for Journals by Title or ISSN
for Articles by Keywords
help
  Subjects -> BIOLOGY (Total: 2766 journals)
    - BIOCHEMISTRY (210 journals)
    - BIOENGINEERING (86 journals)
    - BIOLOGY (1363 journals)
    - BIOPHYSICS (47 journals)
    - BIOTECHNOLOGY (160 journals)
    - BOTANY (211 journals)
    - CYTOLOGY AND HISTOLOGY (25 journals)
    - ENTOMOLOGY (56 journals)
    - GENETICS (145 journals)
    - MICROBIOLOGY (232 journals)
    - MICROSCOPY (10 journals)
    - ORNITHOLOGY (27 journals)
    - PHYSIOLOGY (68 journals)
    - ZOOLOGY (126 journals)

BIOLOGY (1363 journals)            First | 7 8 9 10 11 12 13 14     

The end of the list has been reached. Please navigate to previous pages.

  First | 7 8 9 10 11 12 13 14     

Journal Cover   The Knee
  [SJR: 1.137]   [H-I: 44]   [15 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0968-0160
   Published by Elsevier Homepage  [2588 journals]
  • Case series report: Early cement–implant interface fixation failure
           in total knee replacement
    • Abstract: Publication date: Available online 17 March 2015
      Source:The Knee
      Author(s): Kyle J. Hazelwood , Michael O’Rourke , Van P. Stamos , Robert D. McMillan , David Beigler , William J. Robb III
      Background Early failure in cemented total knee replacement (TKR) due to aseptic loosening is uncommon. A small number of early failures requiring revision were observed at one hospital due to observed cement–implant fixation failure. The purpose of this case series is to report and identify possible causes for these early failures. Methods Between May 2005 and December 2010, 3048 primary TKRs were performed over a 5-year period of time by six surgeons. Two total knee systems were used during this period of time. Nine early failures were observed in eight patients. High viscosity cement (HVC) was used in all these cases. Results Aseptic loosening of the tibial component was observed in all nine early total knee failures. The high viscosity bone cement was noted to be non-adherent to the tibial trays at the time of revision surgery. HVC was used in all these cases. Conclusions Properties of HVC may contribute to make it more susceptible to early failure in a small number of TKRs. HVC in total hip replacement (THR) has been associated with cement micro-fractures, cement debris generation and early implant failure. The mechanical properties of HVC may similarly contribute to early failure at the cement–implant interface in a small percentage TKRs.


      PubDate: 2015-03-19T22:01:03Z
       
  • Bioabsorbable interference screw failure in anterior cruciate ligament
           reconstruction: A case series and review of the literature
    • Abstract: Publication date: Available online 17 March 2015
      Source:The Knee
      Author(s): Jonathan N. Watson , Peter McQueen , Walter Kim , Mark R. Hutchinson
      Background To report a case series of failures of bioabsorbable interference screws with possible identification of a novel failure mechanism. Methods A retrospective review of ACL reconstructions by the senior author utilizing BioComposite™ Interference Screws (Arthrex, Inc., Naples, FL) was performed. Complications related to screw placement, including fracture, breakage or bending were examined. Our rate and methods of failure were compared to those quoted in the current literature. Results Eighty-seven patients of average age 23.8years met inclusion criteria. There were eight screw failures in six patients, with femoral failure in seven and tibial failure in one. The femoral screw fractured halfway between the tip and head in five, while the head of the screw broke in one and the screw bent in another. In the case of tibial interference screw fracture, failure occurred halfway between the tip and head. The insertion device that was used was replaced after recognition of material deformation and considered a potential contributor to the breakage risk as no further screw failures have occurred since. Conclusions We demonstrate a unique failure mechanism of bio-absorbable interference screws. In each case, the reconstruction was salvaged. Regular inspection of materials and implants can ensure optimal outcomes and decrease complications intra-operatively.


      PubDate: 2015-03-19T22:01:03Z
       
  • Evaluation of a behind-remnant approach for femoral tunnel creation in
           remnant-preserving double-bundle anterior cruciate ligament reconstruction
           — Comparison with a standard approach
    • Abstract: Publication date: Available online 17 March 2015
      Source:The Knee
      Author(s): Hideyuki Koga , Takeshi Muneta , Kazuyoshi Yagishita , Toshifumi Watanabe , Tomoyuki Mochizuki , Masafumi Horie , Tomomasa Nakamura , Koji Otabe , Ichiro Sekiya
      Purpose To evaluate a novel approach for femoral tunnel creation, a behind-remnant approach, in remnant-preserving double-bundle anterior cruciate ligament (ACL) reconstruction through comparison with a standard approach. Methods Sixty patients who underwent remnant-preserving double-bundle ACL reconstruction were included. Thirty patients with a standard approach were classified as the standard group, and 30 patients with a behind-remnant approach as the behind-remnant (BR) group. The anteromedial bundle (AMB) and posterolateral bundle (PLB) were provisionally fixed at 20° and 45° of flexion to a graft tensioning system during surgery. Bundle tension was recorded during knee flexion–extension and in response to anterior or rotatory loads. Femoral tunnel positions were then assessed using the quadrant method. Results During flexion–extension, the BR group showed equivalent tension curves between AMB and PLB, while the standard group showed reciprocal tension curves. The tension on the PLB was lower than the AMB in response to anterior or rotatory loads in the BR group, while the AMB and PLB shared equivalent loads in the standard group. Tunnel position of the AMB in the BR group was lower and deeper, with smaller variances, than that in the standard group. Tunnel position of the PLB in the BR group was lower than that in the standard group. Conclusions In remnant-preserving double-bundle ACL reconstruction, a behind-remnant approach can be achieved without any removal of the remnant tissue, and could create a deeper and lower AMB tunnel and a lower PLB tunnel with higher reproducibility, showing equivalent tension curves between the AMB and PLB.


      PubDate: 2015-03-19T22:01:03Z
       
  • Contribution of geometric design parameters to knee implant performance:
           Conflicting impact of conformity on kinematics and contact mechanics
    • Abstract: Publication date: Available online 17 March 2015
      Source:The Knee
      Author(s): Marzieh M. Ardestani , Mehran Moazen , Zhongmin Jin
      Background Articular geometry of knee implant has a competing impact on kinematics and contact mechanics of total knee arthroplasty (TKA) such that geometry with lower contact pressure will impose more constraints on knee kinematics. The geometric parameters that may cause this competing effect have not been well understood. This study aimed to quantify the underlying relationships between implant geometry as input and its performance metrics as output. Methods Parametric dimensions of a fixed-bearing cruciate retaining implant were randomized to generate a number of perturbed implant geometries. Performance metrics (i.e., maximum contact pressure, anterior–posterior range of motion [A-P ROM] and internal–external range of motion [I-E ROM]) of each randomized design were calculated using finite element analysis. The relative contributions of individual geometric variables to the performance metrics were then determined in terms of sensitivity indices (SI). Results The femoral and tibial distal or posterior radii and femoral frontal radius are the key parameters. In the sagittal plane, distal curvature of the femoral and tibial influenced both contact pressure, i.e., SI=0.57; SI=0.65, and A-P ROM, i.e., SI=0.58; SI=0.6, respectively. However, posterior curvature of the femoral and tibial implants had a smaller impact on the contact pressure, i.e., SI=0.31; SI=0.23 and a higher impact on the I-E ROM, i.e., SI = 0.72; SI=0.58. It is noteworthy that in the frontal plane, frontal radius of the femoral implant impacted both contact pressure (SI=0.38) and I-E ROM (SI=0.35). Conclusion Findings of this study highlighted how changes in the conformity of the femoral and tibial can impact the performance metrics.


      PubDate: 2015-03-19T22:01:03Z
       
  • Kinematic analysis of knee varus and rotation movements at the initial
           stance phase with severe osteoarthritis of the knee
    • Abstract: Publication date: Available online 18 March 2015
      Source:The Knee
      Author(s): Takashi Fukaya , Hirotaka Mutsuzaki , Yasuyoshi Wadano
      Background The purposes of this study were to understand the kinematics changes in the frontal and horizontal planes with severe medial knee OA at the stance phase and to examine the relationship between varus and rotational movements. Methods The OA group comprised 18 knees in 12 subjects (five men, seven women) with a Kellgren–Lawrence grade of three or four in at least one knee. From the results of gait analysis, we calculated Spearman rank-correlation coefficients for the following items: varus angle at initial contact (IC); varus angle at loading response (LR); amount of varus thrust from IC to LR; rotational angle at IC; rotational angle at LR and amount of rotational angle change from IC to LR. Results The results indicated that, as the external rotation angle at IC and internal rotational movement from IC to LR increased, the maximum varus angle to LR showed a tendency to become large. In addition, varus thrust showed a tendency to become larger as the external rotation angles increased at IC and LR. The subjects with severe knee OA showed a strong correlation between the knee varus angle at IC and at LR. Furthermore, an increase in movement to internal rotation of the knee during the initial stance phase increased the knee varus angle at LR. Conclusions The control of the rotational movement according to the extent of varus thrust during the initial stance phase may have possible effects to decrease the load on the medial compartment of the knee.


