Aims. Meniscal injuries are common and often induce knee pain requiring surgical intervention. To develop effective strategies for meniscus regeneration, we hypothesized that a minced meniscus embedded in an atelocollagen gel, a firm gel-like material, may enhance meniscus regeneration through cell migration and proliferation in the gel. Hence, the objective of this study was to investigate cell migration and proliferation in atelocollagen gels seeded with autologous meniscus fragments in vitro and examine the therapeutic potential of this combination in an in vivo rabbit model of massive meniscus defect. Methods. A total of 34 Japanese white rabbits (divided into defect and atelocollagen groups) were used to produce the massive meniscus defect model through a medial patellar approach. Cell migration and proliferation were evaluated using immunohistochemistry. Furthermore, histological evaluation of the sections was performed, and a modified Pauli’s scoring system was used for the quantitative evaluation of the regenerated meniscus. Results. In vitro immunohistochemistry revealed that the meniscus cells migrated from the minced meniscus and proliferated in the gel. Furthermore, histological analysis suggested that the minced meniscus embedded in the atelocollagen gel produced tissue resembling the native meniscus in vivo. The minced meniscus group also had a higher Pauli’s score compared to the defect and atelocollagen groups. Conclusion. Our data show that cells in minced meniscus can proliferate, and that implantation of the minced meniscus within atelocollagen induces meniscus regeneration, thus suggesting a novel therapeutic alternative for meniscus tears. Cite this article: Bone Joint Res 2021;10(4):269–276

Abstract. Aims. We studied the outcomes following arthroscopic primary repair of bucket handle meniscus tears to determine the incidence of re-tears and the functional outcomes of these patients. Methodology. Prospective cohort study. Over a 4-year period (2016 to 2020), 35 adult patients presented with a bucket handle tear of the meniscus. Arthroscopic meniscal repair was performed using either the all inside technique or a combination of all-inside and inside-out techniques. 15 patients also underwent simultaneous arthroscopic anterior cruciate ligament reconstruction. Functional knee scores were assessed using IKDC and Lysholm scores. Results. Mean patient age at surgery was 27 years (range, 17 to 53years). Medial meniscus was torn in 20 and lateral in 15 cases. Zone of tear was white on white in 19, red on white in 9 and red on red in 7 cases. Average delay from injury to surgery was 4 months. At a mean follow-up of 4.5 years, the meniscus repair failed in 3 patients (8.5 %). Outcome following re-tear was meniscus excision. Average IKDC scores in patients with intact repair were 74.04 against 56.67 in patients with a failed repair (p< 0.0001). Similarly, Lyshlom scores were 88.96 and 67.333, respectively (p<0.0001). Conclusion. The survivorship of primary repair of bucket handle meniscus tears in our series was 91.5% at medium term follow-up. Functional outcomes were significantly poor in patients with a failed repair compared to those with an intact repair

Aims. This study aims to identify the top unanswered research priorities in the field of knee surgery using consensus-based methodology. Methods. Initial research questions were generated using an online survey sent to all 680 members of the British Association for Surgery of the Knee (BASK). Duplicates were removed and a longlist was generated from this scoping exercise by a panel of 13 experts from across the UK who provided oversight of the process. A modified Delphi process was used to refine the questions and determine a final list. To rank the final list of questions, each question was scored between one (low importance) and ten (high importance) in order to produce the final list. Results. This consensus exercise took place between December 2020 and April 2022. A total of 286 clinicians from the BASK membership provided input for the initial scoping exercise, which generated a list of 105 distinct research questions. Following review and prioritization, a longlist of 51 questions was sent out for two rounds of the Delphi process. A total of 42 clinicians responded to the first round and 24 responded to the second round. A final list of 24 research questions was then ranked by 36 clinicians. The topics included arthroplasty, infection, meniscus, osteotomy, patellofemoral, cartilage, and ligament pathologies. The management of early osteoarthritis was the highest-ranking question. Conclusion. A Delphi exercise involving the BASK membership has identified the future research priorities in knee surgery. This list of questions will allow clinicians, researchers, and funders to collaborate in order to deliver high-quality research in knee surgery and further advance the care provided to patients with knee pathology. Cite this article: Bone Joint J 2024;106-B(7):662–668

