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Journal Cover The Knee
  [SJR: 1.236]   [H-I: 53]   [12 followers]  Follow
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0968-0160
   Published by Elsevier Homepage  [3175 journals]
  • Anterior cruciate ligament ruptures in German elite soccer players:
           Epidemiology, mechanisms, and return to play
    • Authors: Erik Schiffner; David Latz; Jan P. Grassmann; Alberto Schek; Simon Thelen; Joachim Windolf; Johannes Schneppendahl; Pascal Jungbluth
      Pages: 219 - 225
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Erik Schiffner, David Latz, Jan P. Grassmann, Alberto Schek, Simon Thelen, Joachim Windolf, Johannes Schneppendahl, Pascal Jungbluth
      Background Anterior cruciate ligament ruptures (ACLRs) are severe sports-related injuries with significant consequences for affected players and teams. This study aims to identify the epidemiology and injury-related lay-off after ACLR in professional male soccer players from the first-division German Bundesliga. Methods Exposure times and incidence of anterior cruciate ligament ruptures were collected during 7.5 consecutive seasons using two media-based registers. Results A total of 72 total ACLRs were registered in 66 different players with an incidence of 0.040 per 1000h of exposure (95% CI 0.009–0.12). On average there were 9.6 ACLRs per season and 0.53 per team and season. The mean age of players affected was 24 (standard deviation±3.6) years. The number of ACLRs recorded per season fluctuated during the period observed. Goalkeepers are significantly (P <0.05) less prone to suffer an ACLR compared to outfield players. Conclusions Understanding ACLR loading mechanisms, knowing risk factors for the injury and mean off time after ACLR are essential information for the coach, the medical staff, the elite soccer players, the insurance and team managers. Our results are in accordance with reports based on information from medical team staff. Therefore, our analysis of ACLR based on media sources may serve as an alternative for injury reports in elite soccer. The information of this study may be helpful for the medical staff taking care of professional soccer players and for orthopedic surgeons performing ACL reconstructions in this patient population.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.010
  • Curve analyses reveal altered knee, hip, and trunk kinematics during
           drop–jumps long after anterior cruciate ligament rupture
    • Authors: Kim Hébert-Losier; Lina Schelin; Eva Tengman; Andrew Strong; Charlotte K. Häger
      Pages: 226 - 239
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Kim Hébert-Losier, Lina Schelin, Eva Tengman, Andrew Strong, Charlotte K. Häger
      Background Anterior cruciate ligament (ACL) ruptures may lead to knee dysfunctions later in life. Single-leg tasks are often evaluated, but bilateral movements may also be compromised. Our aim was to use curve analyses to examine double-leg drop–jump kinematics in ACL-reconstructed, ACL-deficient, and healthy-knee cohorts. Methods Subjects with unilateral ACL ruptures treated more than two decades ago (17–28years) conservatively with physiotherapy (ACLPT, n=26) or in combination with reconstructive surgery (ACLR, n=28) and healthy-knee controls (n=25) performed 40-cm drop–jumps. Three-dimensional knee, hip, and trunk kinematics were analyzed during Rebound, Flight, and Landing phases. Curves were time-normalized and compared between groups (injured and non-injured legs of ACLPT and ACLR vs. non-dominant and dominant legs of controls) and within groups (between legs) using functional analysis of variance methods. Results Compared to controls, ACL groups exhibited less knee and hip flexion on both legs during Rebound and greater knee external rotation on their injured leg at the start of Rebound and Landing. ACLR also showed less trunk flexion during Rebound. Between-leg differences were observed in ACLR only, with the injured leg more internally rotated at the hip. Overall, kinematic curves were similar between ACLR and ACLPT. However, compared to controls, deviations spanned a greater proportion of the drop–jump movement at the hip in ACLR and at the knee in ACLPT. Conclusions Trunk and bilateral leg kinematics during double-leg drop–jumps are still compromised long after ACL-rupture care, independent of treatment. Curve analyses indicate the presence of distinct compensatory mechanisms in ACLPT and ACLR compared to controls.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.12.005
  • The role of the patellar tendon angle and patellar flexion angle in the
           interpretation of sagittal plane kinematics of the knee after knee
           arthroplasty: A modelling analysis
    • Authors: B.H. van Duren; H. Pandit; P. Pechon; A. Hart; D.W. Murray
      Pages: 240 - 248
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): B.H. van Duren, H. Pandit, P. Pechon, A. Hart, D.W. Murray
      Background Many different measures have been used to describe knee kinematics. This study investigated the changes of two measures, the patellar tendon angle and the patellar flexion angle, in response to variations in the geometry of the knee due to surgical technique or implant design. Methods A mathematical model was developed to calculate the equilibrium position of the extensor mechanism for a particular tibiofemoral position. Calculating the position of the extensor mechanism allowed for the determination of the patellar tendon angle and patellar flexion angle relationships to the knee flexion angle. The model was used to investigate the effect of anterior–posterior position of the femur, change in joint line, patellar thickness (overstuffing, understuffing), and patellar tendon length; these parameters were varied to determine the effect on the patellar tendon angle/knee flexion angle and patellar flexion angle/knee flexion angle relationships. Results The patellar tendon angle was a good indicator of anterior–posterior femoral position and change in patellar thickness, and the patellar flexion angle a good indicator of change in joint line, and patellar tendon length. Conclusions The patellar tendon angle/knee flexion angle relationship was found to be an effective means of identifying abnormal kinematics post-knee arthroplasty. However, the use of both the patellar tendon angle and patellar flexion angle together provided a more informative overview of the sagittal plane kinematics of the knee.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.006
  • Baseline varus deformity is associated with increased joint loading and
           pain of non-operated knee two years after unilateral total knee
    • Authors: Du Hyun Ro; Hyuk-soo Han; Seong Hwan Kim; Yoon-Ho Kwak; Jae-Young Park; Myung Chul Lee
      Pages: 249 - 255
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Du Hyun Ro, Hyuk-soo Han, Seong Hwan Kim, Yoon-Ho Kwak, Jae-Young Park, Myung Chul Lee
      Background The goals of this study were (1) to document the gait pattern of patients with unilateral knee osteoarthritis (OA), (2) to determine the knee adduction moment (KAM) changes in the non-operated knee, and (3) to identify the predictors of change in KAM in the non-operated knee. Methods The study recruited 23 patients with advanced unilateral knee OA. The preoperative Kellgren–Lawrence (KL) grade of the non-operated knee was one or two; non-operated knee pain, rated using a numeric rating scale (NRS), was less than three out of 10 points. We used a commercial gait analysis system to evaluate kinetics and kinematics. Radiological and gait measurements at the two-year follow-up were compared with baseline data. Results The preoperative asymmetrical gait cycle characterized by elongation of the stance phase of the non-operated knee became symmetrical after TKA. The average KAM of the non-operated knee increased (P =0.010) and it was best predicted by the baseline mechanical axis of the non-operated knee. If the baseline mechanical axis was varus four degrees or above (varus group), the average KAM increased by 0.64 (% body weight×height, P =0.015), while for varus less than four degrees (non-varus group), KAM was unchanged. The KL grade was increased in the varus group (P =0.020) but it was unchanged in the non-varus group. Average pain NRS score was also higher (P =0.044) in the varus group. Conclusions Close follow-up is necessary for patients with a baseline varus deformity of the non-operated knee because of the higher possibility of developing pain, subsequent arthritis and increased joint loading of the non-operated knee. Level of evidence III, retrospective cohort study.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.013
  • Comparative postural stability in patients with lateral meniscus versus
           medial meniscus tears
    • Authors: Jin-Hyuck Lee; Jae-Won Heo; Dae-Hee Lee
      Pages: 256 - 261
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Jin-Hyuck Lee, Jae-Won Heo, Dae-Hee Lee
