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The Knee    [12 followers]  Follow    
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0968-0160
     Published by Elsevier Homepage  [2556 journals]   [SJR: 0.923]   [H-I: 38]
  • Ten Year Survivorship after Cemented and Uncemented Medial Uniglide®
           Unicompartmental Knee Arthroplasty
    • Abstract: Publication date: Available online 15 April 2014
      Source:The Knee
      Author(s): Klaus Schlueter-Brust
      Background : Results of knee replacement registries have shown that Unicompartmental Knee Arthroplasty (UKA) has a significantly higher revision and failure rate than current state of the art TKA. The aim of this prospective study is to evaluate the long-term outcomes and to calculate the 10year survival of knees with medial osteoarthritis treated with Uniglide® UKA. Methods : 234 Patients were assessed by an independent clinical observer using the American Knee Society Clinical Rating System, a validated outcome measure. Kaplan-Meier analysis was used to calculate the 10year survival rates using revision surgery for any cause as the end point. Results : There were no revisions due to progression of lateral osteoarthritis or polyethylene failure. There were 1 traumatic and 3 non-traumatic bearing dislocations and 2 revisions due to aseptic loosening of the tibial component. One joint was revised for traumatic ligament rupture, 1 for synovitis from bearing impingement, 1 due to femoral component mal-positioning and 1 for infection. A total of 10 cases were revised due to failures for any cause in the 61 patients withdrawn because they had died, thus giving a cumulative survival rate at 10years of 95.57 %. The knee (function) score showed an increase from 33.4 (54.7) pre-operatively to 94 (83.4) points post-operatively. The average range of motion increased from 107 to 122 degrees (p<0.01). Conclusion : Based on our findings we believe that the Uniglide® unicompartmental knee prosthesis offers a safe and effective solution for the treatment of medial compartment osteoarthritis.


      PubDate: 2014-04-17T11:25:19Z
       
  • Patient Satisfaction after Posterior-Stabilized Total Knee Arthroplasty: A
           Functional Specific Analysis
    • Abstract: Publication date: Available online 12 April 2014
      Source:The Knee
      Author(s): Du Hui , Tang Hao , Gu Jianming , Zhou Yixin
      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 were dissatisfied with overall outcome. Patients were most dissatisfied with climbing stairs and squatting, functions that they considered most important.


      PubDate: 2014-04-17T11:25:19Z
       
  • Development and validation of formulae to predict leg length following
           medial opening-wedge osteotomy of the proximal tibia with hemicallotasis
    • Abstract: Publication date: Available online 12 April 2014
      Source:The Knee
      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 while no postoperative change in femoral bone length. Furthermore, the coronal alignments of femoral and tibial bone axes had been abducted significantly. 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: 2014-04-17T11:25:19Z
       
  • Fixed Bearing Lateral Unicompartmental Knee Arthroplasty - Short to
           Midterm Survivorship and Knee Scores for 101 Prostheses
    • Abstract: Publication date: Available online 12 April 2014
      Source:The Knee
      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.


      PubDate: 2014-04-17T11:25:19Z
       
  • Fracture of titanium nitride-coated femoral component after total knee
           arthroplasty
    • Abstract: Publication date: Available online 13 April 2014
      Source:The Knee
      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-Case report


      PubDate: 2014-04-17T11:25:19Z
       
  • Tricompartmental Resurfacing Arthroplasty with a follow-up of more than
           thirty years
    • Abstract: Publication date: Available online 16 April 2014
      Source:The Knee
      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 years follow-up both clinically and radiographically. Results Excellent function and patient satisfaction are observed at 30years 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: 2014-04-17T11:25:19Z
       
  • No effect of obesity on limb and component alignment after
           computer-assisted total knee arthroplasty
    • Abstract: Publication date: Available online 16 April 2014
      Source:The Knee
      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.


      PubDate: 2014-04-17T11:25:19Z
       
  • Transepicondylar axes for femoral component rotation might produce flexion
           asymmetry during total knee arthroplasty in knees with proximal tibia vara
           
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Il Seok Park , Alvin Ong , Chang Hyun Nam , Nong Kyum Ahn , Hye Sun Ahn , Su Chan Lee , Kwang Am Jung
      Background Adequate rotation of the femoral component in total knee arthroplasty is mandatory for prevention of numerous adverse sequelae. Therefore, we investigate whether there is the distal femoral deformity in knees with tibia vara. The purpose of this study was to evaluate the reliability of the transepicondylar axis as a rotational landmark in knees with tibia vara. Methods We retrospectively reviewed and selected 101 osteoarthritic knees with proximal tibia vara and 150 osteoarthritic knees without tibia vara for inclusion in this study. The transepicondylar axis (TEA), anteroposterior (AP) axis and posterior condylar (PC) line were measured using the axial image from magnetic resonance imaging axial images. We compared the external rotation angle of the TEA relative to the PC line between groups in order to investigate the presence of distal femoral anatomical adaptation in the tibia vara group. Results The TEA in the tibia vara group had 6.1º of external rotation relative to the PC line, which was not significantly different from the 6.0º of external rotation in the non-tibia vara group. The line perpendicular to the AP axis in the tibia vara group had 6.1º of external rotation relative to the PC line, which was not significantly different from the 5.4º of external rotation in the non-tibia vara group. Distal femoral geometry was unaffected by the tibia vara deformity. Conclusions The use of transepicondylar axes in determining femoral rotation may produce flexion asymmetry in knees with tibia vara. Level of evidence Level III


      PubDate: 2014-04-07T16:20:09Z
       
  • Improvement of femoral component size prediction using a C-arm intensifier
           guide and our established algorithm in unicompartmental knee arthroplasty:
           A report from a Chinese population
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Yihui Tu , Huaming Xue , Minwei Cai , Tong Ma , Xiaodong Liu , Zhidao Xia
      Background Unicompartmental knee arthroplasty (UKA) is becoming more widely used with the recent increase in popularity of the use of minimally invasive techniques. However, it is difficult to judge about the femoral component size in UKA using preoperative templating digitally or otherwise. Even when using navigation it is impossible to control the femoral component size. The aim of this study is to develop a better pre- or intra-operative measure that will predict femoral component size. Methods Ninety-two UKA cases were studied from June 2007 to December 2011 with a mean 26-month follow-up. We developed an intra-operative C-arm intensifier guide (CAIG) method for determining femoral size instead of pre-operative templating. The accuracy of prediction of both methods was compared from a review of post-operative radiographs. In addition, we summarized all cases and developed a Chinese algorithm to determine the femoral component size pre-operatively. Results There was a significant difference between templating (59%) and CAIG (92%) method (P=0.0001). In the Chinese algorithm, height based on gender and tibial size both have greater accuracy of prediction (88% and 70.7%) than the Oxford algorithm (51.1% and 59.8%). Component size distribution and optimal tibial/femoral pairing differed from those in the Oxford report. Conclusions We conclude that the Chinese algorithm can greatly improve the accuracy of prediction of femoral component size. In addition, CAIG-assisted implantation of a UKR is a reliable intra-operative tool and can aid size selection of the femoral component. Level of Evidence Level III.


      PubDate: 2014-04-07T16:20:09Z
       
  • Unicompartmental knee arthroplasties: Robot vs. patient specific
           instrumentation
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Zahra Jaffry , Milad Masjedi , Susannah Clarke , Simon Harris , Monil Karia , Barry Andrews , Justin Cobb
      Background The technical reliability demonstrated by semi active robots in implant placement could render unicompartmental knee arthroplasties (UKAs) more favourable than they are currently. The relatively untested method using patient specific instrumentation (PSI), however, has the potential to match the accuracy produced by robots but without the barriers that have prevented them from being used more widely in clinical practice, namely operative time. Therefore this study took a step towards comparing the accuracy and time taken between the two technologies. Methods Thirty-six UKAs were carried out on identical knee models, 12 with the Sculptor, 12 with PSI and 12 conventionally under timed conditions. Implant placement in these knees was then judged against that in a pre-operative plan. Results Tibial implant orientations and femoral implant positions and orientations were significantly more accurate in the PSI group with mean errors of 6°, 2mm and 4° respectively, than the conventional group which had means of 9°, 4mm and 10°. There was no significant difference between the robot and PSI generally except in tibial implant orientation (mean robotic error 3°) and tibial implant position did not vary significantly across all three groups. It was also found that use of PSI and conventional methods took half the time taken by the robot (p <0.001). Conclusions With further development, PSI can match and possibly surpass the accuracy of the robot, as it does with the conventional method, and achieve planned surgery in less time. Clinical relevance This work sets the foundation for clinical trials involving PSI.