This study evaluates high power low frequency ultrasound transmitted via a flat vibrating probe tip as an alternative technology for meniscal debridement in the knee. A limitation of this technology is thermal damage in residual meniscal tissue. An experimental force controlled testing rig was constructed using a 20kHz ultrasonic probe suspended vertically from a load cell. Ex-vivo bovine meniscus samples were harvested from knee joints and cut into uniform 16mm discs. Effect of variation in force (2.5-4.5N) and amplitude of distal tip displacement (242-494μm peak-peak) settings on tissue removal rate (TRR) and penetration rate (PR) was analysed. Temperature elevation in the residual meniscus was measured by embedded thermocouples and residual meniscus histological analysis. The experiment was designed using a response surface quadratic model with input variables treated as continuous, using Design-Expert v.8.0 (Stat-Ease Inc., Minneapolis, MN). Statistical analysis was conducted using PASW Statistics v.18.0 (IBM SPSS Inc., Chicago, IL). As either force or amplitude increases, there is a linear increase in TRR (Mean±SD: 0.9±0.4 to 11.2±4.9mg/s). A corresponding increase is observed in PR (Mean±SD: 0.08±0.04 to 0.73±0.18mm/s). Maximum mean temperatures of 84.6±12.1°C and 52.3±10.9°C were recorded in residual tissue at 2mm and 4mm from the ultrasound probe-tissue interface. Minimum depth of the zone of thermal alteration in residual tissue was 177.4μm. There is an inverse relationship between both amplitude and force, and temperature elevation, with higher amplitude and force settings resulting in less thermal damage. Ultrasonic debridement shows comparable thermal damage to existing meniscal debridement technologies

Purposes of the study. To assess the performance of an acellular synthetic scaffold in the treatment of painful partial meniscal tissue loss. Methods. Subjects recruited (n=52) had irreparable medial or lateral meniscus partial meniscus loss, intact rim, presence of both horns and a stable well aligned knee. Diagnostic imaging was used to assess tissue ingrowth at 3 months post-implantation by evidence of vascularisation in the scaffold using DCE-MRI with intravenous gadolinium contrast material (n=42). All DCE-MRI scans were assessed centrally for neovascularisation in the peripheral half of the scaffold meniscus and integration of the implanted device. Stability of tissue ingrowth and cartilage scores in the index compartment were assessed at 12 and 24 months post-implantation using anatomic MRI scans. Results. The 52 patients recruited (75% males) had a mean age of 30.8 ± 9.4 years and mean longitudinally measured lesions of 47.1 ± 10.0 mm, involving 34 medial and 18 lateral indications. At 3 months post-implantation tissue ingrowth was demonstrated in the peripheral half of the scaffold, in 36/42 (85.7%) subjects. To date stable or improved cartilage scores were seen in the index compartment at 12 months (n= 47) and 24 months (n=9). No signs of an inflammatory reaction to the scaffold or its degradation products were observed. The tissue observed on MRI at 12 months (n=47) remained stable at 24 months (n=9). No safety issues related to the scaffold were reported. Conclusions. These preliminary results indicate that this novel scaffold induces ingrowth of stable tissue

Purpose. To assess performance of a polyurethane scaffold designed to facilitate regrowth of tissue after irreparable partial meniscus tissue loss. Methods. Fifty-two subjects with irreparable medial or lateral meniscus tissue lesions with intact rim, presence of both horns and stable, well aligned knees, were treated with the scaffold. Tissue ingrowth was assessed using dynamic contrast enhanced MRI (DCE-MRI) at 3 months (n=43), and by histological examination of biopsies (n=44) at 12 months relook arthroscopy. Cartilage status on MRI at 1week, 3, 12 and 24 months, and clinical outcomes were assessed from baseline to 24 months using Visual Analogue Scale (VAS), Knee and Osteoarthritis Outcome Score (KOOS), Lysholm and International Knee Documentation Committee (IKDC). Results. Clinically and statistically significant improvements on all outcome scores were observed at 6, 12 and 24 months. On MRI, stable or improved ICRS scores in all but 3 subjects (n=40) at 24 months were observed, with no signs of scaffold related cartilage damage. All biopsies contained vital material, with no signs of necrosis, cell death (presence of cell pods, ghost cells, cells with defragmented nuclei), or adverse reaction to the scaffold or its degradation products. A fibrous capsule and three distinct layers were observed, each with its own unique histological characteristics, including presence or absence of vessel structures, and the composition of extracellular matrix. In one case with unknown causality, the scaffold did not integrated with the native tissue. No safety issues related to the scaffold were reported. Conclusions. These data demonstrate the safety and performance of the polyurethane scaffold and illustrate new tissue generation resulting in significant pain reduction and functional improvement