      Background Types of mechanoreceptors may differ between the medial and lateral menisci, suggesting that postural stability may differ between patients with medial and lateral meniscus tears. However, to date, postural stability has not been compared in patients with medial and lateral meniscus tears. This study used stabilometry to compare postural stability in patients with medial and lateral meniscus tears. Methods Postural stability and thigh muscle strength were assessed in 24 patients with medial and 18 patients with lateral meniscus tears. Postural stability was determined by measuring the anteroposterior (APSI), mediolateral (MLSI), and overall (OSI) stability indices using stabilometry. Maximal torque (60°/s) of the quadriceps and hamstring was evaluated using an isokinetic testing device. Results The three stability indices, OSI, APSI, and MLSI, in both involved and uninvolved knees were all significantly greater in patients with lateral than with medial meniscus tears. (P <0.001 for all OSI, APSI, and MLSI in both involved and uninvolved knees, except for P =0.005 for MLSI of involved knees). In patients with medial meniscus tears, both OSI (1.4±0.4 vs. 1.1±0.4, P =0.037) and MLSI (0.9±0.3 vs. 0.8±0.3, P =0.041) were significantly higher on the injured than the uninjured side. In patients with lateral meniscus tears, none of the stability indices differed significantly between injured and uninjured knee joints. Conclusion Postural stability of both the injured and uninjured knee joints was poorer in patients with lateral than with medial meniscus tears.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.012
  • Dynamic tracking influenced by anatomy following medial patellofemoral
           ligament reconstruction: Computational simulation
    • Authors: John J. Elias; Kerwyn C. Jones; S. Cyrus Rezvanifar; Joseph N. Gabra; Melanie A. Morscher; Andrew J. Cosgarea
      Pages: 262 - 270
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): John J. Elias, Kerwyn C. Jones, S. Cyrus Rezvanifar, Joseph N. Gabra, Melanie A. Morscher, Andrew J. Cosgarea
      Background Continued patellar instability can occur following medial patellofemoral ligament (MPFL) reconstruction. Computational simulation of function was used to investigate the influence of the lateral position of the tibial tuberosity, trochlear dysplasia and patella alta on lateral patellar tracking following MPFL reconstruction. Methods Multibody dynamic simulation models were developed to represent nine knees being treated for recurrent patellar instability. Knee extension against gravity and dual limb squatting were simulated with and without simulated MPFL reconstruction. Graft resting lengths were set to allow 10mm and five millimeters of patellar lateral translation at 30° of knee flexion. The bisect offset index, lateral tibial tuberosity to posterior cruciate ligament tibial attachment (TT–PCL) distance, lateral trochlear inclination, and Caton–Deschamps index were quantified at every five degrees of knee flexion to characterize lateral tracking, lateral position of the tibial tuberosity, trochlear dysplasia, and patella alta, respectively. For the pre-operative and post-operative conditions and each type of motion, bisect offset index was correlated with the anatomical parameters using stepwise multivariate linear regression. Results For both motions, the pre-operative and post-operative bisect offset indices were significantly correlated with lateral trochlear inclination and lateral TT–PCL distance. For both motions, the adjusted r2 decreased with MPFL reconstruction, but was still approximately 0.5 for MPFL reconstruction allowing five millimeters of lateral translation. Conclusion MPFL reconstruction decreases but does not eliminate lateral maltracking related to trochlear dysplasia and a lateralized tibial tuberosity. Patients with these pathologies are likely at the highest risk for instability related to maltracking following MPFL reconstruction.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.002
  • Ultrasound evaluation of infrapatellar fat pad impingement: An exploratory
           prospective study
    • Authors: Himabindu Mikkilineni; Patricia B. Delzell; Jack Andrish; Jennifer Bullen; Nancy A. Obuchowski; Naveen Subhas; Joshua M. Polster; Jean P. Schils
      Pages: 279 - 285
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Himabindu Mikkilineni, Patricia B. Delzell, Jack Andrish, Jennifer Bullen, Nancy A. Obuchowski, Naveen Subhas, Joshua M. Polster, Jean P. Schils
      Background We sought to determine whether there are ultrasound parameters that differ between knees with symptomatic fat pad synovial impingement and asymptomatic knees. Methods A prospective study was performed in patients with clinical signs and symptoms of fat pad synovial impingement and asymptomatic controls. Eleven symptomatic knees and 10 asymptomatic controls were evaluated. Ultrasound imaging was performed before and after exercise. Evaluated parameters included largest fat lobule compressibility, subjective assessment of vascularity, largest vessel diameter, and subjective assessment of dynamic fat pad motion during flexion and extension. Receiver operating characteristic (ROC) curve analysis was used to assess whether changes in these parameters were different between symptomatic and asymptomatic knees. Results Change in the largest vessel diameter was greater and trended toward dilation in asymptomatic knees compared to symptomatic knees (mean: 0.83 vs. −0.02; P <0.001). No significant differences were observed between symptomatic and asymptomatic knees with respect to pre-exercise versus post-exercise states in subjective assessment of vascularity (P =0.131), fat pad motion (P =0.115), or percent change of the largest fat lobule (P =0.241). However, overall compressibility of the fat pad lobule was significantly diminished in the pre-exercise state in symptomatic knees compared to asymptomatic controls. Conclusions This study demonstrated a statistically significant change in the largest vessel diameter from pre- to post-exercise states between symptomatic and asymptomatic knees, as well as abnormal pre-exercise fat lobule compressibility in symptomatic knees. These findings show promise that with further research, ultrasound could have clinical utility in diagnosing infrapatellar fat pad impingement.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.008
  • A preliminary modeling investigation into the safe correction zone for
           high tibial osteotomy
    • Authors: Jennifer LB Martay; Antony JR Palmer; Neil K Bangerter; Stuart Clare; A Paul Monk; Cameron P Brown; Andrew J Price
      Pages: 286 - 295
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Jennifer LB Martay, Antony JR Palmer, Neil K Bangerter, Stuart Clare, A Paul Monk, Cameron P Brown, Andrew J Price
      Background High tibial osteotomy (HTO) re-aligns the weight-bearing axis (WBA) of the lower limb. The surgery reduces medial load (reducing pain and slowing progression of cartilage damage) while avoiding overloading the lateral compartment. The optimal correction has not been established. This study investigated how different WBA re-alignments affected load distribution in the knee, to consider the optimal post-surgery re-alignment. Methods We collected motion analysis and seven Tesla MRI data from three healthy subjects, and combined this data to create sets of subject-specific finite element models (total=45 models). Each set of models simulated a range of potential post-HTO knee re-alignments. We shifted the WBA from its native alignment to between 40% and 80% medial–lateral tibial width (corresponding to 2.8°–3.1° varus and 8.5°–9.3° valgus), in three percent increments. We then compared stress/pressure distributions in the models. Results Correcting the WBA to 50% tibial width (0° varus–valgus) approximately halved medial compartment stresses, with minimal changes to lateral stress levels, but provided little margin for error in undercorrection. Correcting the WBA to a more commonly-used 62%–65% tibial width (3.4°–4.6° valgus) further reduced medial stresses but introduced the danger of damaging lateral compartment tissues. To balance optimal loading environment with that of the historical risk of under-correction, we propose a new target: WBA correction to 55% tibial width (1.7°–1.9° valgus), which anatomically represented the apex of the lateral tibial spine. Conclusions Finite element models can successfully simulate a variety of HTO re-alignments. Correcting the WBA to 55% tibial width (1.7°–1.9° valgus) optimally distributes medial and lateral stresses/pressures.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.12.006
  • Time between anterior cruciate ligament injury and reconstruction and
           cartilage metabolism six-months following reconstruction
    • Authors: Hope C. Davis; Jeffery T. Spang; Richard F. Loeser; Staffan Larsson; Veronica Ulici; J. Troy Blackburn; R. Alexander Creighton; Ganesh M. Kamath; Joanne M. Jordan; Stephen W. Marshall; Brian Pietrosimone
      Pages: 296 - 305
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Hope C. Davis, Jeffery T. Spang, Richard F. Loeser, Staffan Larsson, Veronica Ulici, J. Troy Blackburn, R. Alexander Creighton, Ganesh M. Kamath, Joanne M. Jordan, Stephen W. Marshall, Brian Pietrosimone
