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Journal Cover   The Knee
  [SJR: 1.137]   [H-I: 44]   [13 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0968-0160
   Published by Elsevier Homepage  [2812 journals]
  • The effect of femoral tunnel widening on one-year clinical outcome after
           anterior cruciate ligament reconstruction using Ziploop® technology
           for fixation in the cortical bone of the femur
    • Abstract: Publication date: Available online 3 July 2015
      Source:The Knee
      Author(s): Benjamin Basson , Rémi Philippot , Thomas Neri , Jean François Meucci , Bertrand Boyer , Frédéric Farizon
      Background The effect of femoral tunnel widening on clinical results after anterior cruciate ligament (ACL) reconstruction has rarely been investigated. In our study, ACL reconstructions were performed using semitendinosus and gracilis (STG) tendon grafts and single cortical fixation on the femoral side. The aim was to analyse femoral tunnel widening at one year and evaluate the effect of femoral tunnel widening on clinical and laximetric outcome. Methods Forty-six patients were enrolled in this prospective continuous single operator monocenter study. Clinical protocol included preoperative and one-year evaluation with subjective and objective clinical scores of the International Knee Documentation Committee (IKDC). Computerized tomography (CT) scan was used for radiographic examination at one-year follow-up. The amount of femoral tunnel widening was measured by means of the 3D image processing OsiriX software. The cross-sectional area of each tunnel was measured at four different locations. Results The subjective IKDC score improved from a preoperative score of 50 to a one-year postoperative score of 81.8. The side-to-side difference in knee laxity evolved from 2.94mm to 0.74mm. The objective IKDC score at last follow-up was rated A in 27 patients and B in 17. CT scan data revealed a mean cone shape widening of the femoral tunnel of 49.32%. Femoral tunnel widening at the level of the joint (F4) was negatively correlated with the IKDC subjective score at one year. Conclusion This study revealed a significant widening of the femoral tunnel by demonstrating its conical shape at one postoperative year. A significant correlation could be established between femoral tunnel widening close to the joint and IKDC scores.


      PubDate: 2015-07-05T13:37:45Z
       
  • A suspected genetic form of bilateral osteochondritis dissecans of the
           knee in a Dutch family
    • Abstract: Publication date: Available online 27 June 2015
      Source:The Knee
      Author(s): J. Gorter , J.J.A.M. van Raay
      Osteochondritis dissecans (OCD) mostly has an idiopathic origin, but syndromic and familial forms have been reported. Mutations of the aggrecan (ACAN) and COL9A2 genes are associated with familial OCD, but these patients present with syndromic features. This article describes a mother and a daughter who both have bilateral OCD of the medial femoral condyles, and the monozygotic twin sister of the mother who has confirmed unilateral OCD (and possible bilateral OCD) of the medial femoral condyle. No short stature or any other syndromic features were present. None of the syndromic features associated with ACAN or COL9A2 mutations or any other known syndromes were present in this case. This case suggests a possible unknown genetic anomaly. Level of evidence: IV case report.


      PubDate: 2015-07-01T12:57:34Z
       
  • Hip abductor strength in people with knee osteoarthritis: A
           cross-sectional study of reliability and association with function
    • Abstract: Publication date: Available online 30 June 2015
      Source:The Knee
      Author(s): Michael A. Tevald , Amanda Murray , Brittney A. Luc , Kafai Lai , David Sohn , Brian Pietrosimone
      Background To investigate the clinical importance of hip abductor (HA) strength in people with knee osteoarthritis (OA), the purposes of this study were to 1) compare the association of HA strength and physical function to that of knee extensor (KE) strength and physical function, and 2) determine the reliability of the assessment of HA strength using a hand-held dynamometer. Methods Thirty-five individuals [58 years standard deviation 10 years old] with knee osteoarthritis participated. Physical function was assessed with performance-based [Get-Up and Go (GUG), stair climb and descent (SC), and five times chair rise (CR)] and self-reported (WOMAC function) measures. The relationship between strength and function was assessed using bivariate correlation and hierarchical multiple regression models. Reliability across sessions was assessed in 25 subjects. Results In the bivariate models, both KE and HA strength were both significantly associated with performance-based measures of function, but not WOMAC function. After controlling for anthropometric factors and KE strength in the hierarchical models, HA made significant independent contributions to the prediction of GUG and SC, but not CR or WOMAC function. The reliability of HA strength was excellent (ICC2, 3 =0.94; 95% CI=0.86–0.97), while the minimum detectable change (MDC95) was 0.29Nm/kg (95% CI=0.23–0.41). Conclusion HA strength can be reliably measured and is closely associated with functional performance in people with knee OA. Clinical Relevance These results provide preliminary evidence suggesting that HA strength may be an important rehabilitation target for the conservative management of knee OA.


      PubDate: 2015-07-01T12:57:34Z
       
  • Clinical and functional outcome after anterior cruciate ligament
           reconstruction using the LARS™ system at a minimum follow-up of
           10years
    • Abstract: Publication date: Available online 27 June 2015
      Source:The Knee
      Author(s): Thomas M. Tiefenboeck , Elisabeth Thurmaier , Michael M. Tiefenboeck , Roman C. Ostermann , Julian Joestl , Markus Winnisch , Mark Schurz , Stefan Hajdu , Marcus Hofbauer
      Background Since the 1980's several artificial ligaments were used for reconstruction of the anterior cruciate ligament (ACL) serving different complications. The aim of this study was to assess the clinical and functional outcomes of primary ACL reconstruction using the Ligament Augmentation Reconstruction System (LARS™) with a minimum follow-up of 10-years. The LARS™ presents a synthetic material consisting of non-absorbing polyethylene terephthalate fibres used for ligament reconstruction. Methods Outcomes of 18 patients who underwent arthroscopic ACL reconstruction using the LARS™ system between 2000 and 2004 with a minimum follow-up of 10years were observed. The International Knee Documentation Committee score (IKDC), Visual Analog Scale (VAS), Lysholm score, and Tegner Activity Scale were assessed. Clinical assessment was performed by Lachman testing, assessment of side-to-side difference on KT-2000 testing and plain radiography evaluation of osteoarthritis. Results There were seven males and 11 females, mean age 29years (range, 18 to 44years) and a mean follow-up of 151.5 months. Five patients (27.8%) sustained a re-rupture of the LARS™ system and underwent revision surgery after a mean time of 23months and four patients (22.2%) presented with a re-rupture. The average IKDC score was 76.60±18.18, the average Lysholm score was 88.00±10.07 and the average Tegner activity score was five at final follow-up. Conclusion Our results indicate that the LARS™ system should currently not be suggested as a potential graft for primary reconstruction of the ACL. In special cases, however, the LARS™ system can serve as an alternative graft. Level of evidence: Level IV, retrospective study.


      PubDate: 2015-07-01T12:57:34Z
       
  • Case series: Revision anterior cruciate ligament reconstructions using
           patellar tendon autografts
    • Abstract: Publication date: Available online 27 June 2015
      Source:The Knee
      Author(s): Yuji Takazawa , Hiroshi Ikeda , Yoshitomo Saita , Muneaki Ishijima , Masataka Nagayama , Haruka Kaneko , Yohei Kobayashi , Shinnosuke Hada , Ryo Sadatsuki , Kazuo Kaneko
      Background Using intra-operative findings and clinical results, including return to play (RTP) at the pre-injury level, this study investigated the causes of primary graft failure after revision anterior cruciate ligament (ACL) reconstruction with bone–patellar-tendon–bone (BPTB) autografts. Methods A total of 54 patients were followed for a mean of 38.2±10.2months post-surgery. Subjective and objective results were evaluated using single assessment numeric evaluation (SANE) scores, Lachman tests, KT-2000 arthrometer results, and pivot-shift tests. The change in each patient's Tegner activity scale and RTP at the pre-injury level were also evaluated. Results Inappropriate positioning of the tunnels was the most important reason (54%) for primary graft failure. After revision surgery, anterior knee stability was significantly improved (1.2 (mean)±1.2 (SD)mm vs 4.5(mean) ±1.9 (SD)mm; P<0.01). Two (4%) patients sustained revision graft ruptures while two (4%) sustained contralateral knee ACL tears. The rate of RTP at the pre-injury level was 67% (36 patients), and mean SANE scores at the time of RTP were higher than before surgery (74.8±13.8 points vs 24.1±16.4; P<0.001). The average time from primary graft failure to revision surgery was shorter (12.2 (mean)±4.0 (SD) vs 37.6 (mean)±8.8 (SD)months; P<0.01) and the ratio of major cartilage injury was lower (39% vs 83%; P<0.05) in the RTP group than that in the non-RTP group. Conclusions The time from primary graft failure to revision surgery and the extent of the cartilage injury are major factors in RTP after revision ACL reconstructions.