Aims. The aim of this study was to compare patient-reported outcomes (PROMs) following isolated anterior cruciate ligament reconstruction (ACLR), with those following ACLR and concomitant meniscal resection or repair. Methods. We reviewed prospectively collected data from the UK National Ligament Registry for patients who underwent primary ACLR between January 2013 and December 2022. Patients were categorized into five groups: isolated ACLR, ACLR with medial meniscus (MM) repair, ACLR with MM resection, ACLR with lateral meniscus (LM) repair, and ACLR with LM resection. Linear regression analysis, with isolated ACLR as the reference, was performed after adjusting for confounders. Results. From 14,895 ACLR patients, 4,400 had two- or five-year Knee injury and Osteoarthritis Outcome Scores (KOOS) available. At two years postoperatively, the MM repair group demonstrated inferior scores in KOOS pain (β = −3.63, p < 0.001), symptoms (β = − 4.88, p < 0.001), ADL (β = − 2.43, p = 0.002), sport and recreation (β = − 5.23, p < 0.001), quality of life (QoL) (β = − 5.73, p < 0.001), and International Knee Documentation Committee (β = − 4.1, p < 0.001) compared with the isolated ACLR group. The LM repair group was associated with worse KOOS sports and recreation scores at two years (β = − 4.264, p < 0.001). At five years, PROMs were comparable between the groups. At five years, PROMs were comparable between the groups. Participants undergoing ACLR surgery within 12 weeks from index injury demonstrated superior PROMs at two and five years. Conclusion. Our study showed that MM repair, and to a lesser extent LM repairs in combination with ACLR, were associated with inferior patient-reported outcome measures (PROMs) compared to isolated ACLR at two years postoperatively, while meniscal resection groups exhibited comparable outcomes. However, by five years postoperation, no significant differences in PROMs were evident. Further longer-term, cross-sectional studies are warranted to investigate the outcomes of ACLR and concomitant meniscal surgery

Abstract. Introduction. Augmentation of meniscus repairs with fibrin clot may enhance the healing capacity. Pulling the clot into the tear with a suture ensures that it stays in position. This paper aims to assess the outcome of this technique. Methods. 52 patients over 4 years undergoing suture repair of a meniscus tear with blood clot augmentation were collected from a prospective database. Follow up included outcome scores and a questionnaire. Failure was defined as pain or further surgery secondary to meniscal pathology. Results. There were 32 males and 20 females, mean age of 35 (14–70). The medial meniscus was repaired in 32 knees and the lateral in 20. Complete radial tears were the most common type. Only 2% of tears were in the red-red zone. Follow-up ranged from 12 months to 7 years. Only 1 patient is known to have come to subsequent arthroscopy. Lysholm scores improved from 53.97 (SD 18.14) to 92.08 (SD 8.97), Oxford Knee Scores from 29.84 (SD 9.65) to 45.79 (SD 2.66), KOOS pain scores from 61.49 (SD 22.76) to 93.54 (SD 8.06) and Tegner scores from 4.56 (SD 3.35) to 6.05 (SD 2.41). Conclusions. Pulling a fibrin blood clot into a meniscus tear with a suture ensures that the clot remains in place while the meniscus is repaired. Patients have shown excellent outcomes with 98% survivorship at 45 months. This is a reliable technique for augmenting meniscus repairs especially for tears which otherwise may not have been repaired

