Aims. Treatment of high-grade limb bone sarcoma that invades a joint requires en bloc extra-articular excision. MRI can demonstrate joint invasion but is frequently inconclusive, and its predictive value is unknown. We evaluated the diagnostic accuracy of direct and indirect radiological signs of intra-articular tumour extension and the performance characteristics of MRI findings of intra-articular tumour extension. Methods. We performed a retrospective case-control study of patients who underwent extra-articular excision for sarcoma of the knee, hip, or shoulder from 1 June 2000 to 1 November 2020. Radiologists blinded to the pathology results evaluated preoperative MRI for three direct signs of joint invasion (capsular disruption, cortical breach, cartilage invasion) and indirect signs (e.g. joint effusion, synovial thickening). The discriminatory ability of MRI to detect intra-articular tumour extension was determined by receiver operating characteristic analysis. Results. Overall, 49 patients underwent extra-articular excision. The area under the curve (AUC) ranged from 0.65 to 0.76 for direct signs of joint invasion, and was 0.83 for all three combined. In all, 26 patients had only one to two direct signs of invasion, representing an equivocal result. In these patients, the AUC was 0.63 for joint effusion and 0.85 for synovial thickening. When direct signs and synovial thickening were combined, the AUC was 0.89. Conclusion. MRI provides excellent discrimination for determining intra-articular tumour extension when multiple direct signs of invasion are present. When MRI results are equivocal, assessment of synovial thickening increases MRI’s discriminatory ability to predict intra-articular joint extension. These results should be interpreted in the context of the study’s limitations. The inclusion of only extra-articular excisions enriched the sample for true positive cases. Direct signs likely varied with tumour histology and location. A larger, prospective study of periarticular bone sarcomas with spatial correlation of histological and radiological findings is needed to validate these results before their adoption in clinical practice. Cite this article: Bone Jt Open 2024;5(10):944–952

Aims

Pellino1 (Peli1) has been reported to regulate various inflammatory diseases. This study aims to explore the role of Peli1 in the occurrence and development of osteoarthritis (OA), so as to find new targets for the treatment of OA.

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.