      PubDate: 2015-07-01T12:57:34Z
       
  • Obesity and the absence of trochlear dysplasia increase the risk of
           revision in patellofemoral arthroplasty
    • Abstract: Publication date: Available online 19 June 2015
      Source:The Knee
      Author(s): Ming Han Lincoln Liow , Graham Seow-Hng Goh , Darren Keng-Jin Tay , Shi-Lu Chia , Ngai-Nung Lo , Seng-Jin Yeo
      Purpose Proper indications and patient selection are paramount in Patellofemoral Arthroplasty (PFA). Although factors predicting outcomes in Total Knee Arthroplasty (TKA) have been studied, there are no such studies for modern PFA. This retrospective study reports the mid-term clinical and radiological outcomes and survivorship of PFA, investigating the risk factors associated with poorer outcomes and higher revision rates. Methods Fifty-one patients (51 knees) with isolated patellofemoral arthritis underwent PFA using a second-generation implant. Mean follow-up was 4.1years (range, 2.2–6.1). We stratified the cohort into Obese (body mass index (BMI)≥30kg/m2, n=16), Overweight (BMI 25–29.9kg/m2, n=20) and Control (BMI 18.5–24.9kg/m2, n=15) groups. The same cohort was stratified based on the presence (n=11) or absence (n=40) of trochlear dysplasia (TD). Results Mean Knee Society objective and function scores, Melbourne Knee score and Physical Component Score of Short-Form 36 improved significantly. Obesity was associated with no significant improvement in Melbourne Knee score and Knee Society function score (p>0.05), a higher incidence of radiographic outliers and lower patient satisfaction. There was no significant difference in outcomes between the TD and Non-TD groups at two years (p>0.05). Survivorship was 92.2%. Three revisions for progression of tibiofemoral osteoarthritis were noted in the Non-TD and obese or overweight groups. Conclusions Patients with obesity and the absence of trochlear dysplasia are at a potentially higher risk of revision surgery to TKA and should be counseled that PFA may represent a “bridging” procedure. Level of Evidence III


      PubDate: 2015-06-26T12:42:54Z
       
  • Comprehensive assessment of patellar morphology using computed
           tomography-based three-dimensional computer models
    • Abstract: Publication date: Available online 19 June 2015
      Source:The Knee
      Author(s): Ai-Bing Huang , Xiao Luo , Chang-Hui Song , Ji-Ying Zhang , Yong-Qiang Yang , Jia-Kuo Yu
      Background The objectives of this study were to assess patellar morphology using computed tomography-based three-dimensional computer models and to determine the utility of the subchondral method for patellar resection in total knee arthroplasty (TKA). Methods Overall, 120 subjects (60 males, 60 females) from 20 to 50years old were included. Computer tomography images were used to construct 3D computer models of 240 knees. An anthropometric analysis of variance was used with the models to detect differences between the sides, age groups, and genders. Results Based on the available numbers, there were significant gender differences in the patellar length, width, and thickness even with strict control for the height and weight of the patients. The average patellar width/thickness ratio was 1.95, regardless of gender, and there was a good correlation between the patellar width and thickness (male: r=0.68, p<0.01; female: r=0.75, p<0.01). After using the subchondral method to virtually resect the patellae, the mean thickness for males and female was 14.0mm and 12.3mm, respectively. The proportion of the residual bony thickness that was less than 12mm was 5.83% (seven cases) in the male group and up to 42.5% (51 cases) in the female group. There was excellent intra-observer reliability and inter-observer reliability regarding the dimensional measurements in this study. Conclusions A robust method of measuring and virtually resecting the patella was established. The anthropometric dimensions of this study could provide basic data for guiding surgical management of the patella in TKA and are useful in designing patellar implants. Clinical relevance The anthropometric patellar information is essential for surgeons to perform patellar resurfacing in TKA.


      PubDate: 2015-06-26T12:42:54Z
       
  • The surgical management of symptomatic articular cartilage defects of the
           knee: Consensus statements from United Kingdom knee surgeons
    • Abstract: Publication date: Available online 23 June 2015
      Source:The Knee
      Author(s): Leela C. Biant , Michael J. McNicholas , Andrew P. Sprowson , Timothy Spalding
      Background Symptomatic articular cartilage and osteochondral lesions in the knee are an important source of pain and disability, and may lead to osteoarthritis. There are several surgical treatments for the condition, with emerging data evaluating their clinical effectiveness and longer-term clinical outcome. Health care providers have challenged the indications for the use of expensive techniques and have been reluctant to authorize funding or reimbursement. Methods The UK Cartilage Consensus Meeting was convened, involving clinicians in the UK with experience in the treatment options, decision-making and evaluation of the literature on the subject. Results This paper reports the consensus of attendees regarding appropriate surgical options for managing articular cartilage defects in the knee, validated by a large cohort of surgeons in the UK who are active in the field of articular cartilage surgery. Conclusions An evidence-based United Kingdom Consensus of 104 clinicians on the surgical management of symptomatic articular cartilage lesions of the knee. Several techniques may be suitable for small defects. Cell therapy has the best evidence-based outcomes for larger defects. Responsible innovation, pooled data collection and improvement in physical therapies are important. Surgeons should have access to the most appropriate evidence-based therapies for first-line treatment.


      PubDate: 2015-06-26T12:42:54Z
       
  • Effects of an unloader knee brace on knee-related symptoms and function in
           people with post-traumatic knee osteoarthritis after anterior cruciate
           ligament reconstruction
    • Abstract: Publication date: Available online 25 June 2015
      Source:The Knee
      Author(s): Harvi F. Hart , Kay M. Crossley , David C. Ackland , Sallie M. Cowan , Natalie J. Collins
      Background and purpose This pilot study evaluated the immediate and four-week effects of an unloader knee brace on knee-related symptoms and performance-based function in people with knee osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR). Methods Individuals with knee OA, five to 20years post-ACLR, were recruited for two within-subject randomized studies: immediate effects (n=18) and four-week effects (n=11). Patient-reported knee-related symptoms (knee pain, perceived task difficulty, confidence, stability) were assessed during hop for distance and step-down tests, while performance-based function was assessed with hopping distance under three conditions: i) no brace; ii) unadjusted brace (sagittal plane support); and iii) adjusted brace (sagittal plane support with varus/valgus readjustment). Participants in the four-week brace effect study were randomized to wear the unadjusted or adjusted brace for four weeks after baseline (no brace) testing, and repeated tests in their allocated brace at four-week follow-up. Friedman tests evaluated differences between the three brace conditions for each variable for the immediate brace effect study (p<0.05), and Wilcoxon signed-rank tests evaluated differences between no brace and allocated brace for the four-week study (p<0.05). Results The adjusted and unadjusted unloader braces produced immediate improvements in knee confidence during hop for distance, and knee pain during step-down. Following the four-week brace intervention, the allocated brace improved knee confidence, perceived task difficulty and stability during hop for distance; and knee pain, perceived task difficulty, confidence, and stability during step-down. Conclusions The unloader knee brace, adjusted or unadjusted, has the potential to improve knee-related symptoms associated with knee OA after ACLR.


      PubDate: 2015-06-26T12:42:54Z
       
  • Total knee arthroplasty using patient-specific guides: Is there a learning
           curve?
    • Abstract: Publication date: Available online 26 June 2015
      Source:The Knee
      Author(s): Jason Chinnappa , Darren B. Chen , Ian A. Harris , Samuel J. MacDessi
      Background Patient specific guides (PSG) have been reported to improve overall component alignment in total knee arthroplasty (TKA). With more surgeons likely to consider this method of TKA in the future, this study was performed to establish whether there is a learning curve with use of PSG in TKA. Methods Eighty-six consecutive PSG TKAs performed by one surgeon were retrospectively analyzed in two groups. The first 30 patients were compared to the second 56 patients with regards to their operative times and post-operative multi-planar alignments on computed tomography (CT) scan. Results Mean operative time was higher in the initial 30 cases compared to the second 56 cases (85min vs. 78min; p=0.001). No statistically significant differences were found in post-operative TKA alignment between the two groups. Conclusions This study suggests that there is a minimal learning curve with operative time associated with use of PSG in TKA. This study was unable to detect a significant learning curve with regards to restoration of mechanical knee alignment with the use of PSG in TKA. Level of Evidence: Level III, retrospective comparative study.