Abstract. Introduction. Meniscal repair is an accepted surgical option for meniscal tears. However, there remains trepidation with regard to offering such surgery to older patients. We aim to evaluate the outcomes in these such patients. Methodology. A single surgeons log was used to identify patients who underwent meniscal repair and were over the age of 40. Patients having concurrent anterior cruciate ligament reconstructions were excluded. Demographic data, surgical data and outcomes (pain visual analogue score (VAS); single assessment numerical evaluation (SANE) and knee injury and osteoarthritis outcome joint replacement (KOOS Jr) score) were collected prospectively. Final outcomes were collected between 6–12 months following surgery. Results. 24 meniscal tears in 22 knees (22 patients) were identified. Mean age was 52.2 (range; 40.6-70.3). Morphology of the tears were medial meniscus posterior root tear 10 (42%); medial meniscus posterior horn tear 9 (38%); lateral meniscus posterior horn tear 2 (8.3%); lateral meniscus posterior root tear 1 (4.2%); lateral meniscus body tear 1 (4.2%) and lateral meniscus anterior horn tear 1 (4.2%). Response rate was 86%. Statistically significant improvements in pain VAS (p=0.0001); SANE (p=0.0001) and KOOS Jr Score (p=0.0005) were found. 68% and 74% of patients had surpassed the MCID in their KOOS symptoms and KOOS quality of life subscales, respectively. Conclusion. Meniscal repair in patients over 40 years of age is an acceptable treatment with significant improvements in patients reported outcome measures, SANE and pain VAS

Abstract. INTRODUCTION. To preserve knee function and reduce degenerative, meniscal tears should be repaired where possible. Meniscal wrapping with collagen matrices has shown promising clinical outcome (AAOS meniscal algorithm), however there is limited basic science to support this. AIM. to model the contact pressures on the human tibial plateau beneath a (1) a repaired radial meniscal tear and (2) a wrapped and repaired radial meniscal tear. METHODOLOGY. Complete anterolateral radial tears were formed across 4 lateral human menisci, before repairing with ‘rip-stop’ H sutures using 2mm Arthrex Meniscal Suture tape. This was then repeated with the addition of a ChondroGide collagen matrix wrapping. From this experimental setup a finite element (FE) analysis model was construted. FE models of the two techniques (i) suture alone and (ii) suture and collagen-matrix wrap, were then modelled; bone was linear elastic, articular cartilage was a hyperelastic Yeoh model, and a linear elastic and transversely isotropic material model for the meniscus. The contact areas of the articulating surfaces, meniscus kinematics, and stress distribution around the repair were compared between the two systems. RESULTS. Meniscal suture-tape repair had higher local stresses and strains (σ_max=51 MPa ε_max=25%) around the repair compared to with Collagen wrapping (σ_max=36.6MPa ε_max=15%). Radial displacement and pressure on the meniscal contact surfaces were higher in the suture only repair. CONCLUSION. Collagen-matrix wrapping strengthens the repair, reducing local peak stresses and strains around the suture-tape. This could reduce the chance of suture-tape pull-out and subsequent repair failure

Aim. Mesenchymal stem cells (MSCs) have several properties that may support their use as an early treatment option for osteoarthritis (OA). This study investigated the role of multiple injections of allogeneic bone marrow-derived stem cells (BMSCs) to alleviate the progression of osteoarthritic changes in the various structures of the mature rabbit knee in an anterior cruciate ligament (ACL)-deficient OA model. Materials and Methods. Two months after bilateral section of the ACL of Japanese white rabbits aged nine months or more, either phosphate buffered saline (PBS) or 1 x 10. 6. MSCs were injected into the knee joint in single or three consecutive doses. After two months, the articular cartilage and meniscus were assessed macroscopically, histologically, and immunohistochemically using collagen I and II. Results. Within the PBS injection (control group), typical progressive degenerative changes were revealed in the various knee structures. In the single MSC injection (single group), osteoarthritic changes were attenuated, but still appeared, especially in the medial compartments involving fibrillation of the articular cartilage, osteophyte formation in the medial plateau, and longitudinal tear of the meniscus. In the multiple-injections group, the smoothness and texture of the articular cartilage and meniscus were improved. Histologically, absence or reduction in matrix staining and cellularity were noticeable in the control and single-injection groups, respectively, in contrast to the multiple-injections group, which showed good intensity of matrix staining and chondrocyte distribution in the various cartilage zones. Osteoarthritis Research Society International (OARSI) scoring showed significantly better results in the multiple-injections group than in the other groups. Immunohistochemically, collagen I existed superficially in the medial femoral condyle in the single group, while collagen II was more evident in the multiple-injections group than the single-injection group. Conclusion. A single injection of MSCs was not enough to restore the condition of osteoarthritic joints. This is in contrast to multiple injections of MSCs, which had the ability to replace lost cells, as well as reducing inflammation. Cite this article: Bone Joint J 2019;101-B:824–831