      PubDate: 2015-03-19T22:01:03Z
       
  • The effect of coordinate system variation on in vivo patellofemoral
           kinematic measures
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2
      Author(s): Angela E. Kedgley , Emily J. McWalter , David R. Wilson
      Background The use of different coordinate system definitions for the patella leads to difficulties in comparing kinematic results between studies. The purpose of this work was to establish the effect of using a range of coordinate system definitions to quantify patellar kinematics. Additionally, intra- and inter-investigator repeatabilities of the digitization of anatomic landmarks on the patella were determined. Methods Four different patellar coordinate system definitions were applied using digitisations in two and three dimensions and a single femoral coordinate system was used for comparison. Intra-investigator variability was established by having one investigator digitize the patellar landmarks of three subjects on five separate occasions. Inter-investigator variability was quantified by having five participants digitize the same landmarks on the same three subjects. Patellofemoral kinematics were quantified for ten subjects, at six angles of tibiofemoral flexion, using MRI. Results As a result of changes in the patellar coordinate system, differences of up to 11.5° in flexion, 5.0° in spin, and 27.3° in tilt were observed in the resultant rotations for the same motion, illustrating the importance of standardizing the coordinate system definition. Conclusions To minimize errors due to variability while still maintaining physiologically sensible kinematic angles, a coordinate system based upon an intermediate flexion axis between the most medial and lateral points on the patella, and a superiorly-directed long axis located between the most proximal and distal points on the patella, with an origin at the centre of the most proximal, distal, medial, and lateral points on the patella is recommended. Clinical Relevance The recommended anatomic coordinate frame may be employed in the calculation of dynamic in vivo patellar kinematics when used in combination with any method that reliably quantifies patellar motion.


      PubDate: 2015-03-15T21:50:44Z
       
  • Knee arthroplasty with a medial rotating total knee replacement. Midterm
           clinical findings: A district general experience of 38 cases
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2
      Author(s): Sam C. Jonas , Miltiadis Argyropoulos , Nawfal Al-Hadithy , Marius Korycki , Benedict Lotz , Sunny D. Deo , Venkat Satish
      Background The Medial Rotating Knee replacement (MRK) was first used in 1994, reporting high rates of satisfaction. It is designed to replicate natural knee kinematics and improve stability and function. There are limited studies on the mid-term clinical outcomes, in particular in a district general hospital (DGH) environment. This is the first study that we are aware of that evaluates the learning curve of the implementation of this knee system in this environment. Patients/method Between 2007 and 2009 we performed 38 consecutive MRK replacements (MAT ORTHO, UK) in 36 patients. The mean follow-up was fouryears. Patients were evaluated clinically, using OKS and patient questionnaire and radiographically (good/acceptable/poor) to assess outcome. Results Mean age was 73.0years. Mean pre-operative OKS was 17.7 (range 8–29), which rose to 38.1 (range 23–48) at latest follow up (p<0.005). Overall 71% of the patients were either satisfied (29%) or very satisfied (42%). 81% felt an improvement of the ability to go up or down stairs and 92% felt stable. All poor radiographic and the majority of acceptable outcomes were experienced in the first 50% of cases. Conclusion The MRK can be successfully implanted in a DGH environment. It improves pain and function comparably to standard TKRs, however, subjective improvement may be higher. Radiographic evaluation shows an acceptable learning curve. Level of evidence Level IV case series.


      PubDate: 2015-03-15T21:50:44Z
       
  • Pain experience and functional outcome of inpatient versus outpatient
           anterior cruciate ligament reconstruction, an equivalence randomized
           controlled trial with 12months follow-up
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2
      Author(s): K.P. Valkering , C.J.A. van Bergen , G.A. Buijze , P.H.A.F. Nagel , W.E. Tuinebreijer , R.S. Breederveld
      Background Arthroscopic reconstruction of the anterior cruciate ligament (ACL) has traditionally been performed in an inpatient setting. Outpatient treatment may offer the advantages of cost reduction and higher patient satisfaction. Hypothesis/purpose We investigated whether ACL reconstruction in an outpatient setting is equally safe as in an inpatient setting and whether comparable functional outcomes can be achieved. We hypothesized that the outcomes of outpatient ACL reconstruction result in similar outcomes as inpatient ACL reconstruction. Study design A prospective randomized controlled trial was conducted at one centre. Methods Forty-six patients were randomized to outpatient treatment or a 2-day admission after ACL reconstruction. The functional outcome was evaluated with the Lysholm, Tegner and International Knee Documentation Committee scores. Safety of the procedures was judged according to pain experience and readmission rate. The duration of follow-up was 1 year after ACL reconstruction. The patients were provided with a simple postoperative analgesic protocol. The linear mixed effect model for repeated measures was used for testing the differences between the study groups. Results No significant differences were found between the study groups in all the outcome measures. No readmissions were recorded related to pain. One complication was recorded in the outpatient group versus three in the inpatient group. Conclusion This study indicates that outpatient care after ACL reconstruction yields comparable functional results and postoperative pain experience as inpatient care and is a safe option. A simple analgesic protocol provides adequate pain relief during the postoperative phase. Level of evidence: I.


      PubDate: 2015-03-15T21:50:44Z
       
  • Editorial
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2
      Author(s): James B. Stiehl



      PubDate: 2015-03-15T21:50:44Z
       
  • Editorial Board
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2




      PubDate: 2015-03-15T21:50:44Z
       
  • Editorial Board
    • Abstract: Publication date: March 2015
      Source:The Knee, Volume 22, Issue 2




      PubDate: 2015-03-15T21:50:44Z
       
  • The risk of manipulation under anesthesia due to unsatisfactory knee
           flexion after fast-track total knee arthroplasty
    • Abstract: Publication date: Available online 9 March 2015
      Source:The Knee
      Author(s): Christian Wied , Morten G. Thomsen , Thomas Kallemose , Lis Myhrmann , Lotte S. Jensen , Henrik Husted , Anders Troelsen
      Background Fast-track TKA has significantly shortened the time available for physiotherapists to optimize knee ROM before discharge. Safety aspects concerning knee stiffness and the need for manipulation in a fast-track setting need to be illuminated. The study aims were to analyze if fast-track TKA can be considered safe considering rates of knee manipulation and if there is an association between knee ROM at time of discharge and the need for later manipulation. Methods Primary TKAs operated in 2011 at our institution were eligible for inclusion. The study group consisted of 359 TKAs. Results Manipulation of the knee was performed in 21 of 359 TKAs (5.8%). Seventy-one percent were discharged with a flexion ≥70° combined with an extension deficit of ≤10°. The occurrence of MUA for these patients was 4.3%. The prevalence of knee manipulation showed a statistically significant association with the achieved knee flexion at discharge (p=0.02). Median length of stay was two days. Conclusion Compared with literature findings fast-track TKA surgery may be considered safe based on the acceptable rate of knee manipulations after TKA (5.8%). We suggest ROM of ≥70° flexion combined with an extension deficit of ≤10° as an “optimal-zone” for ROM at discharge. The reason for this is the low occurrence of MUA (4.3%) in relation to the large amount of TKAs it represents (71%). The indication for MUA is multifactorial and ROM at discharge serves only as an indicator of later MUA risk.


      PubDate: 2015-03-11T20:59:07Z
       
  • Update on the etiology of revision TKA — Evident trends in a
           retrospective survey of 1449 cases
    • Abstract: Publication date: Available online 11 March 2015
      Source:The Knee
      Author(s): Tilman Calliess , Max Ettinger , Natalie Hülsmann , Sven Ostermeier , Henning Windhagen
      Background A working and complete knowledge of the different causes of dysfunction and pain after TKA is essential for the ability to correctly determine the cause of failure and to address this problem specifically. The purpose of this study was to update the etiology of implant failure. New diagnosis and current trends should be displayed. Methods All TKA revisions performed in our institution between 2001 and 2010 were reviewed retrospectively. Patient demographics and the precise indication for the surgery were documented. Descriptive statistical analyses and association analyses of both the diagnosis and patient demographics were performed. Results Within our collective of 1449 revision TKA a total of 40 different pathologies leading to revision surgery were identified and categorized. Overall 68.5% of the revisions were categorized aseptic, 31.5% as septic implant failure. Some recently debated diagnoses like low-grade-infection showed a high increase in incidence whereas classic failure mechanisms like polyethylene wear showed a decrease over the time. Conclusion We believe that this study successfully updates the current knowledge of different failure mechanisms in revision TKA, which have to be considered on dysfunction or pain after surgery. We were able to evaluate the clinical relevance of each pathology and could shift from implant related problems like wear to more surgical problems like instability and or malalignment over the last years. With a higher alertness to chronic low-grade-infections the incidence of infection is even increasing. Level of evidence Level II, economic and decision analysis.


      PubDate: 2015-03-11T20:59:07Z
       
  • A comparison of lateral fixation versus dual plating for simple bicondylar
           fractures
    • Abstract: Publication date: Available online 5 March 2015
      Source:The Knee
      Author(s): Yunfeng Yao , Hao Lv , Junfeng Zan , Jisen Zhang , Nan Zhu , Rende Ning , Juehua Jing
      Background The best fixation method for bicondylar tibial plateau fracture is debated. The aim of this study was to compare the effect of a lateral locking plate with that of dual plates in the treatment of tibial plateau fracture with a relatively intact medial condyle fragment. Methods Eighty-six patients diagnosed with a bicondylar tibial plateau fracture with a relatively intact medial condyle were assigned to groups treated with either dual buttress plates (DP group) or a lateral locking plate (LP group). Preoperative characteristics, surgical details, and postoperative complications were recorded and compared between groups. Hospital for Special Surgery Knee Scoring System score was used to evaluate clinical outcome. Results Both groups displayed satisfactory clinical and radiographic results. There were no significant differences in associated preoperative conditions between the DP and LP groups. Durations of hospital stay and operation were significantly shorter, and blood loss significantly less, in the LP group than in the DP group (P =0.045;0.038;0.031). The rate of delayed-union was significantly lower in the LP group than in the DP group (P =0.023). Conclusion Both dual-plate and lateral locking-plate fixation can provide satisfactory treatment of bicondylar tibial plateau fractures if properly used. When the medial tibial condyle is relatively intact, a lateral locking plate can provide stability similar to that of dual plate while decreasing operative duration and soft-tissue complications, which can assist fracture healing and shorten hospital stay. Level of evidence I — Randomized controlled trial.


