as references using a three-dimensional analysis method. Results ML and AP lengths significantly differed according to gender. ML dimension and aspect ratio were greater in males than in females for a given AP dimension in the femur. No statistically significant differences in femoral rotation with SEA as a reference were observed between male and female knees; however, a significant difference was shown using WL as a reference and both affected the amount of bone resection irrespective of gender. Conclusion This study provides important guidelines for gender-specific femoral prosthesis design with different ML and AP aspect ratios and femoral rotation based on SEA and WL for Korean populations.

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2016.07.002
  • The contribution of leg press and knee extension strength and power to
           physical function in people with knee osteoarthritis: A cross-sectional
    • Authors: Michael A Tevald; Amanda M Murray; Brittney Luc; Kafai Lai; David Sohn; Brian Pietrosimone
      Abstract: Publication date: Available online 4 November 2016
      Source:The Knee
      Author(s): Michael A Tevald, Amanda M Murray, Brittney Luc, Kafai Lai, David Sohn, Brian Pietrosimone
      The purposes of this study were to 1) determine the additional contributions of leg press and knee extensor power, over and above that of strength, to the performance of physical function tasks in people with knee osteoarthritis, and 2) compare the ability of bilateral leg press to unilateral knee extensor strength and power to predict functional task performance. Methods A cross-sectional, exploratory study of 40 individuals with tibiofemoral knee osteoarthritis resulting in moderate impairments in physical function was conducted. Physical function (Get-up and Go, timed stair climb and descent, and five time chair rise) and muscle performance (leg press and knee extension strength and power) were assessed. Results After controlling for covariates and strength, leg press, but not knee extensor, power explained additional variance in physical function (11% and 21%). Conversely, adding strength to regression models including covariates and power did not consistently improve the prediction of physical function. Additionally, leg press power consistently explained more variance in physical function (44 to 57%) than involved (24 to 34%) or uninvolved (28 to 48%) knee extension power. Conclusions Leg press power may be a more functionally relevant measure of muscle performance than knee extension strength in this population. Future studies should investigate the effectiveness of interventions specifically designed to improve leg press power in people with knee osteoarthritis.

      PubDate: 2016-11-10T06:55:01Z
      DOI: 10.1016/j.knee.2016.08.010
  • Correlation between a 2D simple image analysis method and 3D bony motion
           during the pivot shift test
    • Authors: Fabio V. Arilla; Amir Ata Rahnemai-Azar; Carlos Yacuzzi; Daniel Guenther; Benjamin S. Engel; Freddie H. Fu; Volker Musahl; Richard E. Debski
      Abstract: Publication date: Available online 1 November 2016
      Source:The Knee
      Author(s): Fabio V. Arilla, Amir Ata Rahnemai-Azar, Carlos Yacuzzi, Daniel Guenther, Benjamin S. Engel, Freddie H. Fu, Volker Musahl, Richard E. Debski
      Background The pivot shift test is the most specific clinical test to detect anterior cruciate ligament injury. The purpose of this study was to determine the correlation between the 2D simple image analysis method and the 3D bony motion of the knee during the pivot shift test and assess the intra- and inter-examiner agreements. Methods Three orthopedic surgeons performed three trials of the standardized pivot shift test in seven knees. Two devices were used to measure motion of the lateral knee compartment simultaneously: 1) 2D simple image analysis method: translation was determined using a tablet computer with custom motion tracking software that quantified movement of three markers attached to skin over bony landmarks; 2) 3D bony motion: electromagnetic tracking system was used to measure movement of the same bony landmarks. Results The 2D simple image analysis method demonstrated a good correlation with the 3D bony motion (Pearson correlation: 0.75, 0.76 and 0.79). The 3D bony translation increased by 2.7 to 3.5 times for every unit increase measured by the 2D simple image analysis method. The mean intra-class correlation coefficients for the three examiners were 0.6 and 0.75, respectively for 3D bony motion and 2D image analyses, while the inter-examiner agreement was 0.65 and 0.73, respectively. Conclusions The 2D simple image analysis method results are related to 3D bony motion of the lateral knee compartment, even with skin artifact present. This technique is a non-invasive and repeatable tool to quantify the motion of the lateral knee compartment during the pivot shift test.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.003