      Background To determine the association between time from injury to ACL reconstruction (TimeInjury–ACLR) and biochemical markers of cartilage metabolism and inflammation six months following ACL reconstruction (ACLR). Methods Individuals with a unilateral ACL injury were enrolled at initial presentation in the orthopedic clinic; blood was collected six months following ACLR. Enzyme-linked immunosorbent assays were used to analyze the ratio of serum concentrations of type-II collagen breakdown (C2C) to synthesis (CPII), plasma matrix metalloproteinase-3 (MMP-3), interleukin-6 (IL-6), and serum aggrecan neoepitope (ARGS). We used separate linear regressions to assess associations between biochemical markers and TimeInjury–ACLR. Results Twenty-two participants (50% females, mean [SD], age 21.9 [4.5] years old; BMI 23.8 [2.6] kg/m2) completed the study. TimeInjury–ACLR ranged from nine to 67days (31.0 [14.4days]). Greater TimeInjury–ACLR predicted greater serum C2C:CPII ratios six months following ACLR (C2C:CPII=0.15 [0.02], R2 =0.213, P=0.030). Males (R2 =0.733, P=0.001) but not females (R2 =0.030, P=0.609) demonstrated a significant association between greater C2C:CPII and TimeInjury–ACLR at the six-month follow-up exam. TimeInjury–ACLR did not associate with IL-6, MMP-3, or ARGS at six months. Conclusions Greater time between injury and ACL reconstruction was associated with greater serum C2C:CPII six months following ACLR in males but not females, and IL-6, MMP-3, and ARGS levels were not associated with TimeInjury–ACLR in males or females. The time between ACL injury and ACLR may affect collagen metabolism in males and should be further investigated in a larger study along with other patient-relevant outcomes.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.009
  • Tourniquet time in total knee arthroplasty
    • Authors: Lasse E. Rasmussen; Henriette A. Holm; Per W. Kristensen; Per Kjaersgaard-Andersen
      Pages: 306 - 313
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Lasse E. Rasmussen, Henriette A. Holm, Per W. Kristensen, Per Kjaersgaard-Andersen
      Background Whether the arterial tourniquet in total knee arthroplasty (TKA) is a friend or a foe is still debated. Longer ischemia causes hypoxic damage; yet short duration of a tourniquet may influence outcome. Understanding the time-dependent influence of the tourniquet in TKA patients could improve the overall outcome and safety. The purpose of the study was to measure the tourniquet-induced time-dependent alterations in skeletal muscle metabolism in TKA to establish a ‘safe tourniquet time.’ Methods In the femoral quadriceps muscle of 12 patients undergoing a total knee arthroplasty with a tourniquet (TKA) we measured the ischemic response using microdialysis. Lactate, pyruvate, glucose and glycerol were measured in the muscle underneath the tourniquet, in the ischemic muscle distally to the tourniquet and in the opposite muscle as a reference. Results Lactate pyruvate ratio (L/P ratio) increased time-dependently after 15min of ischemia. L/P ratio increased faster underneath the tourniquet compared to ischemic tissue distal to the tourniquet. Glycerol was elevated underneath the tourniquet compared to ischemic tissue distal to the tourniquet and correlated to the individual ischemic response. Only minor increases in creatine-kinase, asparagine-aminotransferase, and lactate-dehydrogenase were observed. Thirty minutes of reperfusion normalized lactate levels. Conclusions The muscle underneath the tourniquet suffered more from ischemia than the ischemic tissue distal to the tourniquet. Less than 15min of ischemia did not increase ischemic markers. If any muscle damage occurs from longer tourniquet time, it is likely reversible and occurs mainly underneath the tourniquet. Fifteen minutes of ischemia appears safe.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.002
  • Unexplained pain following total knee arthroplasty: Is rotational
           malalignment the problem'
    • Authors: Simon W. Young; Mustafa Saffi; Mark J. Spangehl; Henry D. Clarke
      Pages: 329 - 334
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Simon W. Young, Mustafa Saffi, Mark J. Spangehl, Henry D. Clarke
      Background Malrotation of tibial and femoral components is a potential source of pain following total knee arthroplasty (TKA). This study aimed to 1) compare component rotation in TKA patients with unexplained pain versus a control group with well-functioning TKAs and 2) investigate the relationship between TKA component rotation and pain. Methods Seventy one patients with unexplained pain after primary TKA were compared to a control cohort of 41 well functioning TKA patients. Both groups underwent post-operative computed tomography (CT) scans to assess component rotation. Findings were compared between the painful and control TKA groups. Results We found no difference in femoral component rotation between the painful and control groups (mean 0.6° vs 1.0° external rotation (ER), p=0.4), and no difference in tibial component rotation (mean 11.2° vs 9.5° internal rotation (IR), p=0.3). Also, there was no difference in combined mal-rotation (tibial+femoral rotation) between the groups (mean 10.5° vs 8.5°IR, p=0.25). Fifty-nine percent of patients in the painful group had tibial component rotation >9°IR vs 49% in the control group. Conclusion In the largest study yet on component rotation after TKA, we found no difference in the incidence of tibial, femoral, or combined component mal-rotation in painful versus well-functioning TKAs. Tibial component IR relative to the junction of the medial to middle thirds of the tibial tubercle appears to be common in patients with well-functioning TKAs. The significance of slight tibial IR should be interpreted with caution when evaluating the painful TKA. Level III retrospective case–control study.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.011
  • Interactive effect of femoral posterior condylar offset and tibial
           posterior slope on knee flexion in posterior cruciate
           ligament-substituting total knee arthroplasty
    • Authors: Hyuk-Soo Han; Seung-Baik Kang
      Pages: 335 - 340
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Hyuk-Soo Han, Seung-Baik Kang
      Background This work aimed to evaluate the changes in the femoral posterior condylar offset (PCO) and tibial slope after posterior cruciate ligament (PCL)-substituting total knee arthroplasty (TKA), and to address the presence of any interactive effect between the two on knee flexion. Methods Fifty-two PCL-substituting TKAs were performed using a posterior referencing system. Three-dimensional reconstructed computed tomographic (CT) images were used to evaluate PCO and tibial slope before and after arthroplasty. Range of motion and clinical scores were evaluated at a mean of 3.1years postoperatively. Multivariate linear model with interaction terms was used to evaluate and compare the relationships among changes in PCO, tibial slope, and postoperative knee flexion angles. Results The degree of change in PCO was greater in the lateral condyle than in the medial condyle (3.1±2.5mm and −0.5±2.8mm, respectively). Postoperative medial and lateral tibial slopes were 1.4°±1.8 and 1.4°±2.0, respectively. The mean degree of postoperative knee flexion was 125°. Analysis with interaction terms and covariate adjustment demonstrated that medial PCO and tibial slope were significantly related to knee flexion with interactive effect (P =0.011). In cases with <3° posterior tibial slope, the postoperative PCO was positively correlated to the degree of knee flexion angle. However, in cases with >3° tibial slope, PCO was negatively correlated to knee flexion. Conclusion Medial femoral PCO and tibial slope showed interactive effect on knee flexion after PCL-substituting TKAs. Reconstitution of the proper PCO and avoiding excessive tibial slope may be necessary.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.001
  • Polyethylene liner dislocation of fixed-bearing medial oxinium
           unicompartmental arthroplasty with severe metallosis
    • Authors: Nicholas Greco; Keith Berend
      Pages: 341 - 345
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Nicholas Greco, Keith Berend
      The case of an atraumatic dislocation of a fixed bearing in a medial unicompartmental arthroplasty with an oxinium femoral component is presented. A review of the literature pertaining to knee arthroplasty locking mechanisms is discussed. Potential modes of locking mechanisms failure are reviewed including the recognition of such failures in the clinical setting. This is the first report of a dislocated fixed-bearing medial oxinium unicompartmental arthroplasty and consequent metal arthrogram.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.004
  • Letter to Editor “Optimizing the dose of local infiltration analgesia
           and gabapentin for total knee arthroplasty, a randomized single blind
           trial in 128 patients”
    • Authors: Mark C. Kendall; Lucas J. Castro Alves
      Pages: 346 - 347
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Mark C. Kendall, Lucas J. Castro Alves

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.013
  • Reply to Kendall et al.