      PubDate: 2015-06-26T12:42:54Z
       
  • The UK National Ligament Registry Report 2015
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Ayman Gabr , Sean O'Leary , Tim Spalding , Steven Bollen , Fares Haddad



      PubDate: 2015-06-26T12:42:54Z
       
  • The Stiff Knee
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Hermann O. Mayr , Alfred Hochrein



      PubDate: 2015-06-26T12:42:54Z
       
  • Peri-operative practice in knee arthroscopy: A web-based survey of British
           Association for Surgery of the Knee (BASK) members
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Sujay Dheerendra , Ravi Pydisetty



      PubDate: 2015-06-26T12:42:54Z
       
  • British Association for Surgery of the Knee
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4




      PubDate: 2015-06-26T12:42:54Z
       
  • Instructions for Authors
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4




      PubDate: 2015-06-26T12:42:54Z
       
  • Lower limb alignment control: Is it more challenging in lateral compared
           to medial unicondylar knee arthroplasty?
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Saker Khamaisy , Brian P. Gladnick , Denis Nam , Keith R. Reinhardt , Thomas J. Heyse , Andrew D. Pearle
      Introduction Limb alignment after unicondylar knee arthroplasty (UKA) has a significant impact on outcomes. The literature lacks lateral UKA alignment studies, making our understanding of this issue based on medial UKA. Methods We evaluated limb alignment in 241 patients who underwent medial (229 knees) or lateral (37 knees) UKA. Alignment was measured pre and postoperatively in radiographs and intra-operatively using a navigation system. We compared the percentage of over-correction and the difference between post-operative alignment and navigation measurement. Results Percentage of overcorrection was significantly higher in the lateral UKAs (11%) compared to the medial UKAs (4%). In medial UKAs, the mean difference between the intraoperative alignment and the post-operative was 1.33°. This was significantly lower than the mean 1.86° difference in the lateral UKAs. Conclusions Our data demonstrated an increased risk of “overcorrection,” and greater difficulty in predicting postoperative alignment using computer navigation, when performing lateral UKAs compared to medial UKAs.


      PubDate: 2015-06-26T12:42:54Z
       
  • Role of magnetic resonance imaging in the diagnosis of the painful
           unicompartmental knee arthroplasty
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Caroline N. Park , Hendrik A. Zuiderbaan , Anthony Chang , Saker Khamaisy , Andrew D. Pearle , Anil S. Ranawat
      Background Unicompartmental knee arthroplasty (UKA) is a well established method for the treatment of single compartment arthritis; however, a subset of patients still present with continued pain after their procedure in the setting of a normal radiographic examination. This study investigates the effectiveness of magnetic resonance imaging (MRI) in guiding the diagnosis of the painful unicompartmental knee arthroplasty. Methods An IRB-approved retrospective review identified 300 consecutive UKAs performed over a three years period with 28 cases of symptomatic UKA (nine percent) with normal radiographic images. Results MRI examination was instrumental in finding a diagnosis that went undetected on radiographs. Based on MRI findings, 10 (36%) patients underwent surgery whilst 18 (64%) were treated conservatively. Conclusion This study supports the use of MRI as a valuable imaging modality for managing symptomatic unicompartmental knee arthroplasty. Level of evidence Case series


      PubDate: 2015-06-26T12:42:54Z
       
  • Modes of failure and revision of failed lateral unicompartmental knee
           arthroplasties
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Mustafa Citak , Michael B. Cross , Thorsten Gehrke , Kathrin Dersch , Daniel Kendoff
      Background Even with the resurgence of interest in unicompartmental knee arthroplasty (UKA) in recent years, lateral UKA is still performed 10 times less frequently than medial UKA. Hence, because of the infrequency of this procedure, a paucity of outcome studies exist on lateral unicompartmental knee arthroplasty. This retrospective study was performed to analyze the main causes of failure, as well as the time to failure following lateral UKA. Methods A total of 16 consecutive failed lateral UKAs were revised at our institution and were retrospectively reviewed. Causes of failure and time to failure were analyzed based on the medical records and radiographs at the time of revision. Results The mean time from index arthroplasty to revision surgery was 9.4years. In three cases, lateral UKA was converted to primary TKA and in the remaining thirteen cases, revision knee joint systems were used. Seven out of the 16 patients (43.8%) were revised within five years after the index surgery. Overall, the most common reason for failure was progression of arthritis of the medial and/or patellofemoral compartments (56.3%) followed by aseptic loosening (18.8%). Conclusions In conclusion, similar to published reports on medial UKA, the main reason for early and late failure after lateral UKA was progression of arthritis in other compartments. Level of evidence IV


      PubDate: 2015-06-26T12:42:54Z
       
  • The cemented twin-peg Oxford partial knee replacement survivorship: A
           cohort study
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Stephen H. White , Sharon Roberts , Jan Herman Kuiper
      Background A new twin-peg version of the Oxford knee was introduced in 2003. However, until now there has been no information about its survivorship. The aim of this study was to determine the survivorship, and the patients' perception of outcome over time. Methods A cohort of all patients treated from 2003 until 2009 using the twin-peg Oxford partial knee was contacted. The main indication for treatment was anteromedial osteoarthritis (AMOA). The Oxford Knee Score (OKS), American Knee Society Functional (AKS-F) score and satisfaction rate were obtained, and the time-to-failure was used to perform a survival analysis. Results There were 249 patients treated, with 288 medial cemented implants. Of these, 248 patients with 287 implants could be contacted and implant survival or failure was verified. Their mean age was 67years (range: 34–94). The mean follow-up time was 5.1years (maximum: 9.2). The nine years cumulative implant survival rate for all cases using revision for any reason to define failure was 98% (95% CI, 84 to 100). There were no cases of femoral loosening. The mean OKS was 22 pre-operatively, 41 at two years, and 41 at final review, at which point 96% of patients were very or fairly pleased with the result. Conclusion The survivorship of the twin-peg knee was better than that of the single peg knee at our centre, and appeared no worse than the results of the single peg knee at the originating centre. It can offer secure femoral fixation, sustained clinical benefit and patient satisfaction. Level of evidence Level IV case-series.


      PubDate: 2015-06-26T12:42:54Z
       
  • Factors influencing the outcome of deep infection following total knee
           arthroplasty
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Naoki Nakano , Tomoyuki Matsumoto , Kazunari Ishida , Nobuhiro Tsumura , Hirotsugu Muratsu , Takafumi Hiranaka , Ryosuke Kuroda , Masahiro Kurosaka
      Background Whereas clinical studies have revealed a number of important risk factors for postoperative infection following total knee arthroplasty (TKA), it is unclear which factor influences clinical results. A multicenter study was therefore performed by reviewing 51 patients with deep infection after TKA and seeking for the factors related to clinical outcomes. Methods Fifty-one deep infections after TKA were treated from 2000 to 2011 at the multicenter including a university or three arthroplasty centers. Among them, two clinical outcome measures including retention of prosthesis at initial treatment and functional prosthetic knee were assessed for several factors such as age, sex, primary diagnosis, onset time after primary TKA, type of hospital where the primary TKA was performed and the organism's resistance to methicillin using the logistic regression analysis model. Results Among the factors, type of hospital where the primary TKA was performed and onset time after primary TKA had higher multivariable-adjusted odds ratios (ORs) for retention of primary prosthesis (ORs 35.21 and 11.69, respectively.). The cases which primary surgery were performed in arthroplasty centers had higher multivariable-adjusted ORs for functional prosthetic knee (OR 4.9). Thirty-one infection cases with non-methicillin-resistant organisms were all able to keep functional prosthetic knee after the operation, whereas 13 out of 20 infection cases with methicillin-resistant organisms lost their knee function after the operation. Conclusions Onset time after primary TKA, type of hospital where the primary surgery was performed and the organism's resistance to methicillin are important factors influencing the clinical outcomes after infected TKA. Level of Evidence Level 3. Retrospective comparative study.