  • Stemmed tibial revision component alignment: Does an anatomic conflict
    • Authors: Kevin M. Smith; Andrew Moorman; Sabir K. Ismaily; Stephen J. Incavo
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Kevin M. Smith, Andrew Moorman, Sabir K. Ismaily, Stephen J. Incavo
      Introduction Obtaining satisfactory coronal plane alignment is important for success in revision total knee arthroplasty (TKA). The study objective was to determine tibial coronal plane alignment after TKA when a tibial stem was used and assess if there was an anatomic conflict in tibial stemmed component alignment. Materials and methods A radiographic review of 88 revision TKA cases was performed. Full length leg radiographs were examined for varus/valgus alignment, defined as greater than or equal to three degrees from neutral 180 degrees, canal or non-canal filling tibial stems, and any native tibial bow. Results In tibias with a native valgus alignment of three or more degrees, a canal-filling stem allowed little flexibility to improve final positioning of the tibial stem and resulted in a valgus alignment of the tibial stem in 87.5% of cases, where a canal filling stem was utilized. A non-canal filling stem utilized in native valgus tibias allowed on average a two-degree improvement in tibial alignment and 64.7% of cases resulted in a neutral placement of the tibial stem. Conclusion Implanting the tibial component in a desired position is limited by type of stem and the native angulation of the tibia. When anatomic conflict exists between tibial mechanical axis and the intramedullary canal, canal filling stems may compromise coronal alignment.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.08.009
  • Impact of Charlson indices and comorbid conditions on complication risk in
           bilateral simultaneous total knee arthroplasty
    • Authors: S.K.S. Marya; Priyadarshi Amit; Chandeep Singh
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): S.K.S. Marya, Priyadarshi Amit, Chandeep Singh
      Background The purpose of this study was to evaluate the influence of Charlson indices and comorbid conditions on the risk of perioperative complications in bilateral simultaneous total knee arthroplasty (BSTKA). Methods In our retrospective analysis, 556 patients including 133 males and 423 females (mean age 65.8years), who had undergone bilateral simultaneous total knee arthroplasty between 2011 and 2014 were included. Risk factors (Charlson comorbidity index (CCI), age-adjusted Charlson comorbidity index (ACCI), and comorbid illnesses) and perioperative complications were noted, and subsequently, statistical tests were applied. Results There was significant association between Charlson indices and most of the complications (P <0.05) with high-risk ACCI groups (a score>5) bearing maximum odds for cumulative major complication (OR 4.165, P <0.001, 95% CI 1.874 to 9.256). In addition, hypertension, non-ischemic cardiac illness, and moderate to severe chronic kidney disease proved be to be determinants for major complications (P =0.031, P =0.041, and P =0.014, respectively). We also found significant associations between organ-specific illnesses and complications such as cardiac, pulmonary, neurological and renal complications (P <0.05). Conclusions Both CCI and ACCI are predictors of post-operative complications with ACCI being the better predictive determinant. Hence, these predictors should be used for risk stratification prior to patient selection for BSTKA. The influence of hypertension, non-ischemic cardiac illness and moderate to severe chronic kidney disease should also be considered during patient selection. Moreover, optimum organ function at the time of surgery should be a priority to avoid these complications.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.05.013
  • Clinical and arthrometric outcomes of an anatomic outside-in single-bundle
