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Journal Cover The Knee
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   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0968-0160
     Published by Elsevier Homepage  [2563 journals]   [SJR: 0.923]   [H-I: 38]
  • Coronal Alignment of Patellofemoral Arthroplasty
    • Abstract: Publication date: Available online 23 July 2014
      Source:The Knee
      Author(s): Emmanuel Thienpont , Jess H. Lonner
      Background Patellofemoral arthroplasty (PFA) can yield successful results in appropriately selected patients. The varus-valgus position or coronal alignment of the trochlear implant is determined by how its transitional edges articulate with the condylar cartilage. While variation in condylar anatomy will not influence the axis of the lower limb in PFA, it can impact the Q-angle of the PF joint. The aim of this study was to analyze how the coronal alignment can be influenced by the choice of anatomical landmarks. Materials and methods Retrospective analysis of 57 PFA with measurements of alignment on full leg radiographs. Results Coronal alignment following anterior condylar anatomy leads to a mean (SD) proximal valgus alignment of 100° (9°). Aligning the component with Whiteside's line gives a better alignment with less variance 89°(3°). Discussion A trochlear component with a higher Q-angle compensates for patellar maltracking if the condylar anatomy would tend to put the implant in a more proximal varus or neutral position. If the trochlear component is proximally aligned in valgus this may have the opposite effect. Aligning the trochlear component with the AP-axis in the coronal plane avoids maltracking and utilizes the design features of the implant at his advantage.


      PubDate: 2014-07-27T22:28:39Z
       
  • What predicts the first peak of the knee adduction moment?
    • Abstract: Publication date: Available online 24 July 2014
      Source:The Knee
      Author(s): Anne Schmitz , Brian Noehren
      Introduction The first peak of the knee adduction moment curve during walking has been shown to be a good clinical surrogate measure of medial tibiofemoral joint loading and osteoarthritis. Defining the relative contributions of the variables that dictate the knee adduction moment, such as center of mass, center of pressure, vertical ground reaction force, and knee adduction angle (i.e. lower limb alignment), has not been formally investigated within the same cohort of individuals. Purpose Therefore, the goal of this study was to determine which of these variables is the biggest determinant of the first peak of knee adduction moment curve. Methods Instrumented gait analysis was collected for 30 individuals. Variables significantly correlated with the peak knee adduction moment were input into a stepwise multi-variable linear regression model. Results The knee adduction angle predicted 58% of the variance in the first peak knee adduction moment and the vertical ground reaction force magnitude predicted the second most variance (20%). Conclusions The most effective way to modify the peak knee adduction moment may be to change the knee adduction angle (e.g. offloader brace), followed by changing the vertical magnitude of the ground reaction force (e.g. cane use).


      PubDate: 2014-07-27T22:28:39Z
       
  • Histological features of the ACL remnant in partial tears
    • Abstract: Publication date: Available online 24 July 2014
      Source:The Knee
      Author(s): Bertrand Sonnery-Cottet , Céline Bazille , Christophe Hulet , Philippe Colombet , Thomas Cucurulo , Jean Claude Panisset , Jean François Potel , Elvire Servien , Christophe Trojani , Patrick Djian , Nicolas Graveleau , Nicolas Pujol
      Purpose The aim of this study was to investigate the histological features of the remaining fibers bridging femur and tibia in partial ACL tears. Methods 26 ACL remnants were harvested from patients who had arthroscopic criteria concordant with a partial tear. Histological analysis includes cellularity, blood vessel density evaluation and characterization of the femoral bony insertion morphology. Immunohistochemical studies were carried out to determine cell positive for α-smooth actin and for mechanoreceptors detection. Results In this samples, a normal femoral insertion of the remnant was present in 22.7% of the cases. In 54 % of the samples, substantial areas of hypercellularity were observed. Myofibroblasts were the predominant cell type and numerous cells positive for α-smooth actin were detected at immunostaining. Blood vessel density was increased in hypercellularity areas and in the synovial sheet. Free nerve endings and few Golgi or Ruffini corpuscles were detected in 41 % of the specimens. The cellularity was correlated to the time between injury to surgery (p=.001). Conclusion Competent histological structures including a well vascularized synovial sheet, numerous fibroblasts and myofibroblasts and mechanoreceptors were found in ACL remnants. These histological findings bring additional knowledge towards the preservation of the ACL remnant in partial tears when ACL reconstruction or augmentation is considered.


      PubDate: 2014-07-27T22:28:39Z
       
  • Trochlear boss height measurement: A comparison of radiographs and MRI
    • Abstract: Publication date: Available online 24 July 2014
      Source:The Knee
      Author(s): J.W. MacKay , K.C. Godley , A.P. Toms , S.T. Donell
      Background A key anatomical consideration and determinant of surgical approach in trochlear dysplasia is the trochlear boss height (TBH), traditionally defined by measurements on plain x-rays (XR). Magnetic resonance (MR) imaging is increasingly used for pre-operative planning and follow-up. However, it is unclear whether measurement of TBH on XR is applicable to MR. The aim of this study was to establish the reliability of TBH measurement on MR compared to XR. Methods This study used lateral knee radiographs and MR scans of 14 knees of patients with trochlear dysplasia, six knees of non-dysplastic patients with anterior knee pain (AKP), and five knees of non-dysplastic controls with no AKP. Correlation between XR and MR measurements was assessed using Pearson correlation coefficients. Agreement between methods and observers was assessed using Bland-Altman plots with 95% limits of agreement. Intra- and inter- observer reliability was assessed using intraclass correlation coefficients (ICC). Results Bland-Altman charts showed a total width of 95% limits of agreement of 4.78mm for XR and MR subchondral bone (SB) TBH measurements, and 6.73mm for XR and MR cartilage TBH measurements. Inter-observer ICCs were 0.86 for XR, 0.62 for MR SB, and 0.53 for MR cartilage. The widths of the Bland-Altman 95% limits of agreement between observers were 4.79mm (XR), 5.04mm (MR SB) and 4.74mm (MR cartilage). Conclusion Measurement of TBH on MR is not directly interchangeable with XR. Adjustments need to be made to treatment thresholds based on XR measurement if MR is used instead.


      PubDate: 2014-07-27T22:28:39Z
       
  • Coronal Tibiofemoral Subluxation; A New Measurement Method
    • Abstract: Publication date: Available online 24 July 2014
      Source:The Knee
      Author(s): Saker Khamaisy , Hendrik A. Zuiderbaan , Ran Thein , Danyal H. Nawabi , Leo Joskowicz , Andrew D. Pearle
      Background Coronal tibiofemoral (CTF) subluxation is a common finding in knee osteoarthritis (OA) which can be related to poor pain scores and tibial spine impingement. In this study we describe a new method for measuring CTF subluxation and present validation of the method using cadaveric knees. Methods A prototype software code based on the ICP mathematical algorithm was developed to measure CTF subluxation; the code finds the rigid transformation that best aligns the articular surfaces, measures CTF subluxation and the angle between articular surfaces. For validation, three stripped fresh frozen cadaveric knee specimens were transfixed to a specially designed knee fixation device where tibiofemoral angle and CTF subluxation can be measured directly. Fluoroscopic images were obtained with the tibiofemoral joint in neutral alignment and with 5, 10 and 15 (mm) of medial and lateral subluxation. This procedure was repeated with a neutral tibiofemoral angle, 10° of varus, and 10° of valgus. All images were analyzed independently by two investigators using the prototype software. Results The interclass correlation coefficient between the two investigators for CTF subluxation and tibiofemoral angle was 0.93 and 0.99 respectively. The CTF subluxation and tibiofemoral angle measured by the software correlated to the CTF subluxation and tibiofemoral angle defined using the knee fixation device, with Pearson product moments of 0.86 and 0.94 respectively. Conclusion Our suggested prototype software is precise, repeatable and reliable at measuring CTF subluxation and tibiofemoral angle. It may prove to be a useful tool to evaluate CTF subluxation in a clinical setting.


      PubDate: 2014-07-27T22:28:39Z
       
  • Management of extreme patella baja using in-situ hamstring tendon
           autograft
    • Abstract: Publication date: Available online 16 June 2014
      Source:The Knee
      Author(s): L.S. Moulton , A.P. Davies
      Successful total knee arthroplasty requires a functioning extensor mechanism. Patella baja following total knee arthroplasty can cause extensor mechanism dysfunction and produce poor outcomes. We present a case of severe patella tendon shortening following revision total knee arthroplasty with almost complete ankylosis of the distal pole of the patella to the proximal tibia. This resulted in effective extensor mechanism dysfunction with pain and severely limited knee flexion. We report a novel method of reconstruction of the patella tendon at the time of revision arthroplasty together with the one-year clinical outcome and review of the literature.