      PubDate: 2015-06-26T12:42:54Z
       
  • Prospective randomised trial comparing unlinked, modular bicompartmental
           knee arthroplasty and total knee arthroplasty: A five years follow-up
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Nicholas Eng Meng Yeo , Jerry Yongqiang Chen , Andy Yew , Shi-Lu Chia , Ngai Nung Lo , Seng Jin Yeo
      Background A significant proportion of patients with knee osteoarthritis have articular degeneration that is limited to the medial and patellofemoral compartments. The objective of this study was to compare clinical outcomes of unlinked bicompartmental knee arthroplasty (BCA) and total knee arthroplasty (TKA) at 5years in this subset of patients. Methods 48 patients were randomised into two groups: unlinked, modular bicompartmental arthroplasty and total knee arthroplasty. Data on demographics and clinical outcomes were collected (Bartlett Knee Score, Oxford Knee Score, Knee Society Score). Data on intra-operative blood loss in both groups were also recorded. Results Out of the 48 patients, 26 underwent BCA and 22 had TKA. Both groups shared similar demographic profiles. At five years post surgery, there was significant improvement across all functional scores in both groups. However, there was no significant difference in outcome scores in the BCA group compared to the TKA group. The drop in serum haemoglobin levels postoperatively was 1.55 and 2.30g/dl for the BCA and TKA groups respectively (p<.001). The total amount of blood loss was 397 and 647ml respectively (p=.001). Conclusions Unlinked, modular BCA results in similar clinical and functional scores as TKA for medial and patellofemoral arthritis in the mid-term. Intra-operative blood loss was significantly lower in the BCA group compared to the TKA group. BCA is a viable option for a select group of young and active patients with the advantage of reduced intra-operative blood loss and equivalent functional outcomes as TKA.


      PubDate: 2015-06-26T12:42:54Z
       
  • Rehabilitation following first-time patellar dislocation: A randomised
           controlled trial of purported vastus medialis obliquus muscle versus
           general quadriceps strengthening exercises
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): T.O. Smith , R. Chester , J. Cross , N. Hunt , A. Clark , S.T. Donell
      Background We aimed to define whether distal vastus medialis (VM) muscle strengthening improves functional outcomes compared to general quadriceps muscle strengthening following first-time patellar dislocation (FTPD). Methods Fifty patients post-FTPD were randomised to either a general quadriceps exercise or rehabilitation programme (n=25) or a specific-VM exercise and rehabilitation regime (n=25). The primary outcome was the Lysholm knee score, and secondary outcomes included the Tegner Level of Activity score, the Norwich Patellar Instability (NPI) score, and isometric knee extension strength at various knee flexion ranges of motion. Outcomes were assessed at baseline, six weeks, six months and 12months. Results There were statistically significant differences in functional outcome and activity levels with the Lysholm knee score and Tegner Level of Activity score at 12months in the general quadriceps exercise group compared to the VM group (p=0.05; 95% confidence interval (CI): −14.0 to 0.0/p=0.04; 95% CI: −3.0 to 0.0). This did not reach a clinically important difference. There was no statistically significant difference between the groups for the NPI score and isometric strength at any follow-up interval. The trial experienced substantial participant attrition (52% at 12months). Conclusions Whilst there was a statistical difference in the Lysholm knee score and Tegner Level of Activity score between general quadriceps and VM exercise groups at 12months, this may not have necessarily been clinically important. This trial highlights that participant recruitment and retention are challenges which should be considered when designing future trials in this population. Level of evidence Therapeutic study, Level I


      PubDate: 2015-06-26T12:42:54Z
       
  • Contralateral limb deficit seven months after ACL-reconstruction: An
           analysis of single-leg hop tests
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Benoît Pairot de Fontenay , Sebastien Argaud , Yoann Blache , Karine Monteil
      Background Following ACL-reconstruction, the non-injured leg (NIL) is used as a reference to assess injured leg (IL) recovery. However, deficits have been reported in the NIL questioning its use as a reference. The aim of this study is to assess whether NIL deficits are present while jumping after ACL-reconstruction. Methods Thirteen males who had undergone ACL-reconstruction and 16 healthy subjects took part in the experiment. Jumping performance was assessed during a single and a triple hop for distance. Jumping performance, kinematic and kinetic data were recorded during single leg squat jumps. Values for both the NIL and the IL were compared to those of a control group (CG). Results Jumping performance for single and triple hop for distance and single leg squat jump was lower in the NIL than in the CG (p=0.004, p=0.002, and p=0.016, respectively). During the squat jump, the knee joint was more extended and the ankle plantar-flexion was greater at take-off while the peak total moment was 15% lower in the NIL than in the CG (p=0.002, p=0.002, and p=0.009, respectively). We found consistent evolutions in the NIL and the IL compared to the CG for jumping performance, initial joint angles, and peak total moment during the squat jump, but the opposite was found for the ankle and knee joint angles at squat jump take-off. Conclusions Jumping strategies are impaired in the NIL after ACL-R during jump tasks with some deficits matching those observed in the IL and some specific to the NIL. Level of evidence III, Case control study


      PubDate: 2015-06-26T12:42:54Z
       
  • Does adjustable-loop femoral cortical suspension loosen after anterior
           cruciate ligament reconstruction? A retrospective comparative study
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Matthew J. Boyle , Tyler J. Vovos , Cameron G. Walker , Kathryne J. Stabile , Jonathan M. Roth , William E. Garrett Jr.
      Background Recent biomechanical research has suggested that adjustable-loop graft suspension constructs in anterior cruciate ligament (ACL) reconstruction may loosen after deployment. Our objective was to compare short-term knee stability and graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction. Methods A consecutive series of 188 patients who underwent primary ACL reconstruction using hamstrings autograft by a single surgeon were divided into two groups; 73 received adjustable-loop (TightRope RT (Arthrex Inc., Naples, FL)) and 115 received fixed-loop (RetroButton (Arthrex Inc., Naples, FL)) femoral cortical suspension. The two groups were compared at six months, one year, and two years postoperatively using KT-1000 arthrometer testing and graft failure rate (revision surgery, grade 2+ Lachman test, any pivot shift, >5mm side-to-side KT-1000 difference). Results There was no significant difference between the two groups in maximum side-to-side difference in KT-1000 testing at six months (mean 1.51mm (adjustable-loop group) vs. 1.79mm (fixed-loop group), p=0.23), one year (mean 1.44mm vs. 1.64mm, p=0.48), or two years (mean 1.14mm vs. 1.07mm, p=0.90) postoperatively. There was no significant difference between the two groups in rate of graft failure (10% vs. 11%, p=0.71) or timing of graft failure in affected patients (mean 11.4months vs. 13.8months, p=0.51). Conclusions We found no significant difference in postoperative knee stability or graft failure rate between adjustable-loop and fixed-loop femoral cortical suspension in patients undergoing primary ACL reconstruction. Our results suggest that adjustable-loop suspension does not clinically loosen after ACL reconstruction. Level of Evidence III (retrospective cohort study)


      PubDate: 2015-06-26T12:42:54Z
       
  • Sex differences in unilateral landing mechanics from absolute and relative
           heights
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Joshua T. Weinhandl , Bobbie S. Irmischer , Zachary A. Sievert
      Background The prevalence of anterior cruciate ligament injuries in athletic populations and the sex disparity in injury rates are well documented. It is also recognized that landing from a jump is a common noncontact injury mechanism. Yet, most studies utilize absolute landing heights, and few have utilized landing heights equal to participants' maximal jumping ability. The purpose of this study was to examine unilateral landing mechanics from relative and absolute heights. Methods Twenty-one female and twenty male participants completed a series of landings from absolute heights of 30, 40, and 50cm, as well as a height equal to their maximum jumping ability. Right leg three-dimensional kinematics, kinetics, and energetics were calculated from initial contact to maximum knee flexion. Results Females landed with greater peak posterior ground reaction force compared to males. Additionally, both female and male participants utilized the knee as the primary energy absorber, but females appear to emphasize greater ankle energy absorption compared to males. Females also displayed increased peak knee adduction moment, while males displayed decreased peak hip abduction moment as landing height increased. Conclusions It appears that females and males respond to increasing landing heights differently. However, landings from 40 and 50cm may have represented an unrealistic mechanical demand for females, and influence subsequent inferences regarding ACL injury risk. Therefore, we suggest that comparisons between studies utilizing different landing heights be made with caution, and participants jumping ability be taken into account whenever possible. Clinical relevance The findings of this study offer novel insights with regard to landing height and lower extremity mechanics with the potential to inform anterior cruciate ligament injury intervention programs.


