We report a retrospective analysis of the results of combined arthroscopically-assisted posterior cruciate ligament reconstruction and open reconstruction of the posterolateral corner in 19 patients with chronic (three or more months) symptomatic instability and pain in the knee.

All the operations were performed between 1996 and 2003 and all the patients were assessed pre- and post-operatively by physical examination and by applying three different ligament rating scores. All also had weight-bearing radiographs, MR scans and an examination under anaesthesia and arthroscopy pre-operatively. The posterior cruciate ligament reconstruction was performed using an arthroscopically-assisted single anterolateral bundle technique and the posterolateral corner structures were reconstructed using an open Larson type of tenodesis.

The mean follow up was 66.8 months (24 to 110). Pre-operatively, all the patients had a grade III posterior sag according to Clancy and demonstrated more than 20° of external rotation compared with the opposite normal knee on the Dial test. Post-operatively, seven patients (37%) had no residual posterior sag, 11 (58%) had a grade I posterior sag and one (5%) had a grade II posterior sag. In five patients (26%) there was persistent minimal posterolateral laxity. The Lysholm score improved from a mean of 41.2 (28 to 53) to 76.5 (57 to 100) (p = 0.0001) and the Tegner score from a mean of 2.6 (1 to 4) to 6.4 (4 to 9) (p = 0.0001).

We conclude that while a combined reconstruction of chronic posterior cruciate ligament and posterolateral corner instability improves the function of the knee, it does not restore complete stability.

We assessed proprioception in the knee using the angle reproduction test in 20 healthy volunteers, ten patients with acute anterior instability and 20 patients with chronic anterior instability after reconstruction of the anterior cruciate ligament (ACL). In addition, the Lysholm-knee score, ligament laxity and patient satisfaction were determined.

Acute trauma causes extensive damage to proprioception which is not restored by rehabilitation alone. Three months after operation, there remained a slight decrease in proprioception compared with the preoperative recordings, but six months after reconstruction, restoration of proprioception was seen near full extension and full flexion. In the mid-range position, proprioception was not restored. At follow-up, 3.7 ± 0.3 years after reconstruction, there was further improvement of proprioception in the mid-range position. There was no difference between open and arthroscopic techniques. The highest correlation was found between proprioception and patient satisfaction. After reconstruction of the ACL reduced proprioception may explain the poor functional outcome in some patients, despite restoration of mechanical stability.

Aims. A functional anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) has been assumed to be required for patients undergoing unicompartmental knee arthroplasty (UKA). However, this assumption has not been thoroughly tested. Therefore, this study aimed to assess the biomechanical effects exerted by cruciate ligament-deficient knees with medial UKAs regarding different posterior tibial slopes. Methods. ACL- or PCL-deficient models with posterior tibial slopes of 1°, 3°, 5°, 7°, and 9° were developed and compared to intact models. The kinematics and contact stresses on the tibiofemoral joint were evaluated under gait cycle loading conditions. Results. Anterior translation increased in ACL-deficient UKA cases compared with intact models. In contrast, posterior translation increased in PCL-deficient UKA cases compared with intact models. As the posterior tibial slope increased, anterior translation of ACL-deficient UKA increased significantly in the stance phase, and posterior translation of PCL-deficient UKA increased significantly in the swing phase. Furthermore, as the posterior tibial slope increased, contact stress on the other compartment increased in cruciate ligament-deficient UKAs compared with intact UKAs. Conclusion. Fixed-bearing medial UKA is a viable treatment option for patients with cruciate ligament deficiency, providing a less invasive procedure and allowing patient-specific kinematics to adjust posterior tibial slope. Patient selection is important, and while AP kinematics can be compensated for by posterior tibial slope adjustment, rotational stability is a prerequisite for this approach. ACL- or PCL-deficient UKA that adjusts the posterior tibial slope might be an alternative treatment option for a skilled surgeon. Cite this article: Bone Joint Res 2022;11(7):494–502

Objectives. The aim of this study was to investigate the biomechanical effect of the anterolateral ligament (ALL), anterior cruciate ligament (ACL), or both ALL and ACL on kinematics under dynamic loading conditions using dynamic simulation subject-specific knee models. Methods. Five subject-specific musculoskeletal models were validated with computationally predicted muscle activation, electromyography data, and previous experimental data to analyze effects of the ALL and ACL on knee kinematics under gait and squat loading conditions. Results. Anterior translation (AT) significantly increased with deficiency of the ACL, ALL, or both structures under gait cycle loading. Internal rotation (IR) significantly increased with deficiency of both the ACL and ALL under gait and squat loading conditions. However, the deficiency of ALL was not significant in the increase of AT, but it was significant in the increase of IR under the squat loading condition. Conclusion. The results of this study confirm that the ALL is an important lateral knee structure for knee joint stability. The ALL is a secondary stabilizer relative to the ACL under simulated gait and squat loading conditions. Cite this article: Bone Joint Res 2019;8:509–517