      PubDate: 2015-03-07T20:45:24Z
       
  • Corrigendum to “Partial harvesting technique in anterior cruciate
           ligament reconstruction with autologous semitendinosus tendon to prevent a
           postoperative decrease in deep knee flexion torque” [The Knee 21
           (2014) 936–943]
    • Abstract: Publication date: Available online 3 March 2015
      Source:The Knee
      Author(s): Jun Sasahara , Masato Takao , Wataru Miyamoto , Kenji Oguro , Takashi Matsushita



      PubDate: 2015-03-03T20:23:20Z
       
  • A meta-analysis of bone–patellar tendon–bone autograft versus
           four-strand hamstring tendon autograft for anterior cruciate ligament
           reconstruction
    • Abstract: Publication date: Available online 11 December 2014
      Source:The Knee
      Author(s): Xiaobo Xie , Xuzhou Liu , Zhongran Chen , Yingdian Yu , Sheng Peng , Qi Li
      Background There is a lack of comprehensive studies comparing the clinical outcome of anterior cruciate ligament (ACL) reconstruction with either a bone–patellar tendon–bone (BPTB) or four-strand hamstring tendon (4SHT) autografts. The optimal choice of graft for anterior cruciate ligament reconstruction remains controversial. Purpose The objective of this study was to evaluate the effectiveness of BPTB autografts versus 4SHT autografts for the reconstruction of ACL. Methods A systematical search of literature was performed in Pubmed, Embase, and the Cochrane library to identify published clinical prospective studies relevant to ACL reconstruction comparing BPTB and 4SHT autografts. The results of the eligible studies were analysed in terms of instrumented laxity measurements, Lachman test, pivot shift test, objective International Knee Documentation Committee (IKDC) scores, return to preinjury activity level, and morbidity of graft failure, anterior knee pain, kneeling pain, extension deficit, and flexion deficit. Study quality was assessed by using the Jadad scale for randomized clinical trial (RCT) and the Newcastle–Ottawa Scale (NOS) for prospective cohort study (PCS). Two reviewers independently assessed each study for quality and extracted data. Subgroup analysis of the primary outcomes was conducted according to the type of study design (RCT or PCS). Results Twenty-two studies, with 931 patients in the BPTB group and 999 patients in the 4SHT group, met the inclusion criteria. Fourteen studies were randomized controlled trials, and eight were prospective cohort studies. The results of the meta-analysis showed that there were no significant differences between BPTB and 4SHT in terms of instrumented laxity measurements (P=0.06), Lachman test (P=0.58), objective IKDC scores (P=0.31), graft failure (P=0.45), extension deficit (P=0.06) and flexion deficit (P=0.63). However, outcomes in favour of BPTB were found in terms of pivot shift test (P=0.01) and return to preinjury activity level (P=0.03); outcome measures that favours 4SHT included anterior knee pain (P<0.01) and kneeling pain (P<0.01). These findings were still robust during the sensitivity analysis. Results from subgroup analysis of the primary outcomes were consistent with the overall analysis. Conclusion Based on the results above, ACL reconstruction with BPTB autografts might be superior in resuming rotation stability of the knee joint and allow patients to return to higher levels of activity in comparison with 4SHT autografts. Whereas, postoperative complications of the knee joint were lower for 4SHT autografts than for BPTB autografts. There was insufficient evidence to identify which of the two types of grafts was significantly better for ACL reconstruction considering the limitations of this study. More high-quality randomized controlled trials with strictly specified inclusion criteria are highly required before drawing a reliable conclusion.


      PubDate: 2015-02-27T20:12:56Z
       
  • Characterisation of in-vivo mechanical action of knee braces regarding
           their anti-drawer effect
    • Abstract: Publication date: Available online 13 December 2014
      Source:The Knee
      Author(s): B. Pierrat , R. Oullion , J. Molimard , L. Navarro , M. Combreas , S. Avril , R. Philippot , P. Calmels
      Background The knee joint is vulnerable to various injuries and degenerative conditions, potentially leading to functional instability. Usual treatments involve knee orthoses to support the joint. However, the level of mechanical action of these devices remains controversial despite high prescription and demand. Methods The mechanical ability of three commercial hinged knee braces and one sleeve to prevent a static drawer was evaluated using a GNRB® arthrometer. The testing of both pathological and healthy joints was performed on 16 patients with documented injuries involving the ACL, and an original method allowed decoupling the contribution of the brace. Results The mean stiffness of the three hinged braces ranged between 2.0 and 7.1N/mm. The most efficient brace was able to exert a restraining force on the joint equivalent to the one exerted by a healthy ACL, up to a 2.8mm anterior displacement of the tibia. For higher anterior displacements, the restraining force of the brace dropped below the level of action of the intact ACL because of the particular non-linear behaviour of this structure. Finally, the most efficient brace was found to vary from subject to subject. Conclusions This study confirmed that fabric-based knee braces may effectively replace the passive mechanical role of the ACL within the low stiffness region of this structure. Although bracing may have other benefits (e.g. proprioception), this shows that they act as an effective passive restraint to low grade anterior laxities. Besides, a high patient-specificity of their effects highlighted the need of personalised objective testing for brace selection.


      PubDate: 2015-02-27T20:12:56Z
       
  • Do counteracting external frontal plane moments alter the intraarticular
           contact force distribution in the loaded human tibiofemoral joint?
    • Abstract: Publication date: Available online 13 December 2014
      Source:The Knee
      Author(s): Karsten Engel , Gert - Peter Brüggemann , Kai Heinrich , Wolfgang Potthast , Christian Liebau
      Background There are strong indications that asymmetric medio–lateral load distribution in the knee joint is a risk factor for osteoarthritis. Externally applied frontal plane moments (adduction and abduction) might affect the distribution of knee joint compartment loading. However, this is not confirmed through intraarticular measurements in loaded human knee joints. The purpose of the study was to determine the force distribution and the movement of the centre of pressure in the loaded tibiofemoral joint as a function of varied externally applied counteracting frontal plane moments and in dependence of the knee flexion angle. Methods Adduction and abduction moments of 2.5Nm and 5Nm were applied to six cadaveric knees exhibiting varus, valgus and normal alignments. The joints were mounted in a knee joint loading simulator. During simulated muscle-driven extension–flexion cycles, intraarticular forces were determined using capacitive pressure sensors inserted into the medial and lateral knee joint compartments. Motion of femur and tibia were assessed by a motion analysis system. Results Externally applied frontal plane moments altered the intraarticular force distribution and caused shifts in the centre of pressure up to 4.3mm in all knee joints. Larger redistribution effects were found in higher knee flexion angles. The medial compartment load increased during the flexion in all investigated knee joints. Conclusions The application of counteracting frontal plane moments for the conservative treatment of osteoarthritis can redistribute the forces and might slow down the progression of the disease. Clinical relevance The findings of this study offer novel insights to guide the development and optimization of mechanical aids for the treatment of osteoarthritic knees.


      PubDate: 2015-02-27T20:12:56Z
       
  • Reducing blood loss in simultaneous bilateral total knee arthroplasty:
           Combined intravenous–intra-articular tranexamic acid administration.
           A prospective randomized controlled trial
    • Abstract: Publication date: Available online 13 December 2014
      Source:The Knee
      Author(s): Fatih Karaaslan , Sinan Karaoğlu , Musa Uğur Mermerkaya , Ali Baktir
      Background We asked whether tranexamic acid (TXA) administration could reduce blood loss and blood transfusion requirements after simultaneous bilateral total knee arthroplasty (TKA). This study examined the role of a novel method of TXA administration in TKA. Methods TXA was administered as a bolus dose of 15mg/kg 10min before the inflation of the tourniquet on the first side. This was followed by intra-articular administration of 3grams at 10min before the deflation of the tourniquet. IV infusion of 10mg/kg/h was continued for 3h following completion on the second side. We measured volume of drained blood 48h postoperatively, decrease in hemoglobin levels 12h postoperatively, amount of blood transfused (BT), and number of patients requiring allogenic BT. Results Median postoperative volume of drained blood was lower in the group receiving TXA (500.00mL) than in control subjects (900.00mL) (p <0.05) [95% CI (−525.00) to (−300.00)]. The median hemoglobin decrease 12 h postoperatively was lower in patients receiving TXA (2.10g/dL) than in control subjects (3.10g/dL) (p<0.05) [95% CI (−1.60) to (−0.60)]. The amount of BT and number of patients requiring BT were lower in patients receiving TXA than in control subjects. Nevertheless, the number of allogeneic units of packed red blood cells transfused in the postoperative period was not significantly higher in the control group than in the TXA group (p=0.109) [95% CI (0.101) to (0.117)]. Conclusions This prospective randomized study showed that during simultaneous bilateral TKA, TXA reduced blood loss with negligible side effects.