      PubDate: 2014-07-27T22:28:39Z
       
  • A prospective double blinded randomized study of anterior cruciate
           ligament reconstruction with hamstrings tendon and spinal anesthesia with
           or without femoral nerve block
    • Abstract: Publication date: Available online 16 June 2014
      Source:The Knee
      Author(s): Diego Costa Astur , Vinicius Aleluia , Ciro Veronese , Nelson Astur , Saulo Gomes Oliveira , Gustavo Gonçalves Arliani , Ricardo Badra , Camila Cohen Kaleka , Joicemar Tarouco Amaro , Moisés Cohen
      Background Current literature supports the thought that anesthesia and analgesia administered perioperatively for an anterior cruciate ligament (ACL) reconstruction have a great influence on time to effective rehabilitation during the first week after hospital discharge. Purpose The aim of this study is to answer the research question is there a difference in clinical outcomes between the use of a femoral nerve block with spinal anesthesia versus spinal analgesia alone for people undergoing ACL reconstruction? Methods ACL reconstruction with spinal anesthesia and patient sedation (Group one); and spinal anesthesia with patient sedation and an additional femoral nerve block (Group two). Patients were re-evaluated for pain, range of motion (ROM), active contraction of the quadriceps, and a Functional Independence Measure (FIM) scoring scale. Results Spinal anesthesia with a femoral nerve block demonstrates pain relief 6h after surgery (VAS 0.37; p =0.007). From the third (VAS=4.56; p =0.028) to the seventh (VAS=2.87; p =0.05) days after surgery, this same nerve blockage delivered higher pain scores. Patients had a similar progressive improvement on knee joint range of motion with or without femoral nerve block (p <0.002). Group one and two had 23.75 and 24.29° 6h after surgery and 87.81 and 85.36° of knee flexion after 48h post op. Conclusion Spinal anesthesia associated with a femoral nerve block had no additional benefits on pain control after the third postoperative day. There were no differences between groups concerning ability for knee flexion and to complete daily activities during postoperative period. Level of Evidence Randomized Clinical Trial Level I.


      PubDate: 2014-07-27T22:28:39Z
       
  • Knee joint laxity and passive stiffness in meniscectomized patients
           compared with healthy controls
    • Abstract: Publication date: Available online 16 June 2014
      Source:The Knee
      Author(s): Jonas B. Thorlund , Mark W. Creaby , Tim V. Wrigley , Ben R. Metcalf , Kim L. Bennell
      Background Passive mechanical behavior of the knee in the frontal plane, measured as angular laxity and mechanical stiffness, may play an important role in the pathogenesis of knee osteoarthritis (OA). Little is known about knee laxity and stiffness prior to knee OA onset. We investigated knee joint angular laxity and passive stiffness in meniscectomized patients at high risk of knee OA compared with healthy controls. Methods Sixty patients meniscectomized for a medial meniscal tear (52 men, 41.4±5.5years, 175.3±7.9cm, 83.6±12.8kg, mean±SD) and 21 healthy controls (18 men, 42.0±6.7years, 176.8±5.7cm, 77.8±13.4kg) had their knee joint angular laxity and passive stiffness assessed twice ~2.3years apart. Linear regression models including age, sex, height and body mass as covariates in the adjusted model were used to assess differences between groups. Results Greater knee joint varus (−10.1 vs. −7.3°, p<0.001), valgus (7.1 vs. 5.6°, p=0.001) and total (17.2 vs. 12.9°, p<0.001) angular laxity together with reduced midrange passive stiffness (1.71 vs. 2.36Nm/°, p<0.001) were observed in patients vs. healthy controls. No differences were observed in change in stiffness over time between patients and controls, however a tendency towards increased laxity in patients was seen. Conclusions Meniscectomized patients showed increased knee joint angular laxity and reduced passive stiffness ~3months post surgery compared with controls. In addition, the results indicated that knee joint laxity may increase over time in meniscectomized patients.


      PubDate: 2014-07-27T22:28:39Z
       
  • Frontal plane knee mechanics and medial cartilage MR relaxation times in
           individuals with ACL reconstruction: A pilot study
    • Abstract: Publication date: Available online 20 June 2014
      Source:The Knee
      Author(s): Deepak Kumar , Abbas Kothari , Richard B. Souza , Samuel Wu , C. Benjamin Ma , Xiaojuan Li
      Background The objective of this pilot study was to evaluate cartilage T1ρ and T2 relaxation times and knee mechanics during walking and drop-landing for individuals with anterior cruciate ligament reconstruction (ACL-R). Methods Nine patients (6 men and 3 women, age 35.8±5.4years, BMI 23.5±2.5kg/m2) participated 1.5±0.8years after single-bundle two-tunnel ACL reconstruction. Peak knee adduction moment (KAM), flexion moment (KFM), extension moment (KEM), and peak varus were calculated from kinematic and kinetic data obtained during walking and drop-landing tasks. T1ρ and T2 times were calculated for medial femur (MF), and medial tibia (MT) cartilage and compared between subjects with low KAM and high KAM. Biomechanical variables were compared between limbs. Results The high KAM group had higher T1ρ for MT (p=0.01), central MT (p=0.05), posterior MF (p=0.04), posterior MT (p=0.01); and higher T2 for MT (p=0.02), MF (p=0.05), posterior MF (p=0.002) and posterior MT (p=0.01). During walking, ACL-R knees had greater flexion at initial contact (p=0.04), and lower KEM (p=0.02). During drop-landing, the ACL-R knees had lower KAM (p=0.03) and KFM (p=0.002). Conclusion Patients with ACL-R who have higher KAM during walking had elevated MR relaxation times in the medial knee compartments. These data suggest that those individuals who have undergone ACL-R and have higher frontal plane loading, may be at a greater risk of knee osteoarthritis.


      PubDate: 2014-07-27T22:28:39Z
       
  • Comparison of the ceiling effect in the Lysholm score and the IKDC
           subjective score for assessing functional outcome after ACL reconstruction
           
    • Abstract: Publication date: Available online 21 June 2014
      Source:The Knee
      Author(s): Ho Jong Ra , Hyoung Soo Kim , Jung Yun Choi , Jeong Ku Ha , Ji Yeong Kim , Jin Goo Kim
      Background To compare the ceiling effect of the Lysholm and IKDC subjective scores for assessing functional outcome after ACL reconstruction and evaluated the correlation with the one-leg hop test. Methods A total of 134 patients who underwent ACL reconstruction between 2007 and 2011 were enrolled in this study. All patients fulfilled the postoperative 6- and 12-month evaluations. The ceiling effect of the Lysholm and IKDC subjective scores was assessed, and the correlations between two scales and one-leg hop test were analysed. Results For the entire sample, the ceiling effect for the Lysholm score was 14.9% and 30.6% at 6 and 12months postoperatively. The values for the IKDC subjective score were 5.2% and 17.2%, respectively. In all subjects, the correlation coefficients [95% confidence intervals] between the IKDC subjective score and one-leg hop test at 6 and 12months (r =0.492, [0.34 to 0.62]; r =0.296, [0.12 to 0.46]) were higher than those for the Lysholm score (r =0.355, [0.18 to 0.51]; r =0.241, [0.06 to 0.41]), respectively.(p <0.05). Conclusion With regard to evaluating ACL reconstruction outcomes in patients, no significant difference between the IKDC subjective and the Lysholm scores exists in terms of the amount of ceiling effect and the correlation with the LSI. However, the concern that the ceiling effect of the Lysholm score was greater than the IKDC subjective score, should be addressed in assessing the patient's functional status postoperatively. Level of evidence: III, retrospective comparative study.