Introduction. Most of the algorithm available today to balance varus knee is based on a surgeon's hands-on experience without full understanding of pathological anatomy of varus knee. The high-resolution MRI allows us to recognize the anatomical details of the posteromedial corner and the changes of the soft tissue associated with the osteoarthritis and varus deformity. We have in this study, reviewed 60 cases of severe varus knee scheduled for TKR and compared it to normal MRI and those MRI were evaluated and read by a musculoskeletal radiologist. We have documented clearly the changes that happens in soft tissue, leading to tight medial compartment. We will also show multiple short intra-operative video confirming that MRI findings. Material & method. We have retrospectively reviewed the MRI on 60 patients with advanced osteoarthritis varus knee. We also reviewed 20 MRI for a normal knee matched for age. We evaluated the posteromedial complex and MCL in sagittal PD-weighted VISTA to check the alignment of the MCL and posteromedial complex and the associate MCL bowing and deformity that could happen in osteoarthritis knee. We have measured the thickness of the posteromedial complex and the posterior medial bowing of the superficial MCL and the involvement of the posterior oblique ligament in those patients. To measure the posterior bowing of the MCL, a line was drawn through the posterior aspect of both menisci and we measured the distance between the posterior edge of MCL to that line in actual image. To measure the thickness of the posteromedial complex, we measured it at two areas in the posterior medial corner posteriorly at the level of the medial meniscus. Measuring the medial bowing of the MCL was done by a line drawn through the medial edge of the femoral condyle and the tibial condyle at the level of the medial meniscus to the inner aspect of the MCL. The normal distance between the posterior aspects of the MCL to the posterior meniscus line was approximately measured 2 cm. in average. Results. We were able to recognize and measure the medial deviation of MCL in all arthritic knees due to the deformity and the effect of the medial margin osteophyte and medial extrusion of the meniscus. Thickening of posteromedial complex was recognized in the majority of the cases with prominent thickening seen in 50/60 knees with average thickness measuring approximately 1.2 cm due to the synovial thickening, adhesions, granulation tissue, degenerated medial meniscus, and involvement of the posterior oblique ligament and the capsular branch of the semimembranosus tendon, as well as the oblique popliteal ligament. The involvement of posterior oblique ligament were seen in majority of the cases. In 55 cases we have showed a heterogeneous appearance of the ligament and loss of normal signal within the postero medial complex and we have documented that the oblique ligament will cause the posterior bowing of the MCL. The medial bowing of the MCL is also correlated to the severity of the varus deformity with an average distance to the normal medial line of the medial meniscus measuring approximately 1.1 cm. Discussion. Our study shows that the changes affecting the superficial MCL is likely to be secondary to the obvious changes involving the posteromedial complex and to the marginal osteophyte as well as the extrusion of the medial meniscus. Also, we have confirmed that there are deforming structures such as the oblique ligament with adhesion and thickening with all the posterior medial complex. Those changes clearly caused the posterior bowing to the superficial MCL without an actual shortening of the ligament. The scarring tissue in the posteromedial corner and the adhesion is acting as a soft phyte tensioning and deforming the ligament and the posterior capsule. The oblique ligament act as a deforming forces forcing the superficial MCL to bow posteriorly. The lengths of the superficial MCL stayed the same. Conclusion. The conventional wisdom of releasing the distal attachment of the superficial medial MCL to balance knee has to be a challenge based on our MRI finding. Releasing the superficial MCL can sometimes lead to a major instability of the knee requiring a more constrained implant. Our MRI assessment clearly showed that the Superficial MCL is deformed because of posterior bowing and medial bowing and considerable thickening of the posteromedial corner, as well as the accompanying osteophyte. We believe that clearing the superficial MCL and excising those thickened scar tissue in the posterior medial corner will enable us to balance the knee without creating instability Conclusion: The conventional wisdom of releasing the distal attachment of the superficial medial MCL to balance knee has to be a challenge based on our MRI finding. Releasing the superficial MCL can sometimes lead to a major instability of the knee requiring a more constrained implant. Our MRI assessment clearly showed that the Superficial MCL is deformed because of posterior bowing and medial bowing and considerable thickening of the posteromedial corner, as well as the accompanying osteophyte. We believe that clearing the superficial MCL and excising those thickened scar tissue in the posterior medial corner will enable us to balance the knee without creating instability

Total knee arthroplasty (TKA) is a common orthopaedic procedure with over 1,500 done in 2016 in Ireland alone. 96% of all TKAs are due to pain in the knee associated with osteoarthritis. According to the UK National Joint Registry (NJR), there is a 0.47%, 1.81%, 2.63% and 4.34% probability risk of undergoing a revision TKA within one, three, five and ten years respectively post-index surgery. A variety of reasons for failure of TKA have been described in the literature including infection, aseptic loosening, pain, instability, implant wear, mal-alignment, osteolysis, dislocation, peri-prosthetic fracture and implant fracture. The NexGen Posterior Stabilised Fixed has NJR revision rates of 0.44%, 1.61% and 2.54% at years one, three and five respectively. A retrospective review was carried out of 350 NexGen TKAs that were performed directly by, or under the supervision of, a fellowship trained arthroplasty surgeon in a dedicated orthopaedic hospital between April 2013 and December 2015. 26 (7.4%) of these were revised as of 31 December 2017. Three were for septic arthritis with the remaining 23 (6.6%) for aseptic loosening. Patients typically started to experience symptoms of medial tibial pain with supra-patellar swelling from a combination of effusion and synovial thickening at 12–24 months. Inflammatory markers were normal in all cases. Radiographs of symptomatic knee replacements showed bone loss on the medial tibia with a tilt of the tibial component into a varus alignment. The high number of revisions of this particular prosthetic has led to its use being discontinued at this centre