    • Authors: Maurik H.M. van Haagen; Hennie Verburg; Brechtje Hesseling; Lauri Coors; Nick T. van Dasselaar; Pim N.J. Langendijk; Nina M.C. Mathijssen
      Pages: 348 - 349
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Maurik H.M. van Haagen, Hennie Verburg, Brechtje Hesseling, Lauri Coors, Nick T. van Dasselaar, Pim N.J. Langendijk, Nina M.C. Mathijssen

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.009
  • Editorial
    • Authors: Caroline B. Hing; Oday Al-Dadah
      First page: 1
      Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2
      Author(s): Oday Al-Dadah, Caroline Hing

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.005
  • Editorial
    • Authors: Caroline B. Hing; Oday Al-Dadah
      First page: 1
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Caroline B. Hing, Oday Al-Dadah

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.01.005
  • Differences between sexes in the standard and advanced dimensioning of
           lateral meniscal allografts
    • Authors: Patrycja Mickiewicz; Michał Walczak; Michał Łaszczyca; Damian Kusz; Zygmunt Wróbel
      Pages: 8 - 14
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Patrycja Mickiewicz, Michał Walczak, Michał Łaszczyca, Damian Kusz, Zygmunt Wróbel
      Background There are many different methods of meniscal allograft measurements, which depend on individual tissue bank procedures. Due to the lack of a standardised method of dimensioning, measurement results may vary between individual cases. Consequently, allograft may be mismatched to the patient's knee anatomy. The purpose of this study was to measure four meniscal dimensions – two standard and two specific – and then compare them between sexes. Methods Fourteen cadaveric lateral menisci (seven male and seven female) were scanned using a microtomography scanner. The obtained three-dimensional (3-D) models of each meniscus were analysed, taking into account four dimensions: circumference, width, central meniscal concavity, and total meniscal volume. The computer researcher was not informed of the original data of the meniscal samples until the calculations were completed. Results No statistical between-sex differences were found in the standard dimensions. The specific dimensions, in turn, presented statistically significant between-sex differences (P >0.05). The mean difference between male and female total volume of the meniscus was equal to 36.59%, and the mean difference between male and female central meniscal concavity surface was equal to 31.22%. Conclusion This study found that sex should be taken into account as an important factor during a matching procedure performed by tissue bank staff.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.11.002
  • Usefulness of the “grand-piano sign” for determining femoral
           rotational alignment in total knee arthroplasty
    • Authors: Takaaki Ohmori; Tamon Kabata; Yoshitomo Kajino; Tadashi Taga; Daisuke Inoue; Takashi Yamamoto; Tomoharu Takagi; Junya Yoshitani; Takuro Ueno; Hiroyuki Tsuchiya
      Pages: 15 - 24
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Takaaki Ohmori, Tamon Kabata, Yoshitomo Kajino, Tadashi Taga, Daisuke Inoue, Takashi Yamamoto, Tomoharu Takagi, Junya Yoshitani, Takuro Ueno, Hiroyuki Tsuchiya
      Background The “grand-piano sign” is a well-known indicator of proper rotational femoral alignment. We investigated changes in the shape of the femoral anterior cutting plane by changing the rotational alignment, anterior portion depth, and cutting plane flexion angle. Methods We simulated various cutting planes after cutting the anterior portion of the femur next to the distal femoral osteotomy in 50 patients with varus knee and also a femoral anterior osteotomy with four degree (S group) and seven degree (T group) flexion angles regarding the mechanical axis. We defined the final cutting plane as the farthest position that we could reach without making a notch and the precutting plane as two millimeters anterior from the final cutting plane. The simulated resection plane was rotated to produce external and internal rotation angles of 0°, three degrees, and five degrees relative to the surgical transepicondylar axis (SEA). We investigated medial and lateral portions of the femoral anterior cutting plane length ratio (M/L). Results When we cut parallel to SEA, M/L was 0.67±0.09 and 0.62±0.12 in the T and S groups, respectively. M/L was approximately 0.8 and 0.5 with five degree internal and external rotations, respectively (P <0.01). On comparing final cutting and precutting planes, there were no significant differences in M/L without five degree external rotation in the T group and no significant difference in any case in the S group (P >0.01). Conclusions The ideal M/L of the femoral anterior cutting plane was 0.62–0.67. M/L did not change with a precutting plane in almost all rotational patterns.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.11.008
  • Neuromuscular adaptations in older males and females with knee
           osteoarthritis during weight-bearing force control
    • Authors: Heather J. Bigham; Teresa E. Flaxman; Andrew J.J. Smith; Daniel L. Benoit
      Pages: 40 - 50
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Heather J. Bigham, Teresa E. Flaxman, Andrew J.J. Smith, Daniel L. Benoit
      Background Females exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA. Objective To identify sex-related differences in OA-affected adults and within-sex differences between healthy and OA-affected adults' muscular activation patterns during lower limb loading. Methods Thirty adults with OA and 36 controls completed a standing ground reaction force (GRF) matching protocol requiring participants to expose equal body weight to each leg and modulate horizontal GRFs while maintaining constant joint positions. Electromyography was plotted as a function of GRF direction to depict muscle activation patterns. Muscles were classified as a general joint stabilizer, specific joint stabilizer or moment actuator by quantifying activation patterns with a test of asymmetry, specificity index and mean direction of activity. Lower limb kinematics and kinetics were also recorded. Results In general, muscle roles as it relates to joint stability did not differ between groups. Compared to controls, both males and females with OA demonstrated greater rectus femoris activity and reduced knee rotation moments. Females with OA had significantly greater biceps femoris and gastrocnemius activity during respective lateral, and anterior–medial loading directions compared to males with OA. Conclusions We identified fundamental differences in muscular stabilization strategies in older adults with OA as well as sex-related changes in neuromuscular function that may influence joint loading conditions and provide insight into the greater incidence of knee OA in females.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.06.004
  • Does different duration of non-operative immobilization have an effect on
           the redislocation rate of primary patellar dislocation' A
           retrospective multicenter cohort study
    • Authors: Bo Kaewkongnok; Anders Bøvling; Nikolaj Milandt; Celia Møllenborg; Bjarke Viberg; Lars Blønd
      Pages: 51 - 58
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Bo Kaewkongnok, Anders Bøvling, Nikolaj Milandt, Celia Møllenborg, Bjarke Viberg, Lars Blønd
      Background Immobilization devices such as plaster splints, casts and braces have been used for first time patellar dislocation (FTPD) in order to prevent redislocation. This study evaluates different non-operative immobilization regimes upon rates of redislocation. Methods A retrospective cohort study with a study population of 1366 in which 601 subjects under 30years with FTPD were included from three hospitals. Exclusion criteria were osteochondral fracture, ligament injury and subluxation. Subjects were divided into five groups; unknown/none, two weeks of brace, two weeks of brace followed by bandage, four weeks of brace and six weeks of brace with increasing of range of motion. Radiographs were evaluated for trochlear dysplasia (TD), patella alta, trochlear depth and growth zone. Crude analysis and logistic regression adjusted for radiographic assessments, age, gender and rehabilitation was done in STATA® with significance p≤0.05. Results Forty-five point eight percent were between 15 and 19years and 51.4% were male. One hundred sixty-three experienced redislocation (27.1%). Logistic regression was performed at 404 subjects and showed that rehabilitation, gender, TD, patella alta, and growth zone had no significant odds ratio (OR) on redislocation. The duration of brace demonstrated no significant OR in reducing redislocation. Subjects between 20 and 29years showed lower OR in redislocation (95% CI) of 0.27 (0.11; 0.64, p=0.003). Conclusion This study demonstrated no difference in duration of brace treatment in reducing patella redislocation after FTPD. Rehabilitation and predisposal factors such as TD, trochlear depth, patella alta and open growth zone did not influence the redislocation rate. Increasing age reduced risk of redislocation.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.10.002
  • Smartphone-based accelerometry is a valid tool for measuring dynamic