      PubDate: 2014-04-07T16:20:09Z
       
  • Functional outcomes following total knee arthroplasty: A randomised trial
           comparing computer-assisted surgery with conventional techniques
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): William G. Blakeney , Riaz J.K. Khan , Jennifer L. Palmer
      Background A number of trials have shown improved radiological alignment following total knee arthroplasty using computer-assisted surgery (CAS) compared with conventional surgery. Few studies, however, have looked at functional outcomes. Methods We prospectively studied a cohort of 107 patients that underwent TKA by a single surgeon. Patients were randomised into 3 groups: computer-assisted surgery for both the femur and the tibia, intramedullary guides for both the femur and the tibia, and an intramedullary guide for the femur and an extramedullary guide for the tibia. Patients were followed-up post-operatively with the Short Form Health Survey (SF-12) and Oxford Knee Score (OKS) questionnaires. Results At a median follow-up of 46months (range 30-69months), there was a trend towards higher OKS results in the CAS group, with a mean score of 40.6 in the CAS group compared to 37.6 in the extramedullary group and 36.8 in the intramedullary group. The difference seen in the OKS between CAS and the conventional groups had a significant unadjusted p-value (0.024), and approached significance when adjusted for age and sex (0.054). There was a significant improvement in the OKS when the mechanical axis was within ±3° of neutral, versus those outside this range (median of 41.0 compared to 38.3, p=0.045). Discussion This study shows that clinically significant differences are being seen in functional scores of patients treated with CAS versus conventional guides, at medium-term follow up. Our findings reinforce the tenet that a coronal mechanical axis of within 3° of neutral equates to significantly better functional outcomes.


      PubDate: 2014-04-07T16:20:09Z
       
  • Polyethylene particles in joint fluid and osteolysis in revision total
           knee arthroplasty
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Ignasi Piñol , Alberto Torres , Gabriel Gil , Eva Prats , Lluis Puig-Verdier , Pedro Hinarejos
      Background One of the most frequent reasons for total knee arthroplasty late failure is osteolysis. It has been related to foreign body reaction to polyethylene particles. The aim of this study is to analyse the number, size and morphology of polyethylene particles in synovial fluid in total knee arthroplasty revision and correlate them to the pathology and the degree of osteolysis. Methods Synovial fluid was obtained in 12 patients before the revision total knee arthroplasty. Polyethylene particles were isolated and analysed through scanning electron microscopy. Samples of synovial tissue were analysed with optical microscopy while considering the parameters of particles and histiocytic infiltration. Osteolysis was analysed with plain radiography and the macroscopic aspect during surgery. Results The statistical analysis showed a significant correlation between a high concentration of polyethylene particles in synovial fluid and a high degree of osteolysis. The concentration of particles in synovial fluid also showed a significant correlation with a high degree of particles and histiocytes in the histological analysis. There was a relationship between the size of particles and the degree of osteolysis. No relationship was found between the shape of the particles and the histological findings or the degree of osteolysis. Conclusions In an “in vivo” TKA scenario, the presence of a high concentration of polyethylene particles in the synovial fluid seems to be the cause of a highly active foreign body histological reaction, with an increased number of histiocytes, which seems to be the cause of a significant degree of osteolysis around the implant.


      PubDate: 2014-04-07T16:20:09Z
       
  • The influence of leg length difference on clinical outcome after revision
           TKA
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): S. Mufty , H. Vandenneucker , J. Bellemans
      Background The purpose of this paper was to document the incidence of leg length changes after revision total knee arthroplasty (TKA) and its effect on clinical outcome. Methods Leg length difference (LLD) was prospectively measured in 85 patients using digital standing full leg radiography before and after revision TKA. Additionally the patient's subjective perception of LLD was assessed postoperatively. Linear regression models were used to study the correlation between each of these parameters and the clinical outcome after 1year. Clinical outcome was evaluated by means of the Knee Society Score (KSS). Results Revision TKA resulted on average in an increased leg length of 5.3mm. Sixty-five legs (76%) were lengthened with the procedure, 17 (20%) were shortened and three (4%) remained of identical length. Increased leg length after revision was positively correlated with clinical outcome at 3months (Spearman r=0.22, p=0.044) and 1year (Spearman r=0.26, p=0.027). The evidence for this correlation remained after correction for age, gender and diagnosis (p=0.012). The most important contributors to improved clinical outcome scores were improved pain score (Spearman r=0.19, p=0.09) and increased stability (Spearman r=0.13, p=0.24), rather than range of motion (Spearman r=−0.02, p=0.85). Conclusions The results from our work indicate that revision TKA tends to lengthen the leg by approximately 5mm. Contrary to what might be expected, leg lengthening after revision TKA is correlated with improved clinical outcome. Level of evidence Level 2b.


      PubDate: 2014-04-07T16:20:09Z
       
  • Clinical and radiological results of femoral head structural allograft for
           severe bone defects in revision TKA — A minimum 8-year follow-up
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Churl Hong Chun , Jeong Woo Kim , Sung Hun Kim , Bong Gyu Kim , Keun Churl Chun , Kwang Mee Kim
      Background Proper treatment of bone loss is essential for the long term durability of revision TKA. However, the method of choice in managing large bone defects is still under debate. We therefore assessed the mid to long term clinical and radiographic results of revision TKA using a fresh frozen femoral head allograft and a standard condylar implant or varus–valgus constrained prosthesis with a diaphyseal-engaging stem. Methods We retrospectively reviewed the records of 27 patients who had undergone revision TKA between August 1997 and March 2003 using a fresh frozen femoral head allograft and a standard condylar implant or varus–valgus constrained prosthesis with a diaphyseal-engaging stem. The median follow-up period was 107months (range, 96–157months). Results Clinical evaluation revealed that the mean range of motion had increased from 71° to 113° and the mean Hospital for Special Surgery knee score had improved from 46 to 83 points. The overall tibio-femoral angle improved from varus 7.3° to valgus 6.l°. In 26 out of 27 knees, union was demonstrated at an average of seven months postoperatively, and there were no cases of collapse, disease transmission or stress fractures. In one knee, an infection recurred. Conclusions Our results demonstrate that femoral head allografts in treatment of severe bone defects are reliable and durable. If possible, less constrained prostheses with diaphyseal-engaging stems should be chosen for increased durability. Level of evidence Level IV, therapeutic study. See Guidelines for
      Authors for a complete description of levels of evidence.


      PubDate: 2014-04-07T16:20:09Z
       
  • Influence of low back pain on total knee arthroplasty outcome
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): J.K. Boyle , I.C. Anthony , B.G. Jones , E.F. Wheelwright , M.J.G. Blyth
      Background Preoperative pain and functional status are strong determinants of postsurgical success in total knee arthroplasty. Patients suffering chronic pain from other coexistent musculoskeletal problems may respond differently postoperatively, with potentially poorer outcomes after surgery. The aim of the study was to determine the influence of low back pain on the outcome of total knee replacement surgery. Methods All patients completed Oxford Knee Scores (OKS), American Knee Society Scores (AKSS) and SF-12 (both physical and mental components). Patients were divided into those with (n=40) and without a documented history of low back pain (n=305). Results OKS, AKSS and SF-12 physical scores were significantly worse for patients with low back pain at 24months following surgery. The mental component of the SF-12 measure demonstrated a significant improvement in median mental health post-operatively for patients with no current history of low back pain. In contrast the group with low back pain showed no improvement in mental health scores post-operatively. Conclusion This study demonstrates that symptomatic low back pain influences functional outcome after total knee arthroplasty surgery and that patients with low back pain show limited or no improvement in mental health post-operatively. Level of evidence II.