Introduction. Osteoarthritis (OA) of the knee, a prevalently degenerative joint disorder provoked by articular cartilage loss, accounts for the leading cause of total knee arthroplasty. Autophagy is an indispensable intracellular event that maintains chondrocyte survival and metabolism. MicroRNAs are non-coding small RNAs participating in tissue morphogenesis, remodeling, and homeostasis. This study was undertaken to investigate the effect of microRNA-128 (miR-128) knockdown on the development of OA knees. Materials/Methods. Knee joints in rats were subjected to anterior cruciate ligament transection (ACLT) for inducing OA. Articular cartilage, synovium, and subchondral bone microarchitecture were assessed by OARSI scoring system, histomorphometry, and μCT imaging. Chondrocyte autophagy in terms of the expression of autophagic markers Atg4, Atg12, microtubule-associated protein 1 light chain 3 (LC3), and autophagosome formation was verified. Expression of microRNA, mRNA and signaling transduction were quantified with in situ hybridization, RT- quantitative PCR, and immunoblotting. Results. Chondrocytes in the affected knees showed weak expression of autophagic markers Atg4, Atg12, and LC3-II abundances in conjunction with significant increases in OARSI scores and a 2.5-fold elevation in miR-128 expression. The gain of miR-128 signaling in intact joints through intra-articular injection of miR-128 precursor resulted in 1.8–2.1-fold elevations in serum cartilage breakdown products CTX-II and COMP concentrations. miR-128 overexpression caused the joints to show evident chondrocyte apoptosis as evidenced by TUNEL staining concomitant with severe cartilage damage. Of note, antisense oligonucleotide knockdown of miR-128 (miR-128-AS) enabled the affected knee joints to show minor responses to the ACLT escalation of autophagy dysfunction in chondrocytes, cartilage breakdown histopathology, and OARSI scores. Administration with miR-128-AS also attenuated the ACLT-induced synovial membrane thickening, hyper-angiogenesis, and hypercellularity, which subsequently alleviated osteophyte accumulation, subchondral plate destruction, and trabecular microstructure loss. Conclusion. miR-128 signaling impairs chondrocyte autophagy, which ramps up chondrocyte apoptosis and OA knee development. This study highlights an emerging miR-128 knockdown strategy that sustains cartilage microarchitecture integrity and thereby delays OA knee pathogenesis

Objectives

The purpose of this study was to compare the thickness of the hip capsule in patients with surgical hip disease, either with cam-femoroacetabular impingement (FAI) or non-FAI hip pathology, with that of asymptomatic control hips.

Introduction: Pain and mass lesions around hip resurfacing are reported with increasing frequency. The aetiology is unknown but reaction to metal wear debris and mechanical impingement have both been suggested. We are aware of a group of our patients with significant pain following resurfacing. We sought to correlate metal ion levels with X-ray findings and any local soft tissue reaction around the prosthesis. Methods: Patients with significant groin pain following hip resurfacing were identified from routine clinics. Blood was tested for cobalt and chromium levels using inductively coupled mass spectrometry in all patients. Cup abduction angle and femoral stem version were estimated from plain radiographs. Patients underwent ultrasound scan (USS) of the affected hip joint. Bilateral prostheses were excluded to avoid confounding. Results: 47 unilateral painful hip resurfacings (24 female) were identified. USS was performed in 42 patients and was abnormal in 25 (15 female). Abnormalities ranged from simple joint effusion with or without synovial thickening, through to cystic masses in the posterior joint and solid masses related to the ileopsoas tendon similar to the appearances previously described in pseudotumours. A two sample t-test demonstrated cobalt and chromium ion levels were significantly higher in patients with abnormalities on USS (p=0.038, p=0.05 respectively), patients with normal USS were more likely to have a retroverted femoral component (p=0.01). Discussion: We describe two groups of patients with a painful hip resurfacing: those with raised metal ions and local soft tissue reaction, and those with lower metal ions and no soft tissue reaction. The retroverted stems in the second group could cause an iatrogenic cam-type impingement. Metal ion levels are useful to guide further imaging. Raised levels should prompt investigation for a soft tissue abnormality with either USS or MRI, lower levels suggest investigation should look for mechanical impingement with imaging such as CT