      PubDate: 2014-07-27T22:28:39Z
       
  • A Meta-analysis of Anterior Cruciate Ligament Reconstruction with
           Autograft Compared with Non-irradiated Allograft
    • Abstract: Publication date: Available online 30 June 2014
      Source:The Knee
      Author(s): Jie Wei , Hao-bin Yang , Jia-bi Qin , Tu-bao Yang
      Purpose To compare autograft with non-irradiated allograft for reconstruction of anterior cruciate ligament. Methods MEDLINE, EMBASE, Cochrane Library databases, as well as unpublished and ongoing studies were searched through up to 20 July 2013 to identify studies meeting the pre-stated inclusion criteria. Results A total of twelve studies (n=1,167, including 597 patients in the autograft group and 570 patients in the allograft group) were included. The methodological scores for randomized controlled trials ranged from 2 to 4 (total score: 7), and for non-randomized prospective studies and cohort studies ranged from 4 to 7 (total score: 12). Except for the Lysholm score (WMD, −1.46; P<0.05) showed a statistically significant difference but a small and clinically irrelevant difference, there was no significant difference between autograft and non-irradiated allograft with respect to the overall IKDC (International Knee Documentation Committee) level, subjective IKDC score, Tegner score, complication, ROM (range of motion), Pivot-shift test, Anterior drawer test, Lachman test, Daniel’s 1-leg hop test, Harner’s vertical jump test, and Instrumented knee laxity test. The results were consistent across a series of sensitivity analyses and subgroup analyses. Conclusions Patients with autograft exhibited little clinical advantage over non-irradiated allograft with respect to knee stability, function and side effects. The robustness of the findings might need to be further validated due to the relatively small number of randomized controlled trials. Level of evidence Level II, meta-analysis of prospective studies


      PubDate: 2014-07-27T22:28:39Z
       
  • Alignment of the tibial component of the unicompartmental knee
           arthroplasty, assessed in the axial view by CT scan: Does it influence the
           outcome?
    • Abstract: Publication date: Available online 8 July 2014
      Source:The Knee
      Author(s): I. Iriberri , J.F. Aragón
      Background The ideal position of the unicompartmental knee arthroplasty (UKA) in the axial plane remains undefined in medical literature. The aim of this study was to observe how tibial components are placed in the axial plane and identify whether this could influence the postoperative clinical outcome. Methods Retrospective transversal study of 101 UKA performed in 88 patients by a single surgeon. Postoperative CT scans were performed at a mean follow-up period of 71months (36 to 150) and clinical and functional outcomes were assessed by the WOMAC and the KSS scores. Patients were divided several times in two groups depending on a different WOMAC or KSS value each time and differences in axial angulation were analysed in every comparison. Distribution of data and influence on outcomes were also analysed. Results The tibial component was positioned with a mean angulation of 11.9° (-1 to 32) of external rotation (ER). A lower angle of ER was observed in all comparisons in the groups with better outcomes. Differences between groups were statistically significant when a good result was defined as a WOMAC score lower than 10. Conclusions Variability in axial positioning (33°) is higher than in other planes due to the free-hand technique. A trend towards better outcomes is observed when the tibial component is placed in a lower angle of ER. Rotational alignment in UKA should be investigated in subsequent studies with larger sample sizes. Level Of Evidence Level III, retrospective comparative study


      PubDate: 2014-07-27T22:28:39Z
       
  • Five-year follow-up of Minimally Invasive Computer Assisted Total Knee
           Arthroplasty (MICATKA) versus conventional Computer Assisted Total Knee
           Arthroplasty (CATKA) – a population matched study
    • Abstract: Publication date: Available online 2 July 2014
      Source:The Knee
      Author(s): R.S. Khakha , M. Chowdhry , M. Norris , A. Kheiran , N. Patel , S.K. Chauhan
      Introduction Minimally invasive surgery (MIS) has perceived advantages in the early post-operative stage such as reduced blood loss, decreased pain, earlier return to function and earlier discharge. Objective The aim of our study was to confirm that longer term clinical outcome of TKA is not compromised when MIS is combined with computer assisted surgery. Methods Eighty patients matched for age, gender, pre-operative Knee Society Score (KSS) and mechanical axis, were prospectively studied. Forty underwent minimally invasive computer assisted total knee arthroplasty (MICATKA) and 40 conventional computer assisted TKA (CATKA). Functional scores were determined at 6weeks, 6, 12, 18, 24month and 5years post surgery. Long-leg alignment views were obtained 3months post-operatively. Results KSS Scores in the short term were significantly better in the MICATKA compared to CATKA group (p<000.1). Tourniquet-time was 58min in MICTKA and 60min in CATKA group (p=0.3). Straight leg raise was achieved by day one in 93% of the MICATKA compared to 30% of the CATKA (p<0.001). Length of stay for MICATKA was a mean of 3.25days with CATKA a mean of 6days (p<0.001). KSS scores up to 2-years were significantly better in the MICTKA group (p<0.001). At 5-years there was no significant difference in the MICATKA and CATKA in KSS Scores (p=0.46). Conclusion We confirm that the use of navigation in minimally invasive TKA permits a number of early post-operative advantages and that longer-term functional outcome is not compromised with its usage.


      PubDate: 2014-07-27T22:28:39Z
       
  • Tibial Component Rotation: The Inveterate Problem
    • Abstract: Publication date: Available online 12 July 2014
      Source:The Knee
      Author(s): Henry D. Clarke



      PubDate: 2014-07-27T22:28:39Z
       
  • Relationship of the Posterior Femoral Axis of the “Kinematically
           Aligned” Total Knee Arthroplasty to the Posterior Condylar,
           Transepicondylar, and Anteroposterior Femoral Axes
    • Abstract: Publication date: Available online 24 July 2014
      Source:The Knee
      Author(s): Andrew Park , Stephen T. Duncan , Ryan M. Nunley , James A. Keeney , Robert L. Barrack , Denis Nam
      Background A recent proposed modification in surgical technique in total knee arthroplasty (TKA) has been the introduction of the “kinematically aligned” TKA, in which the angle and level of the posterior joint line of the femoral component and joint line of the tibial component are aligned to those of the “normal,” pre-arthritic knee. The purpose of this study was to establish the relationship of the posterior femoral axis of the “kinematically aligned” total knee arthroplasty (TKA) to the traditional axes used to set femoral component rotation. Methods 114 consecutive, unselected patients with preoperative MRI images undergoing TKA were retrospectively reviewed. The transepicondylar axis (TEA), posterior condylar axis (PCA), antero-posterior axis (APA) of the trochlear groove, and posterior femoral axis of the kinematically aligned TKA (KAA) were templated on axial MRI images by two, independent observers. The relationships between the KAA, TEA, APA, and PCA were determined, with a negative value indicating relative internal rotation of the axis. Results On average, the KAA was 0.5° externally rotated relative to the PCA (minimum of −3.6°, maximum of 5.8°), −4.0° internally rotated relative to the TEA (minimum of −10.5°, maximum of 2.3°), and −96.4° internally rotated relative to the APA (minimum of −104.5°, maximum of −88.5°). Each of these relationships exhibited a wide range of potential values. Conclusions Using a kinematically aligned surgical technique internally rotates the posterior femoral axis relative to the transepicondylar axis, which significantly differs from current alignment instrument targets.


      PubDate: 2014-07-27T22:28:39Z
       
  • In vivo evaluation of femoral and tibial graft tunnel placement following
           all-inside arthroscopic tibial inlay reconstruction of the posterior
           cruciate ligament
    • Abstract: Publication date: Available online 15 July 2014
      Source:The Knee
      Author(s): Michael Osti , Alessa Krawinkel , Karl Peter Benedetto
      Background Arthroscopic all-inside tibial inlay technique represents a novel procedure for posterior cruciate ligament (PCL) reconstruction. However, in vivo investigations that evaluate the accuracy of this technique regarding anatomic graft tunnel placement are lacking. The objective of this study was to analyse the femoral and tibial tunnel entry using computed tomography (CT) and compare these findings to recommendations in literature. Methods CT scans were obtained in 45 patients following single-bundle PCL reconstruction. The centres of the tibial and femoral tunnel apertures were correlated to measurement grid systems used as a radiographic reference. Results The centre of the femoral tunnel aperture was located at 42.9 %±9.4 % of the total intercondylar depth and at 12.9 %±7.2 % of the total intercondylar height. The angle α for the femoral tunnel position was measured at 64.2°±10.0°. The centre of the tibial tunnel aperture was found at 51.8 %±4.1 % of the total mediolateral diameter of the tibial plateau. The superoinferior distance of the tibial tunnel aperture to the joint line was 9.6mm±4.4mm on frontal and 9.3mm±3.4mm on sagittal 3D-CT scans. The distance of the tibial tunnel aperture to the former physis line averaged to 0.8mm±3.4mm. Comparison to the corresponding reference values revealed no statistically significant difference. Conclusion Arthroscopic tibial inlay reconstruction is an efficient procedure for precise replication of the anatomical footprint of the PCL. Level of evidence IV, prospective case series