           anterior cruciate ligament reconstruction using a retrodrill
    • Authors: David Figueroa; Rafael Calvo; Francisco Figueroa; Daniel Paccot; Guillermo Izquierdo; Nelson Morales
      Abstract: Publication date: Available online 2 November 2016
      Source:The Knee
      Author(s): David Figueroa, Rafael Calvo, Francisco Figueroa, Daniel Paccot, Guillermo Izquierdo, Nelson Morales
      Background The main option to perform an anatomic anterior cruciate ligament (ACL) reconstruction is the anteromedial portal (AMP) technique. It has several reported complications (iatrogenic chondral injury, posterior-wall blowout, short sockets, increased risk of injury to common peroneal nerve). In an attempt to avoid these complications the outside-in (OI) technique was revived with the addition of a retrodrill. The aim of this study is to evaluate the clinical and arthrometric outcomes of a series of anatomical OI single bundle ACL reconstruction using a retrodrill. Methods Prospective case series. KT-1000 and Pivot Shift Test were done at 24 months follow-up. International Knee Documentation Committee (IKDC), Lysholm and Tegner activity scores preoperatively and at final follow-up. Complications were reported. Statistical analysis was done with t-test. Results 275 knees of 200 (73%) males and 75 (27%) females were enrolled in the study. Mean age 29.1 years (15–54). Mean follow-up 34.5 months (24–49). Mean preoperatively Lysholm Score 62 (25–95) versus 95 (76–100) at final follow-up (p<0.001) Mean preoperatively IKDC score 60 (26.4–90.8) versus 92 (59.8–100) at final follow-up (p<0.001) Mean Tegner activity Score pre injury 5 versus 5 at final follow-up. (p=0.59) Mean KT-1000 side-to-side difference 2mm (1–6). Pivot Shift test negative in 243 patients (90%); positive in 32 (10%) patients. 13 (5%) ACL re-ruptures. 2 (0.7%) infections. No other complications were reported. Conclusion OI single bundle anatomic ACL reconstruction using a retrodrill is a valid and safe option that avoids the complications reported with the AMP technique.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.07.007
  • Can an expansion device be used in anterior cruciate ligament
           reconstruction' An in vitro study of soft tissue graft tibial fixation
    • Authors: Oscar Martel; Gerardo L. Garcés; Alejandro Yánez; Alberto Cuadrado; Juan F. Cárdenes
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Oscar Martel, Gerardo L. Garcés, Alejandro Yánez, Alberto Cuadrado, Juan F. Cárdenes
      Background The purpose of this study was to compare the mechanical properties of an interference screw with an expansion device in anterior cruciate ligament (ACL) reconstruction. Methods A total of 52 porcine tibia and 20 polyurethane foam blocks (0.16g/cm3) were used. Forty pullout tests were carried out to combine the two types of bones – surrogate and porcine – with the two fixation systems: interference screw and expansion device (n=10 per group). Thirty-two cyclic tests (n=8 per group) were carried out with both fixation devices in porcine bone at two different force amplitudes (100N and 200N). Results Stiffness and load values (mean±SD) at six millimeters of displacement for the expansion device and the interference screw were 74±33N/mm, 318±135N, and 52±28N/mm, 205±70N, respectively, showing a difference in stiffness (P =0.016) and load at six millimeters of displacement (P =0.001). No correlation between insertion torque and the ultimate failure load was found for both fixation devices tested. In cyclic tests, significantly higher (P<0.001) numbers of cycles (mean±SD) were reached with the expansion device (81,014±30,291 at 100N; 13,462±11,351 at 200N) than with the interference screw (15,100±8623 at 100N; 343±113 at 200N) at six millimeters of displacement. Conclusion The use of an expansion device for ACL reconstructions seemed to be a promising alternative to an interference screw. Insertion torque alone was not a useful predictor of graft fixation strength in ACL reconstructions.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.009
  • Improved ACL reconstruction outcome using double-layer BPTB allograft
           compared to that using four-strand hamstring tendon allograft
    • Authors: Yingzhen Niu; Chao Niu; Xiaomeng Wang; Junhang Liu; Pengkai Cao; Fei Wang; Jinghui Niu
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Yingzhen Niu, Chao Niu, Xiaomeng Wang, Junhang Liu, Pengkai Cao, Fei Wang, Jinghui Niu