      PubDate: 2014-04-07T16:20:09Z
       
  • A comparison of alignment using patient specific guides, computer
           navigation and conventional instrumentation in total knee arthroplasty
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Samuel J. MacDessi , Bob Jang , Ian A. Harris , Emma Wheatley , Carl Bryant , Darren B. Chen
      Background Patient specific guides (PSG) have been introduced as a tool in total knee arthroplasty (TKA) in an attempt to improve limb alignment and reduce operative time compared to other established surgical techniques. The purpose of this study was to compare the post-operative radiographic alignment and operative time in patients who underwent TKA surgery with PSG, conventional instrumentation or computer-assisted navigation surgery using fully cemented components. Methods A cohort of 260 patients who underwent TKA surgery using PSG (PSG group, n =115) was compared to patients who underwent TKA using either conventional instrumentation (CON group, n =92) or computer-assisted navigation (CAS group, n =53). Post-operative CT imaging using the Perth CT protocol was used to compare alignment between the three groups. Results In the PSG and CAS groups, the post-operative hip–knee angle (HKA) was within 3° of neutral alignment in 91.3% and 90.7% of patients, respectively. This compared to 80.4% of patients in the CON group (p =0.02). There were no significant differences with respect to alignment when comparing individual component positioning between the PSG and CAS groups apart from tibial slope (Table 3). Total operative time was found to be significantly reduced in the PSG group (80.2min) compared to both the CON group (86min, p =0.002) and the CAS group (110.2min, p <0.0001). Conclusions The use of PSG resulted in similar alignment accuracy to CAS and superior alignment to CON with significantly shorter operative times.


      PubDate: 2014-04-07T16:20:09Z
       
  • The effect of tourniquet use on fixation quality in cemented total knee
           arthroplasty a prospective randomized clinical controlled RSA trial
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Mats Molt , Andreas Harsten , Sören Toksvig-Larsen
      Background A concern that arises with any change in technique is whether it affects the long-term implant stability. The objective of this study was to evaluate the early migration, measured by radiostereometric analysis (RSA), and the functional outcome of the Triathlon™ cemented knee prosthesis, operated on with or without a tourniquet. During the last decades RSA has emerged as a way to assess prosthetic fixation and long time prognosis. The method has been used extensively in both hip and knee arthroplasty. Method This was a single centre prospective study including 60 patients randomized into two groups operated on either with or without tourniquet. RSA investigation was done within 2–3days postoperatively after full weight bearing, and then at 3months, 1year and 2years postoperatively. Results There were no differences between the groups regarding the translation along or rotation around the three coordinal axes, or in maximum total point motion (MTPM). At 2years the mean MTPM (SD) was 0.71mm (0.64) for the tourniquet-group and 0.53mm (0.21) for the non-tourniquet-group. Conclusions The tibial tray of the Triathlon™ cemented knee prosthesis showed similar early stability whether operated on with or without tourniquet. Level of evidence Level I. Article summary Article focus: A safety study for total knee replacement operated on with or without perioperative tourniquet regarding the prosthetic fixation. Strengths and limitations: Strength of this study is that it is a randomized prospective trial using an objective measuring tool. The sample size of 25–30 patients is reportedly sufficient for the screening of implants using RSA (1–3). Trial registration: Clinical trials NCT01604382, Ethics Committee approval D-nr: 144/20085.


      PubDate: 2014-04-07T16:20:09Z
       
  • A method for assessing joint line shift post knee arthroplasty considering
           the preoperative joint space
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Shahram Amiri , Bassam A. Masri , Carolyn Anglin , David R. Wilson
      Background Accurate comparison of outcomes regarding various surgical options in knee arthroplasty can benefit from an improved method for joint line analysis that takes into account the preoperative joint space. Methods This article describes a new preoperative-based registration method that measures changes in the joint line by overlaying the 3D models of the bones with implants using preoperative CT along with preoperative and postoperative biplanar radiography. The method was tested on six cadaveric specimens for measuring alteration to the medial and lateral joint lines in extension and flexion. Results The joint line shift, when measured using the new method, was in the range of −0.2 to 1.3mm on average (SD=1.3 to 3.8mm, for medial and lateral, in flexion and extension positions). This was significantly different (p≤0.01) from the results of a previous postoperative-based registration method which did not account for the cartilage thickness in calculating alterations of the joint line (mean=3.9 to 6.8mm, SD=1.2 to 4.3mm). Conclusion These results further highlight the importance of considering the preoperative joint space in analyzing the joint line, and demonstrate the utility of the newly introduced method for accurate assessment of changes in the joint line after arthroplasty. Clinical relevance The introduced method provides accurate means for investigating joint line alterations in relation to different surgical techniques and the subsequent biomechanical effects after knee arthroplasty


      PubDate: 2014-04-07T16:20:09Z
       
  • Gait analysis of fixed bearing and mobile bearing total knee prostheses
           during walking: Do mobile bearings offer functional advantages'
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Samuel G. Urwin , Deiary F. Kader , Nick Caplan , Alan St Clair Gibson , Su Stewart
      Background Limited previous findings have detailed biomechanical advantages following implantation with mobile bearing (MB) prostheses after total knee replacement (TKR) surgery during walking. The aim of this study was to compare three dimensional spatiotemporal, kinematic, and kinetic parameters during walking to examine whether MBs offer functional advantages over fixed bearing (FB) designs. Methods Sixteen patients undergoing primary unilateral TKR surgery were randomised to receive either a FB (n =8) or MB (n =8) total knee prosthesis. Eight age and gender matched controls underwent the same protocol on one occasion. A 12 camera Vicon system integrated with four force plates was used. Patients were tested pre-surgery and nine months post-surgery. Results No significant differences between FB and MB groups were found at any time point in the spatiotemporal parameters. The MB group was found to have a significantly reduced frontal plane knee range of motion (ROM) at pre-surgery than the FB group (FB=14.92±4.02°; MB=8.87±4.82°), with the difference not observed post-surgery. No further significant kinematic or kinetic differences were observed between FB and MB groups. Fixed bearing and MB groups both displayed spatiotemporal, kinematic, and kinetic differences when compared to controls. Fixed bearing and MB groups differed from controls in six and five parameters at nine months post-surgery, respectively. Conclusions No functional advantages were found in knees implanted with MB prostheses during walking, with both groups indicative of similar differences when compared to normal knee biomechanics following prosthesis implantation. Level of evidence Level II.


      PubDate: 2014-04-07T16:20:09Z
       
  • Effects of increased step width on frontal plane knee biomechanics in
           healthy older adults during stair descent
    • Abstract: Publication date: Available online 3 April 2014
      Source:The Knee
      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 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: 2014-04-07T16:20:09Z
       
  • Contents List
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2




      PubDate: 2014-04-07T16:20:09Z
       
  • Editorial Board
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2




      PubDate: 2014-04-07T16:20:09Z
       
  • Arthroscopy in the management of knee osteoarthritis
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Simon Donell , Emeritus Editor



      PubDate: 2014-04-07T16:20:09Z
       
  • Application of a novel design method for knee replacements to achieve
           normal mechanics
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Peter S. Walker
      Purpose The purpose of this study was to utilize a novel method for the design of total knee replacements for use in the absence of the cruciate ligaments, with the design criteria of reproducing the medial stability and lateral mobility characteristics of the normal anatomic knee. Scope The starting point was a femoral component with surfaces approximating anatomic. This surface was moved into multiple positions describing a neutral path of motion and laxity about the neutral path. The distal part of the femoral composite was then used to define the tibial surface. By varying the femoral design, different tibial surfaces were produced. The reference design featured a dished medial tibial surface and a shallow lateral tibial surface, but this provided limited motion guidance. To provide further guidance, two types of design were generated, one using intercondylar guide surfaces, the other providing guidance from the condylar surfaces themselves. Conclusions The design method was capable of generating a range of total knee surfaces which could potentially return the arthritic knee to more normal function.