           changes in knee extension range of motion
    • Authors: Morten Pallisgaard Støve; Thorvaldur Skuli Palsson; Rogerio Pessoto Hirata
      Pages: 66 - 72
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Morten Pallisgaard Støve, Thorvaldur Skuli Palsson, Rogerio Pessoto Hirata
      Introduction Measurement of static joint range of motion is used extensively in orthopaedic and rehabilitative communities to benchmark treatment efficacy. Static measures are, however, insufficient in providing detailed information about patient impairments. Dynamic range of motion measures could provide more detailed information about patient impairments thus leading to better clinical assessments. Reliable and valid methods are available, but due to limitations in the present technology, dynamic measures are seldom performed in clinical settings. The objective of this study was to determine the validity of smartphone-based accelerometry measuring the dynamic range of motion of the knee joint during a passively executed extension movement. Materials and methods Dynamic knee extension range of motion was examined three consecutive times in twenty-one healthy male subjects utilising an isokinetic dynamometer to generate passively the extension motion. Measurements of joint angles in dynamic knee extension were performed using two methods: (i) isokinetic dynamometer (gold-standard method, Biodex System 4 Pro) and (ii) smartphone (iPhone 6, attached to the tibia) accelerometry data. Results Tests of validity showed excellent correlation (rs=0.899) between methods, with a low standard error of measurement of 0.62deg. and limits of agreement ranging from −9.1 to 8.8deg. Interclass correlation coefficients showed excellent between-measures reliability (ICC>0.862) for both methods. Conclusions Smartphone-based accelerometry is a valid tool for measuring the range of motion at the knee joint during dynamic extension movements. This method enables the clinician to carry out simple, low cost, and valid clinical measurements of dynamic knee extension range of motion.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.11.001
  • Influence of knee flexion angle and transverse drill angle on creation of
           femoral tunnels in double-bundle anterior cruciate ligament reconstruction
           using the transportal technique: Three-dimensional computed tomography
           simulation analysis
    • Authors: Chong Hyuk Choi; Sung-Jae Kim; Yong-Min Chun; Sung-Hwan Kim; Su-Keon Lee; Nam-Kyu Eom; Min Jung
      Pages: 99 - 108
      Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1
      Author(s): Chong Hyuk Choi, Sung-Jae Kim, Yong-Min Chun, Sung-Hwan Kim, Su-Keon Lee, Nam-Kyu Eom, Min Jung
      Background The purpose of this study was to find appropriate flexion angle and transverse drill angle for optimal femoral tunnels of anteromedial (AM) bundle and posterolateral (PL) bundle in double-bundle ACL reconstruction using transportal technique. Methods Thirty three-dimensional knee models were reconstructed. Knee flexion angles were altered from 100° to 130° at intervals of 10°. Maximum transverse drill angle (MTA), MTA minus 10° and 20° were set up. Twelve different tunnels were determined by four flexion angles and three transverse drill angles for each bundle. Tunnel length, wall breakage, inter-tunnel communication and graft-bending angle were assessed. Results Mean tunnel length of AM bundle was >30mm at 120° and 130° of flexion in all transverse drill angles. Mean tunnel length of PL bundle was >30mm during every condition. There were ≥1 cases of wall breakage except at 120° and 130° of flexion with MTA for AM bundle. There was no case of wall breakage for PL bundle. Considering inter-tunnel gap of >2mm without communication and obtuse graft-bending angle, 120° of flexion and MTA could be recommended as optimal condition for femoral tunnels of AM and PL bundles. Conclusion Flexion angle and transverse drill angle had combined effect on femoral tunnel in double-bundle ACL reconstruction using transportal technique. Achieving flexion angle of 120° and transverse drill angle close to the medial femoral condyle could be recommended as optimal condition for femoral tunnels of AM and PL bundles to avoid insufficient tunnel length, wall breakage, inter-tunnel communication and acute graft-bending angle.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2017.09.005
  • The anterolateral ligament is a distinct ligamentous structure: A
           histological explanation
    • Authors: Thomas Neri; Pierre Dalcol; Fabien Palpacuer; Florian Bergandi; Jean Michel Prades; Frederic Farizon; Remi Philippot; Michel Peoc'h
      Abstract: Publication date: Available online 11 April 2018
      Source:The Knee
      Author(s): Thomas Neri, Pierre Dalcol, Fabien Palpacuer, Florian Bergandi, Jean Michel Prades, Frederic Farizon, Remi Philippot, Michel Peoc'h
      Background The aim was to determine whether the anterolateral ligament (ALL) had a histological structure that defined it as a real ligament. Methods Histological examination of 30 ALL samples taken from fresh-frozen knees were performed. The ALL femoral insertion and its relationship with the lateral collateral ligament (LCL) were studied and the tibial insertion and its relationship with articular cartilage of the tibial joint surface were analyzed. For the ligamentous part, its histological structure and its differences with the articular capsule were studied. Results This connective tissue is composed of a dense fibrous core constituted by a network of oriented collagenous fibers. The periphery of this dense connective center is made up of loose fibrocollagenous tissue with vascular structures and focal deposits of adipose tissue. This part was in contact but different to the joint capsule. With a perpendicular orientation of the collagen fibers relative to the bone, a fibrocartilaginous zone with an unmineralized hyalinized aspect, a mineralization front, its bone insertions presented a typical ligamentous insertion. With a cleavage plane between ALL and LCL femoral insertion, the ALL appeared to have a femoral insertion distinct from the LCL. ALL tibial insertion was less characteristic with less organized connective tissue and was at a distance from the articular cartilage. Conclusion From its bony insertion to its tissue composition and organization, the ALL has all the histological characteristics of a ligamentous structure. Our study confirms that ALL can be considered a real and distinct ligament.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.03.012
  • In vivo heterotopic culturing of prefabricated tendon grafts with
           mechanical stimulation in a sheep model
    • Authors: M. Petri; P. Lu; M. Omar; M. Ettinger; C. Krettek; C. Neunaber; M. Jagodzinski
      Abstract: Publication date: Available online 11 April 2018
      Source:The Knee
      Author(s): M. Petri, P. Lu, M. Omar, M. Ettinger, C. Krettek, C. Neunaber, M. Jagodzinski
      Background The goal of this study is to investigate the biomechanical and histological properties of in vivo heterotopically prefabricated cruciate ligament replacement grafts with and without mechanical stimulation. The clinical goal is to heterotopically prefabricate a bone–tendon–bone graft for anterior cruciate ligament reconstruction, which allows rapid ingrowth and early full weight bearing. Methods In a sheep model, eight quadriceps tendon grafts were harvested and introduced into culture chambers at their proximal and distal ends. In group S, four tendon-chamber constructs were mechanically stimulated by direct attachment to the quadriceps tendon and patella. In group NS, the same constructs were cultured without proximal attachment. All sheep were sacrificed six weeks postoperatively and the constructs were examined biomechanically and histologically. The healthy contralateral ACL and quadriceps tendon were used as controls. Results Macroscopically, no obvious ossification could be observed at the ends of the tendon-chamber constructs six weeks postoperatively. Histologically, the tendon tissue from the mechanically stimulated constructs revealed higher counts of cells and capillaries. However, there was less regular cell distribution and collagen fiber orientation compared to the control group. In addition, osteoblasts and osteogenesis were observed in the prefabricated constructs both with and without mechanical stimulation. Biomechanically, there were no significant differences in stiffness, elongation and ultimate failure load between the groups. Conclusion In vivo heterotopic culture of prefabricated tendon grafts may have the potential to stimulate osteoblasts and induce osteogenesis. Future studies with longer follow-up and modifications of the surgical technique and culture conditions are desirable.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.006
  • Association between increase in vertical ground reaction force loading
           rate and pain level in women with patellofemoral pain after a
           patellofemoral joint loading protocol
    • Authors: Ronaldo Valdir Briani; Marcella Ferraz Pazzinatto; Marina Cabral Waiteman; Danilo de Oliveira Silva; Fábio Mícolis de Azevedo
      Abstract: Publication date: Available online 11 April 2018
      Source:The Knee