      PubDate: 2015-02-27T20:12:56Z
       
  • Minor varus alignment provides better results than neutral alignment in
           medial UKA
    • Abstract: Publication date: Available online 13 December 2014
      Source:The Knee
      Author(s): Michele Vasso , Chiara Del Regno , Antonio D'Amelio , Davide Viggiano , Katia Corona , Alfredo Schiavone Panni
      Introduction Few data exist regarding the outcome and survivorship of medial UKA in patients with minor varus alignment. The purpose of this study was therefore to analyse the clinical results of medial UKA implanted with no more than 7° of varus, and to verify whether there was a relationship between limb alignment and overall outcomes. Material and methods One hundred and twenty five medial fixed-bearing UKAs with no more than 7° of varus were retrospectively analysed. The varus/valgus inclination and thickness of the bone cuts were performed relating to the proximal tibial epiphyseal axis. Patients were assessed with the IKS scores and range of knee motion. The subjects were classified into three groups according to the postoperative femoro-tibial mechanical alignment angle (group A: −2° to 1°; group B: 2° to 4°; group C: 5° to 7°). Results The mean follow-up was 7.6years (range, 3.5–9.3). IKS knee scores increased proportionally with increasing varus according to a linear relationship (p ≪0.01). Additionally, IKS knee scores were significantly higher in group B and still higher in group C if compared to those in group A (p =0.003). Finally, a significantly higher frequency of IKS function scores>90 points in subjects with femoro-tibial mechanical alignment angle≥4° was found (p =0.009). Conclusions Minor varus alignment does not compromise the mid- to long-term outcome of a medial UKA, and gives better results compared to neutral or close-to-neutral alignment. Level of evidence IV — Retrospective case series study.


      PubDate: 2015-02-27T20:12:56Z
       
  • A Comprehensive in vivo Kinematic, Quantitative MRI and Functional
           Evaluation Following ACL Reconstruction – a Comparison between
           Mini-Two Incision and Anteromedial Portal Femoral Tunnel Drilling
    • Abstract: Publication date: Available online 17 December 2014
      Source:The Knee
      Author(s): Drew A. Lansdown , Christina Allen , Musa Zaid , Samuel Wu , Karupppasamy Subburaj , Richard Souza , Brian T. Feeley , Xiaojuan Li , C. Benjamin
      Introduction Multiple techniques are used for femoral tunnel drilling in ACL reconstruction, including the Mini-Two Incision method (MT) and Anteromedial Portal technique (AM). Both techniques allow for independent placement of the femoral tunnel, though there are no reports comparing kinematics and cartilage health after these reconstructions. We hypothesized that both techniques would result in the restoration of normal knee kinematics and show no evidence of early cartilage degeneration. Methods A total of 20 patients were evaluated one year after ACL reconstruction, including 10 patients after MT and 10 patients after AM. MR-imaging was acquired bilaterally with the knee loaded in extension and flexion to evaluate kinematics of the reconstructed knee compared to the normal knee. Quantitative cartilage imaging was obtained and compared to 10 matched control subjects. The Marx Activity Rating Scale and KOOS survey were administered. Results The tibia was positioned significantly more anteriorly in extension and flexion relative to the contralateral knee for the MT group. The tibial position in the AM group was not significantly different from the patient’s contralateral knee. T1ρ values in the central-medial tibia were significantly elevated in the MT group compared to the Control group. KOOS Symptom scores were significantly better for the MT group compared to the AM group. Conclusions We have observed in vivo differences in knee kinematics and early cartilage degeneration between patients following MT and AM ACL reconstruction. Both techniques allow for anatomic ACL reconstruction, though the MT group shows significant early differences compared to the patient’s normal knee.


      PubDate: 2015-02-27T20:12:56Z
       
  • Can two-dimensional measured peak sagittal plane excursions during drop
           vertical jumps help identify three-dimensional measured joint moments?
           
    • Abstract: Publication date: Available online 19 December 2014
      Source:The Knee
      Author(s): Bart Dingenen , Bart Malfait , Jos Vanrenterghem , Mark A. Robinson , Sabine M.P. Verschueren , Filip F. Staes
      Background Less optimal sagittal plane movement patterns are believed to increase knee injury risk in female athletes. To facilitate clinical screening with a user-friendly method, the purpose of the present study was to examine the temporal relationships between two-dimensional measured sagittal plane kinematics and three-dimensional joint moments during the double-leg drop vertical jump (DVJ) and single-leg DVJ (SLDVJ). Methods Fifty injury-free female athletes were tested. Maximal excursions of hip flexion, knee flexion and ankle dorsiflexion were measured through two-dimensional video analysis. Three-dimensional motion and ground reaction forces were recorded to calculate external hip flexion, knee flexion and knee abduction moments during the entire stance phase of DVJ and SLDVJ. One-dimensional statistical parametric mapping was used to examine relationships between peak two-dimensional kinematic variables and three-dimensional moment profiles. Results Hip flexion was significantly related to the hip and knee flexion moment for both tests and knee abduction moment for DVJ during the time frames corresponding with highest three-dimensional moments, while knee flexion was significantly related to the hip flexion moment during these time frames. No significant relationships were found for ankle dorsiflexion with any of the joint moments. Conclusions Two-dimensional measured sagittal plane hip flexion angles at the deepest landing position were associated with peak joint moments of the hip and knee during DVJ and SLDVJ, while the amount of knee flexion was only associated with the hip flexion moment. Assessment of knee injury risk with two-dimensional video analysis could benefit from measuring maximal hip flexion, more so than knee flexion.


      PubDate: 2015-02-27T20:12:56Z
       
  • The reasons for knee arthroplasty revisions are incomparable in the
           different arthroplasty registries
    • Abstract: Publication date: Available online 26 December 2014
      Source:The Knee
      Author(s): Tuukka T. Niinimäki
      Background The arthroplasty registries report the survivorship of knee arthroplasties and the reasons for revisions. The various registries report similar implant survivorships. However, the reasons for the knee revisions have not been compared. The aims of this study were to assess the reasons for knee arthroplasty revisions from the five valid arthroplasty registries and to evaluate whether the reasons for revisions in each registry were similar. Methods The reported reasons for knee arthroplasty revisions were extracted from the arthroplasty registries of Australia, New Zealand, Norway, Sweden, and the National Joint Registry for England and Wales. The relevant data were identified from each arthroplasty registry's annual reports. Results All the arthroplasty registries collected data for each performed knee arthroplasty revision using a specific form. The information provided by the registries varied. The numbers of different variables for the revisions were wide-ranging (from 8–33). In addition to the different variables, the reported percentages between the registries had an extremely wide variation. Conclusion The reasons for knee arthroplasty revisions are categorized differently in various arthroplasty registries, and there is a wide range of percentages presented. The differences in percentages may not be fully explained by the different outcome results in the different countries. The heterogeneity of the registries may guide the recording of the reasons behind the revisions. There is a definite need to standardize the structure of the arthroplasty registries, and to validate the data therein. A larger collaboration between the registries is essential.


      PubDate: 2015-02-27T20:12:56Z
       
  • Is resurfacing the patella cheaper? An economic analysis of evidence
           based medicine on patellar resurfacing
    • Abstract: Publication date: Available online 29 December 2014
      Source:The Knee
      Author(s): Karim A. Meijer , Vinod Dasa
      Background Primary total knee arthroplasty is a high volume procedure which is expected to grow dramatically in the near future. The decision to resurface the patella has been discussed extensively in the literature yet the financial implications of resurfacing versus not resurfacing have not been demonstrated. Methods We identified all randomized controlled trials comparing patellar resurfacing to nonresurfacing in the past ten years and identified the total number of patellofemoral revision surgeries for both resurfaced and nonresurfaced patellas in each study. An expected-value decision tree analysis was created using only data from the randomized controlled trials. Actual costs collected from Medicare reimbursement rates were then applied to the model and a sensitivity analysis was performed. Results The expected value of primary total knee arthroplasty with patellar resurfacing was $13,788.48 while a primary total knee arthroplasty without patellar resurfacing was $14,016.41 after five years. The difference represents an additional $227.92 of Medicare dollars for every primary total knee arthroplasty performed without patellar resurfacing at five years. The model remains valid as long as patellofemoral revision rates after patellar resurfacing remain below 3.54% and patellofemoral revision rates after nonresurfaced patellas remain above 0.77%. Conclusions While initially counterintuitive, resurfacing the patella during a primary total knee arthroplasty is the optimal financial strategy from a Medicare perspective over a mid term period.


      PubDate: 2015-02-27T20:12:56Z
       
  • Effect of body mass index and osteoarthritis on outcomes following
           arthroscopic meniscectomy: A prospective nationwide study
    • Abstract: Publication date: Available online 27 December 2014
      Source:The Knee
      Author(s): O. Bailey , K. Gronkowski , W.J. Leach
      Background Current evidence suggests limiting arthroscopic meniscectomy to those patients with no or early arthritis however outcomes of arthroscopic meniscectomy with patients of a higher body mass index (BMI) are not as widely available. The aim of this study was to determine if patient reported outcome scores for arthroscopic meniscectomy are adversely affected by the degree of knee osteoarthritis or patient BMI. Methods All patients who underwent arthroscopic meniscectomy within the NHS in Scotland between the 6th of February and 29th of April 2012 were audited as part of the Scottish Government Musculoskeletal Audit and were eligible for inclusion within this study. A total of 270 patients returned both their pre-operative and post-operative EuroQol 5Q5D5L descriptive questionnaire and Knee injury and Osteoarthritis Outcomes Scores. Patients were stratified according to BMI, degree of osteoarthritis, history of injury, and duration of knee symptoms. Results Pre-operative to post-operative EuroQol index scores [0.642±0.253 to 0.735±0.277, median±SD] and Knee injury and Osteoarthrtis Outcome Scores [44.63±18.78 to 62.28±24.94, median±SD] improved across all patients (p<0.0001). This was irrespective of degree of BMI, history of injury, or duration of symptoms. There was no such improvement in patients with moderate to severe osteoarthritis. Those patients with a BMI >35kg/m2 had lower post-operative scores than the pre-operative scores of those of BMI <30kg/m2. Conclusions Arthroscopic meniscectomy is beneficial regardless of patient BMI, duration of symptoms, history of injury, or in the presence of early osteoarthritis.