Purpose: Pigmented Villonodular Synovitis (PVNS) is an uncommon presentation characterised by hyperplastic synovium, bloody effusions and bone erosions. Incompletely resected localised and diffuse lesions have a high recurrence rate. The management of recurrent lesions depends on the expertise of the surgeon and severity of the lesion. The imaging characteristics of PVNS and experience of British knee surgeons in managing these lesions is presented in our study. Methods: A postal questionnaire was sent to 100 knee surgeons of the British Association of Surgeons of the Knee (BASK) with questions relating to their experience in managing localised and recurrent PVNS. The options included either arthroscopic or open synovectomy with or without radiotherapy, radical excision or referral. Results: 74 responses were included in the study. 73 out of the total cohort of 74 surgeons (98.7%) had seen less than 5 presentations in their career. Localised lesions were treated primarily by arthroscopic synovectomy [N=58(78.4%)] or open synovectomy [N=12(16.2%)] with radiotherapy being utilised in 4 lesions (5.4%). For local recurrence the management was arthroscopic [N=26(35.1%)] and open [N= 19(25.7%)] synovectomy. Radiotherapy was used in 18 (24.3%) of patients with localised recurrence and 8 (10.8%) of were referred to specialist units. Infiltrating lesions were treated with open synovectomy and radiotherapy [N=22(29.7%)] and 20 cases [27.02%] were referred to specialist units. Imaging of PVNS and Conclusions: The role of imaging is invaluable in early diagnosis and treatment due to limited experience in managing such presentations. Routine radiography and Computerised Axial Tomography (CT scan) often demonstrate non-marginal pressure erosions with sclerotic margins as well as nodular soft tissue masses. Sonography shows non-specific focal or nodular synovial thickening with increased flow on colour doppler. Magnetic Resonance imaging characteristics of PVNS are nodular, synovial masses which are low signal on T1-weighted and T2-weighted imaging

With medial unicompartmental osteoarthritis (OA) there is occasionally a full-thickness ulcer of the cartilage on the medial side of the lateral femoral condyle. It is not clear whether this should be considered a contraindication to unicompartmental knee replacement (UKR). The aim of this study was to determine why these ulcers occur, and whether they compromise the outcome of UKR.

Case studies of knees with medial OA suggest that cartilage lesions on the medial side of the lateral condyle are caused by impingement on the lateral tibial spine as a result of the varus deformity and tibial subluxation. Following UKR the varus and the subluxation are corrected, so that impingement is prevented and the damaged part of the lateral femoral condyle is not transmitting load. An illustrative case report is presented.

Out of 769 knees with OA of the medial compartment treated with the Oxford UKR, 59 (7.7%) had partial-thickness cartilage loss and 20 (2.6%) had a full-thickness cartilage deficit on the medial side of the lateral condyle. The mean Oxford Knee Score (OKS) at the last follow-up at a mean of four years was 41.9 (13 to 48) in those with partial-thickness cartilage loss and 41.0 (20 to 48) in those with full-thickness loss. In those with normal or superficially damaged cartilage the mean was 39.5 (5 to 48) and 39.7 (8 to 48), respectively. There were no statistically significant differences between the pre-operative OKS, the final review OKS or of change in the score in the various groups.

We conclude that in medial compartment OA, damage to the medial side of the lateral femoral condyle is caused by impingement on the tibial spine and should not be considered a contraindication to an Oxford UKR, even if there is extensive full-thickness ulceration of the cartilage.

