Arthroscopic Management of Elbow Osteoarthritis.

The incidence of osteoarthritis in the general population is low, but it can be seen in manual laborers, throwing athletes, and people dependent on crutches and wheelchairs. Patients often complain of pain at the terminal extents of motion, and imaging shows osteophyte formation at the tips of the coronoid and olecranon processes as well as thickening of the bone between the coronoid and the olecranon fossae. Recent advances in arthroscopic instrumentation and techniques have led to a growing interest in the arthroscopic treatment of elbow osteoarthritis.

Relative Contribution of the Subsheath to Extensor Carpi Ulnaris Tendon Stability: Implications for Surgical Reconstruction and Rehabilitation.

Purpose: To identify the varying contributions of the proximal and distal portions of the subsheath of the extensor carpi ulnaris (ECU) to its stability, evaluate the correlation of ulnar groove depth and ECU subluxation, and observe the effect of forearm and wrist positions on ECU stability.

Methods: Extensor carpi ulnaris tendon position relative to the ulnar groove was measured in 10 human cadaveric specimens with the subsheath intact, partially sectioned (randomized to distal or proximal half), and fully sectioned. Measurements were obtained in 9 positions: forearm supinated, neutral, and pronated and wrist extended, neutral, and flexed.

Attrition or rupture of digital extensor tendons due to carpal boss: report of 2 cases.

We present 2 cases that demonstrate the potential for tendon involvement in the presence of a carpal boss. In the first, a patient presented with tendon rupture without antecedent pain. In the second, pain and tendon irritation prompted magnetic resonance imaging that revealed tendon fraying, which was confirmed at surgery.

Madelung deformity.

Madelung deformity is a rare congenital anomaly of the wrist caused by asymmetric growth at the distal radial physis secondary to a partial ulnar-sided arrest. The deformity is characterized by ulnar and palmar curvature of the distal radius, positive ulnar variance, and proximal subsidence of the lunate. It more commonly occurs in females than males and typically affects both wrists.

ESET histone methyltransferase is essential to hypertrophic differentiation of growth plate chondrocytes and formation of epiphyseal plates.

The ESET (also called SETDB1) protein contains an N-terminal tudor domain that mediates protein-protein interactions and a C-terminal SET domain that catalyzes methylation of histone H3 at lysine 9. We report here that ESET protein is transiently upregulated in prehypertrophic chondrocytes in newborn mice. To investigate the in vivo effects of ESET on chondrocyte differentiation, we generated conditional knockout mice to specifically eliminate the catalytic SET domain of ESET protein only in mesenchymal cells.