      PubDate: 2015-02-27T20:12:56Z
       
  • Tourniquet versus no tourniquet on knee-extension strength early after
           fast-track total knee arthroplasty; a randomized controlled trial
    • Abstract: Publication date: Available online 31 December 2014
      Source:The Knee
      Author(s): Andreas Harsten , Thomas Bandholm , Henrik Kehlet , Sören Toksvig-Larsen
      Background Thigh tourniquet is commonly used in total knee arthroplasty (TKA) but may contribute to pain and muscle damage. Consequently, the reduction in knee-extension strength after TKA may be caused by quadriceps muscle ischaemia underneath the cuff. Aim To examine if not using a thigh tourniquet during surgery was more effective than using a thigh tourniquet in preserving knee-extension strength 48h after fast-track TKA. Methods A total of 64 patients undergoing TKA were randomized (1:1) to the use of tourniquet (T-group) or no tourniquet (NT-group). In the T-group the tourniquet cuff pressure was based on the patient's systolic pressure and a margin of 100mmHg. It was inflated immediately before surgery and deflated as soon as surgery ended. The primary outcome was the change in knee-extension strength from pre-surgery to 48h after surgery (primary end point). Secondary outcomes were pain, nausea, length of hospital stay (LOS) and periarticular swelling. Results Knee-extension strength 48h after surgery was substantially reduced by about 90% in both groups, with no statistically significant difference between groups (mean difference 1.5N/kg, 95% CI 1.3–1.6). Among the secondary outcomes, the T-group had less bleeding during surgery (56 vs 182mL, P <0.01) compared with the NT-group. There was no difference in postoperative haemoglobin levels, pain, nausea, LOS or periarticular swelling between the groups. Conclusion Not using a thigh tourniquet during surgery was not superior in preserving knee-extension strength at the primary endpoint 48h after fast-track TKA, compared to using a tourniquet.


      PubDate: 2015-02-27T20:12:56Z
       
  • Successful hemicondylar femoral allograft for traumatic bone loss: A
           paediatric case study with ten years of follow-up
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): S. Hornstein , D. Moukoko , F. Deroussen , M.C. Plancq , L.M. Collet , R. Gouron
      The management of massive traumatic defects of the knee joint is challenging, especially in children. Massive osteoarticular allograft may be an option in this kind of traumatic bone loss. We report on the case of a male patient who (at the age of 15) suffered an open grade III condylar femoral joint fracture, with a massive bone defect and a Schatzker V tibial plateau fracture. Ten years after first-line treatment with massive osteoarticular allograft of the lateral femoral condyle, the patient's knee was capable of full extension and 90° flexion. The patient reached a point of being pain free for nine years before he subsequently developed some pain with lateral arthritis progression.


      PubDate: 2015-02-27T20:12:56Z
       
  • Is the smartphone app accurate enough?
    • Abstract: Publication date: Available online 31 December 2014
      Source:The Knee
      Author(s): Giorgio Ferriero , Stefano Vercelli , Francesco Sartorio , Calogero Foti



      PubDate: 2015-02-27T20:12:56Z
       
  • Outcomes of infected revision knee arthroplasty managed by two-stage
           revision in a tertiary referral centre
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): John Stammers , Steven Kahane , Vijai Ranawat , Jonathan Miles , Rob Pollock , Richard W.J. Carrington , Timothy Briggs , John A. Skinner
      Background A two-stage revision remains the gold standard to eradicate deep infection in total knee arthroplasty. Higher failure rates are associated with a number of factors including poly-microbial infections, multiresistant organisms and previous operations. The aims are to investigate [1] the overall success rate of a two-stage revision for infections in TKA, [2] the outcome of repeat two-stage revisions in recurrent infections and [3] the factors affecting the outcomes of such cases. Methods We present the outcomes of a consecutive, retrospective case series of 51 periprosthetic joint infections managed with a two-stage revision knee arthroplasty over a three year period. Results Forty-six (90%) of 51 were referred from other hospitals. Infection was successfully eradicated in 24 (65%) of 37 patients undergoing an initial two-stage procedure. Following a failed two-stage revision, a repeat two-stage revision was performed in 19 patients eradicating infection in 8 (42%). A third two-stage was performed in five of these patients eradicating infection in three with an average follow-up of 43months. Multidrug resistance was present in 69%, and 47% of the patients were infected with multiple organisms. All unsuccessful outcomes involved at least one multidrug-resistant organism compared to 43% in the successful cohort (P =0.0002). Serological markers prior to a second-stage procedure were not significantly different between successful and unsuccessful outcome groups. Conclusion Single or multiple two-stage revisions can eradicate infection despite previous failed attempts. In this series, failure is associated with multidrug resistance, previous failed attempts to eradicate infection and a less favourable host response. Level of evidence IV


      PubDate: 2015-02-27T20:12:56Z
       
  • The risk of sacrificing the PCL in cruciate retaining total knee
           arthroplasty and the relationship to the sagittal inclination of the
           tibial plateau
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Pasquale Sessa , Giulio Fioravanti , Giuseppe Giannicola , Gianluca Cinotti
      Background In cruciate retaining total knee arthroplasty (TKA), a partial avulsion of PCL may occur when en-bloc tibial osteotomy is performed. We evaluated the effects of a tibial cut performed with different degrees of posterior slope on PCL insertion and whether the results are affected by the sagittal inclination of the patient's tibial plateau. Methods We selected 83 MRIs of knees showing mild or no degenerative changes. The effects of a simulated tibial cut performed with a posterior slope of 0°, 3°, 5° and parallel to the patient's tibial plateau inclination on PCL insertion in the proximal tibia were investigated. The results were correlated with the degree of posterior inclination of the tibial plateau. Results Every angle we used for the tibial cut caused a PCL avulsion greater than 50%. The percentage of PCL avulsion significantly increased with increasing the posterior slope of the tibial cut. Patients with sagittal tibial plateau inclination <5° showed greater PCL avulsion than those with sagittal inclination >8°. Conclusions Most of the PCL insertion is likely to be sacrificed when resection of the proximal tibia is performed en-block. The risk of PCL avulsion is reduced in patients showing a marked posterior inclination of the tibial plateau, but even in this group of patients a surgical technique aimed at sparing most of the PCL insertion is necessary.


      PubDate: 2015-02-27T20:12:56Z
       
  • Intra-operative deviation in limb alignment occurring at implantation in
           total knee arthroplasty
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): D.F. Howie , G.J. Love , A.H. Deakin , A.W.G. Kinninmonth
      Background Long-term survival of knee replacement depends on accurate alignment. Despite improvements in cut accuracy mal-alignment of 3° or more is still seen. All methods share common implantation techniques. This study examines the effect of implantation on overall limb alignment relating it to cut alignment and trial alignment. Methods A retrospective review of navigated primary knee replacements was undertaken (n=113). Overall coronal limb alignments for the aggregated cuts, trial and final implanted components were examined. Results All 113 knees had coronal aggregated cut alignment within 2° of neutral (range: 2° varus to 2° valgus). With trial components 99 knees (88%) had an overall coronal limb alignment within 2° of neutral (range: 3° varus to 4° valgus). After final implantation 106 knees (94%) were within 2° of neutral (range: 4° varus to 4° valgus). Forty eight knees (42%) showed no alignment deviation occurring between trial and the final implanted prostheses and 16 knees (14%) shoed a deviation of 2° or more. There was a correlation of both aggregated cut (r=0.284, p=0.002) and trial (r=0.794, p<0.001) with final alignment. There was no significant difference between the final alignment and the aggregated cut alignment(mean difference=−0.15°, p=0.254) or trial alignment (mean difference −0.13°, p=0.155). Conclusions Even when the aggregated alignment produced by the bone cuts is accurate, inaccuracy in final alignment can result from the implantation process. It may be productive for surgeons to concentrate on the implantation process to improve alignment and reduce outliers.