      Author(s): Ronaldo Valdir Briani, Marcella Ferraz Pazzinatto, Marina Cabral Waiteman, Danilo de Oliveira Silva, Fábio Mícolis de Azevedo
      Background The etiology of patellofemoral pain (PFP) is thought to be the result of increased patellofemoral joint (PFJ) load and aberrant lower extremity mechanics, including altered vertical ground reaction forces (VGRF). However, few studies have investigated the association between an increase in pain and VGRF loading rates in the context of PFP. Thus, this study aimed to investigate the immediate effects of PFJ loading on pain and VGRF loading rate, and to see if there is a link between modification of both pain and VGRF loading rate during stair negotiation. Methods Thirty-four women with PFP underwent VGRF analysis during stair negotiation under two conditions: with (condition 2) and without (condition 1) being previously submitted to a PFJ loading protocol in order to or not to exacerbate their knee pain, respectively. Results The VGRF loading rates were significantly higher in condition 2 (Mean ± standard deviation (SD)=4.0±0.6N/s) compared to condition 1 (Mean±SD=3.6±0.5N/s) during stair ascent and during stair descent (Mean±SD: condition 1=6.3±1.1N/s; condition 2=7.0±1.4N/s). In addition, VGRF loading rates were higher during stair descent compared to stair ascent in both conditions. There were significant correlations between the increase in pain and VGRF loading rate during both tasks. Conclusion There seemed to be an important relation between the increase in pain and VGRF loading rates in women with PFP. Based on these findings, interventions aimed at reducing VGRF loading rates are important in the context of PFP.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.03.009
  • Taurine protects against knee osteoarthritis development in experimental
           rat models
    • Authors: Yiqun Bian; Meng Zhang; Kai Wang
      Abstract: Publication date: Available online 9 April 2018
      Source:The Knee
      Author(s): Yiqun Bian, Meng Zhang, Kai Wang
      Background Osteoarthritis (OA) is one of the complex diseases that affect a large population of the world. The aim of the current study was to explore the roles of taurine in OA rat models, and discover the related mechanisms. Methods OA rat models were established by anterior cruciate ligament transection (ACLT) plus medial meniscus resection (MMx) surgery on the right knees. Secondary mechanical allodynia, weight-bearing alterations and knee joint width were evaluated before surgery and every two weeks after surgery. At 14weeks, histopathological analysis was conducted on the knee joint cartilage. Protein amount of MMP-3 and CHOP was evaluated by western blot. Results Taurine injection after surgery significantly relieved the symptoms of OA in rat models in a dose-dependent and time-dependent manner, as shown by alleviation of secondary mechanical allodynia, decrease in hind limb weight-bearing alterations, and inhibited knee swelling. Moreover, histopathological analysis showed that taurine inhibited matrix loss and cartilage degeneration in a dose-dependent manner. Taurine administration strikingly suppressed the expression of matrix metalloproteinase-3 (MMP-3) and CHOP. Conclusion These results indicated that taurine administration exhibited protective effects by inhibiting MMP-3 and CHOP expression, and subsequently alleviated the OA symptoms in experimental rat models.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.03.004
  • A bigger suture diameter for anterior cruciate ligament all-inside graft
           link preparation leads to better graft stability: An anatomical specimen
    • Authors: Thomas M. Tiefenboeck; Lena Hirtler; Markus Winnisch; Julian Joestl; Thomas Koch; Micha Komjati; Marcus Hofbauer; Roman C. Ostermann
      Abstract: Publication date: Available online 6 April 2018
      Source:The Knee
      Author(s): Thomas M. Tiefenboeck, Lena Hirtler, Markus Winnisch, Julian Joestl, Thomas Koch, Micha Komjati, Marcus Hofbauer, Roman C. Ostermann
      Background In anterior cruciate ligament reconstruction, different suture types are used for graft link preparation. Thus the aim of this study was to determine whether differences in the diameter of the suture used influence biomechanical stability of the prepared graft. We hypothesized that the use of a greater suture diameter leads to a higher load to failure rate in tested graft links. Methods In an anatomic specimen study, ligament preparation was enrolled in 15 cadaveric knees. The material used was the semitendinosus/gracilis tendon, which was fresh frozen (−80°) after harvesting for four weeks. The grafts were then defrosted, randomized into two groups and prepared with the same technique: 12 with a suture; FiberWire No. 2 and 12 with a FiberWire No. 0. Results Overall, the group using FiberWire No. 2 presented with a mean load to failure rate of 730.67N, mean overall final elongation of the graft was 5.98mm. In the FiberWire No. 0 group mean load to failure was with a mean overall elongation of the graft of 6.96mm. Significant differences (P =0.006) between the two groups with regard to the load to failure rate were found, with FiberWire No. 2 withstanding forces better. There was no difference in elongation of the grafts or mode to failure between the two groups. Conclusions Graft preparation with a bigger suture type is recommended to gain better load to failure rates, also in smaller-diameter grafts. Regarding the elongation rate, different suture types did not influence the outcome. Level of evidence Anatomical specimen study, Level III.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.03.010
  • Reliability evaluation of inter-eminence line, Akagi and Dalury lines for
           intraoperative tibial rotation: An osteology-based study
    • Authors: Rhodri Williams; Amal Thomas; Stefan Bajada; Tony Antonios; Rhidian Morgan-Jones; Jelena Bekvalac; Philip Adds
      Abstract: Publication date: Available online 20 March 2018
      Source:The Knee
      Author(s): Rhodri Williams, Amal Thomas, Stefan Bajada, Tony Antonios, Rhidian Morgan-Jones, Jelena Bekvalac, Philip Adds
      Background This large osteology study examined the reliability, reproducibility and correlation between previously described tibial tray rotation alignment lines (including Akagi and Dalury lines). In addition, it described a novel inter-eminence line utilising the tibial plateau inter-condylar eminences as a landmark. Methods A total of 214 post-medieval (18–19th centuries) skeletal tibia were examined. The inter/intra-observer variation and correlation between reference lines were measured. Results Inter-observer reproducibility was excellent and there were no differences between Akagi, Dalury, and inter-eminence lines. Similarly, intra-observer reliability was excellent for Akagi, Dalury, and inter-eminence lines. Qualitative review of tibial inter-condylar eminences suggested that these could be easily identifiable. When taking the medial angle from a medial–lateral reference line, the Akagi line showed a mean of 96.90° (±10.27), inter-eminence line 94.52° (±12.84), and Dalury line 88.06° (±11.75). The angle produced by the Dalury line was significantly different from both the Akagi and inter-eminence lines (P ≤0.001). The Akagi line and inter-eminence line showed a strong correlation (r =0.74). The Dalury line showed a weaker correlation with both the Akagi line (r =0.69) and inter-eminence line (r =0.40). Conclusion This study suggested that tibial rotation lines showed excellent intra/inter-observer reliability and reproducibility. The novel and easily drawn inter-eminence line showed strong correlation with the Akagi line and could be used for tibial tray rotational alignment in total knee arthroplasty.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.010
  • Influence of stem length on component flexion and posterior condylar
           offset in revision total knee arthroplasty
    • Authors: Max Ettinger; Peter Savov; Omar Balubaid; Henning Windhagen; Tilman Calliess
      Abstract: Publication date: Available online 19 March 2018
      Source:The Knee
      Author(s): Max Ettinger, Peter Savov, Omar Balubaid, Henning Windhagen, Tilman Calliess
      Background Hyperextension of the femoral component and excessive slope of the tibial component may delay the cam–post engagement in semi-constrained revision total knee arthroplasty (TKA). Further, it may compromise the posterior condylar offset (PCO). No prior study has determined whether a short 50-mm stem, or longer stems (100mm and 150mm) lead to less hyperextension of the femoral component or excessive slope and its influence on the posterior condylar offset. Methods Flexion/extension of the femoral component with respect to the sagittal femoral anatomic axis of the distal diaphysis (SFAA) and the tibial slope were measured from rotationally controlled lateral X-rays of 126 consecutive patients with a one- or two-stage revision TKA. Stems of 50mm, 100mm and 150mm were analyzed. Further, reconstruction of the PCO with respect to stem length and component flexion was evaluated. Results The average flexion (+) or extension (−) of the femoral component in the sagittal distal anatomical axis was −4.1°±2.8° (mean ± std) for components, which have been implanted with 50-mm stems and 1.1°±1.1° for components with 100- or 150-mm stems, respectively (P =0.0001). The average slope of the tibial was 2.6°±1.5° for tibial trays with 50-mm stems, which was more than the 1.3°±1° for trays with 100-mm stems (P =0.0001). The average PCO ratio was 0.8±1.7 for femoral components with 50-mm stems, which was less than the 1.0±1.7 for trays with 100-mm stems (P =0.0001). Conclusions Because 50-mm stems resulted in about three degree hyperextension of the femoral component with respect to the SFAA compared to 100-mm or 150-mm stems, the longer stems do not alter the natural femoral flexion and a delay of the cam–post engagement may be avoided. Further, a better reconstruction of the PCO may be archived with the use of longer stems.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.011