Abstract. Purpose. Since arthroscopic reconstruction of the anterior cruciate ligament (ACL) started, the use of peroneus longus grafts for primary ACL reconstruction (ACLR) was never thought of as there is very scant literature on it. So, our study aims to compare the functional outcome and complications in patients with ACL injury managed by ACLR with peroneus longus tendon (PLT) and hamstring tendons (HT) respectively. Materials and Methods. Patients with 16–50 years of either gender presenting with symptomatic ACL deficiency were admitted for arthroscopic single bundle ACLR and allocated into two groups (PLT and HT) operated and observed. Functional scores (IKDC and Lysholm score), clinical knee evaluation, donor site morbidity (AOFAS score) and thigh circumference were recorded preoperatively and at six months, one year post-operatively. The same post-op rehabilitation protocol was followed in both groups. Results. 194 patients (hamstring n=96, peroneus n=98) met the inclusion criteria. There were no significant differences between the pre-op, six months post-op and one-year postoperative score between the hamstring and peroneus longus groups in the IKDC (p=0.356) and Lysholm knee score (p=0.289). The mean for the AOFAS was 99.05±3.56 and 99.80±0.70 in the PLT and HT group respectively showing no statistical difference, with a significant improvement in thigh muscle wasting among the PLT group at final follow-up (p<0.001). Conclusion. We observed similar knee stability, functional outcome and no obvious donor site morbidity among both groups and recommend that a PL graft may be a safe, effective, and viable option for arthroscopic single bundle ACL reconstruction

Abstract. Introduction. Previous research has shown that, notwithstanding ligament healing, properly selected MCL reconstruction can restore normal knee stability after MCL rupture. The hypothesis of this work was that it is possible to restore knee stability (particularly valgus and AMRI) with simplified and/or less-invasive MCL reconstruction methods. Methods. Nine unpaired human knees were cleaned of skin and fat, then digitization screws and optical trackers were attached to the femur and tibia. A Polaris stereo camera measured knee kinematics across 0. o. -100. o. flexion when the knee was unloaded then with 90N anterior-posterior force, 9Nm varus-valgus moment, 5Nm internal-external rotation, and external+anterior (AMRI) loading. The test was conducted for the following knee conditions: intact, injured: transected superficial and deep MCL (sMCL and dMCL), and five reconstructions: (long sMCL, long sMCL+dMCL, dMCL, short sMCL+dMCL, short sMCL), all based on the medial epicondyle isometric point and using 8mm tape as a graft, with long sMCL 60mm below the joint line (anatomical), short sMCL 30mm, dMCL 10mm (anatomical). Results. No significant changes were found in anterior or posterior translation, or varus at any stage. MCL deficiency caused increased valgus, external rotation and AMRI instabilities. All reconstructions restored valgus stability. The isolated long sMCL allowed residual external rotation and AMRI instability, while the short sMCL did stabilise AMRI. Both 2-strand reconstructions (dMCL+sMCL) restored stability. Conclusion. All tested techniques, except long sMCL, restored valgus and AMRI stability of the knee. The single femoral tunnel is satisfactory for both the dMCL and sMCL grafts

Abstract. Introduction. MCL injuries often occur concurrently with ACL rupture – most noncontact ACL injuries occur in valgus and external rotation (ER) - and conservative MCL treatment leads to increased rate of ACL reconstruction failure. There has been little work developing effective MCL reconstructions. Methods. Cadaveric work measured MCL attachments by digitisation and radiographically, relating them to anatomical landmarks. The isometry of the superficial and deep MCL (sMCL and dMCL) and posterior oblique ligament (POL) was measured using fine sutures led to displacement transducers. Contributions to stability (restraint) were measured in a robotic testing system. Two MCL reconstructions were designed and tested: 3-strand reconstruction (sMCL+dMCL+POL), and 2-strand method (sMCL+dMCL) addressing anteromedial rotatory instability (AMRI). The resulting stability was measured in a kinematics test rig, and compared to the ‘anatomic’ sMCL+POL reconstruction of LaPrade. Results. The sMCL was isometric, centred on the medial epicondyle, and the primary restraint of valgus. The dMCL elongated rapidly in ER, and was the primary restraint of ER near knee extension. The POL slackened rapidly with flexion and only stabilised the knee near extension. With sMCL+dMCL+POL deficiency (‘grade 3’), the 2-strand AM reconstruction restored all stability measures to native, apart from internal rotation. The 3-strand reconstruction restored all stability measures to native. The LaPrade reconstruction did not control ER, lacking a dMCL graft, or valgus in flexion, being anisometric. Conclusions. This work has revealed the importance of the dMCL in stabilising AMRI as part of anatomical MCL reconstruction, with the sMCL restraining valgus