Four patients who developed malignant synovial tumours are described; one with chondromatosis developed a synovial chondrosarcoma and three with pigmented villonodular synovitis developed malignant change. The relevant literature is discussed.

A 12 year old girl presented with a history of intermittent pain in her left knee since she started walking. She was seen in the vascular clinic due to engorged veins in her left leg and was diagnosis of Klippel-Trenaunay syndrome was made. Her knee pain worsened and an orthopaedic opinion was obtained. A history of repeated knee effusion and swelling was noted. Examination revealed partial gigantism of the left leg and reduced range of motion of the knee. There was soft tissue swelling of the knee with no effusion. Blood investigations were normal. X-rays showed an arthritic joint. MRI scans revealed synovial thickening and a vascular malformation suggesting a synovial haemangioma. She underwent Radical Open Synovectomy and excision of the haemangioma. Blood loss was minimal. Extensive haemosiderin deposition was noted along with Grade IV arthritic changes. Postoperative recovery was uneventful. Surgeons have been reluctant to excise synovial hemangiomas due to the risk of haemorrhage. A recent paper from Switzerland suggested excision was possible with minimal blood loss. Haemosiderin deposition due to recurrent haemarthrosis may predispose to articular damage. We recommend early excision of synovial haemangiomas to minimise articular damage

Introduction and Objectives: Approximately 30–50% of injuries to the ankle involve soft tissues. Materials and Methods: Fifty-nine patients diagnosed with anterior capsular entrapment syndrome (ACES) of the ankle were treated using arthroscopic debridement from May 1993 to October 2002. All patients presented with chronic pain and limitation of dorsiflexion after more than 4–6 months of conservative treatment. The study included 34 males and 25 females with an average age of 25 years. The principal cause ACES was one or more forced supinations of the ankle. More than half of the patients participated regularly in sports activities. The study did not include patients with a previous history of ankle surgery, fractures, frank instability, arthrosis, significant cartilaginous lesions (osteochrondritis, osteonecrosis, etc.), arthrofibrosis, or systemic arthritis, patients older than 60 years, and those with less than 6 months of follow-up time. Diagnosis of ACES was generally based on clinical data. The most commonly-used supplemental modalities were ultrasound and MRI. Patients were evaluated using the Ogilvie-Harris scale. Changes in variable values were evaluated using the Wilcoxon test, and the threshold for statistical significance was set at p< 0.05. Results: Patients experienced significant improvements both subjectively (100% would have the same intervention again even though in 2 cases results were only fair) and based on the Ogilvie-Harris scale. Pain and functional limitation showed the greatest improvement, as compared to inflammation, stiffness, or instability. In all cases, differences in pre- and postoperative values were statistically significant (p< 0.05). During arthroscopic surgery, anterior synovial thickening was noted in all cases (lateral, medial and/or central) associated in some cases with osteophytosis and tibiotalar chondromalacia. The main complications were paresthesia and dysesthesia. Average follow-up time was 43 months (6 months – 9 years). Discussion and Conclusions: It may be concluded from our study that in a high percentage of cases of ACES of the ankle without degenerative changes or significant instability, good results are achieved with arthroscopic surgery

Thirty-nine patients underwent reconstruction of the anterior cruciate ligament with carbon-fibre and a MacIntosh repair; all had a negative pivot shift test after operation. Some patients had persistent pain, mild effusion and synovial thickening; in 10 of these patients the symptoms warranted arthroscopic examination and biopsy at a mean of 16.9 months after the repair. Arthroscopy revealed that the carbon-fibre had not induced the formation of a "new ligament" and that the repair was merely covered by a thin, fibrous sheath. Histological investigations confirmed this finding, with only a suggestion of a fibroblastic response to carbon-fibre found in two patients. Particles of carbon-fibre were found scattered through the knees. Synovitis and breakdown of the skin over subcutaneous carbon-fibre complicated treatment. Failure of the carbon-fibre to bond to bone was detected radiographically