      PubDate: 2015-02-27T20:12:56Z
       
  • Radiostereometric analysis of early anatomical changes following medial
           opening wedge high tibial osteotomy
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Matthew G. Teeter , Kristyn M. Leitch , Dietrich Pape , Xunhua Yuan , Trevor B. Birmingham , J. Robert Giffin
      Background The objective of this study was to use radiostereometric analysis (RSA) to evaluate the anatomical changes that occur in the tibia immediately after surgical correction with medial opening wedge high tibial osteotomy (HTO), and the changes that occur over the course of the first twelveweeks of osseous union. Methods Patients included nine males and one female, with a mean age of 49.0±5.5years and mean BMI of 28.4±3.8kg/m2. The patients underwent HTO using a non-locking plate. RSA marker beads were inserted in the tibia, femur, and patella. RSA exams were first obtained intra-operatively prior to the osteotomy, and subsequently at one, two, four, six, and twelveweeks postoperatively. Results Patients were corrected from a mean alignment preoperatively of 8.6±2.5° to 0.3±1.9° postoperatively, with a mean osteotomy of 12.5±3.6mm. Immediate tibia changes surrounding the osteotomy site included 9.2±2.4° of valgus rotation and 6.2±2.0mm of distal translation. Secondary motions included 2.5±2.4° of internal rotation of the distal tibia, 1.8±1.4mm of posterior movement of the femur, and 8.5±3.4mm of patella baja. Micromotion between the proximal and distal tibial segments decreased over time. Conclusion The results suggest that subtle changes to the anatomy occur, beyond what is intended with the procedure, but partial corrections of these phenomena occurred over the twelveweeks. Micromotion surrounding the osteotomy site decreased with osseous union. Level of evidence Level IV, case series


      PubDate: 2015-02-27T20:12:56Z
       
  • Arthroscopic mosaicplasty: Long-term outcome and joint degeneration
           progression
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Giuseppe Filardo , Elizaveta Kon , Francesco Perdisa , Cecilia Tetta , Alessandro Di Martino , Maurilio Marcacci
      Background This study aims to document the long-term results in a group of patients treated with arthroscopic mosaicplasty for knee cartilage lesions, both in terms of clinical outcome and joint degeneration progression, evaluated by radiographs. Methods 26 patients (19 men and 7 women, mean age 29years, mean BMI 23) treated arthroscopically with mosaicplasty for cartilage defects of the femoral condyles (mean/median/mode size 1.9 standard deviation, SD 0.6cm2) were prospectively evaluated at 12years follow-up. The clinical outcome was analyzed with IKDC and Tegner scores. Range of motion, transpatellar and suprapatellar circumferences were also measured. Radiographs with weight-bearing antero-posterior and Rosenberg projections were used for radiological evaluation in 18 patients, applying both Kellgren–Lawrence score and a direct joint line measurement to assess osteoarthritis. Results A significant improvement in all clinical scores was obtained from the basal evaluation to the 12-year follow-up (IKDC subjective score from 36.8 standard deviation, SD 13.0 to 77.3 standard deviation, SD 20.6, P<0.0005; Tegner score from 2.9 standard deviation, SD 1.3 to 5.2 standard deviation, SD 2.5, P<0.0005), and better results in patients with a higher pre-injury activity level and those requiring fewer plugs. The radiographic evaluation showed significantly poorer Kellgren-Lawrence scores and a reduction of the joint line in the treated compartments. Knees with 3–4 plugs presented a significantly higher joint degeneration level with respect to those implanted with 1–2 plugs. Conclusions Mosaicplasty is an effective surgical option for small lesions of the femoral condyles. Although joint degeneration progression was present at 12years, this did not affect significantly the clinical outcome which was satisfactory at long-term follow-up. Level of evidence IV, case series.


      PubDate: 2015-02-27T20:12:56Z
       
  • Restrained tibial rotation may prevent ACL injury during landing at
           different flexion angles
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Hossein Mokhtarzadeh , Andrew Ng , Chen Hua Yeow , Denny Oetomo , Fatemeh Malekipour , Peter Vee Sin Lee
      Background Internal tibial rotation is a risk factor for anterior cruciate ligament (ACL) injury. The effect of restraining tibial rotation (RTR) to prevent ACL injury during single-leg landing is not well understood. We aimed to investigate the effect of impact load and RTR on ACL injury with respect to flexion angle. We hypothesized that RTR could protect the knee from ACL injury compared to free tibial rotation (FTR) regardless of flexion angle and create a safety zone to protect the ACL. Methods Thirty porcine specimens were potted in a rig manufactured to replicate single-leg landing maneuvers. A mechanical testing machine was used to apply external forces in the direction of the tibial long axis. A 3D displacement sensor measured anterior tibial translation (ATT). The specimens were divided into 3 groups of 10 specimens and tested at flexion angles of 22±1°, 37±1° and 52±1° (five RTR and five FTR) through a consecutive range of actuator displacements until ACL failure. After dissection, damage to the joint was visually recorded. Two-way ANOVA were utilized in order to compare compressive forces, torques and A/P displacements with respect to flexion angle. Results The largest difference between peak axial compressive forces (~3.4 kN) causing ACL injury between RTR and FTR was reported at a flexion angle of 22°. Tibial torques with RTR was in the same range and <20Nm at the instance and just before ACL failure, compared to a significant reduction when cartilage/bone damage (no ACL failure) was reported. Isolated ACL injuries were observed in ten of the 15 FTR specimens. Injuries to bone and cartilage were more common with RTR. Conclusions RTR increases the threshold for ACL injury by elevating the compressive impact load required at lower flexion angles. These findings may contribute to neuromuscular training programs or brace designs used to avoid excessive internal/external tibial rotation. Caution must be exercised as bone/cartilage damage may result.


      PubDate: 2015-02-27T20:12:56Z
       
  • Variations in morphological characteristics of prostheses for total knee
           arthroplasty leading to kinematic differences
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Xiaojun Shi , Zongke Zhou , Bin Shen , Jing Yang , Pengde Kang , Fuxing Pei
      Background and purpose The aim of this study is to compare kinematics during weight-bearing deep knee-bending motion in patients after bilateral total knee arthroplasty (TKA) of two types: 1) a conventional ScorpioFlex prosthesis and 2) a contemporary redesigned non-restrictive-geometry (NRG) prosthesis installed by the same surgeon. Methods We enrolled 15 patients who underwent conventional ScorpioFlex posterior-stabilised TKA in one knee and contemporary NRG TKA on the contralateral side (the same surgeon). During fluoroscopic examination, each patient performed weight-bearing deep knee bending. Motions among all components were analysed using a two- to three-dimensional registration technique. Results The mean maximum flexion was 108° (SD 8) and 120° (SD 9) after ScorpioFlex and NRG TKAs, respectively; there were statistically significant differences between the groups. From extension to maximal flexion, the medial condyle translated by 4.8mm (SD 1.2) and 5.4mm (SD 2.4) posteriorly after ScorpioFlex TKA and NRG TKA, respectively. The lateral femoral condyle moved 8.4mm (SD 1.5) and 12.2mm (SD 2.1) posteriorly after ScorpioFlex TKA and NRG TKA, respectively. There were no significant differences in medial condyle translation between the groups except for the lateral condyle. The total amount of tibial axial rotation during extension to flexion was 5.1° (SD 1.8) after ScorpioFlex and 13.2° (SD 3.4) after NRG TKAs; there were statistically significant differences between the groups. Conclusions NRG resulted in much better maximum flexion, lateral condyle movement and tibial internal rotation than did ScorpioFlex TKAs. The observed kinematic differences are most likely caused by variations in the morphological characteristics of the two implants. Level of evidence Level I, Prospective randomed comparative study.


      PubDate: 2015-02-27T20:12:56Z
       
  • Increased meniscal loading after anterior cruciate ligament transection in
           vivo: A longitudinal study in sheep
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Mohammad Atarod , Cyril B. Frank , Nigel G. Shrive
      Introduction Meniscal injury has been well documented as a frequent consequence of both acute and chronic ACL deficiency. The purpose of this study was to evaluate the effect of ACL deficiency on meniscal loads in vivo and determine how these loads would change over time after ACL injury. Methods The in vivo kinematics of the stifle joint of five sheep were measured during normal gait, as well as 4 and 20weeks after ACL transection. A unique robotic testing platform was then programmed to reproduce all the previously recorded kinematics and the loads carried by medial and lateral menisci during gait were estimated. Results The results demonstrated a significant increase in both medial and lateral meniscal loads 20weeks following ACL transection, mainly during mid-stance phase of gait (p =0.007 and p =0.003, respectively), with interesting inter-subject variability. A moderate correlation (R 2 ≥0.5) between in situ meniscal loads and anterior tibial translations was also detected over time after injury, increased translations post injury generally corresponded to larger meniscal loads. Conclusion The dramatic increase in meniscal loads long term post ACL transection probably explains the meniscal changes or injuries reported clinically in many chronic ACL-deficient knees. Level of evidence: III.