Abstract. Background. Little scientific evidence is available regarding the effect of knee joint line obliquity (JLO). Methods. 10 fresh-frozen human cadaveric knees were axially loaded to 1500 N in a materials testing machine with the joint line tilted 0, 4, 8, and 12 degrees varus and valgus, at 0, and 20 degrees of knee flexion. The mechanical compression axis was aligned to the centre of the tibial plateau. Contact pressures / areas were recorded by sensors inserted between the tibia and femur below the menisci. Changes in relative femoral and tibial position in the coronal plane were obtained by an optical tracking system. Results. medial and lateral JLO caused significant tibiofemoral subluxation and pressure distribution changes. Medial (varus) JLO caused the femur to sublux medially down the coronal slope of the tibial plateau, and vice versa for lateral (valgus) downslopes (P=0.01). Areas of peak pressure moved 12 mm and 8 mm across the medial and lateral condyles, onto the ‘downhill’ meniscus and the ‘uphill’ tibial spine. Changes in JLO had only small effects on maximum contact pressures. Conclusion. A change of JLO during load bearing caused significant mediolateral tibiofemoral subluxation. The femur slid down the slope of the tibial plateau to abut the tibial eminence and also to rest on the downhill meniscus. Clinical Relevance. These results provide important information for understanding the consequences of creating coronal JLO and for clinical practice in terms of osteotomy planning regarding the effect on JLO

Objectives. Patient-specific (PS) implantation surgical technology has been introduced in recent years and a gradual increase in the associated number of surgical cases has been observed. PS technology uses a patient’s own geometry in designing a medical device to provide minimal bone resection with improvement in the prosthetic bone coverage. However, whether PS unicompartmental knee arthroplasty (UKA) provides a better biomechanical effect than standard off-the-shelf prostheses for UKA has not yet been determined, and still remains controversial in both biomechanical and clinical fields. Therefore, the aim of this study was to compare the biomechanical effect between PS and standard off-the-shelf prostheses for UKA. Methods. The contact stresses on the polyethylene (PE) insert, articular cartilage and lateral meniscus were evaluated in PS and standard off-the-shelf prostheses for UKA using a validated finite element model. Gait cycle loading was applied to evaluate the biomechanical effect in the PS and standard UKAs. Results. The contact stresses on the PE insert were similar for both the PS and standard UKAs. Compared with the standard UKA, the PS UKA did not show any biomechanical effect on the medial PE insert. However, the contact stresses on the articular cartilage and the meniscus in the lateral compartment following the PS UKA exhibited closer values to the healthy knee joint compared with the standard UKA. Conclusion. The PS UKA provided mechanics closer to those of the normal knee joint. The decreased contact stress on the opposite compartment may reduce the overall risk of progressive osteoarthritis. Cite this article: K-T. Kang, J. Son, D-S. Suh, S. K. Kwon, O-R. Kwon, Y-G. Koh. Patient-specific medial unicompartmental knee arthroplasty has a greater protective effect on articular cartilage in the lateral compartment: A Finite Element Analysis. Bone Joint Res 2018;7:20–27. DOI: 10.1302/2046-3758.71.BJR-2017-0115.R2