      PubDate: 2015-06-26T12:42:54Z
       
  • Calculation of external knee adduction moments: A comparison of an inverse
           dynamics approach and a simplified lever-arm approach
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Ryan T. Lewinson , Jay T. Worobets , Darren J. Stefanyshyn
      Background The external knee adduction moment (EKAM) is often studied in knee osteoarthritis research. This study compared EKAMs between two methods of calculation: a method that only requires ground reaction force and knee position data (i.e. lever-arm), and an inverse dynamics link-segment method. Methods Sixteen participants walked while wearing a control shoe with and without a six millimeter lateral wedge insole. Peak EKAMs between the lever-arm and inverse dynamics methods were compared for the control condition, and the %change in moment induced by the lateral wedge was compared between methods. Results When comparing EKAMs between methods, no correlation was found (r =0.24, p =0.36); peak EKAMs with the lever-arm method (26.0Nm) were significantly lower than EKAMs with the inverse dynamics method (40.2Nm, pb0.001); and Bland–Altman plots showed poor agreement between methods. When assessing the %change in moment with a lateral wedge, a moderate correlation was found (r =0.55, p =0.03) between methods; Bland–Altman plots showed moderate agreement between methods; and the lever-arm method (−6.4%) was not significantly different from the inverse dynamics method (−11.4%, p =0.09); however, the two methods produced opposite results 31% of the time. Conclusion The lever-arm method cannot estimate peak EKAMs, and can only approximate the %change in moment induced by a lateral wedge; however, the error rate was 31%. Therefore, the lever-arm method is not recommended for use in its current form. Clinical relevance This study may help guide the development of a fast and simple method for determining EKAMs for individuals with knee osteoarthritis.


      PubDate: 2015-06-26T12:42:54Z
       
  • The cost of adverse events from knee surgery in the United Kingdom: An
           in-depth review of the National Health Service Litigation Authority
           database
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): A. Chen , N.K. Patel , Y. Khan , J.P. Cobb , C.M. Gupte
      Background There has been a significant rise in the number and value of claims against the National Health Service (NHS), with limited studies on litigation in orthopaedic surgery and none in knee surgery alone. We aimed to examine claims against the NHS involving all aspects of knee surgery with respect to costs and trends. Clinical relevance To raise awareness of the reasons for litigation in knee surgery, thus potentially improve patient care and reduce future claims. Methods We analysed the NHS litigation authority (NHSLA) database for all orthopaedic surgery claims reported to the NHSLA between 2005 and 2010, with calculation of litigation success rates and odds ratios for those relating to knee surgery. Results There were 515 cases identified from the 4609 orthopaedic cases in the NHSLA database (11.2%): 298 (58%) involving total knee replacements (TKRs), 11 (2%) involving unicondylar knee replacements, and 90 cases (30%) remaining open. The total pay out for closed cases was £10.45 million and amputation following TKR resulted in the highest single pay out. Litigation success rates for claimants were highest for retained drains (100%), incorrect prosthesis/prosthesis size (78%), renal failure (75%), poor outcome requiring further surgery (74%) and malalignment (71%). There were also 60 cases of delayed diagnosis which resulted in pay outs totalling £2.90 million. Based on these data, projected future pay out costs for the open TKR cases were estimated to be £2.71 million. Conclusion Litigation success rates for TKR were highest following technical errors such as malalignment compared to events less under the surgeon's control, such as infection. The number of claims involving incorrect prosthesis/size continues to be of concern. Despite the increased availability of imaging modalities, missed diagnosis also resulted in substantial pay outs.


      PubDate: 2015-06-26T12:42:54Z
       
  • Return to activity among athletes with a symptomatic bipartite patella: A
           systematic review
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): George T. Matic , David C. Flanigan
      Background A bipartite patella is typically rare, but can become symptomatic during overuse activities such as those performed during athletic events. Therefore, this anomaly typically presents in the young, athletic population, often inhibiting athletic activities. Multiple treatment options exist, with nonsurgical management frequently adopted as the initial treatment of choice. Purpose To determine the most effective intervention in returning athletes with symptomatic bipartite patella to their prior activity levels. Methods A systematic review of the literature was performed using PRISMA guidelines to identify studies reporting outcomes of athletes' ability to return to activity following treatment for a symptomatic bipartite patella. The type of intervention, type of bipartite classification, outcomes, and complications were recorded. Results Twenty articles with a total of 125 patients and 130 knees were identified and included in this review. A total of 105 athletes made a full return to athletic activity following treatment for their painful bipartite patella. One hundred athletes (85.5%) that underwent surgical treatment were able to make a full return to their sport without symptoms, although this varied by surgical procedure performed. Excision of the painful fragment produced the best results in returning athletes to sport, with 91% returning without symptoms and nine percent returning but with residual symptoms. Conclusion Surgical treatments for symptomatic bipartite patellae are successful at returning athletes to their same level of play, and best outcomes are with excision of the fragment. These results are limited, however, due to the poor quality of original data given the rarity of the anomaly and the underrepresented conservative treatment group.


      PubDate: 2015-06-26T12:42:54Z
       
  • Contents List
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4




      PubDate: 2015-06-26T12:42:54Z
       
  • Editorial Board
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4




      PubDate: 2015-06-26T12:42:54Z
       
  • Editorial
    • Abstract: Publication date: September 2015
      Source:The Knee, Volume 22, Issue 4
      Author(s): Caroline B. Hing , Jim B. Stiehl



      PubDate: 2015-06-26T12:42:54Z
       
  • In situ comparison of varying composite tibial tunnel interference screws
           used for ACL soft tissue graft fixation
    • Abstract: Publication date: Available online 16 June 2015
      Source:The Knee
      Author(s): John Nyland , Ryan Krupp , Joe Greene , Richard Bowles , Robert Burden , David N.M. Caborn
      Purpose This mechanical study using an in vitro porcine model compared composite interference screw fixation of soft tissue ACL grafts in tibial tunnels. Methods Forty-eight porcine profundus tendons and tibiae were divided into four groups of 12 closely matched specimens. Equivalent diameter grafts were assigned to each group. Tibial bone tunnels were drilled to 0.5mm greater than graft diameter. Grafts were fixed in tunnels using one 10×35mm composite interference screw designed by four different manufacturers. Maximal insertion torque and perceived within group mechanical testing outcome predictions were recorded. Constructs were potted and loaded into a six degrees of freedom clamp that placed the servohydraulic device tensile loading vector in direct tunnel alignment. Constructs were pre-loaded to 25N, pre-conditioned between 0 and 50N for 10cycles (0.5Hz), submaximally tested between 50 and 250N for 500cycles (one hertz) and load to failure tested at 20mm/min. Results Statistically significant differences were not observed between groups for displacement during submaximal cyclic loading, yield load, displacement at yield load, stiffness, ultimate load at failure and displacement at ultimate load. One composite screw group displayed a slightly greater proportion of specimens that required use of more than one screw during insertion. Conclusions Under highly controlled conditions groups displayed comparable fixation.


      PubDate: 2015-06-26T12:42:54Z
       
  • Tibiofemoral contact pressures in radial tears of the meniscus treated
           with all-inside repair, inside-out repair and partial meniscectomy
    • Abstract: Publication date: Available online 14 June 2015
      Source:The Knee
      Author(s): Alan L. Zhang , Stephanie L. Miller , Dezba G. Coughlin , Jeffrey C. Lotz , Brian T. Feeley
      Background To test contact pressures in the knee after treatment of a radial meniscus tear with an all-inside meniscal repair technique and compare the results with inside-out repair and partial meniscectomy. Methods Six non-paired cadaveric knees were analyzed with intra-compartment pressures measured at loads of 250N, 500N and 1000N at 0°, eight degrees, 15°, and 30° of knee flexion. Compartmental contact pressures were measured for the intact medial meniscus, radial tear in the posterior horn, all-inside repair using the NovoStitch suture passer device (Ceterix Orthopaedics Inc., Menlo Park, CA), inside-out repair method, and partial meniscectomy. One-way ANOVA was used for statistical analysis. Results The greatest differences in peak pressures between treatments were observed under 1000N load at 30° flexion (0.8±(SD)0.1MPa (intact meniscus), 0.8±(SD)0.1MPa (all-inside), 0.9±(SD)0.1MPa (inside-out) and 1.6±(SD)0.2MPa (partial meniscectomy)). Treatment with partial meniscectomy resulted in the highest peak pressures compared to all other states (p<0.0001 at each angle). Repair of the radial tear using the all-inside technique as well as the inside-out technique resulted in significantly decreased compartment pressures compared to partial meniscectomies (p<0.0001 at each angle). There were no significant differences between peak pressures in the intact state and after repair with the all-inside or inside-out techniques. Conclusion An all-inside repair technique using the NovoStitch suture passer can decrease contact pressures for a radial meniscus tear similarly to the inside-out repair technique when compared to partial meniscectomy. Clinical relevance This novel arthroscopic suture passer warrants further analysis in the clinical setting as it may be a reliable method for repair of radial meniscal tears through an arthroscopic all-inside technique.