      PubDate: 2015-02-27T20:12:56Z
       
  • The UK Knee Osteotomy Registry (UKKOR)
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): David W. Elson , Matt Dawson , Chris Wilson , Mike Risebury , Adrian Wilson



      PubDate: 2015-02-27T20:12:56Z
       
  • Clinical significance of T2*-weighted gradient-echo MRI to monitor graft
           maturation over one year after anatomic double-bundle anterior cruciate
           ligament reconstruction: A comparative study with proton density-weighted
           MRI
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1
      Author(s): Akihiro Hakozaki , Yasuo Niki , Hiroyuki Enomoto , Yoshiaki Toyama , Yasunori Suda
      Purpose This study examined the feasibility of T2*-weighted imaging (T2*WI) gradient-echo MRI to reflect actual function of the graft after anatomic double-bundle ACL reconstruction. T2*WI and proton density-weighted imaging (PDWI) were compared in the assessment of ACL grafts. Method Sixty-one patients underwent T2*WI and PDWI at 3, 6, and 12 months postoperatively. Signal intensity of the anteromedial bundle (AMB) or posterolateral bundle (PLB) graft standardized to the intensity of the PCL was defined as signal intensity ratio (SIR). Correlations between degree of knee instability and SIR were assessed for each bundle, each time point, and each sequence. The diagnostic efficacy of T2*WI sequence to detect poorly functioning knee with anteroposterior translation ≥4 mm was assessed. Results Significant correlations were observed between SIR and KT values for both AMB and PLB at 12 months on T2*WI (r=0.39 and 0.53, respectively), but not on PDWI. Notably, 9 of 10 patients with poorly functioning graft showing anteroposterior translation ≥4 mm at 12 months formed an isolated group with high T2*WI-SIR. Six of the 10 patients displayed an increase in SIR from 6 to 12 months. Defining anteroposterior translation ≥4 mm at 12 months as the diagnostic standard for poorly functioning graft, increasing T2*WI-SIR offered 60% sensitivity and >90% specificity. Conclusions ACL graft intensity on T2*WI is more strongly associated with actual function of the graft than that on PDWI. An increasing trend in T2*WI-SIR from 6 to 12 months postoperatively represents a possible surrogate indicator for poorly functioning grafts. Level of evidence II


      PubDate: 2015-02-27T20:12:56Z
       
  • A new technique using mesh for extensor reconstruction after proximal
           tibia resection
    • Abstract: Publication date: Available online 10 January 2015
      Source:The Knee
      Author(s): Jiro Ichikawa , Seiichi Matsumoto , Takashi Shimoji , Keisuke Ae , Taisuke Tanizawa , Tabu Gokita
      Background Proximal tibia reconstruction following wide resection in both malignant and benign tumors presents difficulties mainly due to both patellar tendon reconstruction and high risk of infection. The purpose of this study is to determine the efficacy of a new technique using mesh for extensor reconstruction. Methods We retrospectively review nine consecutive patients who underwent resection of proximal tibia with prosthetic reconstruction and reconstruction of extensor using mesh between 2009 and 2012. The surgical technique included the attachment of mesh to the tibial component with a band of meshes looped over the patella and a gastrocnemius flap for coverage. Results One patient had an above-the-knee amputation due to the infection. Eight patients were followed for 33months (range, 20-50) In eight patients, extension lag had a mean of 5°(range 0 to 20). Active flexion had a mean of 96.25 °(range 80 to 120)and ISOLS scores had a mean of 21/30 (range 18 to 26) . All patients were able to ambulate without crutches at the latest follow up. Conclusion Extension lag was significantly less compared to previous reports. No complications were observed in eight patients. Utilization of mesh for extensor reconstruction after proximal tibia resection is a simple, reliable and successful method. Level of Evidence Therapeutic Level IV


      PubDate: 2015-02-27T20:12:56Z
       
  • Contents List
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1




      PubDate: 2015-02-27T20:12:56Z
       
  • Editorial Board
    • Abstract: Publication date: January 2015
      Source:The Knee, Volume 22, Issue 1




      PubDate: 2015-02-27T20:12:56Z
       
  • Rotational Alignment of the Tibial Component Affects the Kinematic
           Rotation of a Weight-Bearing Knee after Total Knee Arthroplasty
    • Abstract: Publication date: Available online 16 January 2015
      Source:The Knee
      Author(s): Hiroyuki Nakahara , Ken Okazaki , Satoshi Hamai , Shinya Kawahara , Hidehiko Higaki , Hideki Mizu-uchi , Yukihide Iwamoto
      Purpose : The purpose of this study is to elucidate how the rotational malalignment of prosthesis after total knee arthroplasty affects the rotational kinematics in a weight-bearing condition. Methods : In this study of 18 knees replaced with the posterior stabilizing fixed-bearing system, which has a relatively low-restricting design, rotational angles between the femoral and tibial components and between the femur and tibia during stair climbing were evaluated in vivo in three dimensions using radiologically based image-matching techniques. Rotational alignments of the components were assessed by postoperative CT. The correlations between the rotational alignments and the rotational angles during stair climbing were evaluated. Results : Rotational alignment of the tibial component significantly correlated with rotational angles between the components as well as between bones during stair climbing. Rotational malalignment of the tibial component toward internal rotation caused a rotational mismatch of the tibial component toward internal rotation relative to the femoral component in 0° extension and caused a rotational mismatch of the tibia (bone) toward external rotation relative to the femur (bone). The knee in which the tibial component was placed close to the AP axis of the tibia did not show any rotational mismatch between either components or bones. Conclusions : Rotational alignment of the tibial component affects the kinematic rotation of the replaced knee during a weight-bearing condition even though using a low-restricting designed surface, and the AP axis can be a reliable reference in determining rotational alignment for the tibial component.


      PubDate: 2015-02-27T20:12:56Z
       
  • Return to Activity among Athletes with a Symptomatic Bipartite Patella: A
           Systematic Review
    • Abstract: Publication date: Available online 17 January 2015
      Source:The Knee
      Author(s): George T. Matic , David C. Flanigan
      Background : A bipartite patella is typically rare, but can become symptomatic during overuse activities such as those performed during athletic events. Therefore, this anomaly typically presents in the young, athletic population, often inhibiting athletic activities. Multiple treatment options exist, with nonsurgical management frequently adopted as the initial treatment of choice. Purpose : To determine the most effective intervention in returning athletes with symptomatic bipartite patella to their prior activity levels. Methods : A systematic review of the literature was performed using PRISMA guidelines to identify studies reporting outcomes of athletes’ ability to return to activity following treatment for a symptomatic bipartite patella. The type of intervention, type of bipartite classification, outcomes, and complications were recorded. Results : Twenty articles with a total of 125 patients and 130 knees were identified and included in this review. A total of 105 athletes made a full return to athletic activity following treatment for their painful bipartite patella. One hundred athletes (85.5%) that underwent surgical treatment were able to make a full return to their sport without symptoms, although this varied by surgical procedure performed. Excision of the painful fragment produced the best results in returning athletes to sport, with 91% returning without symptoms and 9% returning but with residual symptoms. Conclusion : Surgical treatments for symptomatic bipartite patellae are successful at returning athletes to their same level of play, and best outcomes are with excision of the fragment. These results are limited, however, due to the poor quality of original data given the rarity of the anomaly and the underrepresented conservative treatment group.


      PubDate: 2015-02-27T20:12:56Z
       
  • In Vivo Kinematic Effects of Ball and Socket Third Condyle as a Post-cam
           Mechanism in Tri-condylar Knee Implants
    • Abstract: Publication date: Available online 17 January 2015
      Source:The Knee
      Author(s): Shinichiro Nakamura , Adrija Sharma , Kenji Nakamura , Noboru Ikeda , Jun Kawai , Sumesh M. Zingde , Richard D. Komistek
      Background Tri-condylar implants containing a ball and socket third condyle as a post-cam mechanism were developed to accommodate a lifestyle requiring frequent deep flexion activities. The purpose of the current study was to examine the kinematic effects of the ball and socket third condyle during a deep knee bend activity, and to confirm the contact status of the ball and socket joint. Methods Seventeen knees implanted with tri-condylar implants were analyzed using a 3D to 2D registration approach. A distance of less than 1mm denoted ball and socket contact. Medial and lateral contact positions and axial rotation were compared before and after contact. Moreover, the contact position at the third condyle and the center of the ball joint were analyzed. Results After the third condyle contact, posterior translation of the medial and lateral contact positions increased considerably. Meanwhile, the angular rotation remained still. The center of the third condyle did not move after contact, and the contact position at the third condyle remained low. Conclusions The third condyle induced intensive posterior translation of both condyles, and did not prevent axial rotation, which was proved to work properly as a posterior stabilizing post-cam mechanism.


      PubDate: 2015-02-27T20:12:56Z
       
  • Effect of a Single Injection of Tranexamic Acid on Blood Loss after
           Primary Hybrid TKA
    • Abstract: Publication date: Available online 17 January 2015
      Source:The Knee
      Author(s): Yoshinori Ishii , Hideo Noguchi , Junko Sato , Chiduru Tsuchiya , Shin-ichi Toyabe
      Background Control of perioperative blood loss is important in total knee arthroplasty (TKA), especially cementless or hybrid TKA. There is increasing interest in the use of tranexamic acid (TXA) for this purpose; however, studies to date have mainly evaluated the effects of various TXA administration regimens on patients who underwent cemented TKA. We sought to determine (1) whether administration of TXA reduces blood loss after hybrid TKA, and (2) whether an autologous blood reinfusion system is necessary in TKA patients who are treated with TXA. Methods Ninety-five patients (100 knees) who underwent hybrid primary TKA (cemented tibia, uncemented femur) were included in this study. The initial 50 knees were treated without TXA and the following 50 were treated with TXA. Intravenous TXA (1000mg) was administered shortly before deflation of the tourniquet. All continuous variables are expressed as median values. Results Total volumes of blood lost at postoperative 1day were 590ml and 150ml and autotransfusion of collected blood was performed in 88 % and 16% of patients in the without and with TXA groups, respectively. A median volume of 400ml of collected blood was returned to the patients in the without TXA group, and 0ml to the patients in the with TXA group. The calculated volumes of blood lost were 761ml and 683ml (p=0.2250), respectively. Conclusions One intravenous injection of 1000mg TXA may help to control postoperative blood loss and reduce the need for postoperative autologous blood reinfusion after hybrid TKA. Levels of evidence Level II.