      Background This study compared the clinical outcomes of anterior cruciate ligament reconstruction using double-layer bone–patellar tendon–bone (DBPTB) allografts and four-strand hamstring (4SHS) grafts. Methods This prospective randomized controlled trial included 101 patients. Of these, 50 patients received DBPTB allografts, and 51 received 4SHS grafts. Evaluations included KT-1000 arthrometer measurements, Lachman tests, pivot-shift tests, the International Knee Documentation Committee (IKDC) classification and Lysholm scores at three year postoperative follow-up. Results Two DBPTB patients (four percent) and nine 4SHS patients (17.6%) had graft failures, which was significantly different (P =0.028). The DBPTB group had significantly better Lachman test, IKDC knee score and Lysholm score results than the 4SHS group (P <0.05). However, these differences were below the threshold for clinical significance. Conclusions DBPTB allografts had fewer graft failures at three years than 4SHS grafts for anterior cruciate ligament reconstruction; and there were statistically significant differences but not clinically significant differences between DBPTB and 4SHS grafts in terms of the KT1000 test, IKDC and Lysholm scores.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.015
  • Subjective evaluation before and after total knee arthroplasty using the
           2011 Knee Society Score
    • Authors: Yuichi Kuroda; Tomoyuki Matsumoto; Koji Takayama; Kazunari Ishida; Ryosuke Kuroda; Masahiro Kurosaka
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Yuichi Kuroda, Tomoyuki Matsumoto, Koji Takayama, Kazunari Ishida, Ryosuke Kuroda, Masahiro Kurosaka
      Background Patient satisfaction has been recognized as an important evaluation of total knee arthroplasty (TKA). Therefore, the 2011 Knee Society Knee Scoring System (2011 KSS) was developed in order to quantify patient satisfaction, expectations, and physical activities following TKA. However, very few reports have described subjective evaluation before TKA using the 2011 KSS, as the scoring system is still relatively new. Therefore, the degree of improvement and change over time after TKA has not been evaluated. Methods Forty-nine consecutive patients (79 knees) with a mean age of 74.8±7.3years were prospectively included in the study and evaluated preoperatively and one year postoperatively. The following questions were assessed using the 2011 KSS: (1) Do patient-derived clinical scores improve after TKA' (2) Do patient-derived clinical scores before TKA correlate with those after TKA' and (3) Are there correlations among each category of the 2011 KSS score' Results The majority of categories showed significant improvements after TKA. The preoperative functional activities score was positively correlated with the postoperative symptoms, functional activities, and objective score. Each category of the 2011 KSS score correlated with others postoperatively. Conclusions All patient-derived scores except for patient expectation significantly improved postoperatively. The more functionally active patients before receiving TKA acquired more successful objective and functional outcomes, and the postoperative knee condition was directly influenced by each subscale of the 2011 KSS.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.008
  • Validation of varus stress radiographs for anterior cruciate ligament and
           posterolateral corner knee injuries: A biomechanical study
    • Authors: Lucas S. McDonald; Robert A. Waltz; Joseph R. Carney; Christopher B. Dewing; Joseph R. Lynch; Dean B. Asher; Dustin J. Schuett; Lance E. LeClere
      Abstract: Publication date: Available online 30 October 2016
      Source:The Knee
      Author(s): Lucas S. McDonald, Robert A. Waltz, Joseph R. Carney, Christopher B. Dewing, Joseph R. Lynch, Dean B. Asher, Dustin J. Schuett, Lance E. LeClere