      PubDate: 2015-06-26T12:42:54Z
       
  • Blastomycosis infection of the knee treated with staged total knee
           arthroplasty
    • Abstract: Publication date: Available online 13 June 2015
      Source:The Knee
      Author(s): Ian S. MacLean , Shandra R. Day , Christopher C. Moore , James A. Browne
      Blastomycosis is a rare fungal disease that can cause intraarticular infection and joint destruction requiring surgical reconstruction. We describe a patient who presented with destruction of the knee joint of unknown etiology. The patient was initially treated with debridement and spacer placement followed by antifungal therapy after cultures grew blastomycosis. Following adequate treatment of the infection, the patient was taken back to the operating room for reconstruction with a total knee arthroplasty. The patient had a successful outcome with no evidence of infection at two years following surgery. To our knowledge, this case report represents the first documented case in which a blastomycotic infection of a native knee was successfully treated with a two-stage total knee arthroplasty.


      PubDate: 2015-06-26T12:42:54Z
       
  • Erythropoietin stimulates patellar tendon healing in rats
    • Abstract: Publication date: Available online 9 June 2015
      Source:The Knee
      Author(s): Mustafa Uslu , Ertuğrul Kaya , Kürşat Oğuz Yaykaşlı , Murat Oktay , Mustafa Erkan Inanmaz , Cengiz Işık , Havva Erdem , Melih Engin Erkan , Hayati Kandiş
      Backround Erythropoietin (EPO), regulating erythropoiesis, is used to provide protective and regenerative activity in non-haematopoietic tissues. There is insufficient knowledge about the role of EPO activity in tendon healing. Therefore, we investigated the effect of EPO treatment on healing in rat patellar tendons. Methods One hundred and twenty-six, four-month-old male Sprague–Dawley rats were randomly assigned to three experimental groups: 1, no treatment; 2, treatment with isotonic saline (NaCl) and 3, treatment with EPO. Each group was randomly subdivided into two groups for sacrifice at three (1a, 2a, 3a) or sixweeks (1b, 2b, 3b). Complete incision of the left patellar tendon from the distal patellar pole was performed. We applied body casts for 20days after the incised edges of the patellar tendon were brought together with a surgical technique. Both legs were harvested and specimens from each group underwent histological, biomechanical, and protein mRNA expression analyses. Results There were statistically significant differences in the ultimate breaking force between the EPO group and others at both weeks three and six (p<0.05); significant differences in fibroblast proliferation, capillary vessel formation, and local inflammation were found between groups 1a and 3a, and 2a and 3a (p<0.05). There were statistical differences between 1a, 3a and 2a, 3a for Col III, TGF-β1, and VEGF and between 1b, 3b and 2b, 3b for Col I, Col III, TGF-β1, and VEGF mRNA expressions. Conclusion EPO had an additive effect with surgery on the injured tendon healing process in rats compared to the control groups biomechanically, histopathologically and with tissue protein mRNA expression. Clinical relevance This is the first experimental study to analyze the relationship between EPO treatment and the patellar tendon repair process by biomechanical, histopathological, and tendon tissue mRNA expression methodologies.


      PubDate: 2015-06-26T12:42:54Z
       
  • Post-operative bracing after ACL reconstruction has no effect on knee
           joint effusion. A prospective, randomized study
    • Abstract: Publication date: Available online 5 June 2015
      Source:The Knee
      Author(s): Maria Lindström , Torsten Wredmark , Marie-Louise Wretling , Marketta Henriksson , Li Felländer-Tsai
      Background It is unclear what factors contribute to knee joint effusion after anterior cruciate ligament (ACL) injury and reconstruction. Knee homeostasis after injury and surgery is crucial for rehabilitation and knee well-being. We examined if effusion was affected by post-operative bracing, and if patients with effusion fit into a common profile. Methods Patients were randomized to wearing or not wearing a post-operative brace for three weeks after ACL reconstruction with semitendinosus-gracilis tendons. Knee joint effusion was detected by computed tomography in 60 patients (22 women), before and three and 12months after surgery. Joint effusion, clinical and subjective tests were analyzed. Results This is the first prospective, randomized study on post-operative bracing for patients with a semitendinosus-gracilis graft showed that bracing had no effect on three-months presence of joint effusion. Excessive joint effusion was present in 68% of the patients three months after surgery and was associated to prior meniscus injury (p=0.05) and higher prior Tegner activity level (p=0.006). We found a positive association between longer time from injury to surgery and joint effusion three months post-operatively (rho=0.29, p<0.05). Twelve months post-operatively, joint effusion had diminished to baseline levels. Subjective scores and activity levels were lower for women. Three-months joint effusion predicted lower final outcome scores in women. Conclusion Prior meniscus injury and pre-injury Tegner activity levels are predictive significant variables for excessive knee joint effusion after ACL reconstruction. Post-operative bracing had no effect. A larger clinical cohort is needed to confirm findings of this logistic regression. Level of evidence I


      PubDate: 2015-06-26T12:42:54Z
       
  • Influence of mechanical unloading on histological changes of the patellar
           tendon insertion in rabbits
    • Abstract: Publication date: Available online 4 June 2015
      Source:The Knee
      Author(s): Hirotaka Mutsuzaki , Hiromi Nakajima , Yasuyoshi Wadano , Hikaru Takahashi , Masataka Sakane
      Background The purpose of this study was to clarify the influence of mechanical unloading on histological changes of the patellar tendon (PT) insertion in rabbits. Materials and methods The PT was completely released from stress by drawing the patella toward the tibial tubercle with a stainless steel wire installed between the patella and tibial tubercle (mechanical unloading group, n=28). The animals of the sham group underwent the same surgical procedure; however, the wire was not tightened (n=28). The average thickness of the Safranin O-stained glycosaminoglycan (GAG) area, chondrocyte apoptosis rate and chondrocyte proliferation rate of the cartilage layer at the insertion were measured at one, two, four, and sixweeks. Results The chondrocyte apoptosis rate in the mechanical unloading group was significantly higher than that in the sham group at one and fourweeks (p <0.05). The chondrocyte proliferation rate in the mechanical unloading group was significantly lower than that in the sham group at four and sixweeks (p <0.05). The average thickness of the GAG-stained area in the mechanical unloading group was significantly lower than that in the sham group at sixweeks (p <0.05). Conclusion Mechanical unloading significantly affected the increase in the chondrocyte apoptosis rate, decrease in the chondrocyte proliferation rate, and decrease in the GAG layer thickness at the PT insertion for up to sixweeks in rabbits. Clinical relevance We suggest that more than 6weeks of mechanical unloading should be avoided to prevent degeneration at the PT insertion.


      PubDate: 2015-06-26T12:42:54Z
       
  • Evaluating patient education material regarding unicompartmental knee
           arthroplasty
    • Abstract: Publication date: Available online 4 June 2015
      Source:The Knee
      Author(s): Kevin Wong , Rohith Mohan , Paul H. Yi , Erik N. Hansen
      Background Variability in quality and accuracy of information has been well documented in other orthopedic procedures. Given the growing role of the Internet in patient education, it is important to assess the quality of material provided. The purpose of this study was to evaluate online patient education materials regarding unicompartmental knee arthroplasty (UKA). Method The first 50 websites generated from a search of the term, partial knee replacement, using three search engines, Google, Yahoo!, and Bing, were analyzed for quality, content, and authorship. Categorical data between the three search engines were compared using the Freeman–Halton extension for the Fisher's exact test. Fisher's exact test was used to compare categorical data between the search terms partial knee replacement and unicompartmental knee arthroplasty. Results Most websites mentioned benefits of UKA (69%) but only a minority (39%) mentioned risks. A more technical search term, unicompartmental knee arthroplasty, yielded fewer websites authored by manufacturers/industry and miscellaneous sources (p=0.018 and p=0.039, respectively), more mentions of risks (p=0.0014), and more references to peer-reviewed literature (p=0.0026). Conclusions Overall, online information related to UKA is of questionable quality and may be geared more towards attracting patients than providing high-quality information.


