Osteoarthritis is a degenerative joint disease affecting middle-aged and elderly patients. It mainly involves weight-bearing joints such as the hip, knee and spine as well as the basilar joint of the thumb, causing dysfunction and painful symptoms. Often, joint arthritis is accompanied by cartilage defects, joint space narrowing, osteophytes, bone sclerosis and subchondral bone cysts (SBC). The aim of the present study was to explore the pathophysiology responsible for the development of SBCs as well as the association between SBCs and disease progress, the level of clinical symptoms and their impact on postoperative outcomes and risk of possible complications following joint replacements if left untreated. A literature review on PubMed articles was conducted to retrieve and evaluate all available evidence related to the main objective mentioned above. A few theories have been put forth to explain the formation process of SBCs. These involve MMPs secretion, angiogenesis, and enhanced bone turnover as a biological response to abnormal mechanical loads causing repeated injuries on cartilage and subchondral tissue during the development of arthritis. However, the application of novel therapeutics, celecoxib-coated microspheres, local administration of IGF-1 and activated chondrocytes following surgical debridement of SBCs hinders the expansion of SBCs and prevents the progression of osteoarthritis.

Neurofibromatosis type 1 (NF1), which is the most common phacomatoses, is an autosomal dominant disorder characterized by clinical presentations in various tissues and organs, such as the skin, eyes and nervous and skeletal systems. The musculoskeletal implications of NF1 include a variety of deformities, including scoliosis, kyphoscoliosis, spondylolistheses, congenital bony bowing, pseudarthrosis and bone dysplasia. Scoliosis is the most common skeletal problem, affecting 10–30% of NF1 patients. Although the pathophysiology of spinal deformities has not been elucidated yet, defects in bone metabolism have been implicated in the progression of scoliotic curves. Measurements of Bone Mineral Density (BMD) in the lumbar spine by using dual energy absorptiometry (DXA) and quantitative computer tomography (QCT) have demonstrated a marked reduction in Z-score and osteoporosis. Additionally, serum bone metabolic markers, such as vitamin D, calcium, phosphorus, osteocalcin and alkaline phosphatase, have been found to be abnormal. Intraoperative and histological vertebral analysis confirmed that alterations of the trabecular microarchitecture are associated with inadequate bone turnover, indicating generalized bone metabolic defects. At the molecular level, loss of function of neurofibromin dysregulates Ras and Transforming Growth factor-β1 (TGF-β1) signaling and leads to altered osteoclastic proliferation, osteoblastic activity and collagen production. Correlation between clinical characteristics and molecular pathways may provide targets for novel therapeutic approaches in NF1.

Background: Failure of closed manipulative reduction of an acute anterior shoulder dislocation is seldom reported in the literature and is usually due to structural blocks such as soft tissue entrapment (biceps, subscapularis, labrum), bony fragments (glenoid, greater tuberosity) and severe head impaction (Hill-Sachs lesion). Case report: We present a case of an irreducible anterior shoulder dislocation in a 57-year-old male patient after a road-traffic accident. He had severe impaction of the head underneath glenoid rim and associated fracture of the greater tuberosity. Closed reduction performed in the emergency room under sedation and later at the theatre under general anaesthesia was unsuccessful. Open reduction using the dectopectoral approach revealed that the reason for obstruction was the posterolateral entrapment of the biceps tendon between the humeral head and the tuberosity fragment. Reduction was achieved after subscapularis tenotomy and opening of the joint; the tuberosity fragment was fixed with transosseous sutures and the long head of the biceps tendon was tenodesized. The patient had an uneventful postoperative recovery and at his last follow up, 12 months postoperatively, he had a stable joint, full range of motion and a Constant score of 90. Conclusion: A comprehensive literature review revealed 22 similar reports affecting a total of 30 patients. Interposition of the LHBT alone or in combination with greater tuberosity fracture was the most common obstacle to reduction, followed by subscapularis tendon interposition and other less common reasons. Early surgical intervention with open reduction and confrontation of associated injuries is mandatory for a successful outcome.

Background: Solitary fractures of the body of the hamate are rare. Their diagnosis is difficult and requires a high clinical suspicion and a proper radiological examination. Case report: We present a case of a 36-year-old male patient who sustained an intraarticular fracture of the body of the hamate along with dorsal dislocation of the 4^th and 5^th metacarpals on his right dominant hand. Through a dorsal surgical approach, he underwent ORIF of the hamate with screws and stabilization of the dislocated 4^th and 5^th metacarpals with KW. At his last follow-up appointment, 18 months postoperatively, he had no pain, almost full range of motion on his fingers and a Mayo Wrist score of 90 points. Conclusions: Hamate fractures are rare entities that can cause significant patient morbidity if not recognized and treated appropriately.