      PubDate: 2014-04-07T16:20:09Z
       
  • Vascular Anatomy of the Patella: Implications for Total Knee Arthroplasty
           Surgical Approaches
    • Abstract: Publication date: Available online 2 April 2014
      Source:The Knee
      Author(s): Lionel E. Lazaro , Michael B. Cross , Dean G. Lorich
      Background Iatrogenic disruption of the patellar vascular supply has been identified as a possible contributing factor to the commonly reported patellofemoral complications following total knee arthroplasty (TKA). We performed an anatomic cadaveric study evaluating the extra-osseous vascular anatomy of the patella, and correlated our findings to routine TKA surgical dissection to determine how to better preserve patellar vascularity. Methods and Materials In twenty-one cadaveric knees arterial cannulas were placed proximally and distally to the patella. A polyurethane compound was then injected producing a visible arterial network. Specimens underwent gross dissection. Results In all 21 specimens, the supreme genicular (SGA), medial/lateral superior genicular (MSGA/LSGA), medial/lateral inferior genicular and anterior tibial recurrent arteries communicate forming a peripatellar anastomotic ring supplying the intraosseous patellar system. Both, the SGA (24%) and MSGA (76%) demonstrated dual medial ring contribution. Relating the arterial location to common TKA exposures suggested severe compromise of patellar vascularity. Conclusion The medial sided vessels seem to contribute more significantly to the peripatellar anastomotic ring when compared to the lateral sided vessels. Careful soft tissue management has the potential to preserve key vascular structures that could maintain the intraosseous vascular supply to the patella. Understanding the anatomic locations of major arterial systems around the knee joint can potentially help during hemostasis, and can minimize blood lost during TKA. Clinical Relevance Recognition of major arterial systems around the knee joint has the potential to minimize iatrogenic disruption of the vascular supply and the complications that can follow (patella devascularization and blood lost).


      PubDate: 2014-04-07T16:20:09Z
       
  • Satisfactory results at 8years mean follow-up after ADVANCE®
           medial-pivot total knee arthroplasty
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Nobuaki Chinzei , Kazunari Ishida , Nobuhiro Tsumura , Tomoyuki Matsumoto , Atsushi Kitagawa , Tetsuhiro Iguchi , Kotaro Nishida , Toshihiro Akisue , Ryosuke Kuroda , Masahiro Kurosaka
      Background Although good overall results have been reported with TKA, certain problems and limitations remain, primarily due to postoperative differences in joint kinematics, when compared with the normal knee. ADVANCE® Medial-Pivot TKA involves replicating the medial pivoting behavior observed in normal knees. Here, we aimed to investigate the clinical and radiological results and complications of TKA using this implant, at mid-term follow-up. Methods From January 2001 to March 2012, we retrospectively selected 76 patients (85 knees; mean age at operation, 70.2±8.1years; range, 51–88years) with a mean follow-up period of 93.1±14.3months (range, 72–132months). Indications for TKA included primary degenerative osteoarthritis (60 knees), rheumatoid arthritis (22 knees), osteonecrosis (two knees), and osteoarthritis following high tibial osteotomy (one knee). The clinical and radiographic results were evaluated. Results Kaplan–Meier survivorship analysis indicated a success rate of 98.3% (95% confidence interval, 96.6–99.9%). Comparison of pre- and postoperative knee extension angles and ranges of motion showed significant improvement postoperatively, in both the Knee Society Scores (KSS) and Knee Society Functional Scores (KSFS) (p<0.05). In one case, radiographic assessment indicated implant loosening due to infection; however, despite this complication, significant improvement of postoperative varus or valgus deformity angles were noted in all cases (p<0.05). Conclusion Patients undergoing ADVANCE® Medial-Pivot TKA achieved excellent clinical and radiographic results without any implant-related failures at mid-term follow-up. Level of eviden Level IV


      PubDate: 2014-04-07T16:20:09Z
       
  • Preliminary investigation of rate of torque development deficits following
           total knee arthroplasty
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Joshua D. Winters , Cory L. Christiansen , Jennifer E. Stevens-Lapsley
      Background To assess changes in maximal strength and rate of torque development (RTD) following TKA, and examine the relationships between these measures and physical function. Methods Thirty-five TKA patients and 23 controls completed isometric knee extensor torque testing preoperatively, 1, and 6months after surgery. Maximal strength was calculated as the peak torque during a maximal voluntary isometric contraction (MVIC) of the knee extensor muscles, peak RTD (RTDpeak) was calculated as the maximum value from the 1st derivative of the isometric knee extension torque data, RTD25% and RTD 50% were calculated as the change in force over the change in time from force onset to 25% and 50% MVIC. Physical function was measured using a timed-up-and-go (TUG) and stair climbing test (SCT). Results RTD was significantly lower in the TKA group, at all-time points, compared to the Controls. MVIC and RTD significantly decreased 1-month following surgery (p =0.000 for all measures). RTDpeak measures added to linear regressions with strength improved the prediction of TUG scores (p =0.006) and the SCT scores (p =0.015) 1-month post-surgery. Adding RTD50% to the regression model, following MVIC, improved predicting both TUG (p =0.033) and SCT (p =0.024). At 6-months, the addition of RTD25% to the regression model, following MVIC, improved the prediction of TUG (p =0.037) and SCT (p =0.036). Conclusion Following TKA, physical function is influenced by both the maximal strength and the rate of torque development of the knee extensors, and the prediction of function is improved with the addition of RTD compared to that of maximal strength alone.


      PubDate: 2014-04-07T16:20:09Z
       
  • Mobile bearing or fixed bearing' A meta-analysis of outcomes comparing
           mobile bearing and fixed bearing bilateral total knee replacements
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Zhan-dong Bo , Liang Liao , Jin-min Zhao , Qing-jun Wei , Xiao-fei Ding , Biao Yang
      Background To compare outcomes between mobile-bearing (MB) and fixed-bearing (FB) in bilateral total knee replacements. Methods The MEDLINE, EMBASE and Cochrane Library databases were searched. Randomized controlled trials of bilateral total knee arthroplasty with one of each design implanted were identified. Weighted mean differences (WMDs) and pooled risk ratios (RRs) were calculated using fixed- or random-effects models. Results Twelve studies were identified with a total of 807 patients and 1614 knees. All RCTs were of high quality with a low risk of bias. No statistical difference was found between MB and FB at 2- to 5-year follow-up in terms of America Knee Society score (WMD: −1.29, 95% CI: −5.65 to 3.06), pain score (WMD: −3.26, 95% CI: −10.45 to 3.93), range of motion (WMD: −4.16, 95% CI: −9.97 to 1.66), reoperation (RR: 1.00, 95% CI: 0.28 to 3.60), and radiolucent lines (RR: 1.51, 95% CI: 0.70 to 3.24). The results were similar at 1-, 5- to 8-, or >8-year follow-up. Patient's satisfaction (RR: 0.85, 95% CI: 0.54 to 1.34), and complication (≤2-year, RR: 0.55, 95% CI: 0.29 to 1.04; >2-year, RR: 1.0, 95% CI=0.73 to 1.38) also showed no difference between two groups. Conclusions Based on this meta-analysis we are unable to detect the superiority of MB as compared to FB. More randomized trials with a larger sample size and longer follow-up are needed to evaluate these two kinds of prosthesis. Level of evidence Therapeutic Level II.