      PubDate: 2015-06-26T12:42:54Z
       
  • The magnetic resonance aspect of a polyurethane meniscal scaffold is worse
           in advanced cartilage defects without deterioration of clinical outcomes
           after a minimum two-year follow-up
    • Abstract: Publication date: Available online 3 June 2015
      Source:The Knee
      Author(s): Pablo Eduardo Gelber , Alexandru Mihai Petrica , Anna Isart , Raquel Mari-Molina , Juan Carlos Monllau
      Background Meniscal scaffolding is thought to provide functional improvement and to prevent cartilage degeneration. Advanced chondral injuries might damage the scaffold structural properties. Objective To evaluate the influence of different degrees of articular chondral injuries on the imaging aspect of a polyurethane meniscal scaffold (Actifit®). Methods Fifty-four patients operated on with an Actifit® were studied. The status of the articular cartilage in the involved compartment was classified according to ICRS. The characteristics of the implant were evaluated in MRI with the Genovese score. Functional scores included WOMET, IKDC and Kujala scores. The Genovese score was correlated with the degree of chondral injury and functional results. Results The mean follow-up was 39months (range 25–63). Additional procedures were performed in 69.5%. There were 19 patients without chondral injuries and 14 with grade 1, 10 with grade 3 and eight with grade 4 chondral lesions. The morphology and size of the implant on MRI scanning were worse with a higher degree of chondral injury (p=0.023). WOMET, IKDC and Kujala improved from 36.2SD ±7.6, 32.3SD ±13.5 and 39.2SD ±8.1 to 75.8SD ±12.9 (p=0.02), 75.5SD ±15.4 (p=0.03) and 85.6SD ±13.4 (0.042), respectively. There was no relationship between the severity of chondral injury and functional scores. Conclusions Patients without chondral injuries showed a better MRI aspect of the polyurethane scaffold in terms of size and morphology. By optimizing biomechanics, in particular the implantation of a meniscal substitute, significant pain relief and functional improvement were observed after a minimum two-year follow-up. Level of evidence Therapeutic case series; level 4.


      PubDate: 2015-06-26T12:42:54Z
       
  • Lower limb kinematics of male and female soccer players during a
           self-selected cutting maneuver: Effects of prolonged activity
    • Abstract: Publication date: Available online 3 June 2015
      Source:The Knee
      Author(s): Andrew McGovern , Christopher Dude , Daniel Munkley , Thomas Martin , David Wallace , Richard Feinn , Donald Dione , Juan C. Garbalosa
      Background Despite the recent emphasis on injury prevention, anterior cruciate ligament (ACL) injury rates remain high. This study aimed to ascertain the effects of prolonged activity on lower limb kinematics during a self-selected cutting maneuver. Methods Angular kinematics were recorded during an agility test performed until the completion time was greater than the mean plus one SD of baseline trials. Cut type was identified and the hip and knee angles at 33 ms post heel strike were determined. A linear mixed effects model assessed the effects of cut type, gender, and activity status on the hip and knee angles. Results Males performed sidestep cuts more frequently than females. Females increased the incidence of sidestep cuts after prolonged activity. At the hip, a gender–cut type interaction existed for the transverse (p=0.001) and sagittal (p=0.11) planes. Females showed more internal rotation during sidestep and more external rotation and less flexion during crossover cuts. For the frontal plane, a gender–activity status interaction (p = 0.032) was due to no change within females but greater hip adduction during prolonged activity within males. With prolonged activity, both genders displayed less hip (p=0.29) and knee (p=0.009) flexion and more knee (p=0.001) adduction. Females displayed less hip and knee flexion than men (p=0.001). Conclusions Sidestep may be more risky than crossover cuts. Both genders place themselves in at-risk postures with prolonged activity due to less hip and knee flexion. Level of evidence Level 4


      PubDate: 2015-06-26T12:42:54Z
       
  • Contents List
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3




      PubDate: 2015-06-26T12:42:54Z
       
  • Editorial Board
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3




      PubDate: 2015-06-26T12:42:54Z
       
  • Editorial
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Caroline Hing



      PubDate: 2015-06-26T12:42:54Z
       
  • Reconstruction techniques and clinical results of patellar tendon
           ruptures: Evidence today
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Jack H. Gilmore , Zoë J. Clayton-Smith , Marc Aguilar , Spiros G. Pneumaticos , Peter V. Giannoudis
      Background The analysis of the different operative reconstructions of patellar tendon ruptures has not been reported. A critical review of the existing literature was performed to identify the different operative techniques and the post-operative outcomes in acute, chronic and post-total knee arthroplasty (TKA) patellar tendon rupture repairs. Methods Using PRISMA guidelines, a review of the English-written literature published after 1947 was performed using the MEDLINE, PubMed and Cochrane libraries in November 2013 to retrieve case series with the keywords “Patellar tendon” AND “Rupture” AND “Repair” in their title or abstract. Results Forty-one manuscripts, reporting on 503 patients were analysed. Three-hundred-and-fifty-four acute repairs described eight different operative techniques. One-hundred-and-forty-nine chronic repairs described eight different operative techniques. Sixty-eight post-TKA repairs described nine different operative techniques. Six acute, four chronic and seven post-TKA repair operative techniques reported failures. In acute repair, using a primary repair method augmented with cerclage wire, Dall–Miles cable or non-absorbable sutures reported the best clinical results, with a 2% failure rate. Alternatively, for chronic and post-TKA repair, autogeneous grafts were significantly better than primary repair (p=0.0252, 0.0038 respectively). Conclusion Acute surgical repair of a patellar tendon rupture using augmented primary repair is associated with the best post-operative outcomes. In chronic and post-TKA repair, autogeneous grafts produce best post-operative outcomes. Immediate post-operative mobilisation should be considered in all repairs. Future papers reporting on patellar operative repairs should have a standardised scoring method of functional outcome to allow more comprehensive comparison and evaluation.


      PubDate: 2015-06-26T12:42:54Z
       
  • Cartilage health in high tibial osteotomy using dGEMRIC: Relationships
           with joint kinematics
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Agnes G. d'Entremont , Robert G. McCormack , Kenard Agbanlog , Simon G.D. Horlick , Trevor B. Stone , Mojieb M. Manzary , David R. Wilson
      Purpose The aims of this study are to determine how opening-wedge high tibial osteotomy (HTO) affects cartilage health in the tibiofemoral (TF) joint and patella, and to explore relationships between TF and patellofemoral (PF) joint kinematics and cartilage health in HTO. Methods 14 knees (13 subjects) with medial TF osteoarthritis (OA) were examined before HTO and 6 and 12months after HTO using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) to evaluate cartilage health at the TF joint and patella. They were also examined using a validated 3D MR knee kinematics measurement to obtain 11 rotations and translations at both TF and PF joints. Results No statistically significant differences in overall TF or patellar dGEMRIC score were found at 6 or 12months after HTO. However three subjects had large decreases (mean 105ms) in TF dGEMRIC at 6months that recovered at 12months. Kinematics for these subjects were compared to subjects who did not have decreases in TF dGEMRIC at 6months (n =5). Differences were observed between groups with HTO in anterior and proximal tibial translation (mean differences 3.05mm and 1.35mm), and patellar flexion (mean difference 3.65°). These changes were consistent between 6 and 12months, despite recovery of TF dGEMRIC values. Conclusions We did not find significant differences in TF or patellar dGEMRIC before and after HTO with all subjects, however there were differences in kinematics between subjects who had a decrease in TF dGEMRIC at 6months and those who did not. This suggests a link between joint kinematics and cartilage health in HTO. Clinical relevance The effect of opening-wedge high tibial osteotomy on cartilage GAG concentration may be linked to specific changes in knee kinematics following surgery