      PubDate: 2014-07-27T22:28:39Z
       
  • Root avulsion of the posterior horn of the medial meniscus in skeletally
           immature patients
    • Abstract: Publication date: Available online 15 July 2014
      Source:The Knee
      Author(s): Bertrand Sonnery-Cottet , Rafael Mortati , Pooler Archbold , François Gadea , Julien Clechet , Mathieu Thaunat
      Meniscal root avulsion has been predominantly reported in an adult population but little is known about this meniscal lesion in children and adolescents. The purpose of this article is to describe the clinical symptoms and a new MRI sign of a medial meniscus posterior root avulsion in skeletally immature patients, and to report the arthroscopic procedure for its reinsertion in presence of open physes. We report the cases of two skeletally immature patients who had a medial meniscus posterior root avulsion [MMPRA]. Diagnosis of a MMPRA was suspected on MRI by intense T2 hypersignal located at the postero-medial part of the tibial plateau reflecting a trabecular bone oedema (“Bone bruise”) at the level of the medial meniscal posterior root attachment. Arthroscopic reduction and fixation of the posterior root of medial meniscus with transosseous sutures was performed. The patients returned to sport at the end of the 6months without residual symptoms. At one year, the radiographs showed no modification of the physis. Healing of the medial meniscal posterior root was noted on MRI. In a skeletally immature patient it is important that this rare meniscal lesion is diagnosed early and adequately treated. We emphasize the importance of the indirect MRI signs that can lead a clinician to suspect the diagnosis of MMPRA. The aim of the surgery was to restore the anatomical footprint of the meniscal root and to re-establish its function thus preventing future chondral damage without damage to the tibial physeal growth plate. Level of evidence: Level IV


      PubDate: 2014-07-27T22:28:39Z
       
  • Arthroscopic BPTB Graft Reconstruction in ACL Ruptures: 15-year Results
           and Survival
    • Abstract: Publication date: Available online 15 July 2014
      Source:The Knee
      Author(s): E. Carlos Rodríguez-Merchán , David Durán , Carlos Revilla , Primitivo Gómez-Cardero , Ángel Martínez-Lloreda , Santiago Bello
      Purpose To investigate the 15-year results and survival of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft Methods ACL BPTB reconstruction was performed in 250 consecutive patients. Of these patients, 88% returned for a follow-up examination at 15years after reconstruction. Therefore, 220 patients were studied. Mean time from injury to intervention was 3.4months (range 2 to 16). The parameters for assessment of results were subjective satisfaction, clinical examination (pivot-shift test, Lachman test with KT-1000), recovery of pre-injury activity level, and long-standing X-rays. We also evaluated the presence of meniscal and/or chondral injuries during the procedure. Failure rates were also evaluated. We defined a failure as severe instability not compatible with the activities of daily living (ADL) due to graft rupture. Results 8.2% of patients required a revision procedure because of graft rupture. In subjective terms, 98.1% of patients said they were satisfied with the surgical outcomes after 15years. Pivot shift test was normal in 93.5% at 15years. Lachman test (KT-1000) was normal in 95.4% at 15years. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15years. Conclusions The survival prevalence of arthroscopic ACL reconstruction using the central-third patellar bone-tendon-bone (BPTB) autograft at 15years was 94.8%. Fifteen years after surgery, 90% of patients recovered their pre-injury activity level. In 25.4% of patients symptomatic osteoarthritic changes in the knee were found at 15years.


      PubDate: 2014-07-27T22:28:39Z
       
  • Prepatellar Continuation Rupture; Report of an Unusual Case
    • Abstract: Publication date: Available online 19 July 2014
      Source:The Knee
      Author(s): Haroon Majeed , Ian dos Remedios , Praveen Datta , David Griffiths
      In anatomical studies the deepest soft tissue layer, related to the deep rectus femoris tendinous fibers, has been described as the “prepatellar quadriceps continuation”. We present an unusual case of an isolated prepatellar continuation rupture, which to our knowledge is the first described case in the literature. Injuries to the extensor mechanism may include isolated rupture of the prepatellar continuation with intact quadriceps and patellar tendons. Diagnosis may be difficult with ultrasound scan and requires MRI scan for confirmation. Appropriate clinical assessment and regular physiotherapy leads to a full functional recovery.


      PubDate: 2014-07-27T22:28:39Z
       
  • Radiodense ligament markers for radiographic evaluation of anterior
           cruciate ligament reconstruction
    • Abstract: Publication date: Available online 23 July 2014
      Source:The Knee
      Author(s): Paul Borbas , Karl Wieser , Stefan Rahm , Sandro F. Fucentese , Peter P. Koch , Dominik C. Meyer
      Introduction Early clinical and radiographic diagnosis of failed or loosened anterior cruciate ligament (ACL) reconstructions can be challenging. The aim of the present study is to retrospectively evaluate the use of radiologically visible markers in the ACL graft, serving as a potential diagnostic tool in ACL graft rupture and insufficiency. Methods Twenty patients were included in the study. ACL reconstruction was performed with use of a hamstring autograft in hybrid fixation technique. The graft was marked with two radiodense suture knots, one at tibial and femoral tunnel opening. X-rays were performed postoperatively, after 6weeks and 12months. Four distances between markers and landmarks were measured in anteroposterior and three in lateral x-ray views and the positional change between the timepoints of measurement was calculated. Results Measurements of the marker distances on x-rays showed an excellent interobserver reliability (κ=0.97). In two measured distal anteroposterior distances statistically significant changes could be detected between 6weeks and 12months postoperatively in one patient with MRI-documented ACL rerupture and in five patients with ACL elongation defined as anteroposterior-translation with side-to-side difference of≥3mm measured with a Rolimeter device. In lateral x-rays, marker distances were highly variable and did not correlate with clinical ACL elongation. Conclusion The application of radiodense ACL graft markers is a straight-forward, non-expensive and potentially useful diagnostic tool to identify the position of the transplant and for diagnosis of graft elongation or failure. However, the method is sensitive to the radiological projection, which should be further studied and optimized.


      PubDate: 2014-07-27T22:28:39Z
       
  • Bristol Index of Patella Width to Thickness (BIPWiT): a reproducible
           measure of patella thickness from adult MRI
    • Abstract: Publication date: Available online 23 July 2014
      Source:The Knee
      Author(s): N.P.T. Sullivan , P.W. Robinson , A. Ansari , M. Hassaballa , J.R. Robinson , A.J. Porteous , J.D. Eldridge , J.R.D. Murray
      Background The restoration of an adequate patella thickness is key to the successful outcome of knee arthroplasty. This study investigated the relationship between the thickness of the native patella and medial-lateral patella width using magnietic resonance imaging (MRI). Methods 75 MRI scans of young adults, average age 27 (range 16–40) were studied. Exclusion criteria included a diagnosis of degenerative joint disease, patello-femoral pathology or age under 16/over 40 (170 patients). The bony thickness of the patella, the chondral thickness and patella width were measured, as was the location of maximal patella thickness. Inter/intra observer variability was calculated and correlation analysis performed. Results We found a strong correlation between patella width and thickness (bone plus cartilage) (Pearson 0.75, P < 0.001). The mean width to thickness ratio was 1.8:1 (standard deviation 0.1, 95% confidence interval 1.78- 1.83). Without cartilage the ratio was 2.16:1 (SD 0.15, 95% CI 2.11-2.21), correlation was moderate (Pearson 0.59, P < 0.001). The average maximal patella cartilage thickness was 4.1mm (SD 1.3). Conclusion The strong correlation and narrow confidence intervals for the ratio of patella width to thickness, suggest that patella width might be used as a guide for accurate restoration of patella thickness during total knee or patello-femoral replacement. After removing osteophytes we would recommend a ratio of 1.8:1. Further work is required to establish whether there is a relationship between anterior knee pain post total knee arthroplasty and an abnormal patella width:thickness ratio.


      PubDate: 2014-07-27T22:28:39Z
       
  • Quantitative measurement lower limb mechanical alignment and coronal knee
           laxity in early flexion
    • Abstract: Publication date: Available online 23 July 2014
      Source:The Knee
      Author(s): David Russell , Angela H. Deakin , Quentin A. Fogg , Frederic Picard
      Background Non-invasive quantification of lower limb alignment using navigation technology is now possible throughout knee flexion owing to software developments. We report precision and accuracy of a noninvasive system measuring mechanical alignment of the lower limb including coronal stress testing of the knee. Methods 12 cadaveric limbs were tested with a commercial invasive navigation system against the non-invasive system. Coronal mechanical femorotibial (MFT) alignment was measured with no stress, then 15Nm varus and valgus moment. Measurements were recorded at 10° intervals from extension to 90° flexion. At each flexion interval, coefficient of repeatability (CR) tested precision within each system, and limits of agreement (LOA) tested agreement between the two systems. Limits for CR & LOA were set at 3° based on requirements for surgical planning and evaluation. Results Precision was acceptable throughout flexion in all conditions of stress using the invasive system (CR≤1.9°). Precision was acceptable using the non-invasive system from extension to 50° flexion (CR≤2.4°), beyond which precision was unacceptable (>3.4°). With no coronal stress applied, agreement remained acceptable from extension to 40° (LOA ≤2.4°), when 15Nm varus or valgus stress was applied agreement was acceptable from extension to 30° (LOA ≤2.9°). Higher angles of knee flexion had a negative impact on precision and accuracy. Conclusion & Clinical Relevance The non-invasive system provides reliable quantitative data in-vitro on coronal MFT alignment and laxity in the range relevant to assessment of collateral ligament injury, pre-operative planning of arthroplasty and flexion instability following arthroplasty. In-vivo validation should be performed.