      PubDate: 2014-04-07T16:20:09Z
       
  • Comparison the effect of lateral wedge insole and acupuncture in medial
           compartment knee osteoarthritis: A randomized controlled trial
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Alireza Ashraf , Fariba Zarei , Mohammad Javad Hadianfard , Behrooz Kazemi , Soleiman Mohammadi , Mahshid Naseri , Ali Nasseri , Mehdi Khodadadi , Mehrab Sayadi
      Background There is lack of well-designed trials evaluating structural benefits of non-pharmacologic therapies in knee osteoarthritis (OA). In this parallel-group randomized controlled trial, we aim to compare the possible advantages of lateral wedge insole and acupuncture in patients with medial knee OA. Method Patients with grade two or three of medial knee OA were randomly allocated to group one who received an in shoe lateral wedge and group two who underwent acupuncture. We assessed patients' pain, function and knee joint cartilage thickness before and after intervention. Paired t-test and independent samples t-test were used for in group and between group analyses. (Level of eviden 2.) Results Twenty patients in each group were recruited in the study. Pain significantly decreased after therapy in both groups one and two (paired t test, P<0.001, 95% CI: 1.62–3.25 and 1.58–3.20 respectively). Function improved in each group (paired t test, P=0.001, 95% CI of 0.94–2.38 in group one and 0.97–2.43 in group two). A non-clinically statistically significant difference regarding the femoral and tibial cartilage thickness was obtained in both groups one (P=0.005, CI: −0.43–0.82 and P=0.037, CI: −0.44–0.80 respectively) and two (P=0.025, CI: −0.45–0.79 and P=0.035, CI: −0.29–0.96 respectively). Between groups analysis showed no significant difference regarding abovementioned measures. Conclusion Both lateral wedge insole and acupuncture can be effective in the treatment of medial knee osteoarthritis without any superiority of one over the other. Iranian Registry of Clinical Trials: IRCT201201108235N1. URL: http://irct.ir/searchen.php


      PubDate: 2014-04-07T16:20:09Z
       
  • Cartilage repair procedures associated with high tibial osteotomy in varus
           knees: Clinical results at 11years' follow-up
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): A. Ferruzzi , R. Buda , M. Cavallo , A. Timoncini , S. Natali , S. Giannini
      Background and aim In this study, the authors retrospectively compared the clinical outcome of middle-aged active patients affected by a varus knee with medial unicompartmental osteoarthritis: the treatment was isolated high tibial osteotomy (HTO) for one group or HTO associated with a cartilage repair procedure, that was autologous chondrocyte implantation (ACI) for one group (HTO+ACI) and microfracture (MFX) for the other group (HTO+MFX). The purpose of this study was to analyse the clinical outcomes at long-term follow-up. The hypothesis was that a cartilage repair procedure may add some benefit to isolated axial correction. Methods 56 patients affected by medial osteoarthcritis in a varus knee were retrospectively investigated: 20 patients were treated by HTO, 18 by HTO+ACI and 18 by HTO+MFX. All patients underwent clinical assessment following HSS and WOMAC rating scores and a radiographic study was performed preoperatively and at follow-up. The statistical analysis confirmed that the three groups of patients were homogeneous regarding clinical, radiographical and anatomopathological patterns; differences have been reported in body mass index (BMI). Results At final follow-up, improvements in clinical and radiographical results were obtained in all patients. HTO and HTO+ACI series showed significantly higher scores compared to the HTO+MFX series. Conclusions At more than 11years of follow-up, isolated HTO and HTO+ACI treatments showed satisfactory results similar to those reported in the literature with no evidence of superiority of the addition of ACI to isolated HTO. MFX associated with HTO provided the worst results in the series.


      PubDate: 2014-04-07T16:20:09Z
       
  • The weight-bearing scanogram technique provides better coronal limb
           alignment than the navigation technique in open high tibial osteotomy
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Dae-Hee Lee , Seoung-Bum Han , Kwang-Jun Oh , Jun Seop Lee , Jae-Ho Kwon , Jong-In Kim , Smarajit Patnaik , Gautam M. Shetty , Kyung-Wook Nha
      Background Successful outcomes following high tibial osteotomy (HTO) require precise realignment of the mechanical axis of the lower extremity. The present study investigated whether the weight-bearing limb scanogram (WBS) technique provided a more accurate mechanical axis realignment than the navigation technique in open high tibial osteotomy (OHTO). Methods This prospective study involved 80 knees (78 patients) undergoing OHTO. The WBS technique was used in 40 knees and the navigation technique in 40 knees. Each technique was performed by a different surgeon in a different hospital. Postoperative coronal limb alignment was assessed using the weight-bearing line (WBL) ratio on full-length standing hip-to-ankle radiographs. Results We found that the mean postoperative WBL ratio was greater in the WBS compared to the navigation group (p =0.001), and hence the ratio for the WBS group was closer to the ratio target of 62%. There was a greater proportion of WBL ratio outliers in the navigation group than the WBS group (25% vs. 10%, p =0.034). Conclusion We conclude that the WBS technique was more accurate than the navigation technique for restoration of coronal leg alignment in OHTO. Level of Evidence Level II.


      PubDate: 2014-04-07T16:20:09Z
       
  • A preference-based single-item measure of quality of life following medial
           opening wedge high tibial osteotomy: Large improvements similar to
           arthroplasty
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Iain R. McNamara , Trevor B. Birmingham , Jacquelyn D. Marsh , Bert M. Chesworth , Dianne M. Bryant , J. Robert Giffin
      Background Improvements in generic and disease specific scores have been reported with medial opening wedge high tibial osteotomy (MOW HTO). However, meaningful comparisons between competing surgical interventions have been hampered by the lack of a preference based single index of health related quality of life (HRQoL). The primary aim of this study was to derive and report a single index measure of HRQoL for patients undergoing MOW HTO, preoperatively and at 12 and 24 postoperatively. Secondary aims were to evaluate changes in various additional measures of quality of life at these time points. Methods The impact of MOW HTO was evaluated using generic and disease specific instruments. One hundred thirty eight patients completed the Medical Outcomes Study short form health survey (SF-12) and Knee Osteoarthritis Outcomes Score (KOOS) before, 12 and 24months after surgery. A preference-based single index measure of HRQoL was calculated and changes were evaluated. Results The mean change in the HRQoL suggested large, clinically significant improvements from 0.69 preoperatively to 0.82 (p<0.001) and 0.8 at 12 and 24months postoperatively respectively. All dimensions of the SF-12, except role mental health, and all dimensions of the KOOS also demonstrated statistically significant improvements between pre and postoperative measurements. Conclusions The preoperative HRQoL of young patients with mechanical varus alignment and medial compartment knee osteoarthritis is similar to older patients with knee osteoarthritis. Medial opening wedge high tibial osteomoty results in significant improvements in HRQoL, the magnitude of which is comparable to other surgical interventions for knee osteoarthristis.


      PubDate: 2014-04-07T16:20:09Z
       
  • Is reconstruction the best management strategy for anterior cruciate
           ligament rupture' A systematic review and meta-analysis comparing
           anterior cruciate ligament reconstruction versus non-operative treatment
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): T.O. Smith , K. Postle , F. Penny , I. McNamara , C.J.V. Mann
      Aims The purpose of this study was to determine the optimal clinical and cost-effective strategy for managing people following ACL rupture. Methods A systematic review of the published (AMED, CINAHL, MEDLINE, EMBASE, PubMed, psycINFO and the Cochrane Library) and unpublished literature (OpenGrey, the WHO International Clinical Trials Registry Platform, Current Controlled Trials and the UK National Research Register Archive) was conducted on April 2013. All randomised and non-randomised controlled trials evaluating clinical or health economic outcomes of isolated ligament reconstruction versus non-surgical management following ACL rupture were included. Methodological quality was assessed using the PEDro appraisal tool. When appropriate, meta-analysis was conducted to pool data. Results From a total of 943 citations, sixteen studies met the eligibility criteria. These included 1397 participants, 825 who received ACL reconstruction versus 592 who were managed non-surgically. The methodological quality of the literature was poor. The findings indicated that whilst reconstructed ACL offers significantly greater objective tibiofemoral stability (p <0.001), there appears limited evidence to suggest a superiority between reconstruction versus non-surgical management in functional outcomes. There was a small difference between the management strategies in respect to the development of osteoarthritis during the initial 20years following index management strategy (Odds Ratio 1.56; p =0.05). Conclusions The current literature is insufficient to base clinical decision-making with respect to treatment opinions for people following ACL rupture. Whilst based on a poor evidence, the current evidence would indicate that people following ACL rupture should receive non-operative interventions before surgical intervention is considered.