      Purpose The purpose of this study was to determine the effect of isolated anterior cruciate ligament (ACL) insufficiency on the radiographic varus stress test, and to provide reference data for the increase in lateral compartment opening under varus stress for a combined ACL and PLC injury. Methods Ten cadaveric lower extremities were fixed to a jig in 20° of knee flexion. Twelve Newton-meter (Nm) and clinician-applied varus loads were tested, first with intact knee ligaments, followed by sequential sectioning of the ACL, fibular collateral ligament (FCL), popliteus tendon and the popliteofibular ligament (PFL). Lateral compartment opening was measured after each sequential sectioning. Results Maximum increase in lateral compartment opening for an isolated ACL deficient knee was 1.06mm with mean increase of 0.52mm (p=0.021) for the clinician-applied load. Mean increase in lateral compartment opening in an ACL and FCL deficient knee compared to the intact knee was 1.48mm (p<0.005) and 1.99mm (p<0.005) for the 12-Nm and clinician-applied loads, respectively, increasing to 1.94mm (p<0.005) and 2.68mm (p<0.005) with sectioning of the ACL and all PLC structures. Conclusions Anterior cruciate ligament deficiency contributes to lateral compartment opening on varus stress radiographs though not sufficiently to confound previously established standards for lateral ligament knee injuries. We did not demonstrate the same magnitude of lateral compartment opening with sectioning of the PLC structures as previously reported, questioning the reproducibility of varus stress radiographic testing among institutions. Clinicians are cautioned against making surgical decisions based solely on current standards for radiographic stress examinations.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.07.001
  • Patients with isolated lateral osteoarthritis: Unicompartmental or total
           knee arthroplasty'
    • Authors: J.P. van der List; H. Chawla; H.A. Zuiderbaan; A.D. Pearle
      Abstract: Publication date: Available online 31 October 2016
      Source:The Knee
      Author(s): J.P. van der List, H. Chawla, H.A. Zuiderbaan, A.D. Pearle
      Background Lateral unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) are both reliable treatment options for patients with isolated lateral osteoarthritis (OA). However, studies comparing both procedures are scarce. Aims of this study were to (I) compare short-term functional outcomes following lateral UKA and TKA and (II) assess the role of patient characteristics on outcomes as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Methods In this retrospective cohort study, 82 patients (48 undergoing lateral UKA and 34 undergoing TKA) were identified that presented with lateral OA and completed the WOMAC. Independent t-tests were used to compare outcomes following lateral UKA and TKA. Results Mean follow-up was 2.8 years (range: 2.0 – 5.0 years). Preoperatively, no differences between lateral UKA and TKA were seen (50.1±13.5 and 53.3±17.1, respectively, p =0.551). Postoperatively, lateral UKA patients reported better overall outcomes than TKA (90.5±11.7 vs. 81.8±17.9, p =0.017). Subgroup analysis showed better outcomes following lateral UKA than TKA in patients younger than 75 years (92.1±9.9 vs. 81.3±19.6, p =0.014) and in females (91.6±9.9 vs. 81.0±18.2, p =0.014). Conclusion These findings indicate that lateral UKA has superior short-term functional outcomes compared to TKA in patients with isolated lateral OA. Better outcomes were especially seen in younger patients and females. These findings may help orthopedic surgeons choose treatment for patients presenting with lateral OA and optimize treatment for individual patients.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.007
  • Different optimal alignment but equivalent functional outcomes in medial
           and lateral unicompartmental knee arthroplasty
    • Authors: Jelle P. van der List; Harshvardhan Chawla; Jordan C. Villa; Andrew D. Pearle
      Abstract: Publication date: Available online 31 October 2016
      Source:The Knee
      Author(s): Jelle P. van der List, Harshvardhan Chawla, Jordan C. Villa, Andrew D. Pearle
      Introduction Several differences in kinematics, functional outcomes and alignment exist between medial and lateral unicompartmental knee arthroplasty (UKA). Therefore, the purpose of this study was (1) to compare functional outcomes between both procedures with the hypothesis that both have equivalent outcomes and (2) to assess the role of preoperative and postoperative alignment on functional outcomes in both procedures. Methods Patients who underwent UKA were included when overall function — using Western Ontario and McMaster Universities Arthritis (WOMAC) score – and joint awareness – using Forgotten Joint Score (FJS) — were available preoperatively and at minimum two-year follow-up. A total of 143 medial UKA and 36 lateral UKA patients