      PubDate: 2014-07-27T22:28:39Z
       
  • Can the gracilis be used to replace the anterior cruciate ligament in the
           knee? A cadaver study
    • Abstract: Publication date: Available online 23 July 2014
      Source:The Knee
      Author(s): Etienne Cavaignac , Regis Pailhé , Jérôme Murgier , Nicolas Reina , Frederic Lauwers , Philippe Chiron
      Purpose The purpose of this study was to evaluate whether a four-strand gracilis-only graft can be used in anterior cruciate ligament (ACL) reconstruction. Study design Cadaver study Methods This study involved 16 cadaver knees. The length and diameter of the native ACL was measured in each one. The same measurements were performed on a four-strand graft of the gracilis only, the semitendinosus only and both tendons. Student's t-test was used to compare the various conditions. Results The average diameter of the G4 construct was 0.07mm greater (1%) than the native ACL (p=0.044). The average cross-sectional area of the G4 construct was 1.2mm2 greater (3.9%) than the native ACL (p=0.049). The G4 was on average 38.9mm longer than the intra-articular portion of the ACL (p<0.001). Conclusion A four-strand gracilis construct meets the anatomical specifications for use as an ACL reconstruction graft. By using the gracilis only, the morbidity associated with harvesting the gracilis and semitendinosus tendons should be reduced. Further studies must be performed to compare the biomechanical properties of this graft with other graft types and also to evaluate how this four-strand gracilis graft behaves in a clinical setting.


      PubDate: 2014-07-27T22:28:39Z
       
  • Design Changes Improve Contact Patterns and Articular Surface Damage in
           Total Knee Arthroplasty
    • Abstract: Publication date: Available online 25 July 2014
      Source:The Knee
      Author(s): Susannah L. Gilbert , Adam J. Rana , Joseph D. Lipman , Timothy M. Wright , Geoffrey H. Westrich
      Background The Optetrak® PS (Exactech, Inc., Gainesville, FL) has been a well-functioning posterior stabilized knee replacement since its introduction in 1995. In 2009, the Optetrak Logic® incorporated modifications to the anterior face of the tibial post and the corresponding anterior articulating surface of the femoral component to reduce edge loading on the polyethylene post. In this study, we provide the rationale for the design change and compare the damage on retrieved tibial components of both designs to demonstrate the effectiveness of the design modifications in decreasing post damage. Methods We integrated retrieval findings of tibial post damage with finite element analysis to redesign the anterior tibial post-femoral box articulation. We then used subsequent retrieval analysis on a 3:1 matched sample of 60 PS and 20 Logic® inserts to examine the impact of the design change on polyethylene damage. Results Polyethylene stresses were markedly reduced when rounded contact geometries were incorporated. The comparison of the new and old design using retrieval analysis demonstrated that the redesign led to reduction in surface damage and deformation on the tibial post. Conclusions This study shows the use of a design cycle by which a problem is identified through retrieval analysis, analytical tools are used to suggest design solutions, and then retrieval analysis is applied again on the new design to confirm improved performance. Clinical Relevance Anterior post damage has been markedly reduced through the introduction of design changes to the post-box geometry.


      PubDate: 2014-07-27T22:28:39Z
       
  • Case report: Total knee arthroplasty polyethylene liner disengagement
           identified by arthrography
    • Abstract: Publication date: Available online 26 July 2014
      Source:The Knee
      Author(s): David A. Bradshaw , Brian Lam , Rebekah Hoffman , Bernard Zicat
      We report a case of total knee arthroplasty polyethylene liner disengagement identified by plain film arthrography and CT arthrography.


      PubDate: 2014-07-27T22:28:39Z
       
  • Comparison of three knee braces in the treatment of medial knee
           osteoarthritis
    • Abstract: Publication date: Available online 27 July 2014
      Source:The Knee
      Author(s): Yoann Dessery , Étienne L. Belzile , Sylvie Turmel , Philippe Corbeil
      Background Conservative orthotic treatments rely on different mechanisms, such as three-point bending systems or hinges forcing external rotation of the leg and knee stabilization, to alter the biomechanics of the lower limbs and thus reduce knee loading on the affected compartment in patients with knee osteoarthritis (KOA). No previous study had compared the effects of these mechanisms on external loading and leg kinematics in patients with KOA. Methods Twenty-four patients with medial KOA (Kellgren-Lawrence grade II or III) wore three custom knee braces: a valgus brace with a three-point bending system (V3P-brace), an unloader brace with valgus and external rotation functions (VER-brace) and a functional knee brace used in ligament injuries (ACL-brace). Pain relief, comfort, kinematics and kinetics of the lower limbs during walking were compared with and without each knee brace. Results Knee pain was alleviated with all three braces (p<.01; ES=.17–.54). The VER- and ACL-braces allowed a significant reduction in peak knee adduction moment (KAM) during terminal stance from 0.313 to 0.280Nm/Bw*Ht (p<.001; ES=.28) and 0.293 to 0.268 (p<.05; ES=.22), respectively, while no significant reduction was observed with the V3P-brace (p=.52; ES=.04). Reduced knee adduction and lower ankle and knee external rotation were observed with the V3P-brace but not with the VER-brace. The ACL-brace did not modify lower limb kinematics. Conclusions No difference between the knee braces was found for pain reduction, discomfort or KAM. The VER-brace was slightly more comfortable, mainly because of its smaller size, which could ensure better compliance with treatment over the long term.


      PubDate: 2014-07-27T22:28:39Z
       
  • Asymmetries in explosive strength following anterior cruciate ligament
           reconstruction
    • Abstract: Publication date: Available online 27 July 2014
      Source:The Knee
      Author(s): Olivera M. Knezevic , Dragan M. Mirkov , Marko Kadija , Aleksandar Nedeljkovic , Slobodan Jaric
      Background Despite its apparent functional importance, there is a general lack of data regarding the time-related changes in explosive strength and the corresponding side-to-side asymmetries in individuals recovering from an ACL reconstruction (ACLR). The present study was designed to assess changes in the maximum and explosive strength of the quadriceps and hamstrings muscle in athletes recovering from an ACLR. Methods Twenty male athletes with an ACL injury completed a standard isometric testing protocol pre-ACLR, 4 and 6 months post-ACLR. In addition to the maximum strength (Fmax), the explosive strength of quadriceps and hamstrings was assessed through 4 variables derived from the slope of the force-time curves over various time intervals (RFDmax, RFD50, RFD150 and RFD250). Side-to-side asymmetries were calculated relative to post-ACLR measures of the uninvolved leg (“standard” asymmetries), and relative to pre-ACLR value of the uninvolved leg (“real” asymmetries). Results Pre-ACLR asymmetries in quadriceps RFD (average 26%) were already larger than in Fmax (14%) (p<0.05). Six months post-ACLR real asymmetries in RFD variables (33-39%) were larger than the corresponding standard asymmetries (26-28%; p<0.01). Average asymmetries in hamstrings RFD and Fmax were 10%, 25% and 15% for pre-ACLR and two post-ACLR sessions, respectively (all p>0.05). Conclusions In addition to the maximum strength, the indices of explosive strength should also be included in monitoring recovery of muscle function following an ACLR. Furthermore, pre-injury/reconstruction values should be used for the post-ACLR side-to-side comparisons, providing a more valid criterion regarding the muscle recovery and readiness for a return to sports.


      PubDate: 2014-07-27T22:28:39Z
       
  • Fixed bearing lateral unicompartmental knee arthroplasty—Short to
           midterm survivorship and knee scores for 101 prostheses
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): James R.A. Smith , James R. Robinson , Andrew J. Porteous , James R.D. Murray , Mohammad A. Hassaballa , Neil Artz , John H. Newman
      Background Isolated unicompartmental knee arthritis is less common laterally than medially. Lateral unicompartmental knee arthroplasty (UKA) constitutes only 1% of all knee arthroplasty performed. Use of medial UKA is supported by several published series showing good long-term survivorship and patient satisfaction, in large patient cohorts. Results of lateral UKA however have been mixed. We present the short and mid-term survivorship and 5-year clinical outcome of 101 lateral UKAs using a single prosthesis. Methods Over a 9year period, 100 patients who satisfied inclusion criteria underwent a lateral fixed-bearing unicompartmental arthroplasty. American Knee Society (AKSS), Oxford Knee (OKS) and modified Western Ontario McMaster Universities Arthritis Index (WOMAC) scores were completed preoperatively and at 1, 2 and 5years postoperatively. Kaplan–Meier survival analysis was used to determine the 2-year and 5-year survivorship, using revision for any cause as end point. Results Survivorship was 98.7% and 95.5% at 2 and 5years respectively. 1 knee was revised for subsidence of the tibial component and 1 knee for progression of medial compartment osteoarthritis. Of a possible 35 knees in situ at 5year follow-up, 33 knees were fully scored. Median AKSS, OKS and modified WOMAC scores were 182, 41, and 16 respectively. Conclusions The mid-term survivorship and outcome scores at 5-years suggest that lateral unicompartmental knee arthroplasty provides a valuable alternative to total joint replacement in selected patients with isolated lateral tibio-femoral arthritis at mid-term follow-up. Level II evidence.