      PubDate: 2014-04-07T16:20:09Z
       
  • Biomechanics of single-tunnel double-bundle anterior cruciate ligament
           
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Hua-yang Huang , Yong-liang Ou , Ping-yue Li , Tao Zhang , Shuai Chen , Hong-yuan Shen , Qing Wang , Xiao-fei Zheng
      Background Single-tunnel double-bundle (STDB) anterior cruciate ligament (ACL) reconstruction can restore biomechanical function and anatomic structure, but existing methods of graft fixation are not adequate. The aims of this study are to examine knee biomechanics after STDB reconstruction using a unique expandable interference screw for fixation. Methods The biomechanical parameters of six pairs of human cadaveric knee specimens were measured with the ACL intact, after ACL removal, and after STDB reconstruction using the interference screw or single-tunnel single-bundle (STSB) reconstruction. Anterior tibial translation under 134N anterior tibial load in a neutral position as well as in 15° and 30° internal and external knee rotation and the internal tibial rotation angle under the rotatory load (5N·m internal tibial rotation) were measured. Results Anterior tibial translations at each degree of knee flexion in the STDB group were significantly less than in the STSB group (all, P <0.05). The internal rotation angles in the STSB group at five flexion angles were significantly higher than in the ACL intact group, whereas there were significantly less than those of the ACL absent group (P <0.05). Under rotatory loads in the neutral position, the tibial internal rotation angles of the STDB group were significantly lower than in the STSB group at all flexion angles (all, P <0.05). Conclusions STDB ACL reconstruction with the expandable interference screw provides better anteroposterior and rotational stability than STSB reconstruction. Clinical relevance The technique provides the advantages of double-bundle reconstruction using a single-tunnel technique.


      PubDate: 2014-04-07T16:20:09Z
       
  • A novel technique, dynamic intraligamentary stabilization creates optimal
           conditions for primary ACL healing: A preliminary biomechanical study
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Sandro Kohl , Dimitrios S. Evangelopoulos , Sufian S. Ahmad , Heindrik Kohlhof , Gudrun Herrmann , Harald Bonel , Stefan Eggli
      Background Anterior cruciate ligament (ACL) rupture is a common lesion. Current treatment emphasizes arthroscopic ACL reconstruction via a graft, although this approach is associated with potential drawbacks. A new method of dynamic intraligamentary stabilization (DIS) was subjected to biomechanical analysis to determine whether it provides the necessary knee stability for optimal ACL healing. Methods Six human knees from cadavers were harvested. The patellar tendon, joint capsule and all muscular attachments to the tibia and femur were removed, leaving the collateral and the cruciate ligaments intact. The knees were stabilized and the ACL kinematics analyzed. Anterior–posterior (AP) stability measurements evaluated the knees in the following conditions: (i) intact ACL, (ii) ACL rupture, (iii) ACL rupture with primary stabilization, (iv) primary stabilization after 50 motion cycles, (v) ACL rupture with DIS, and (vi) DIS after 50 motion cycles. Results After primary suture stabilization, average AP laxity was 3.2mm, which increased to an average of 11.26mm after 50 movement cycles. With primary ACL stabilization using DIS, however, average laxity values were consistently lower than those of the intact ligament, increasing from an initial AP laxity of 3.00mm to just 3.2mm after 50 movement cycles. Conclusions Dynamic intraligamentary stabilization established and maintained close contact between the two ends of the ruptured ACL, thus ensuring optimal conditions for potential healing after primary reconstruction. The present ex vivo findings show that the DIS technique is able to restore AP stability of the knee.


      PubDate: 2014-04-07T16:20:09Z
       
  • Arthroscopic treatment of tibial spine fracture in children with a
           cannulated Herbert screw
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): N. Wiegand , I. Naumov , L. Vámhidy , L.G. Nöt
      Background Avulsion fractures of the anterior tibial intercondylar eminence in childhood are rare and are severe injuries of the knee. Since the injury is equivalent in aetiology with ruptures of the anterior cruciate ligament, the treatment requires anatomic reduction and preservation of the stability of the joint. The aim of the study was to demonstrate our experiences with the arthroscopy-guided Herbert-screw fixation in the treatment of displaced tibial eminence fractures in children. Methods Between January 2004 and December 2011, a total of eight children were treated surgically with Type II or Type III anterior tibial eminence fractures; another four children with undisplaced, Type I fractures were treated conservatively, applying with cast fixation for 6weeks. Radiological consolidation, stability and functional outcome were assessed during the follow-up examinations. Results On the 12th postoperative week, we did not find instability in any of the patients by physical examination. There were only minimal differences found in the functional outcome, comparing the conservatively and operatively treated groups (Lysholm functional scale, average scores: Type I: 97, Type II: 95 and Type III: 94 points). The range of motion (ROM) of the injured knees was identical with healthy sides on the postoperative 6th week. Conclusions Our results indicate that the presented method can successfully be applied in the treatment of displaced tibial spine fractures; providing excellent stability and preserving the function of the injured knee in the short-term.


      PubDate: 2014-04-07T16:20:09Z
       
  • Diagnostic test accuracy of clinical and radiological assessments for
           medial patella plica syndrome: A systematic review and meta-analysis
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Nicholas Stubbings , Toby Smith
      Background The diagnosis of medial patella plica (MPP) syndrome is challenging due to poor clinical knowledge and controversies surrounding clinical and radiological diagnosis. The purpose of this study is to determine the diagnostic accuracy of clinical tests and radiological imaging in the detection of MPP syndrome. Methods A systematic review of the electronic databases EMBASE, MEDLINE, Science Direct and Scopus was undertaken. All studies which compared the accuracy of a clinical test, magnetic resonance imaging (MRI) or ultrasound (USS) (index tests) to assess the presence of MPP syndrome, against a surgical procedure (reference test) were included. Methodological appraisal using the QUADAS tool was conducted. The data was analyzed with pooled sensitivity and specificity meta-analyses with 95% confidence intervals. Results Seven studies including 492 knees were reviewed. The MPP (physical examination) test (sensitivity=0.90; specificity=0.89) and USS (sensitivity=0.90; specificity=0.83) demonstrated the greatest diagnostic test accuracy. MRI demonstrated a sensitivity of 0.77 and specificity of 0.58. The literature presented with moderate methodological quality. Conclusions The MPP test and USS are valuable in the diagnosis of MPP syndrome. The reference standard for future research in this area should be the resolution of symptoms following MPP resection, instead of arthroscopic evaluation. Level of Evidence 3a


      PubDate: 2014-04-07T16:20:09Z
       
  • Quantifying the excess cost and resource utilisation for patients with
           complications associated with elective knee arthroscopy: A retrospective
           cohort study
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Megan A. Bohensky , Zanfina Ademi , Richard deSteiger , Danny Liew , Vijaya Sundararajan , Andrew Bucknill , Chris Kondogiannis , Caroline A. Brand
      Background Recent studies have demonstrated morbidity associated with elective knee arthroscopy. The objective of the current study was to quantify resource utilisation and costs associated with postoperative complications following an elective knee arthroscopy. Methods We undertook a retrospective, longitudinal cohort study using routinely collected hospital data from Victorian public hospitals during the period from 1 July 2000 to 30 June 2009. A generalised linear model was used to examine relative cost and length of stay for venous thromboembolism, joint complications and infections. Log-transformed multiple linear regression and retransformation were used to determine the excess cost after adjustment. Results We identified 166,770 episodes involving an elective knee arthroscopy. There were a total of 976(0.6%) complications, including 573 patients who had a venous thromboembolism (VTE) (0.3%), 227 patients with a joint complication (0.1%) and 141 patients with infections (0.1%). After adjustment, the excess 30-day cost per patient for venous thromboembolism was $USD +3227 (95% CI: $3211–3244), for joint complications it was $USD +2247 (95% CI: $2216–2280) and for infections it was $USD +4364 (95% CI: $4331–4397). Conclusion This is the first study to quantify resource utilisation for complications associated with elective knee arthroscopy. With growing attention focused on improving patient outcomes and containing costs, understanding the nature and impact of complications on resource utilisation is important.