Abstract. Introduction. The popularity of all-inside meniscal repair devices has led to a shift away from inside-out meniscus repair without comparative studies to support the change. The aim of this study was to compare the failure rate and time to failure of all-inside and inside-out meniscus repair performed in elite athletes. Methodology. A retrospective review was performed of all elite athletes who underwent meniscal repair, with a minimum of two-year follow-up between 2013 and 2019. Repairs were classified as all-inside or inside-out according to the repair technique. Failure was defined as undergoing a subsequent surgery to address a persistent meniscal tear. Results. 192 (135 lateral and 57 medial) meniscal repairs in elite athletes were included and 41 (21%) failed. Medial meniscus tears repaired with the all-inside technique failed at a significantly higher rate (58%) than medial meniscus tears repaired with the inside-out (23%) or lateral meniscus tears repaired with the all-inside (12%) or inside-out (14%) technique (p<.001). At 1 year following repair, 8% of lateral meniscus repairs had failed regardless of technique. Medial meniscus repairs failed at an approximate rate of 15% for inside-out technique and 42% for all-inside technique. By 2 years, approximately 54% of all-inside medial meniscus repairs had failed and by 5 years over 60% of repairs had failed. Conclusion. All-inside medial meniscal repair led to a higher rate of failure compared to inside-out medial or lateral meniscus repair in elite athletes. Medial meniscus repairs failed at a high rate than lateral meniscal repairs

Abstract. Introduction. High posterior tibial slope (PTS) has been recognised as a risk factor for anterior cruciate ligament rupture and graft failure. This prospective randomised study looked at intra-operative findings of concomitant intra-articular meniscal and chondral injuries during a planned ACL reconstruction. Material and Methods. Prospective data was collected as part of a randomised trial for ACL reconstruction techniques. Intra-operative data was collected and these findings were compared with the PTS measured on plain radiograph by a single person twice through a standardised technique and intra-observer analysis was performed. Results. 49 confirmed ACL rupture patients were in the trial. The average age was 34 (23–66) years and 12 patients were female. 17 patients (34%) had PTS of 12 degrees or more. The intra-observer analysis for PTS measurements in a 2-sided paired T test, showed a mean difference of 0.03 degrees with a P value = 0.83. 23 patients had medial meniscal pathology identified, 15 (65%) had a PTS <12 degrees. 16 patients had lateral meniscus pathology and 9 (56%) had a PTS <12 degrees. Chondral damage did not appear significantly different in the two groups (<12 degrees 15% vs >12 degrees 23%). Conclusion. In this sample, a PTS >12 degrees was not associated with a higher incidence of meniscal or chondral damage after a confirmed ACL rupture

Abstract. Introduction. The outcome of revision anterior cruciate ligament reconstruction (ACL-R) is guarded, particularly their return to sports activities. It is important to know the factors affecting the functional outcomes following a revision ACL-R. Methods. We analysed results from 39 patients, who underwent a revision ACL reconstruction by a single surgeon and was followed up over a year. Some of them were treated in 2-stage revision while the rest were single-stage revision, depending upon their size of bone tunnel or osteolysis as assessed by pre-operative CT scan. Result. We analysed data from 39 patients with a mean age of 31 (17–52) and an average follow-up of 3.6 years (2–5 years). The average KOOS quality of life score was 58.94 (±23.02) and the mean Lysholm score was 89.48 (±10.1). Medial meniscal tear was significantly correlated with Lysholm score (p<0.005), but not with KOOS-QOL. Tear in lateral meniscus was not related significantly. Patients having Grade II or above cartilage damage showed inferior outcomes in terms of Lysholm score and poor return to sports, and it was statistically significant (p<0.02). There was no significant differences in outcomes between single stage revision and 2-stage revision (p=0.336). 15 patients (42.5%) returned to their pre-injury sports activities after revision surgery with the mean return to sports score of 58.65 (±16.1). Conclusions. The long-term functional outcome after revision ACL reconstruction is satisfactory, but not the return to sports. Expectations on outcome should be carefully managed particularly those having concomitant medial meniscal injury or cartilage damage