Introduction. Low serum Vitamin D (VitD) levels are often found in patients being investigated for Total Knee Arthroplasty (TKA). VitD deficiency is associated with poor pre/post-operative functional scores and higher rate of complications. Studies report VitD as an important modifiable risk factor to improve outcomes post TKA. Aim. Aim of our study was 1) To examine the trajectory of VitD in TKA patients over 2 weeks, which included VitD sufficient and deficient patients who were supplemented orally or intramuscularly (IM) for comparision. 2) To compare early (2weeks) functional recovery in VitD sufficient and deficient patients. Material & Methods. We prospectively enrolled patients undergoing primary TKA by a single surgeon. Based on preoperative VitD levels (25OH VitD ≥30 being sufficient or <30 ng/mL being deficient) and means of supplementation(none, IM or Oral Injection Arachitol, Cholecalciferol IP 6,00,000 IU), we formed three groups: Group A (VitD sufficient, no supplementation); Group B (VitD deficient, IM supplementation); and Group C (VitD deficient, Oral supplementation). Study was approved by ethics committee. All patients gave informed consent and underwent TKA by same surgeon with uniform intra/post-operative protocols. VitD deficiency was supplemented orally/IM on the morning of surgery based on their randomization sequence. VitD levels (ng/mL) and outcome parameters of Flexion (degrees) and Timed up-and-go (TUG) test in seconds were assessed preoperatively and postoperatively on Day 3 and 14. 60 patients (20 per group) were enrolled. Demographics of all three groups were comparable. Results. VitD:. Group A:. Mean preoperative level of 42.3, fell to mean 40.4 by Day 3 (p < 0.001), and further to mean 38.9 by Day 14 (p<0.001). 6 and 4 patients became VitD deficient by Day 3 and Day 14 respectively. Group B:. Mean preoperative level of 21.5 rose to 31.2 by Day 3 (p=0.06), and further to 36.9 by Day 14 (p=0.001). 7 and 11 patients became sufficient by Day 3 and Day 14 respectively. Group C:. Mean preoperative level of 20.2 rose to mean 69.9 by Day 3 (p<0.001) and to a mean of 67.2 by Day 14 (p < 0.001). 19 and 20 patients became sufficient by Day 3 and Day 14 respectively. Outcome. Flexion:. Preoperative Flexion in Groups A, B, C was 133, 129 & 125 respectively (p=0.5). Day 3 Flexion was 88, 84 & 83 (p=0.2); Day 14 Flexion was 99, 90 & 95 (p=0.013) respectively. Posthoc Schaffe test showed statistical significance (p<0.05) only between Group A (99) and Group B (90) at Day 14. This indicated better flexion achieved in VitD sufficient patients at 2 weeks than in deficient patients with IM supplementation. TUG Test. was 17.1, 14.1 & 14.7 preoperatively in Groups A, B, C (p=0.5); on Day 3, it was 52.5, 62.6 & 58.2 (p=0.07); on Day 14, it was 33, 38.8 & 37.8 (p=0.2) respectively. Day 3 TUG time was longest (62.6) in Group B and shortest (52.5) in Group A indicating that IM supplemented patients had poor function compared to sufficient group though without statistical significance (p=0.07) with numbers available. Conclusion. We found that VitD deficient patients can be rapidly supplemented on the morning of surgery. High dose oral VitD increased levels by Day 3, whereas IM VitD increased levels only by Day 14 which remained significantly lesser than oral group. Interestingly, about 25% of VitD sufficient patients who were not supplemented, became deficient postoperatively. Flexion achieved on Day 14 was significantly better with VitD sufficiency, compared to deficient patients treated with IM VitD. Significance. VitD deficiency can be rapidly corrected by high dose oral supplementation on the morning of surgery. Also, TKA can deplete VitD and can make VitD sufficient patients deficient as early as Day 3 post surgery. For figures, tables, or references, please contact authors directly