reported outcomes at mean 2.4-years follow-up (range 2.0 to 5.0year). Results Preoperatively and postoperatively, no differences were seen between medial and lateral UKA in overall function (89.8±11.7 vs. 90.2±12.4, respectively, p =0.855) and joint awareness (71.2±24.5 vs. 70.9±28.2, respectively, p =0.956). With neutral postoperative alignment (−1° to three degrees), less joint awareness was noted following medial UKA than lateral UKA (72.6±22.6 vs. 55.3±28.5, p=0.024). With undercorrection (three degrees to seven degrees), however, following lateral UKA less joint awareness (85.3±19.5 vs. 68.2±26.8, p=0.020) and better functional outcomes (96.0±5.4 vs. 88.5±11.6, p=0.001) were noted than medial UKA. Conclusion Equivalent functional outcomes were noted between medial and lateral UKA at short-term follow-up but different optimal alignment angles seem to exist for both procedures. Level of evidence Level III therapeutic study.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.08.008
  • How accurately does high tibial osteotomy correct the mechanical axis of
           an arthritic varus knee' A systematic review
    • Authors: Maxim Van den Bempt; Wouter Van Genechten; Toon Claes; Steven Claes
      Abstract: Publication date: Available online 22 October 2016
      Source:The Knee
      Author(s): Maxim Van den Bempt, Wouter Van Genechten, Toon Claes, Steven Claes
      Background The aim of this study was to give an overview of the accuracy of coronal limb alignment correction after high tibial osteotomy (HTO) for the arthritic varus knee by performing a systematic review of the literature. Methods The databases PubMed, MEDLINE and Cochrane Library were screened for relevant articles. Only prospective clinical studies with the accuracy of alignment correction by performing HTO as primary or secondary objective were included. Results Fifteen studies were included in this systematic review and were subdivided in 23 cohorts. A total of 966 procedures were considered. Nine cohorts used computer navigation during HTO and the other 14 cohorts used a conventional method. In seven computer navigation cohorts, at least 75% of the study population fell into the accepted “range of accuracy” (AR) as proposed by the different studies, but only six out of 14 conventional cohorts reached this percentage. Four out of eight conventional cohorts that provided data on under- and overcorrection, had a tendency to undercorrection. Conclusions The accuracy of coronal alignment corrections using conventional HTO falls short. The number of procedures outside the proposed AR is surprising and exposes a critical concern for modern HTO. Computer navigation might improve the accuracy of correction, but its use is not widespread among orthopedic surgeons. Although HTO procedures have been shown to be successful in the treatment of unicompartmental knee arthritis when performed accurately, the results of this review stress the importance of ongoing efforts in order to improve correction accuracy in modern HTO.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.10.001
  • Candidate methylated genes in osteoarthritis explored by bioinformatics
    • Authors: Jie Liu; Yangquan Hao; Yugui Wang; Shouye Hu; Ke Xu; Chao Lu
      Abstract: Publication date: Available online 31 October 2016
      Source:The Knee
      Author(s): Jie Liu, Yangquan Hao, Yugui Wang, Shouye Hu, Ke Xu, Chao Lu
      Background This study aimed to explore potential novel genes correlated with osteoarthritis (OA). Methods The gene expression profile of GSE48422 was downloaded from the Gene Expression Omnibus (GEO) database. This dataset included five arthritic cartilage samples and five non-arthritic cartilage samples from five female OA patients. Differentially methylated genes (DMGs) between the two kinds of samples were identified, followed by their functional analysis and protein–protein interaction (PPI) analysis. Furthermore, the Comparative Toxicogenomics Database (CTD) was used to further identify OA-related genes among these DMGs. Results In total, 965 hypermethylated genes and 112 hypomethylated genes were identified in the arthritic cartilage samples. The hypermethylated genes (e.g., ADCY4 and ADCY6) were significantly related to the calcium signaling pathway and gonadotropin-releasing hormone signaling pathway, while the hypomethylated genes were implicated in the mammalian target of rapamycin signaling pathway. In the PPI network, several genes had a higher degree, such as ADCY4, ADCY6 and GPR17, and they interacted with each other. Additionally, 565 DMGs were predicted to be associated with OA, and five of them (e.g., COMP and EDIL3) were previously identified as OA markers. Conclusions The methylation of genes ADCY4, ADCY6 and GPR17, as well as the gonadotropin-releasing hormone signaling pathway, was newly found to be potentially associated with OA. They may be novel OA markers.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.09.020