      PubDate: 2014-06-10T16:13:21Z
       
  • Letter regarding “Does cruciate-retaining total knee arthroplasty
           enhance knee flexion in Western and East Asian patient populations' A
           meta-analysis”
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Xiaobo Xie , Lijun Lin , Qi Li



      PubDate: 2014-06-10T16:13:21Z
       
  • British Association for Surgery of the Knee
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4




      PubDate: 2014-06-10T16:13:21Z
       
  • Instructions for Authors
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4




      PubDate: 2014-06-10T16:13:21Z
       
  • Similar Early Migration when Comparing Cr and Ps In Triathlon™ TKA A
           Prospective Randomized Rsa Trial
    • Abstract: Publication date: Available online 7 June 2014
      Source:The Knee
      Author(s): Mats Molt , Sören Toksvig-Larsen
      Objectives The objective of this study was to compare the early migration of the cruciate retaining and posterior stabilising versions of the recently introduced Triathlon™ total knee system, with a view to predicting long term fixation performance. Methods Sixty patients were prospectively randomised to receive either Triathlon™ posterior stabilized cemented knee prosthesis or Triathlon™ cruciate retaining cemented knee prosthesis. Tibial component migration was measured by radiostereometric analysis postoperatively and at three months, one year and two years. Clinical outcome was measured by the American Knee Society Score and Knee Osteoarthritis and Injury Outcome Score. Results There were no differences in rotation around the three coordinal axes or in the maximal total point motion (MTPM) during the two year follow-up. The posterior stabilised prosthesis had more posterior-anterior translation at three months and one year and more caudal-cranial translation at one year and two years. There were no differences in functional outcome between the groups. Conclusion The tibial tray of the Triathlon™ cemented knee prosthesis showed similar early stability. Level of evidence Level I. Article Summary Article focus: This was a prospective randomised trial aiming to compare the single radius posterior stabilised (PS) Triathlon™ total knee arthroplasty (TKA) to the cruciate retaining Triathlon™ TKA system with regard to fixation. Strengths and limitations of this study: Strength of this study was that it is a randomized prospective trial using an objective measuring tool. The sample size of 25-30 patients was reportedly sufficient for the screening of implants using RSA [1]. Trial registration: ClinicalTrials.gov Identifier: NCT00436982.


      PubDate: 2014-06-10T16:13:21Z
       
  • Tricompartmental resurfacing arthroplasty with a follow-up of more than
           30years
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Emmanuel Thienpont , Philippe Cartier
      Background Unicompartmental and patellofemoral joint replacements are proven solutions for arthritis limited to one compartment of the knee. Bicompartmental replacement has been considered lately as an alternative for combined medial and patellofemoral arthritis. The main idea behind these resurfacing solutions is tissue preservation with conservation of bone stock and both cruciate ligaments. Tricompartmental replacement with selective resurfacing of all three compartments with different modular implants is exceptional. Methods The authors present a case with more than thirty year follow-up both clinically and radiographically. Results Excellent function and patient satisfaction are observed at 30year follow-up. Radiographs show no osteolysis or loosening of components. Conclusions Conservation of both anterior and posterior cruciate ligaments seems to protect against polyethylene wear at long-term follow-up. Level of evidence IV.


      PubDate: 2014-06-10T16:13:21Z
       
  • An original arthroscopic fixation of adult's tibial eminence fractures
           using the Tightrope® devi A report of 8 cases and review of
           literature
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Bruno Faivre , Horea Benea , Shahnaz Klouche , Florent Lespagnol , Thomas Bauer , Philippe Hardy
      Purpose The objective of this study is to asset the efficiency of the use of the Tightrope® device to treat isolated tibial spine fractures in adults. Methods All patients treated for isolated tibial spine fracture between November 2007 and February 2011 have been retrospectively included. The main judgment criteria was the post-operative knee laxity measured by Rolimeter® (Aircast) and the secondary criteria were the IKDC scores, the knee mobility, the Lachman test and the bone union. 8 patients have been included. The mean age was 34.2years (±12.5). The classification of Meyers and McKeever identified 5 types II, 2 types IIIa and 1 type IIIb. The mean follow-up period was 10months. Results The mean post-operative anterior knee laxity was 6±2.14mm for the operated side and 5.6±1.85mm for the opposite side. No significant difference was found (P =0.73). According to the IKDC classification 3 patients were normal (A), 2 were nearly normal (B), 1 was abnormal (C) and 1 was very abnormal (D). The mean IKDC subjective score was 70.71±17.56. All 8 fractures achieved union without elevation. 3 patients developed motion complications and 2 required an arthroscopic arthrolysis. No other significant complication was noted. The outcome was compared to the different series published during the last 10years. Conclusion The use of the Tightrope® device is a simple technique occurring a rigid fixation, allowing early rehabilitation with a high rate of arthrofibrosis. Level of evidence Level IV, case series.


      PubDate: 2014-06-10T16:13:21Z
       
  • Fracture of titanium nitride-coated femoral component after total knee
           arthroplasty
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Se-Wook Park , Hyungsuk Kim , Yong In
      We report a case of fracture of a titanium nitride-coated femoral component 3years after primary total knee arthroplasty (TKA). The fracture was at the medial condylar area just posterior to the medial peg of the femoral component. The backside of the broken medial condylar portion of the femoral component was devoid of cement. Debonding of the component is a possible cause of the stress fracture. To our knowledge, this is the first case report of the fracture of the femoral component manufactured from titanium alloy. Level of evidence IV


      PubDate: 2014-06-10T16:13:21Z
       
  • Patient satisfaction after posterior-stabilized total knee arthroplasty: A
           functional specific analysis
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Hui Du , Hao Tang , Jian-Ming Gu , Yi-Xin Zhou
      Background Despite the success of total knee arthroplasty (TKA) in treating end-stage knee arthritis, 11% to 19% of patients are dissatisfied with the outcome of their surgery. In this study we investigated how satisfied overall patients are with the outcome of posterior stabilized TKA and what particular functional deficits or residual symptoms cause the most dissatisfaction for patients after surgery. Methods Using patient-completed validated questionnaires, we retrospectively analyzed data for 1013 posterior-stabilized TKAs performed in 748 Chinese patients regarding the overall satisfaction with surgery and the importance ranking of each of 15 specific functions and residual symptoms. Results Our data demonstrate an overall satisfaction rate of 87.4%. Satisfaction percentages ranged from 45.0% to 89.0%. The top 6 dissatisfactory items were sitting with legs crossed (dissatisfaction rate of 55.0%), squatting (51.7%), walking fast or jogging (45.4%), knee clunking (34.5%), abnormal feeling in knee (31.2%), and climbing stairs (28.2%). The top 6 important functions or issues were pain relief, walking on flat ground, climbing stairs, ability to return to household work, decreased limping, and squatting. Conclusions Approximately 1 in 8 patients was dissatisfied with overall outcome. Patients were most dissatisfied with climbing stairs and squatting, functions that they considered most important.