Abstract. Introduction. Elite athletes sustaining a graft re-rupture after ACL reconstruction (ACL-R) undergo revision reconstruction to enable their return to elite sport. The aim of this study was to determine the rate of return to play (RTP) and competition levels at 2 and 5 years post revision ACL-R. Methodology. A consecutive series of revision ACL-R in elite athletes undertaken by the senior author between 2009 and 2019 was retrospectively reviewed. Outcome measures were RTP rates and competition level. Results. Forty-nine athletes underwent revision ACL-R and were included. 87.8% returned to elite sport of which 75.5% were at the same level. At 2 years post-surgery, 79.6% were still playing, 51% at the same level; and at 5 years 44.4% were still playing, 20% at the same level. Athletes with > 50% thickness chondral lesions were less likely to RTP (66.7% vs 94.6%, p = 0.026) and maintain the same competition level (50% vs 83.8%, p = 0.047). Those with medial meniscus pathology were less likely to RTP at the pre-injury level (64.5% vs 94.4%, p = 0.036). Median career length after revision ACL-R was 73 months (95% CI, 43.4 to 102.6), 23 months at the same level (95% CI, 13.6 to 32.4). The probability of still playing at 5 years post-surgery was 55.9% with 22.5% chance of maintaining pre-injury competition level. Conclusion. RTP rates and competition level of elite athletes decreased over time after revision ACL-R. Chondral pathology of > 50% thickness were associated with lower RTP rates and competition levels

The role of arthroscopy in the treatment of soft-tissue injuries associated with proximal tibial fractures remains debatable. Our hypothesis was that MRI over-diagnoses clinically relevant associated soft-tissue injuries. This prospective study involved 50 consecutive patients who underwent surgical treatment for a split-depression fracture of the lateral tibial condyle (AO/OTA type B3.1). The mean age of patients was 50 years (23 to 86) and 27 (54%) were female. All patients had MRI and arthroscopy. Arthroscopy identified 12 tears of the lateral meniscus, including eight bucket-handle tears that were sutured and four that were resected, as well as six tears of the medial meniscus, of which five were resected. Lateral meniscal injuries were diagnosed on MRI in four of 12 patients, yielding an overall sensitivity of 33% (95% confidence interval (CI) 11 to 65). Specificity was 76% (95% CI 59 to 88), with nine tears diagnosed among 38 menisci that did not contain a tear. MRI identified medial meniscal injuries in four of six patients, yielding an overall sensitivity of 67% (95% CI 24 to 94). Specificity was 66% (95% CI 50 to 79), with 15 tears diagnosed in 44 menisci that did not contain tears. MRI appears to offer only a marginal benefit as the specificity and sensitivity for diagnosing meniscal injuries are poor in patients with a fracture. There were fewer arthroscopically-confirmed associated lesions than reported previously in MRI studies. Cite this article: Bone Joint J 2014;96-B:1631–6

We present the first study in vivo of meniscal movement in normal knees under load. Using an open MR scanner, allowing imaging in physiological positions in near to real-time, 16 young footballers were scanned moving from full extension to 90° flexion in the sagittal and coronal planes. Excursion of the meniscal horns, radial displacement and meniscal height were measured. On weight-bearing, the anterior horn of the medial meniscus moves through a mean of 7.1 mm and the posterior horn through 3.9 mm, with 3.6 mm of mediolateral radial displacement. The height of the anterior horn increases by 2.6 mm and that of the posterior horn by 2.0 mm. The anterior horn of the lateral meniscus moves 9.5 mm and the posterior horn 5.6 mm, with 3.7 mm of radial displacement. The height of the anterior horn increases by 4.0 mm, and that of the posterior horn by 2.4 mm. In non-weight-bearing, the anterior horn of the medial meniscus moves 5.4 mm and the posterior horn 3.8 mm, with 3.3 mm of radial displacement. The anterior horn of the lateral meniscus moves 6.3 mm, and the posterior horn 4.0 mm, with 3.4 mm of radial displacement. The most significant differences between weight-bearing and non-weight-bearing were the movement and vertical height of the anterior horn of the lateral meniscus

Aims

The antidiabetic agent metformin inhibits fibrosis in various organs. This study aims to elucidate the effects of hyperglycaemia and metformin on knee joint capsule fibrosis in mice.