Objectives. The aim of the current study was to analyse the effects of posterior cruciate ligament (PCL) deficiency on forces of the posterolateral corner structure and on tibiofemoral (TF) and patellofemoral (PF) contact force under dynamic-loading conditions. Methods. A subject-specific knee model was validated using a passive flexion experiment, electromyography data, muscle activation, and previous experimental studies. The simulation was performed on the musculoskeletal models with and without PCL deficiency using a novel force-dependent kinematics method under gait- and squat-loading conditions, followed by probabilistic analysis for material uncertain to be considered. Results. Comparison of predicted passive flexion, posterior drawer kinematics and muscle activation with experimental measurements showed good agreement. Forces of the posterolateral corner structure, and TF and PF contact forces increased with PCL deficiency under gait- and squat-loading conditions. The rate of increase in PF contact force was the greatest during the squat-loading condition. The TF contact forces increased on both medial and lateral compartments during gait-loading conditions. However, during the squat-loading condition, the medial TF contact force tended to increase, while the lateral TF contact forces decreased. The posterolateral corner structure, which showed the greatest increase in force with deficiency of PCL under both gait- and squat-loading conditions, was the popliteus tendon (PT). Conclusion. PCL deficiency is a factor affecting the variability of force on the PT in dynamic-loading conditions, and it could lead to degeneration of the PF joint. Cite this article: K-T. Kang, Y-G. Koh, M. Jung, J-H. Nam, J. Son, Y.H. Lee, S-J. Kim, S-H. Kim. The effects of posterior cruciate ligament deficiency on posterolateral corner structures under gait- and squat-loading conditions: A computational knee model. Bone Joint Res 2017;6:31–42. DOI: 10.1302/2046-3758.61.BJR-2016-0184.R1

Most patients (95%) with fibular hemimelia have an absent anterior cruciate ligament (ACL). The purpose of this study was to assess the long-term outcome of such patients with respect to pain and knee function. We performed a retrospective review of patients with fibular hemimelia and associated ACL deficiency previously treated at our institution. Of a possible 66 patients, 23 were sent the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS) questionnaire and Lysholm knee score to complete. In all, 11 patients completed the MODEMS and nine completed the Lysholm score questionnaire. Their mean age was 37 years (27 to 57) at review. Five patients had undergone an ipsilateral Symes amputation. There was no significant difference in any subsections of the Short-Form 36 scores of our patients compared with age-matched controls. The mean Lysholm knee score was 90.2 (82 to 100). A slight limp was reported in six patients. No patients had episodes of locking of the knee or required a supportive device for walking. Four had occasional instability with sporting activities. . These results suggest that patients with fibular hemimelia and ACL deficiency can live active lives with a similar health status to age-matched controls

Aims

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration.

The options for treatment of the young active patient with isolated symptomatic osteoarthritis of the medial compartment and pre-existing deficiency of the anterior cruciate ligament are limited. The potential longevity of the implant and levels of activity of the patient may preclude total knee replacement, and tibial osteotomy and unicompartmental knee arthroplasty are unreliable because of the ligamentous instability. Unicompartmental knee arthroplasties tend to fail because of wear or tibial loosening resulting from eccentric loading. Therefore, we combined reconstruction of the anterior cruciate ligament with unicompartmental arthroplasty of the knee in 15 patients (ACLR group), and matched them with 15 patients who had undergone Oxford unicompartmental knee arthroplasty with an intact anterior cruciate ligament (ACLI group). The clinical and radiological data at a minimum of 2.5 years were compared for both groups. The groups were well matched for age, gender and length of follow-up and had no significant differences in their pre-operative scores. At the last follow-up, the mean outcome scores for both the ACLR and ACLI groups were high (Oxford knee scores of 46 (37 to 48) and 43 (38 to 46), respectively, objective Knee Society scores of 99 (95 to 100) and 94 (82 to 100), and functional Knee Society scores of 96 and 96 (both 85 to 100). One patient in the ACLR group needed revision to a total knee replacement because of infection. No patient in either group had radiological evidence of component loosening. The radiological study showed no difference in the pattern of tibial loading between the groups. The short-term clinical results of combined anterior cruciate ligament reconstruction and unicompartmental knee arthroplasty are excellent. The previous shortcomings of unicompartmental knee arthroplasty in the presence of deficiency of the anterior cruciate ligament appear to have been addressed with the combined procedure. This operation seems to be a viable treatment option for young active patients with symptomatic arthritis of the medial compartment, in whom the anterior cruciate ligament has been ruptured

Aims

The aim of this study was to evaluate medium- to long-term outcomes and complications of the Stanmore Modular Individualised Lower Extremity System (SMILES) rotating hinge implant in revision total knee arthroplasty (rTKA) at a tertiary unit. It is hypothesized that this fully cemented construct leads to satisfactory clinical outcomes.