  • A cost comparison of unicompartmental and total knee arthroplasty
    • Authors: Sheila Shankar; Matthew W. Tetreault; Briana J. Jegier; Gunnar B. Andersson; Craig J. Della Valle
      Abstract: Publication date: Available online 31 October 2016
      Source:The Knee
      Author(s): Sheila Shankar, Matthew W. Tetreault, Briana J. Jegier, Gunnar B. Andersson, Craig J. Della Valle
      Background Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty (TKA) in appropriately selected patients. There is a paucity of data comparing hospital resource utilization and costs for UKA versus TKA. Methods We retrospectively reviewed 128 patients who underwent UKA or TKA for osteoarthritis by a single surgeon in the 2011 Fiscal Year. Sixty-four patients in each group were matched based on sex, age, race, body mass index, Charlson Comorbidity Index, and insurance type. Clinical data were obtained from medical records while costs were obtained from hospital billing. Bivariate analyses were used to compare outcomes. Results Both anesthesia and operative time (minutes) were significantly shorter for patients undergoing UKA (125.7 vs. 156.4; p <0.001, and 81.4 vs. 112.2; p <0.001). UKA patients required fewer transfusions (0% vs. 11.0%; p =0.007) and had a shorter hospital stay (2.2 vs. 3.8days; p <0.001). 96% of UKAs were discharged home compared with 75% of TKAs (p <0.001). Hospital direct costs were lower for UKA ($7893 vs. $11,156; p <0.001) as were total costs (hospital direct costs plus overhead; $11,397 vs. $16,243; p <0.001). Supply costs and implant costs were similarly lower for UKA ($701 vs. $781; p <0.001, and $3448 vs. $5006; p <0.001). Conclusion Our data suggest that UKA provides a cost-effective alternative to TKA in appropriately selected patients. As the number of patients with end-stage arthritis of the knee requiring surgical care continues to rise, the costs of caring for these patients must be considered. Level of Evidence Level III, case control study.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2015.11.012
  • An unambiguous technique for locating the adductor tubercle and using it
           to identify the joint line
    • Authors: Ing-Ho Chen; Wen-Tien Wu; Chen-Chie Wang; Kuan-Lin Liu; Kuang-Ting Yeh; Cheng-Huan Peng
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Ing-Ho Chen, Wen-Tien Wu, Chen-Chie Wang, Kuan-Lin Liu, Kuang-Ting Yeh, Cheng-Huan Peng
      Background If the adductor tubercle could be accurately located, it would be a useful landmark for identifying the joint line during knee arthroplasty. This study aimed to develop an intraoperative technique to improve its locating accuracy. Methods Evaluation of bone specimens and cadaveric knees revealed that the proximal slope of the adductor tubercle (PSAT) turns from the medial surface vertically into the superior surface of the medial condyle, which forms a distinctive edge. This provided an ideal landmark that could be unambiguously engaged using a tipped instrument. Using the PSAT as a reference point, we measured the distance to the joint line (the proximal–distal condylar length; PDCL) in eight pairs of cadaveric knees, and evaluated the inter-observer variability. Next, we measured 120 knees undergoing total knee arthroplasty to test this technique in a normal population. Finally, we divided each PDCL by the respective anterior–posterior condylar length (APCL) to create a ratio that could predict the PDCL regardless of knee size. Results The intra-class correlation coefficient (ICC) was 0.86 for the cadaveric measurements. The mean PDCL from the operated knees was 46mm (coefficient of variance (CV): eight percent). The mean PDCL/APCL ratio was 0.77 (CV: six percent). The high ICC and low CV indicated that using the PSAT was a reliable technique. Conclusion The PSAT is an ideal surgical landmark. The tipped instrument engagement technique with it may help to unambiguously locate the adductor tubercle in order to identify the joint line during knee arthroplasty.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.05.014