      PubDate: 2015-02-27T20:12:56Z
       
  • Effects of perturbation training on knee flexion angle and quadriceps to
           hamstring cocontraction of female athletes with quadriceps dominance
           deficit: Pre–post intervention study
    • Abstract: Publication date: Available online 20 February 2015
      Source:The Knee
      Author(s): Amir Letafatkar , Reza Rajabi , Esmaeil Ebrahimi Tekamejani , Hooman Minoonejad
      Background Knee joint stability through co-contraction (CC) of hamstrings and quadriceps may be necessary for females with Quadriceps Dominance (Q.D) neuromuscular deficit. Unbalanced CC of medial and lateral portion of the knee can predispose women to extended knee position that exaggerate ACL injury. The purpose of this study was to determine the effects of perturbation training on knee flexion angle and neuromuscular characteristics in female athletes with quadriceps dominance deficit. Methods EMG data of quadriceps and hamstrings (during single limb drop-landing), and knee flexion angles (during tuck-jump test) of 29 (14 control and 15 experimental) female athletes with quadriceps dominance deficit were completed at baseline and after sixweeks. Sixweeks of perturbation training in the experimental group was applied over 18 sessions under the supervision of a physiotherapist. Results The VL-LH and VM-MH cocontraction in feed-forward and feedback phases significantly increased after perturbation training. Also peak knee flexion angle significantly increased and reaches from 26.24°±3.54° in pretest to 48.92°±6.18° in posttest due to perturbation training effects on Q.D deficit women (p<0.01). Conclusions Finally because the Q.D neuromuscular deficit is one of the important mechanisms of noncontact ACL injuries in female athletes and the effect of perturbation training in solving this problem indicated in this study, so the use of perturbation trainings is recommended to women athlete coaches to eliminate this defect and improve athletic performance (functional tuck jump test). Clinical relevance The balanced cocontraction ratios produced after the perturbation training may benefit in anterior cruciate ligament injury-prevention.


      PubDate: 2015-02-27T20:12:56Z
       
  • Cartilage health in high tibial osteotomy using dGEMRIC: Relationships
           with joint kinematics
    • Abstract: Publication date: Available online 21 February 2015
      Source:The Knee
      Author(s): Agnes G. d'Entremont , Robert G. McCormack , Kenard Agbanlog , Simon G.D. Horlick , Trevor B. Stone , Mojieb M. Manzary , David R. Wilson
      Purpose The aims of this study are to determine how opening-wedge high tibial osteotomy (HTO) affects cartilage health in the tibiofemoral (TF) joint and patella, and to explore relationships between TF and patellofemoral (PF) joint kinematics and cartilage health in HTO. Methods 14 knees (13 subjects) with medial TF osteoarthritis (OA) were examined before HTO and 6 and 12months after HTO using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) to evaluate cartilage health at the TF joint and patella. They were also examined using a validated 3D MR knee kinematics measurement to obtain 11 rotations and translations at both TF and PF joints. Results No statistically significant differences in overall TF or patellar dGEMRIC score were found at 6 or 12months after HTO. However three subjects had large decreases (mean 105ms) in TF dGEMRIC at 6months that recovered at 12months. Kinematics for these subjects were compared to subjects who did not have decreases in TF dGEMRIC at 6months (n =5). Differences were observed between groups with HTO in anterior and proximal tibial translation (mean differences 3.05mm and 1.35mm), and patellar flexion (mean difference 3.65°). These changes were consistent between 6 and 12months, despite recovery of TF dGEMRIC values. Conclusions We did not find significant differences in TF or patellar dGEMRIC before and after HTO with all subjects, however there were differences in kinematics between subjects who had a decrease in TF dGEMRIC at 6months and those who did not. This suggests a link between joint kinematics and cartilage health in HTO. Clinical relevance The effect of opening-wedge high tibial osteotomy on cartilage GAG concentration may be linked to specific changes in knee kinematics following surgery


      PubDate: 2015-02-27T20:12:56Z
       
  • How accurate are orthopedic surgeons in diagnosing periprosthetic joint
           infection after total knee arthroplasty?: A multicenter study
    • Abstract: Publication date: Available online 24 February 2015
      Source:The Knee
      Author(s): In Jun Koh , Woo-Shin Cho , Nam Yong Choi , Javad Parvizi , Tae Kyun Kim
      Background The lack of standardized diagnostic criteria for periprosthetic joint infection (PJI) poses a challenge to accurate diagnosis of PJI. Recently, the Musculoskeletal Infection Society (MSIS) proposed diagnostic criteria for PJI. However, it is not known how well these proposed criteria accommodate real clinical scenarios. We determined what proportion of patients satisfied the MSIS criteria, and if MSIS criteria were not met, what other rationales were used to diagnose PJI. Methods We retrospectively reviewed the records of 303 patients who underwent two-stage exchange arthroplasty for treatment of PJI of the knee at 17 institutions. The rationale for making the diagnosis of PJI was also recorded, if the case did not meet the MSIS criteria. In addition, detailed information about isolated microorganisms were gathered. Results Among the 303 patients, 198 met the diagnostic criteria proposed by MSIS. Among the 105 patients who did not meet the MSIS criteria, 88% met two or three minor criteria; however joint fluid analysis or histologic analysis was not performed in 85% of these 105 patients. The most common rationale for the diagnosis of PJI was the presence of abnormal physical findings. Microorganisms were identified in only 52% of all patients; the most common organism was coagulase-negative Staphylococcus. Conclusions The diagnosis of PJI was based on clinical suspicion in approximately one-third of cases. In this series, joint aspiration or histological analysis was not performed in a large number of patients. Thus, surgeons should perform joint fluid and histologic analysis to assure the accuracy of PJI diagnosis.


      PubDate: 2015-02-27T20:12:56Z
       
  • Combination of Eccentric Exercise and Neuromuscular Electrical Stimulation
           to Improve Quadriceps Function Post-ACL Reconstruction
    • Abstract: Publication date: Available online 10 December 2014
      Source:The Knee
      Author(s): Lindsey K. Lepley , Edward M. Wojtys , Riann M. Palmieri-Smith
      Background Neuromuscular electrical stimulation (NMES) has been shown to reduce quadriceps activation failure (QAF), and eccentric exercise has been shown lessen muscle atrophy post-ACL reconstruction. Given that these are two critical components of quadriceps strength, intervention combining these therapies may be effective at reinstituting quadriceps function post-anterior cruciate ligament (ACL) reconstruction. Objectives To evaluate the effectiveness of a combined NMES and eccentric exercise intervention to improve the recovery of quadriceps activation and strength post-reconstruction. Design Parallel longitudinal design. Setting Laboratory. Participants Thirty-six individuals post-injury were placed into four treatment groups (N&E, NMES and eccentrics; E-only, eccentrics only; N-only, NMES-only; STND, standard of care) and ten healthy controls participated. Intervention N&E and N-only received the NMES protocol 2x per week for the first six weeks post-reconstruction. N&E and E-only received the eccentric exercise protocol 2x per week beginning six weeks post-reconstruction. Main outcome measure Quadriceps activation was assessed via the superimposed burst technique and quantified via the central activation ratio. Quadriceps strength was assessed via maximal voluntary isomeric contractions (Nm/kg). Data was gathered on three occasions: pre-operative, 12-weeks-post-surgery and at return-to-play. Results No differences in pre-operative measures existed (P>0.05). E-only recovered quadriceps activation better than N-only or STND (P<0.05). N&E and E-only recovered strength better than N-only or the STND (P<0.05) and had strength values that were similar to healthy individuals at return-to-play (P>0.05). Conclusion Eccentric exercise was capable of restoring levels of quadriceps activation and strength that were similar to those of healthy adults and better than NMES alone.


      PubDate: 2015-02-27T20:12:56Z
       
  • One-step cartilage repair in the knee: Collagen-covered microfracture and
           autologous bone marrow concentrate. A pilot study
    • Abstract: Publication date: Available online 20 November 2014
      Source:The Knee
      Author(s): D. Enea , S. Cecconi , S. Calcagno , A. Busilacchi , S. Manzotti , A. Gigante
      Background Different single-stage surgical approaches are currently under evaluation to repair cartilage focal lesions. To date, only little is known on even short-term clinical follow-up and almost no knowledge exists on histological results of such treatments. The present paper aims to analyze the clinical and histological results of the collagen-covered microfracture and bone marrow concentrate (C-CMBMC) technique in the treatment of focal condylar lesions of knee articular cartilage. Methods Nine patients with focal lesions of the condylar articular cartilage were consecutively treated with arthroscopic microfractures (MFX) covered with a collagen membrane immersed in autologous bone marrow concentrate (BMC) from the iliac crest. Patients were retrospectively assessed using several standardized outcome assessment tools and MRI scans. Four patients consented to undergo second look arthroscopy and biopsy harvest. Results Every patient was arthroscopically treated for a focal condylar lesion (mean area 2.5 SD(0.4) cm2). All the patients (mean age 43 SD(9) years) but one experienced a significant clinical improvement from the pre-operative condition to the latest follow-up (mean 29 SD(11) months). Cartilage macroscopic assessment at 12months revealed that all the repairs appeared almost normal. Histological analysis showed a hyaline-like cartilage repair in one lesion, a fibrocartilaginous repair in two lesions and a mixture of both in one lesion. Conclusions The first clinical experience with single-stage C-CMBMC for focal cartilage defects in the knee suggests that it is safe, it improves the short-term knee function and that it has the potential to recreate hyaline-like cartilage. Level of evidence IV, case series


      PubDate: 2014-12-16T05:31:31Z
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2015