  • Femoral component rotation in patellofemoral joint replacement
    • Authors: Hans-Peter W. van Jonbergen; Robin E. Westerbeek
      Abstract: Publication date: Available online 16 March 2018
      Source:The Knee
      Author(s): Hans-Peter W. van Jonbergen, Robin E. Westerbeek
      Background Clinical outcomes in patellofemoral joint replacement may be related to femoral component rotation. Assessment of rotational alignment is however difficult as patients with isolated patellofemoral osteoarthritis often have trochlear dysplasia. The use of the medial malleolus as a landmark to guide rotation has been suggested. The purpose of our study was to evaluate this technique with regard to femoral component rotation, and to correlate rotation with clinical outcomes at one-year follow-up. Methods Forty-one knees in 39 patients had patellofemoral joint replacement using the Zimmer Gender-Solutions patellofemoral prosthesis. Intraoperatively, we determined femoral component rotational alignment using an extramedullary rod aimed at the inferior tip of the medial malleolus. Postoperatively, we measured the angle between the femoral component and the anatomical transepicondylar axis using CT. The amount of rotation was correlated with clinical outcomes at one-year follow-up. Results Forty knees in 38 patients were available for one-year follow-up. Mean femoral component rotation relative to the anatomical transepicondylar axis was 1.4° external rotation (range, −3.8 to 5.7°). We found no statistically significant correlation between femoral component rotation and change from baseline KOOS subscales at one-year follow-up. Conclusions Our findings show that when using the medial malleolus as a landmark to guide rotation, the femoral component of the patellofemoral prosthesis was oriented in external rotation relative to the anatomical transepicondylar axis in 80% of knees. Our study did not show a relation between the amount of external rotation and clinical outcomes. Level of evidence Level III.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.007
  • Instrumented gait analysis in patients with medial osteoarthritis of the
           knee after mobile-bearing unicompartmental knee arthroplasty
    • Authors: J.B. Seeger; J.P. Schikschneit; C. Schuld; R. Rupp; M. Rickert; A. Jahnke; G.S. Maier; M. Clarius
      Abstract: Publication date: Available online 16 March 2018
      Source:The Knee
      Author(s): J.B. Seeger, J.P. Schikschneit, C. Schuld, R. Rupp, M. Rickert, A. Jahnke, G.S. Maier, M. Clarius
      Background Unicompartmental knee arthroplasty (UKA) is an effective treatment for patients with medial osteoarthritis of the knee joint. Instrumented gait analysis provides an objective measure to quantify and qualify postoperative changes of gait. The purpose of this study was to evaluate standardized instrumented gait analysis for functional recovery and gait as an outcome of mobile-bearing UKA in patients with medial osteoarthritis of the knee. Methods Twenty-one patients with isolated medial osteoarthritis of the knee joint received mobile-bearing UKA. They were examined by a gait analysis before surgery and after an average follow-up time of seven months. Gait analysis was performed on a treadmill with six infrared-cameras to identify changes of gait characteristics (e.g., velocity, stride time, stride length, knee adduction and hip abduction). Results Mean velocity (chosen by individuals) increased from 0.61 to 0.76m/s and further significant advancements, particularly in the knee adduction and the hip abduction were detected. Time and length of strides improved significantly as well as the clinical scores American Knee Society Score (AKSS), Oxford-12, Hannover Functional Ability Questionnaire for Osteoarthritis (FFbH-OA) Score and Devane Score. Conclusion Mobile-bearing UKA can restore physiological axis of the leg and improve gait and function of the knee joint. The combination of instrumented gait analysis with clinical scores constitutes an eligible measuring instrument to quantify and qualify changes in patients' gait patterns.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.014
  • Magnetic resonance imaging of the posterior cruciate ligament in flexion
    • Authors: William Craddock; Troy Smithers; Craig Harris; William du Moulin; Robert Molnar
      Abstract: Publication date: Available online 14 March 2018
      Source:The Knee
      Author(s): William Craddock, Troy Smithers, Craig Harris, William du Moulin, Robert Molnar
      Background Posterior cruciate ligament (PCL) injuries of the knee are common and sometimes difficult to diagnose. Magnetic resonance imaging (MRI), performed using standard orthogonal plane views, is the investigation of choice. It can be particularly difficult to differentiate acute partial and complete tears and identify elongation of chronic healed tears. The aim of the paper is to describe a new method of positioning the patient with the knee flexed at 90°, allowing the PCL to be visualised in a position of greatest length and tension which may assist in differentiating and identifying these injuries. Methods Four symptomatic patients with suspected PCL injuries, two acute and two chronic, were MRI scanned using a routine protocol with the knee in extension before performing oblique sagittal fast spin-echo (FSE) proton-density (PD) sequences with the knee positioned in 90° of flexion. The appearance of the PCLs were then qualitatively assessed. Results MRI scanning with the knee in flexion identified more extensive PCL injury than standard imaging. In the two patients with acute injuries, partial tears on the standard orthogonal plane views were found to be complete ruptures. In the two patients with chronic injuries, elongation of the PCL not identifiable on the standard orthogonal plane views was apparent. Conclusion MRI scanning of the PCL with the knee flexed at 90° may help in differentiating partial and complete ruptures of the PCL and identifying elongation of the PCL in chronic injuries.

      PubDate: 2018-04-15T19:19:04Z
      DOI: 10.1016/j.knee.2018.02.003
  • Content List
    • Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2

      PubDate: 2018-04-15T19:19:04Z
  • British Association for Surgery of the Knee (Diary of Events)
    • Abstract: Publication date: March 2018
      Source:The Knee, Volume 25, Issue 2

      PubDate: 2018-04-15T19:19:04Z
  • Contents List
    • Abstract: Publication date: January 2018
      Source:The Knee, Volume 25, Issue 1

      PubDate: 2018-04-15T19:19:04Z
  • Exploring individual adaptations to an anterior cruciate ligament injury
           prevention programme
    • Authors: Aaron S. Fox; Jason Bonacci; Scott G. McLean; Natalie Saunders
      Abstract: Publication date: Available online 9 January 2018
      Source:The Knee
      Author(s): Aaron S. Fox, Jason Bonacci, Scott G. McLean, Natalie Saunders
      Background Individual responses to anterior cruciate ligament injury prevention programmes (ACL IPPs) have received little attention. This study examined the effects of an ACL IPP on neuromuscular control and lower limb biomechanics during landing at the group and individual levels. Methods Sixteen female athletes were randomly allocated to training (n =8) or control (n =8) groups. Electromyography, and three-dimensional kinematic and kinetic data were collected during landing at two testing sessions. Repeated measures ANOVA and effect sizes (Cohen's d) examined the effect of the IPP at the group and individual levels. A sub-group analysis comparing the effect of the IPP on ‘high-’ (i.e. large peak knee abduction moment at baseline) versus ‘low-risk’ individuals was also conducted. Results At the group level; the IPP increased activation of the medial hamstrings prior to landing (p<0.001; d =0.264) and the medial gastrocnemius at landing (p<0.001; d =0.426), and increased hip external rotation early after initial contact (p<0.001; d =0.476). Variable adaptations were seen across individuals within the training group for all variables (p<0.001). The IPP had a large effect in reducing frontal plane knee moments for ‘high-risk’ individuals (d >0.91), however these results did not reach statistical significance (p>0.05). Conclusions The IPP induced adaptations during landing, however, individual data revealed dissimilar responses to the programme. Individuals displaying a pre-existing high-risk strategy may incur greater benefits from IPPs, yet only if the programme targets the relevant high-risk strategy.