      PubDate: 2014-04-07T16:20:09Z
       
  • Epidemiology of hospitalised osteochondritis dissecans in young people:
           Incidence, geographical variation and trends over time in England from
           2002 to 2010
    • Abstract: Publication date: March 2014
      Source:The Knee, Volume 21, Issue 2
      Author(s): Oisin J.F. Keenan , Philip G. Turner , David Yeates , Michael J. Goldacre
      Background Osteochondritis dissecans (OCD) is an important cause of knee pain in physically active adolescents, but its aetiology remains controversial. Modern data on its epidemiology are lacking. The aim of this study was to analyse the hospitalised incidence, age and sex distribution, trends over time and geographical variation in OCD in the whole of England. Methods Hospital episode statistics (HES) data were analysed for OCD over the period 2002/3 to 2010/11 for England. HES datasets were record-linked so that anyone with multiple admissions for OCD was counted once only. Results The annual incidence rate for hospitalised OCD was 1.58 (95% CI 1.51–1.64) cases per 100,000 population. The peak age at diagnosis was 15–19years for both sexes, and boys were affected more commonly than girls in the ratio 2:1. The hospitalised incidence of OCD varied significantly across England by government office region, from 1.05 (0.91–1.20) in London to 1.89 (1.70–2.09) in the North West Region. Conclusions These data on the epidemiological features and trends over time in OCD provide new information about its basic epidemiological distribution. Its annual hospitalised incidence is about 1.6 cases per 100,000 population under 25years, but varies significantly across England. These results have implications for planning rheumatology and orthopaedic services for both children and adults.


      PubDate: 2014-04-07T16:20:09Z
       
  • Corrigendum to “Minimally invasive total knee arthroplasty: A
           pragmatic randomised controlled trial reporting outcomes up to 2year
           follow up” [Knee 21 (1) (2014) 189–193]
    • Abstract: Publication date: Available online 27 March 2014
      Source:The Knee
      Author(s): A. Tasker , M. Hassaballa , J. Murray , S. Lancaster , N. Artz , W. Harries , A. Porteous



      PubDate: 2014-03-28T06:24:20Z
       
  • Efficacy of Passive Extension Mobilization in Addition to Exercise in the
           Osteoarthritic Knee: An observational parallel-group study
    • Abstract: Publication date: Available online 27 March 2014
      Source:The Knee
      Author(s): Olaf Kappetijn , Emiel van Trijffel , Cees Lucas
      Study design Pretest-posttest observational parallel-group design. Objectives To evaluate the efficacy of passive knee extension mobilization in addition to exercise therapy on extension range of motion (ROM) in patients with osteoarthritis (OA) of the knee. Secondary objectives were to determine changes in pain and functional abilities. Background Patients with knee OA complain of pain, limited range of motion, and impaired activities. Efficacy of mobilization as a treatment option next to exercises has not been studied rigorously. Methods and Measures Thirty-four participants with persistent knee pain, a positive radiography for knee OA, and a passive extension deficit were included. Seventeen participants (mean age±SD, 59.8±6.1years) were treated with an exercise protocol and were additionally given manual mobilizations to improve passive extension ROM. The other group (mean age±SD, 61.5±7.3years) with equal characteristics was treated with an identical exercise therapy protocol only. Prior to participation, detailed ROM measurements were recorded next to muscle function tests, pain (VAS), six-minute walking tests (6MWT), a condition-specific questionnaire, and the patient-specific function scale (PSFS). Participants in both groups completed 16 treatment sessions each. Results Passive mobilizations significantly improved extension ROM in the intervention group (5.2 versus 8.6 degrees, p=.017). The manually mobilized group also had better physical capacities as assessed by 6MWT, less pain, and a lower PSFS score. Conclusion A combined protocol including exercise therapy and passive mobilization was beneficial for patients with OA of the knee complaining of pain, decreased extension ROM and decreased limited abilities. Level of evidence Therapy, 2b.


      PubDate: 2014-03-28T06:24:20Z
       
  • Plateau-Patella Angle in Evaluation of Patellar Height in Osteoarthritis
    • Abstract: Publication date: Available online 20 March 2014
      Source:The Knee
      Author(s): Matthew Ellington , Brett Robin , Daniel Jupiter , Bryce Allen
      Background The plateau-patella angle (PPA), recently introduced as a new and simpler method of measuring patellar height from the lateral radiograph, has the advantage of simplicity over previously described methods as it involves a single angular measurement without the need for calculations. The purpose of this study was to validate the use of the PPA as a measurement for patellar height in knees with moderate to severe osteoarthritis. Methods A total of 331 patients who underwent total knee arthroplasty at our institution with radiographs prior to surgery were evaluated. Of those, 297 (89.2%) were felt to be adequate for review. Three observers with different levels of orthopedic training measured PPA, Insall-Salvati, Caton-Deschamps, and Blackburne-Peele indices on a subset of 50 consecutive patients. Interobserver agreement for each of the four measurements was calculated and correlation between each of the measurements within each observer was calculated. The measurement of the PPA was repeated. Intraobserver agreement for the PPA was determined and a normal range and distribution was defined for this population. Results For the three observers, the mean PPA for the entire cohort was 25.55, 25.31, and 24.42. The intraclass correlation coefficient (ICC) was 0.81, The ICC and intraobserver assessment were highest for the PPA compared with the other ratios. The PPA was found to correlate most strongly with the Blackburne-Peel method. Conclusions The plateau-patella angle is a reliable way to evaluate patellar height in the osteoarthritic population. The measurement demonstrated a higher interobserver reliability compared with previously described methods. Level of eviden Retrospective Level IV


      PubDate: 2014-03-23T07:21:26Z
       
  • Knee biomechanics during popular recreational and daily activities in
           older men
    • Abstract: Publication date: Available online 19 March 2014
      Source:The Knee
      Author(s): Julie L. Pfeiffer , Songning Zhang , Clare E. Milner
      Background Physical activity is recommended for older adults, including those with knee pathology. However, demands on the knee during popular recreational activities are unclear. The study purpose was to determine knee biomechanics in healthy older men during golf and bowling and compare them to activities of daily living. Methods Three-dimensional motion analysis was used to determine knee biomechanics in 19 healthy males (45–73years): 11 golfers and eight bowlers. Subjects performed walking, stair ascent, stair descent, and either golf or bowling. Comparisons were made between the recreational activity and activities of daily living. Results During bowling, flexion angle at peak extensor moment was as high as during stair descent, and peak extensor moment was as high as during stair ascent. For the golf lead knee, flexion angle at peak extensor moment and peak extensor moment were as high as during stair ascent, and peak abduction moment, internal and external rotation angles were larger than during all activities of daily living. Peak external rotation angle for the golf trail knee was larger than all activities of daily living. Conclusion The greatest challenge for the knee of healthy older males during bowling is eccentric control of knee flexion. Golf poses challenges in all three planes of motion for the lead knee and in the transverse plane for the trail knee. Clinical Relevance Comparing mechanical demands on the knee during bowling and golf to those of stair negotiation provides a reference for clinicians when recommending recreational activities for older adults with knee pathology.


      PubDate: 2014-03-23T07:21:26Z
       
  • Effect of lower limb malalignment in the frontal plane on transverse plane
           mechanics during gait in young individuals with varus knee alignment
    • Abstract: Publication date: Available online 20 March 2014
      Source:The Knee
      Author(s): Felix Stief , Harald Böhm , Chakravarthy U. Dussa , Christel Multerer , Ansgar Schwirtz , Andreas B. Imhoff , Leonhard Döderlein
      Background Varus knee alignment has been identified as a risk factor for the progression of medial knee osteoarthrirtis (OA). This study tested the hypothesis that not only frontal plane kinematics and kinetics but also transverse plane lower extremity mechanics during gait are affected by varus malalignment of the knee. Methods Eighteen, otherwise healthy children and adolescents with varus malalignment of the knee were studied to examine the association between static varus malalignment and functional gait parameters. Kinematic data were collected using a Vicon motion capture system (VICON Motion Systems, Oxford, UK). Two AMTI force plates (Advanced Mechanical Technology, Inc., Watertown, MA, USA) were used to collect kinetic data. Results The results indicated that changes in transverse plane mechanics occur concomitantly with changes in knee malalignment in the frontal plane. A mechanical consequence of varus knee malalignment is obviously an increased endorotation of the foot (internal foot placement) and an increased internal knee rotation (tibia rotation) during stance phase. The linear correlation between the maximum external knee adduction moment in terminal stance and the internal knee rotation in terminal stance (r=0.823, p<0.001) shows that this transverse plane gait mechanics is directly in conjunction with intrinsic compressive load on the medial compartment during gait. Conclusions Understanding factors that influence dynamic knee joint loading in healthy, varus malaligned knees may help us to identify risk factors that lead to OA. Thus, three-dimensional gait analysis could be used for clinical prognoses regarding the onset or progression of medial knee OA.


