Joint contracture (also known as arthrofibrosis) is a fibrotic joint disorder characterized by excessive collagen production to form fibrotic scar tissue and adhesions within joint capsules. This can severely affect day‐to‐day activities and quality of life because of a restricted range of motion in affected joints. The precise pathogenic mechanism underlying joint contractures is not fully understood. Lumican belongs to the class II small leucine‐rich repeat proteoglycan superfamily, which makes up collagen fibrils in the extracellular matrix. Lumican is ubiquitously expressed in the skin, liver, heart, uterus and articular cartilage and has reported roles in cell migration, proliferation, angiogenesis and Toll‐like receptor 4 signaling. Previous research has suggested that lumican is involved in the pathogenesis of several fibrotic diseases. Because joint contracture resembles a fibrotic disease, we aimed to investigate the role of lumican in the development of joint contracture in vitro. Here, we showed that protein levels were up‐regulated in the fibrotic joint capsule versus control. We observed that lumican significantly enhanced the proliferation, migration and fibroblast–myofibroblast transition of synovial fibroblasts. Moreover, lumican led to increased transcription of alpha‐smooth muscle actin, matrix metallopeptidase 9, Collagen I, plasminogen activator inhibitor 1 and transforming growth factor‐β in vitro. Lumican treatment promoted collagen lattice contraction in a dose‐dependent manner as early as 24 h after treatment. Thus, our studies reveal that lumican could promote fibroblast–myofibroblast transition and joint contracture.

Background. To assess the clinical outcomes of central tendon-splitting approach and double row anchor suturing for the treatment of insertional Achilles tendinopathy. Methods. 28 patients (28 feet) diagnosed with insertional Achilles tendinopathy were included in this study. The inclusions were symptom of hindfoot pain around the insertion of the Achilles tendon, radiographic demonstration of calcification, or degeneration of the Achilles tendon, showing no symptom improvement even after standard nonsurgical treatment for more than six months. The X-ray revealed that patients had obvious posterior superior calcaneal exostosis with the possibility of friction with the Achilles tendon or intratendinous calcification. Surgical correction by the central tendon-splitting approach and double row Achilles tendon suturing was performed. The ankles were immobilized with plaster for four weeks postoperatively. The American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue score (VAS) were assessed preoperatively and at 2 years postoperatively. At final follow-up, the Manchester-Oxford Foot Questionnaire (MOXFQ) as patient-reported outcome measures (PROMs) was also evaluated. Results. No complication, including postoperative wound infection and tendon rupture, was not found. All the patients resumed their daily activities with no high level of daily activities, such as jumping and jogging after 6 weeks postoperatively. 27 patients were available for follow-up for at least 2 years, while only one patient was lost to follow-up. At postoperative 2 years, the postoperative AOFAS score increased significantly, while the VAS score decreased statistically when compared with preoperative values. At final follow-up, 24 patients had complete alleviation of pain, whereas the remaining 3 patients complained of mild heel pain after walking for a long time. The MOXFQ score showed obvious relief of previous symptoms for all included cases. Conclusions. Central tendon-splitting approach and double row Achilles tendon suture provide excellent intraoperative visual field, larger tendon-bone contact area, and stronger pullout strength and, thus, facilitate early rehabilitation. It can be a safe and effective method for the treatment of insertional Achilles tendinopathy.

Hip arthroscopy is an effective method for the diagnosis and treatment of hip joint pathologies. However, gaining access to the central and peripheral compartments is challenging. The present study aimed to assess the advantages of using an arthroscopic extra‑capsular approach and partial capsulotomy for access and subsequent management of hip diseases. Patients subjected to hip arthroscopy by partial capsulotomy for exposure and treatment of hip diseases between February 2012 and February 2016 were retrospectively analyzed. A total of 32 patients, including 19 males and 13 females, aged 19‑48 years (median age, 36 years), had undergone the procedure. Firstly, the distal anterior lateral and anterolateral arthroscopic approach with blunt dissection was performed. Subsequently, a T‑shaped partial capsulotomy was established to achieve adequate exposure. The shaver, radiofrequency probe and tissue penetrating suture grasper were then inserted to perform procedures including debridement of the synovium, suturing of the glenoid labrum. During surgery, a probe hook was used to push the capsule section limbs or pull the sutures placed on the capsule section limbs to improve exposure. For patients with pre‑operative anterior instability, ligamentous laxity or acetabular dysplasia capsules were sutured to finish capsule closure. The pre‑operative and post‑operative Visual Analogue Scale (VAS) score and modified Harris hip score (MHHS) were used to assess the effectiveness of the procedure. No obvious post‑operative complications were encountered. The mean follow‑up time was 22.4 months (range, 18‑32 months) and 31 patients completed the follow‑up, while 1 patient was lost to follow‑up. Compared with the pre‑operative score, the MHHS was significantly increased (66.2±6.0 vs. 82.6±5.2; P<0.05) and the VAS score was significantly decreased (6.5±1.1 vs. 1.2±0.7; P<0.05) at the end of the follow‑up. In conclusion, arthroscopic partial capsulotomy provides access to the peripheral and central compartments of the hip and is a relatively simple technique that is easy to master for surgeons with limited experience in hip surgery.