Aims

Implantation of ultra-purified alginate (UPAL) gel is safe and effective in animal osteochondral defect models. This study aimed to examine the applicability of UPAL gel implantation to acellular therapy in humans with cartilage injury.

Aims

Unicompartmental knee arthroplasty (UKA) has higher revision rates than total knee arthroplasty (TKA). As revision of UKA may be less technically demanding than revision TKA, UKA patients with poor functional outcomes may be more likely to be offered revision than TKA patients with similar outcomes. The aim of this study was to compare clinical thresholds for revisions between TKA and UKA using revision incidence and patient-reported outcomes, in a large, matched cohort at early, mid-, and late-term follow-up.

Aims

In-hospital length of stay (LOS) and discharge dispositions following arthroplasty could act as surrogate measures for improvement in patient pathways, and have major cost saving implications for healthcare providers. With the ever-growing adoption of robotic technology in arthroplasty, it is imperative to evaluate its impact on LOS. The objectives of this study were to compare LOS and discharge dispositions following robotic arm-assisted total knee arthroplasty (RO TKA) and unicompartmental arthroplasty (RO UKA) versus conventional technique (CO TKA and UKA).

Aims

The aim of this study was to identify variables associated with time to revision, demographic details associated with revision indication, and type of prosthesis employed, and to describe the survival of hinge knee arthroplasty (HKA) when used for first-time knee revision surgery and factors that were associated with re-revision.

Aims

This study aimed to explore the biological and clinical importance of dysregulated key genes in osteoarthritis (OA) patients at the cartilage level to find potential biomarkers and targets for diagnosing and treating OA.

Introduction. Emergency department (ED) visits following primary total knee arthroplasty (TKA) can lead to poor patient satisfaction, potentially unnecessary readmissions, and greater overall healthcare costs. Reasons for post-operative ED visits are often entirely medical in nature and can be independent of the recent operation. Several strategies have been developed to help reduce ED visits. However, one major factor that can play a critical role in addressing potentially avoidable visits is provider and patient education. A major factor that can play a crucial role in addressing potentially avoidable visits is provider and patient education. It follows that a thorough understanding of which patients are visiting the ED and why can help in avoiding the visits. Therefore, the purpose of this study was to investigate: 1) causes and 2) patient-related factors (demographics and comorbidities) associated with ED visits following primary TKA. Methods. A national private payer database was queried for primary TKAs performed between 2007 and 2016 using the International Classification of Disease, ninth revision (ICD-9) procedural code 81.54. ED visits were identified using Current Procedural Terminology (CPT) codes 99281 to 99285. Patients with 90-day ED visits were in the study group (n=28,044) whereas those without 90-day ED visits served as controls (n=82,289). Causes for ED visits were divided into cardiopulmonary, gastrointestinal, renal, thromboembolic, leg pain, or wound-related. Patient demographics and risk factors assessed included age, gender, and body mass index (BMI) as well as several comorbidities (Table 1). Pearson's chi-square tests were performed to compare patient demographics and comorbidities between the cohorts. In order to adjust for potential confounders, multivariate binomial logistic regression analysis was performed to further evaluate the associations between patient factors and 90-day ED visits. A p-value less than 0.01 was considered statistically significant. Results. The most common reasons for ED visits were cardiopulmonary (51.30%), leg/back pain (46.20%), and gastrointestinal (31.60%) reasons. There was a greater proportion of women in the ED visit cohort compared to controls (p<0.0001; Table 1) and comorbidities (p<0.0001). Multivariate analysis revealed that patients with a history of COPD (odds ratio [OR] 1.48, p<0.001), depression (OR 1.42, p<0.0001), arrhythmias (OR: 1.38, p<0.0001), AIDS (O: 1.32, p<0.0001), and iron deficiency anemia (OR 1.28, p<0.0001), were at an increased risk of visting the ED within 90 days following primary TKA (Table 2). Conclusion. This analysis of over 100,000 patients identified that the most common reasons for ED visits are primarily medical in nature, and are not necessarily directly related to the recent operation. These findings should help guide pre-operative education and manage post-operative expectations to help limit potentially avoidable ED visits. Additionally, the data from this study can lend to policy changes targeting ED visits, particularly given the shift towards certain reimbursement models in arthroplasty. For figures, tables, or references, please contact authors directly

Aims

Meniscal allograft transplantation (MAT) for patients with symptomatic meniscal loss has demonstrated good clinical results and survivorship. Factors that affect both functional outcome and survivorship have been reported in the literature. These are typically single-centre case series with relatively small numbers and conflicting results. Our aim was to describe an international, two-centre case series, and identify factors that affect both functional outcome and survival.