      PubDate: 2018-01-09T19:18:37Z
      DOI: 10.1016/j.knee.2017.11.011
  • Synthetic mesh vs. allograft extensor mechanism reconstruction in total
           knee arthroplasty — A systematic review of the literature and
    • Authors: David Shau; Ryan Patton; Suhag Patel; Laura Ward; George Guild
      Abstract: Publication date: Available online 8 January 2018
      Source:The Knee
      Author(s): David Shau, Ryan Patton, Suhag Patel, Laura Ward, George Guild
      Background: Extensor mechanism disruption after total knee arthroplasty (TKA) is a devastating complication. Reconstruction with allograft and synthetic mesh has been described. However, these reports have typically been small case series, and controversy exists with regard to which reconstruction technique is optimal. Methods: The authors performed a systematic review using PUBMED, MEDLINE, EMBASE, BIOSIS,, and Cochrane Database of Systematic Reviews identifying 14 articles meeting inclusion criteria and producing 204 knees for comparison. Studies with repairs performed under full knee extension were included. Case reports and non-English studies were excluded. Available demographics and clinical outcome data were collected from each study. Appropriate statistical analysis was performed to compare the variables. Results: Baseline demographics and patient complexity were similar between the two cohorts. Reconstruction success rates (76% allograft vs. 74% mesh), average time to diagnosis/treatment, Knee Society Scores (KSS), knee range of motion/extensor lag, and complication rates yielded no statistical difference. Synthetic mesh was used more frequently with concomitant revision of components. Discussion: This systematic review shows equivalent success of allograft and synthetic mesh with approximately 25% failure rate in both groups. Periprosthetic joint infection remains a common and significant complication and reason for failure in both groups. Overall, synthetic mesh showed equivalent extensor mechanism reconstruction success as allograft but with much lower cost, near universal availability, lack of disease transmission, and potential for diminishing graft stretch-out. Future research in larger case series or comparative study is needed to help aid in management of this largely unsolved problem in total knee reconstruction.

      PubDate: 2018-01-09T19:18:37Z
      DOI: 10.1016/j.knee.2017.12.004
  • Interleukin-6 and leptin levels are associated with preoperative pain
           severity in patients with osteoarthritis but not with acute pain after
           total knee arthroplasty
    • Authors: Syed Azim; James Nicholson; Mario J. Rebecchi; William Galbavy; Tian Feng; Sabeen Rizwan; Ruth A. Reinsel; Martin Kaczocha; Helene Benveniste
      Abstract: Publication date: Available online 8 January 2018
      Source:The Knee
      Author(s): Syed Azim, James Nicholson, Mario J. Rebecchi, William Galbavy, Tian Feng, Sabeen Rizwan, Ruth A. Reinsel, Martin Kaczocha, Helene Benveniste
      Background Identifying drivers of pain that can serve as novel drug targets is important for improving perioperative analgesia. Total knee arthroplasty (TKA) is associated with significant postoperative pain. Cytokines contribute to the pathophysiology of osteoarthritis (OA) and associated pain. However, the influence of perioperative cytokine levels after TKA surgery upon postoperative pain remains unexplored. Methods We designed a prospective observational study to profile three proinflammatory cytokines, interleukin-6 (IL-6), tumor necrosis factor α (TNFα), and leptin in serum, synovial, and cerebrospinal fluid of TKA patients perioperatively to determine associations between cytokine levels and pain. We characterized time-trajectories in cytokines pre- and post-surgery and explored their relationships to pain across gender. Results Preoperative pain, measured by functional pain disability scores (PDQ), was predictive of postoperative pain. There were no gender differences in severity of preoperative pain or acute postoperative pain. Serum IL-6, serum leptin, and synovial fluid leptin were positively correlated with body mass index and preoperative pain severity. Stratification of patients by gender revealed strong correlations between serum IL-6, leptin, and PDQ only in females, suggesting that females may be more sensitive to the nociceptive actions of these cytokines. Although serum IL-6 increased dramatically (and TNFα increased modestly) four hours after surgery and remained elevated at 72h; they were not associated with the severity of acute postoperative pain. Conclusions Our data suggest that while preoperative chronic pain is predictive of the severity of acute postoperative pain in TKA patients, the pre- and post-operative inflammatory status does not predict postoperative pain.

      PubDate: 2018-01-09T19:18:37Z
      DOI: 10.1016/j.knee.2017.12.001
  • Anterior tibial laxity using the GNRB® device in healthy knees
    • Authors: Y. Alqahtani; J. Murgier; P. Beaufils; P. Boisrenoult; C. Steltzlen; N. Pujol
      Abstract: Publication date: Available online 5 January 2018
      Source:The Knee
      Author(s): Y. Alqahtani, J. Murgier, P. Beaufils, P. Boisrenoult, C. Steltzlen, N. Pujol
      Background GRNB® is a non-radiating power tool that allows the evaluation of the anterior tibial translation. Hypothesis: The pressure exerted by the system against the patella and the body mass index (BMI) could affect the anterior tibial translation when we repeat the measurements in healthy knees. Materials and methods We retrospectively evaluated the measurements of anterior knee laxity in healthy knees carried out by the GNRB® in 69 consecutive patients who underwent anterior cruciate ligament (ACL) repair in the contralateral knee. Two measurements were carried out, the initial measurements (M1), and then repeated at a mean of seven months (M2) (4.9 to 13months). Results There were 38 women and 31 men with an average age of 31years. In healthy knees, the Mean average anterior translation was 5.4±4mm with an average patellar force of 35.8 at time M1. The average anterior translation was 4.9±4mm with an average patellar force of 47 at time M2. There was a significant difference between the measurements M1 and M2 (P <0.03). The tightening force was significantly different between the two sets of measurements (P <10–7). There was a negative correlation between the pressure applied on the patella and anterior knee laxity (P <0.01). Conclusion The pressure force exerted on the patella during GNRB® affects the measurement of anterior laxity in healthy knees. This raises the problem of the reproducibility of the measurements during repeated examinations at different times.

      PubDate: 2018-01-09T19:18:37Z
      DOI: 10.1016/j.knee.2017.03.004
  • Visual knee-kinetic biofeedback technique normalizes gait abnormalities
           during high-demand mobility after total knee arthroplasty
    • Authors: Jesse C. Christensen; Paul C. LaStayo; Robin L. Marcus; Gregory J. Stoddard; K. Bo Foreman; Ryan L. Mizner; Christopher L. Peters; Christopher E. Pelt
      Abstract: Publication date: Available online 2 January 2018
      Source:The Knee
      Author(s): Jesse C. Christensen, Paul C. LaStayo, Robin L. Marcus, Gregory J. Stoddard, K. Bo Foreman, Ryan L. Mizner, Christopher L. Peters, Christopher E. Pelt
      Background Abnormal knee mechanics frequently follow total knee arthroplasty (TKA) surgery with these deficits amplifying as task demands increase. Knee-kinetic biofeedback could provide a means of attenuating gait abnormalities. The purposes of this study were as follows: (1) to describe the gait characteristic differences between patients with TKA and non-TKA adults during level (low-demand) and decline (high-demand) walking; and (2) where differences existed, to determine the impact of knee-kinetic biofeedback on normalizing these abnormalities. Methods Twenty participants six months following a primary TKA and 15 non-TKA peers underwent gait analysis testing during level and decline walking. Knee-kinetic biofeedback was implemented to patients with TKA to correct abnormal gait characteristics if observed. Results Patients with TKA had lower knee extensor angular impulse (p<0.001), vGRF (p=0.001) and knee flexion motion (p=0.005) compared to the non-TKA group during decline walking without biofeedback. Patients with TKA normalized their knee extensor angular impulse (p=0.991) and peak vGRF (p=0.299) during decline walking when exposed to biofeedback. No between-group differences were observed during level walking. Groups were similar in age, gender, body mass index, physical activity level, pain interference and depression scores (p>0.05). Conclusion Patients with TKA demonstrate abnormal gait characteristics during a high-demand walking task when compared to non-TKA peers. Our findings indicate that knee-kinetic biofeedback can induce immediate improvements in gait characteristics during a high-demand walking task. There may be a potential role for the use of visual knee-kinetic biofeedback techniques to improve gait abnormalities during high-demand tasks following TKA.

      PubDate: 2018-01-03T18:49:39Z
      DOI: 10.1016/j.knee.2017.11.010
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Heriot-Watt University
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