      PubDate: 2014-06-10T16:13:21Z
       
  • No effect of obesity on limb and component alignment after
           computer-assisted total knee arthroplasty
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Gautam M. Shetty , Arun B. Mullaji , Sagar Bhayde , A.P. Lingaraju
      Purpose This retrospective study aimed to determine if computer navigation provides consistent accuracy for limb and component alignment during TKA irrespective of body mass index (BMI) by comparing limb and component alignment and the outlier rates in obese versus non-obese individuals undergoing computer-assisted TKA. Methods Six hundred and thirty-five computer assisted total knee arthroplasties (TKAs) performed in non-obese individuals (BMI<30kg/m2) were compared with 520 computer-assisted TKAs in obese individuals (BMI≥30kg/m2) for postoperative limb and component alignment using full length standing hip-to-ankle radiographs. Results No significant difference in postoperative limb alignment (179.7°±1.7° vs 179.6°±1.8°), coronal femoral (90.2°±1.6° vs 89.8°±1.9°) and tibial component (90.2°±1.6° vs 90.3°±1.7°) alignment and outlier rates (6.2% vs 7.5%) was found between non-obese and obese individuals. Similarly, alignment and the outlier rates were similar when non-obese individuals and a subgroup of morbidly obese individuals (BMI >40kg/m2) were compared. Conclusions Computer navigation can achieve excellent limb and component alignment irrespective of a patient's BMI. Although obesity may not be an indication per se for using computer navigation during TKA, it will help achieve consistently accurate limb and component alignment in obese patients. Level of Evidence Level II


      PubDate: 2014-06-10T16:13:21Z
       
  • Effects of increased step width on frontal plane knee biomechanics in
           healthy older adults during stair descent
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Max R. Paquette , Songning Zhang , Clare E. Milner , Jeffrey T. Fairbrother , Jeffrey A. Reinbolt
      Background Peak internal knee abduction moment is a common surrogate variable associated with medial compartment knee loading. Stair descent has been shown to yield a greater peak knee abduction moment compared to level-walking. Changes in step width (SW) may lead to changes in frontal plane lower extremity limb alignment in the frontal plane and alter peak knee abduction moment. The purpose of this study was to investigate the effects of increased SW on frontal plane knee biomechanics during stair descent in healthy older adults. Methods Twenty healthy adults were recruited for the study. A motion analysis system was used to obtain three-dimensional lower limb kinematics during testing. An instrumented 3-step staircase with two additional customized wooden steps was used to collect ground reaction forces (GRF) data during stair descent trials. Participants performed five stair descent trials at their self-selected speed using preferred, wide (26% leg length), and wider (39% leg length) SW. Results The preferred normalized SW in older adults during stair descent was 20% of leg length. Wide and wider SW during stair descent reduced both first and second peak knee adduction angles and abduction moments compared to preferred SW in healthy adults. Conclusions Increased SW reduced peak knee adduction angles and abduction moments. The reductions in knee abduction moments may have implications in reducing medial compartment knee loads during stair descent.


      PubDate: 2014-06-10T16:13:21Z
       
  • Development and validation of formulae to predict leg length following
           medial opening-wedge osteotomy of the proximal tibia with hemicallotasis
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Eiichi Nakamura , Nobukazu Okamoto , Hiroaki Nishioka , Hiroki Irie , Hiroshi Mizuta
      Background A medial open-wedge osteotomy of the proximal tibia with hemicallotasis (HCO) affects the relative coronal alignment of the femur and tibia with respect to the floor; this also potentially reflects a change in leg length. Purpose The aims of this study are to develop and verify formulae for predicting the postoperative whole leg length (WLL) in HCO. Methods We analyzed a training set of 25 HCOs in 25 patients. Formulae for predicting the postoperative leg length were developed using various factors including the length and coronal alignment of the femur and tibia, the length of the proximal or distal fragment from the tibial osteotomy site, the femoro–tibial angle, and the correction angle. The formulae were then verified using the interclass correlation coefficient in an independent consecutive set of 25 HCOs. Results Significant postoperative increases in tibial bone length and WLL were noted with no postoperative change in femoral bone length. Furthermore, the coronal alignments of femoral and tibial bone axes were significantly abducted. For the formulae for predicting postoperative WLL developed in the training set, the interclass correlation coefficients between the predicted values and the real radiographic measurements in the validation set were more than 0.90, showing great consistency. Conclusion The mathematical models established in this study seemed to predict almost completely the change in leg length after HCO. Our results suggest that these formulae may offer accurate, extremely useful information about the postoperative possibility of leg lengthening for patients planning an HCO. Level of evidence Therapeutic case series; level 4.


      PubDate: 2014-06-10T16:13:21Z
       
  • Oxidized zirconium femoral component for TKA: A follow-up note of a
           previous report at a minimum of 10years
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Massimo Innocenti , Fabrizio Matassi , Christian Carulli , Lorenzo Nistri , Roberto Civinini
      Background New bearing surfaces for total knee replacement have been described in an attempt to reduce polyethylene wear and secondary osteolysis and improve longevity of implants. Oxidized zirconium is a new material that combines the strength of a metal with the wear properties of a ceramic. However, there are no reports as to who documents the long term results. We report a 10year follow-up note of a selected series of TKAs with an oxidized zirconium femoral component. Methods We prospectively follow 98 TKAs performed in 94 patients with an oxidized zirconium femoral component. Five patients (5 knees) had died and 6 (6 knees) were lost to follow-up at a minimum of 2years (mean, 6.3years; range, 2–9years) after the operation. For the remaining 83 patients (87 knees), the minimum follow-up was 10years (mean, 11.3years; range, 10.0–12.6years). In 51 cases (58.6%), a cruciate-retaining implant with a deep-dished, more conforming PE was used, and in 36 cases (41.4%), a posterior-stabilized design was used. The patellae were resurfaced in 32 cases (36.7%) and in 55 cases (63.3%) were left unresurfaced. Results Survivorship was 97.8% at 10years postoperatively. Two knees were revised for aseptic loosening of the femoral component. No major complication was observed clinically or radiologically. Mean Knee Society score improved from 36 to 84 and functional score from 37 to 83. Conclusions Oxidized zirconium femoral component in TKA performs well over the first 10years following implantation, with excellent survival rates and good clinical and radiological outcomes. Level of evidence Level IV, therapeutic study.


      PubDate: 2014-06-10T16:13:21Z
       
  • Sealing of the intramedullar femoral canal in a TKA does not reduce
           postoperative blood loss: A randomized prospective study
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Raúl Torres-Claramunt , Pedro Hinarejos , Daniel Pérez-Prieto , Sergi Gil-González , Xavier Pelfort , Joan Leal , Lluís Puig
      Background Sealing of the femoral canal, usually with autologous bone, is a surgical procedure that is often performed during TKA surgery to decrease blood loss in the postoperative period. However, evidence as to the effectiveness of this surgical procedure is not conclusive. The objective of this study was to assess the effectiveness of this surgical action in reducing postoperative blood loss and the blood transfusion rate. Methods A randomized prospective study that included 201 TKAs divided into three groups (67 in each one) was carried out. The three groups were; A) bone graft sealing, B) cement sealing and C) unsealed canal. All groups were comparable with regard to pre and intra-operative data. The haemoglobin decrease at 2, 24 and 72h was compared to the preoperative haemoglobin value. Subsequently, blood drainage at 12 and 24h and the rate of blood transfusion were also assessed. The different complications that arose were reported. Results No statistical differences were obtained with regard to blood drainage at 12h (p=0.102) and 24h (p=0.542), the haemoglobin value decrease at 72h (p=0.95) and the number of blood transfusions (p=0.597) in the three groups studied. Conclusion There was no significant difference, whether sealing the femoral canal with a bone graft, cement or when it was left unsealed, in decreasing blood loss or blood transfusion requirements in the postoperative period. Level of evidence Therapeutic type I.


      PubDate: 2014-06-10T16:13:21Z
       
  • Comparison of peripheral nerve block with periarticular injection
           analgesia after total knee arthroplasty: A randomized, controlled study
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Kazuhide Uesugi , Naoko Kitano , Tadashi Kikuchi , Miho Sekiguchi , Shin-ichi Konno
      Background Pain after total knee arthroplasty (TKA) is usually severe. Recently, the usefulness of local periarticular injection analgesia (PAI) and peripheral nerve block (PNB) has been reported. We report a prospective blinded randomized trial of PAI versus PNB in patients undergoing primary TKA, in accordance with the CONSORT statement 2010. Methods A total of 210 patients undergoing TKA under spinal anesthesia were randomized to receive PNB group or PAI group. In the PNB group, femoral nerve block and sciatic nerve block were performed. In the PAI group, a special mixture containing ropivacaine, saline, epinephrine, morphine hydrochloride, and dexamethasone was injected into the periarticular soft tissue. Pain intensity at rest was assessed using a numerical rating scale (NRS: 0–10) after surgery. Use of a diclofenac sodium suppository (25mg) was allowed for all patients at any time after surgery, and the diclofenac sodium suppository usage was assessed. The NRS for patient satisfaction at 48hours after surgery was examined. Results The average NRS for pain at rest up to 48hours after surgery was low in both groups. Within 48hours after surgery, the diclofenac sodium suppository usage was similar in both groups. There were no significant differences in the NRS for patient satisfaction in both groups. Conclusions The analgesic effects of PAI and PNB are similar. PAI may be considered superior to PNB because it is easier to perform. Level of Evidence Therapeutic Level 1.