  • Effects of suture site or penetration depth on anchor location in
           all-inside meniscal repair
    • Authors: Ryohei Uchida; Tatsuo Mae; Kunihiko Hiramatsu; Ryo Iuchi; Kazutaka Kinugasa; Konsei Shino; Hideki Yoshikawa; Ken Nakata
      Abstract: Publication date: Available online 29 October 2016
      Source:The Knee
      Author(s): Ryohei Uchida, Tatsuo Mae, Kunihiko Hiramatsu, Ryo Iuchi, Kazutaka Kinugasa, Konsei Shino, Hideki Yoshikawa, Ken Nakata
      Background To evaluate the effects of suture site or penetration depth on anchor location in all-inside meniscal repair. Methods Eight fresh-frozen cadaveric knees were evaluated after meniscal repair using eight FasT-Fix360 (FF360) devices (Smith & Nephew Endoscopy, Andover, MA) (16 anchors) for each knee. The penetration depth was 14mm, the distance same from the periphery to insertion point, in four knees (Group A) and that in the remaining four knees (Group B) was 18mm. The anchor location in two groups was evaluated after attentive dissection. Results Of 32 anchors for the medial meniscus, 94% were on the capsule, including the superficial medial collateral ligament (sMCL) in both groups. For the lateral meniscus, 47% anchors in Group A and 44% anchors in Group B were on the capsule. Total three anchors were over the lateral collateral ligament (LCL), whereas 15 anchors were behind the popliteus tendon (POP). Although all three anchors settled in the subcutaneous fat were in Group B, no significant difference was observed in anchor location between two groups. Conclusions Secure fixation to thin membranous tissue can be achieved for the medial meniscal repair using FF360, while some were located in/on bunchy LCL or POP in lateral meniscal repair. Only anchors with additional four-millimeter penetration depth were in the subcutaneous fat, although there was no effect of the penetration depth to anchor location. Clinically, for lateral meniscal repair, penetrating toward POP/LCL should be avoided and four-millimeter deeper penetration depth might be a risk for the subcutaneous irritation.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.012
  • Rotating platform versus fixed bearing total knee arthroplasty at mid-term
    • Authors: J. Ryan Martin; Taylor R. Beahrs; Keith A. Fehring; Robert T. Trousdale
      Abstract: Publication date: Available online 2 November 2016
      Source:The Knee
      Author(s): J. Ryan Martin, Taylor R. Beahrs, Keith A. Fehring, Robert T. Trousdale
      Background Rotating platform posterior stabilized (RP) total knee arthroplasty (TKA) was initially developed in part to decrease polyethylene wear and to improve patellar tracking. There have been limited studies evaluating the longevity and causes of reoperation or revision for this implant. The following study compares mid-term survival rates and causes for reoperation between fixed bearing (FB) TKAs. Methods We identified 11,416 patients who underwent a primary posterior stabilized TKA between 2001 and 2013. This group was stratified to include patients with a RP (n=926) and FB (n=10,490) TKA design. Kaplan–Meier survival rates for each complication that led to reoperation were determined at five- and 10-years. Univariate hazard ratios were determined for the most common causes for reoperation and overall implant survival rates. A multivariate analysis was performed to account for the age, gender and preoperative diagnosis discrepancy between groups. Results The reoperation data demonstrated statistically increased all-cause reoperation rate (p=<0.001) and reoperation rate for stiffness in the RP group (p=0.001). After adjusting for demographic variables we noted no statistically significant differences in reoperation rate and reoperation for stiffness. Additionally, a statistically significant decrease was noted in all-cause revision (p=0.024) and revision for aseptic loosening or osteolysis in the RP group (p=0.029). Conclusion After adjusting for patient demographic differences, we noted a statistically significant decrease in the overall revision and revision for aseptic loosening or osteolysis rates in the RP group.

      PubDate: 2016-11-03T05:38:26Z
      DOI: 10.1016/j.knee.2016.06.004
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