      PubDate: 2015-06-26T12:42:54Z
       
  • Radiographic evaluation of complete and incomplete discoid lateral
           meniscus
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Jae Gwang Song , Jae Hwi Han , Jae Ho Kwon , Gautam M. Shetty , Leo Anthony M. Franco , Dae Young Kwon , Kyung Wook Nha
      Objectives The aim of this retrospective study was (1) to evaluate the radiographic features to differentiate arthroscopically confirmed complete and incomplete discoid lateral meniscus (DLM) (2) to determine the cutoff values for any parameter that was found to differentiate complete from incomplete DLM. Materials and Methods We retrospectively analyzed plain knee radiographs of 130 arthroscopically proven DLM. Seventy-nine patients had complete DLM and 51 patients incomplete DLM. Knee radiographs from 52 patients with arthroscopically proven normal lateral meniscus acted as control group. Radiographic parameters measured included fibular height, lateral joint space, condylar cutoff sign, height of lateral tibial spine, obliquity of lateral tibial spine, squaring of the lateral femoral condyle, and cupping of the lateral tibial plateau. Results Among radiographic parameters, high fibular head, widening of the lateral joint space and femoral condylar cutoff sign showed statistically significant (p<0.0001) differences between complete and incomplete DLM. At specific threshold points of fibular height<11mm, lateral joint space>6mm and condylar cutoff sign<0.80, the diagnosis of complete DLM revealed 87.3% sensitivity, 81.6% specificity and 78.4% positive predictive value (PPV) for the fibular height, 81.0% sensitivity, 86.6% specificity and 83.1% PPV for the lateral joint space, and 86.1% sensitivity, 83.5% specificity and 80% PPV for the condylar cutoff sign. Conclusions Radiographic features of fibular height, lateral joint space and condylar cut off sign can be used for screening of a complete type of DLM. However, radiographs are not a reliable screening tool for an incomplete DLM. Level of evidence IV, Case Series


      PubDate: 2015-06-26T12:42:54Z
       
  • Femoral footprint variation of the posterolateral bundle of the anterior
           cruciate ligament and double-bundle reconstruction
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Wei Lu , Weimin Zhu , Liangquan Peng , Wenzhe Fen , Hao Li , Yangkan Ou , Haifeng Liu , Daping Wang , Yanjun Zeng
      Background The study is aimed to observe the range of variation of the ACL PLB femoral footprint and investigate countermeasures for accurate femoral bone tunnel placement during double-bundle ACL reconstruction. Methods The femoral insertions of the anteromedial bundle (AMB) and PLB of the ACL were dissected in 30 male cadaveric knees. The ACL footprint on the lateral intercondylar wall (LIW) was observed, and the shape of the LIW, the resident ridge, the angle between the ACL long axis and femoral axis (AA), and the vertical distance from the center of the PLB to the lowest cartilage border of the LIW (PD) were measured. Results The area most populated by the ACL fibers was directly under the resident ridge. AA = 18.7°±15.25° with variation from –18° to 56°, and PD=7.02±1.47mm with variation from 3.75 to 11.08 mm. Both discrete values were very large in both groups of data. There were two kinds of LIW: trapezoidal (8 knees) and triangular (21 knees). Both AA and PD values exhibited significant differences between the two types of LIWs (P=0.00). Conclusion AA and PD vary among individuals. The insertions and centers of the PLB cannot be exactly anatomically determined with one size. For double-bundle ACL reconstruction, an individualized intraoperative footprint observation for fresh cases with footprint remnants, or resident ridge and anteromedial bundle-interval identification for old ACL tears, can be reasonable methods for posterolateral tunnel orientation. Clinical relevance Clinical relevance is observe the range of variation of the PLB femoral footprint for clinical double-bundle ACL reconstruction.


      PubDate: 2015-06-26T12:42:54Z
       
  • Update on the etiology of revision TKA — Evident trends in a
           retrospective survey of 1449 cases
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): Tilman Calliess , Max Ettinger , Natalie Hülsmann , Sven Ostermeier , Henning Windhagen
      Background A working and complete knowledge of the different causes of dysfunction and pain after TKA is essential for the ability to correctly determine the cause of failure and to address this problem specifically. The purpose of this study was to update the etiology of implant failure. New diagnosis and current trends should be displayed. Methods All TKA revisions performed in our institution between 2001 and 2010 were reviewed retrospectively. Patient demographics and the precise indication for the surgery were documented. Descriptive statistical analyses and association analyses of both the diagnosis and patient demographics were performed. Results Within our collective of 1449 revision TKA a total of 40 different pathologies leading to revision surgery were identified and categorized. Overall 68.5% of the revisions were categorized aseptic, 31.5% as septic implant failure. Some recently debated diagnoses like low-grade-infection showed a high increase in incidence whereas classic failure mechanisms like polyethylene wear showed a decrease over the time. Conclusion We believe that this study successfully updates the current knowledge of different failure mechanisms in revision TKA, which have to be considered on dysfunction or pain after surgery. We were able to evaluate the clinical relevance of each pathology and could shift from implant related problems like wear to more surgical problems like instability and or malalignment over the last years. With a higher alertness to chronic low-grade-infections the incidence of infection is even increasing. Level of evidence Level II, economic and decision analysis.


      PubDate: 2015-06-26T12:42:54Z
       
  • How accurate are orthopedic surgeons in diagnosing periprosthetic joint
           infection after total knee arthroplasty?: A multicenter study
    • Abstract: Publication date: June 2015
      Source:The Knee, Volume 22, Issue 3
      Author(s): In Jun Koh , Woo-Shin Cho , Nam Yong Choi , Javad Parvizi , Tae Kyun Kim
      Background The lack of standardized diagnostic criteria for periprosthetic joint infection (PJI) poses a challenge to accurate diagnosis of PJI. Recently, the Musculoskeletal Infection Society (MSIS) proposed diagnostic criteria for PJI. However, it is not known how well these proposed criteria accommodate real clinical scenarios. We determined what proportion of patients satisfied the MSIS criteria, and if MSIS criteria were not met, what other rationales were used to diagnose PJI. Methods We retrospectively reviewed the records of 303 patients who underwent two-stage exchange arthroplasty for treatment of PJI of the knee at 17 institutions. The rationale for making the diagnosis of PJI was also recorded, if the case did not meet the MSIS criteria. In addition, detailed information about isolated microorganisms were gathered. Results Among the 303 patients, 198 met the diagnostic criteria proposed by MSIS. Among the 105 patients who did not meet the MSIS criteria, 88% met two or three minor criteria; however joint fluid analysis or histologic analysis was not performed in 85% of these 105 patients. The most common rationale for the diagnosis of PJI was the presence of abnormal physical findings. Microorganisms were identified in only 52% of all patients; the most common organism was coagulase-negative Staphylococcus. Conclusions The diagnosis of PJI was based on clinical suspicion in approximately one-third of cases. In this series, joint aspiration or histological analysis was not performed in a large number of patients. Thus, surgeons should perform joint fluid and histologic analysis to assure the accuracy of PJI diagnosis.


      PubDate: 2015-06-26T12:42:54Z
       
  • The clinical effectiveness of self-care interventions with an exercise
           component to manage knee conditions: A systematic review
    • Abstract: Publication date: Available online 6 June 2015
      Source:The Knee
      Author(s): Kate Button , Paulien E. Roos , Irena Spasić , Paul Adamson , Robert W.M. van Deursen
      Objective Treatment of knee conditions should include approaches to support self-care and exercise based interventions. The most effective way to combine self-care and exercise has however not been determined sufficiently. Therefore the aim was to evaluate the clinical effectiveness of self-care programmes with an exercise component for individuals with any type of knee conditions. Methods A keyword search of Medline, CINAHL, Amed, PsycInfo, Web of Science, and Cochrane databases was conducted up until January 2015. Two reviewers independently assessed manuscript eligibility against inclusion/exclusion criteria. Study quality was assessed using the Downs and Black quality assessment tool and the Cochrane Risk of Bias Tool. Data were extracted about self-care and exercise intervention type, control intervention, participants, length of follow-up, outcome measures, and main findings. Results From the 7392 studies identified through the keyword search the title and abstract of 5498 were screened. The full text manuscripts of 106 studies were retrieved to evaluate their eligibility. Twenty-one manuscripts met the inclusion/exclusion criteria. Conclusion The treatment potential of combined self-care and exercise interventions has not been maximised because of limitations in study design and failure to adequately define intervention content. Potentially the most beneficial self-care treatment components are training self-management skills, information delivery, and goal setting. Exercise treatment components could be strengthened by better attention to dose and progression. Modern technology to streamline delivery and support self-care should be considered. More emphasis is required on using self-care and exercise programmes for chronic condition prevention in addition to chronic condition management.


      PubDate: 2015-06-07T06:15:02Z
       
 
 
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