      PubDate: 2014-03-23T07:21:26Z
       
  • Screw loosening and iliotibial band friction after posterolateral corner
           reconstruction
    • Abstract: Publication date: Available online 13 March 2014
      Source:The Knee
      Author(s): Camilo Partezani Helito , Marcelo Batista Bonadio , Marco Kawamura Demange , Roberto Freire da Mota Albuquerque , José Ricardo Pécora , Gilberto Luis Camanho , Fábio Janson Angelini
      Background Many reconstruction techniques have already been developed for treating posterolateral corner (PLC) injuries, with still no consensus regarding what would be the best option. Some of them use non-bone tunnel fixation, attaching the graft to the femur using a cortical screw with toothed washer. The main objective of the present study is to evaluate complications related to fixation performed by screw and toothed washer technique. Methods A prospective study with surgical reconstruction of the PLC structures of the knee between January 2008 and December 2009 was performed. PLC reconstruction included reconstruction of the lateral collateral ligament, popliteofibular ligament and popliteal muscle tendon. Fixation of the grafts in the femur was achieved by means of a 4.5mm screw with a toothed washer. The assessments were done using the following methods: objective IKDC, subjective IKDC, Lysholm and Tegner. Radiographic evaluations were performed immediately after the operation, at three, six and twelve months after surgery, and yearly thereafter. Complications were documented. Results The mean subjective IKDC score after the operation was 69.2, Lysholm scale was 80.7. Two patients presented failure of reconstructions of the PLC. In the radiographic evaluations, signs of loosening of the screw with toothed washer in the femur were observed in eight cases (66.6%). Six patients(50%) complained of lateral pain after the operation. Conclusion The technique of femoral fixation shown to be efficient to restoration of stability. However there was a high rate of complications secondary to implant, such as loosening of the screws and iliotibial tract friction.


      PubDate: 2014-03-18T07:20:27Z
       
  • Efficacy and safety of single-dose local infiltration of analgesia in
           total knee arthroplasty: A meta-analysis of randomized controlled trials
    • Abstract: Publication date: Available online 13 March 2014
      Source:The Knee
      Author(s): Chang-Peng Xu , Xue Li , Zhi-Zhong Wang , Jin-Qi Song , Bin Yu
      Purpose To examine the efficacy and safety of single-dose local infiltration of analgesia (LIA) for post-operative pain relief in total knee arthroplasty (TKA) patients. Methods A systematic electronic literature search (up to Aug 2013) was conducted to identify the RCTs that addressing the efficacy and safety of single-dose LIA in the pain management after TKA. Subgroup analysis was conducted to determine changes of visual analog scores (VAS) values at six different postoperative time points. Weighted mean differences or relative risks with accompanying 95% confidence intervals were calculated and pooled using a random effect model. Results Eighteen trials involving 1,858 TKA patients met the inclusion criteria. The trials were liable to medium risk of bias. The VAS values at postoperative 2h, 4h, 6h, 12h, 24h, 48h per patient were significantly lower in the LIA group than in the placebo group, and the former group also had less morphine consumption and better early functional recovery including range of motion, time to straight leg raise and 90° knee flexion than the latter group. No significant difference in length of hospital stay or side effects was detected between the two groups. Conclusions The current evidence shows that use of single-dose LIA is effective for postoperative pain management in TKA patients, with satisfactory short-term safety. More high-quality RCTs with long-term follow-ups are highly required for examining the long-term safety of single-dose LIA. Level of evidence I, II.


      PubDate: 2014-03-18T07:20:27Z
       
  • Clinical Alignment Variations in Total Knee Arthroplasty with Different
           Navigation Methods
    • Abstract: Publication date: Available online 12 March 2014
      Source:The Knee
      Author(s): Byron F. Stephens , Sam Hakki , Khaled J. Saleh , William M. Mihalko
      Background We compared the resulting alignment in 90 degrees of flexion and in full extension after total knee arthroplasty (TKA) with two navigation systems using different techniques: a measured resection (MR) system and a gap-balancing (GB) system. Methods Varus and valgus alignment in extension and flexion were compared in 100 consecutive patients who had TKA with an MR distal-femoral-cut-first technique at one institution and 100 consecutive patients in whom a GB tibial-cut-first technique was used at another institution. Alignment deviation of 3 degrees or more from neutral was considered an outlier. Results No significant difference between the groups in coronal alignment in extension or flexion was found, but there were three times the number of outliers for clinical alignment in flexion for the MR group compared to the GB group. Conclusions The use of the GB tibial-cut-first computer-assisted TKA navigation may provide a more consistent clinical alignment in flexion than systems using an MR technique. Level of Evidence Therapeutic study. Level 2.


      PubDate: 2014-03-13T07:20:36Z
       
  • Double Bundle PCL Reconstruction Using Autogenous Quadriceps Tendon and
           Semitendinous Graft: Surgical Technique with Two-Year Follow-up Clinical
           Results
    • Abstract: Publication date: Available online 5 March 2014
      Source:The Knee
      Author(s): Ricardo de Paula Leite Cury , Marcos Barbieri Mestriner , Camila Cohen Kaleka , Nilson Roberto Severino , Victor Marques de Oliveira , Osmar Pedro Arbix Camargo
      Objectives To evaluate the results obtained of PCL reconstruction with the double femoral tunnel technique, using quadriceps tendon and semitendinous autograft, in patients with isolated PCL tears or PCL tears associated with other ligament lesions, two years after surgery. Methods 14 patients with isolated PCL lesions and 20 with combined ligament lesions, underwent PCL reconstruction using the double femoral tunnel technique, and were evaluated 24months after surgery using the IKDC and Lysholm scores, KT1000 and the graduation of the posterior drawer test. Results knees were considered normal (“A”) or nearly normal (“B”) in 92,9% of patients with isolated lesions and in 95,0% of patients with combined tears, according to the IKDC score. Good or excellent results were obtained in 100% of patients in both groups according to the Lysholm score. Absence or outstanding reduction of posterior tibial translation was seen in 92,9% of patients with isolated lesions and in 100% of patients with combined ligament tears, in the posterior drawer evaluation. Conclusion The PCL double femoral tunnel reconstruction technique using autografts was effective in restoring posterior knee stability, in isolated and or combined PCL tears, showing remarkable clinical improvement in all patients. Level of evidence: 2C


      PubDate: 2014-03-08T07:18:37Z
       
  • Letter to the Editor
    • Abstract: Publication date: Available online 5 March 2014
      Source:The Knee
      Author(s): Thomas Joyce , David Deehan



      PubDate: 2014-03-08T07:18:37Z
       
  • The Influence of tibial morphology on the design of an anatomical tibial
           base plate for TKA
    • Abstract: Publication date: Available online 20 January 2014
      Source:The Knee
      Author(s): Maximilian J. Hartel , Yannick Loosli , Daniel Delfosse , Peter Diel , Michael Thali , Steffen Ross , Sandro Kohl , Stefan Eggli
      Background Finding the right balance between tibial coverage and minimal implant overhang is an important factor in TKA. Another significant cause of failure is component malrotation. Methods An average master shape of the proximal tibia at TKA resection level was calculated using fine slice computed tomographies of 117 cadaveric knees. To find out whether alternate implant contours would be necessary depending on the patient’s body size, we established five subgroups to compare. CAD-Analysis was performed to simulate the overhang produced after ±4°/±7°/±10° rotation. Results A master shape for the tibial resection cut (with a 5° posterior slope, 7mm under lateral joint line) could be determined. Neither left vs. right knee joint, nor male vs. female nor the size subdivision appear to alter the calculated master shape significantly. The optimized shape allowing for ±4° of rotational freedom was found to be the best variant. Conclusions Valid methods have been obtained to design a two-dimensional average shape of the tibial plateau. The modifications described in this study might come in useful, when designing future implant designs. Clinical relevance An optimized fit at the tibial plateau and lower rates of component malrotation may result in better outcomes after TKA.


      PubDate: 2014-01-23T04:35:18Z
       
 
 
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