      PubDate: 2014-06-10T16:13:21Z
       
  • Contents List
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4




      PubDate: 2014-06-10T16:13:21Z
       
  • Editorial Board
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4




      PubDate: 2014-06-10T16:13:21Z
       
  • The management of early osteoarthritis
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Roland Jakob



      PubDate: 2014-06-10T16:13:21Z
       
  • Influence of the posterior tibial slope on the flexion gap in total knee
           arthroplasty
    • Abstract: Publication date: August 2014
      Source:The Knee, Volume 21, Issue 4
      Author(s): Ken Okazaki , Yasutaka Tashiro , Hideki Mizu-uchi , Satoshi Hamai , Toshio Doi , Yukihide Iwamoto
      Background Adjusting the joint gap length to be equal in both extension and flexion is an important issue in total knee arthroplasty (TKA). It is generally acknowledged that posterior tibial slope affects the flexion gap; however, the extent to which changes in the tibial slope angle directly affect the flexion gap remains unclear. This study aimed to clarify the influence of tibial slope changes on the flexion gap in cruciate-retaining (CR) or posterior-stabilizing (PS) TKA. Methods The flexion gap was measured using a tensor device with the femoral trial component in 20 cases each of CR- and PS-TKA. A wedge plate with a 5° inclination was placed on the tibial cut surface by switching its front–back direction to increase or decrease the tibial slope by 5°. The flexion gap after changing the tibial slope was compared to that of the neutral slope measured with a flat plate that had the same thickness as that of the wedge plate center. Results When the tibial slope decreased or increased by 5°, the flexion gap decreased or increased by 1.9±0.6mm or 1.8±0.4mm, respectively, with CR-TKA and 1.2±0.4mm or 1.1±0.3mm, respectively, with PS-TKA. Conclusions The influence of changing the tibial slope by 5° on the flexion gap was approximately 2mm with CR-TKA and 1mm with PS-TKA. Clinical relevance This information is useful when considering the effect of manipulating the tibial slope on the flexion gap when performing CR- or PS-TKA.


      PubDate: 2014-06-10T16:13:21Z
       
  • Magnetic resonance evaluation of Trufit® plugs for the treatment of
           osteochondral lesions of the knee shows the poor characteristics of the
           repair tissue
    • Abstract: Publication date: Available online 9 May 2014
      Source:The Knee
      Author(s): Pablo Eduardo Gelber , Jorge Batista , Angélica Millan-Billi , Luciano Patthauer , Silvia Vera , Mireia Gomez-Masdeu , Juan Carlos Monllau
      Background Treatment of osteochondral lesions of the knee with synthetic scaffolds seems to offer a good surgical option preventing donor site morbidity. The Trufit® plug has shown that frequently is not properly incorporated. Objective To evaluate the relationship between the MRI findings and the functional scores of patients with osteochondral lesions of the knee treated with Trufit®. Methods Patients were evaluated with the MOCART score for MRI’s assessment of the repair tissue. KOOS, SF-36 and VAS were used for clinical evaluation. Correlation between the size of the treated chondral defect and functional scores were were also analyzed. Results Fifty-seven patients with a median follow-up of 44.8months (range 24–73) were included. KOOS, SF-36 and VAS improved from a mean 58.5, 53.9 and 8.5 points to a mean 87.4, 86.6 and 1.2 at last follow-up (p<0.001). Larger lesions showed less improvement in KOOS (p=0.04) and SF-36 (p=0.029). Median Tegner’s values were restored to the preinjury situation (5, range 2–10). Mean MOCART score was 43.2±16.1. Although the cartilage layer had good integration, it showed high heterogeneity and no filling of the subchondral bone layer. Conclusions Trufit® failed to restore the normal MRI aspect of the subchondral bone and lamina in most cases. The aspect of the chondral layer in MRI was partially re-established. This unfavorable MRI aspect did not adversely influence the patient’s outcome in the short time and they restored their previous level of activity. There was an inverse linear relationship between the size of the lesion and the functional scores. Level of Evidence Therapeutic case series; level 4.


      PubDate: 2014-05-12T06:37:47Z
       
  • 5-year cost/benefit analysis of revision of failed uni-compartmental Knee
           (UKR) replacements; not “just” a primary total knee
           replacement (TKR)
    • Abstract: Publication date: Available online 6 May 2014
      Source:The Knee
      Author(s): Sam C. Jonas , Rushabh Shah , Aveek Mitra , Sunny D. Deo
      Background A number of studies suggest that one advantage of a Unicompartmental knee replacement (UKR) is ease of revision to a total (TKR). We aimed to perform a cost/benefit analysis of patients undergoing this procedure at our centre to evaluate its economic viability. Patients and Methods From our own prospective joint replacement database we identified 812 consecutive tibio-femoral UKRs performed (1994–2007) of which 23 were revised to TKR (2005–2008). These were then matched to a cohort of primary TKRs (42 patients). Data were collected regarding patient demographics, cost of surgery, clinical outcome (OKS) and follow up costs at five years. Results There was no significant difference in implant costs or in length of stay, however tourniquet time was significantly higher in the revision group (Average 93minutes (UKR) vs 75minutes (TKR) p<0.0001). At five years there was no significant difference in clinical outcome between the revision UKR and primary TKR group, mean OKS 27 and 32 respectively (p=0.20). The revision group had a greater complication and revision rate, attending significantly more follow-up appointments (Average 6 (UKR) vs 2 (TKR) p<0.0001) and consultant appointments (Average 4 (UKR) vs 0.4 (TKR) p<0.0001). This was translated to significantly higher follow up costs. Conclusion Revision of UKR to TKR is not universally a straightforward procedure comparable to a standard primary replacement. Despite cost of components not being significantly higher than primary TKR there are multiple hidden follow up costs. The clinical outcomes are however similar at 5years, indicating a favourable cost benefit.


      PubDate: 2014-05-07T06:48:24Z
       
  • Intraoperative assessment of midflexion laxity in total knee prosthesis
    • Abstract: Publication date: Available online 26 April 2014
      Source:The Knee
      Author(s): Yukihide Minoda , Shigeru Nakagawa , Ryo Sugama , Tessyu Ikawa , Takahiro Noguchi , Masashi Hirakawa , Hiroaki Nakamura
      Purpose Soft-tissue balancing of the knee is fundamental to the success of a total knee arthroplasty (TKA). In posterior-stabilized TKA, there is no stabilizer of the anterior-posterior translation in the midflexion range in which the cam-post mechanism does not engage yet. Therefore, instability in the midflexion range is suspected to occur in posterior-stabilized TKA. The purpose of this study was to measure the joint gap throughout full range of motion and to analyze the joint gap laxity in midflexion range after implantation of a mobile-bearing posterior-stabilized total knee prosthesis. Methods Joint gap kinematics in 259 knees with varus osteoarthritis were measured during TKAs using a tensor device with the same shape of a total knee prosthesis of the same design was used. After the implantation of a mobile-bearing posterior-stabilized prosthesis and the reduction of the patellofemoral joint, the joint gap was measured at 0°, 30°, 60°, 90°, 120°, and 145° of flexion. Results The center size of the joint gap was tight in extension and deep flexion and loose at midflexion ranges, especially at 30° of flexion (p<0.001). The symmetry of the joint gap was varus at 0° and 145°of flexion (p<0.001). Conclusions Our results showed the joint gap laxity in midflexion range after the implantation of a mobile-bearing posterior-stabilized prosthesis. Our new tensor device, which can attach the polyethylene insert trial, will provide the important information about the joint gap kinematics after implantation of total knee prostheses.


      PubDate: 2014-04-27T11:15:35Z
       
  • Surface extraction can provide a reference for micro-CT analysis of
           retrieved total knee implants
    • Abstract: Publication date: Available online 26 April 2014
      Source:The Knee
      Author(s): Matthew G. Teeter , Jaques S. Milner , Douglas D.R. Naudie , Steven J. MacDonald
      Background Quantitative measurements of damage and wear in orthopaedic components retrieved from patients during revision surgery can provide valuable information. However, to perform these measurements there needs to be an estimate of the original, unworn geometry of the component, often requiring multiple scans of the various sizes of components that have been retrieved. The objective of this study was to determine whether the articular and backside surfaces could be independently segmented from a micro-CT reconstruction of a tibial insert, such that a tibial insert of one thickness could be used as a reference for a tibial insert of a different thickness. Methods New tibial inserts of a single width but six different thicknesses were obtained and scanned with micro-CT. An automated method was developed to computationally segment the articular and backside surfaces of the components. Variability between intact and extracted components was determined. Results The deviations between the comparisons of the extracted surfaces (range, 0.0004 to 0.010mm) were less (p<0.001) than the baseline deviation between the intact surfaces (range, 0.0002 to 0.053mm). Conclusions An extracted surface from one insert thickness could be used to accurately represent the surface of an insert of a different thickness. This greatly enhances the feasibility of performing retrieval studies using micro-CT as a quantitative tool, by reducing the costs and time associated with acquiring, scanning, and reconstructing multiple reference tibial insert geometries. This will add greater detail to studies of retrieved implants, to better establish how implants are functioning in vivo.


      PubDate: 2014-04-27T11:15:35Z
       
 
 
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