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Purpose: The purpose of this study was to evaluate the biomechanical effect of core decompression of the distal radius for the treatment of Kienböck's disease., Methods: In 7 fresh cadaver upper extremities, axial loads were applied and the pressure in the radiocarpal joint measured using pressure-sensitive film before and after core decompression of the distal radius., Results: Biomechanically, the stiffness of the distal forearm statistically decreased significantly from 229.4 N/mm to 198.6 N/mm after core decompression. No or minimal changes in the distribution of the force in each radiocarpal fossa and ulnocarpal fossa, the area of contact in each fossa, and the location of the centroid of force were observed., Conclusions: Core decompression of the distal radius in the setting of Kienböck's disease has been documented good clinical outcomes, yet the biomechanical analysis of this surgical technique does not demonstrate obvious unloading of the lunate.

The role of the dorsal radiocarpal wrist ligament has been the subject of several investigations. Several biomechanical studies have used sensors inserted dorsally into the wrist joint to evaluate its pressure distribution. The purpose of this study was to evaluate whether a dorsal capsulotomy that sections the dorsal radiocarpal ligament or insertion of a flexible pressure sensor alters scaphoid or lunate kinematics. Eight cadaver upper extremities were instrumented with motion sensors and placed in a wrist joint simulator. Each arm was moved through continual cycles of wrist flexion/extension and radial/ulnar deviation. Motion data were obtained in the intact state, after a capsulotomy, and after insertion of the sensor. We found that either a dorsal capsulotomy sectioning the dorsal radiocarpal ligament or insertion of the pressure sensor alters scaphoid and lunate kinematics during dynamic wrist motion. This study supports the clinical belief that this dorsal wrist ligament should be spared during surgical approaches to the carpus.

The ulnar styloid (US) architecture was examined radiologically and directly by dissection in 13 cadaver wrists to examine a potential relationship between US shape and US abutment syndrome and to determine an optimal radiographic view that could be used to detect US fractures. A higher incidence of US abutment syndrome in the radially deviated US type was observed by dissection. Radiographs taken at varying shoulder abduction angles suggested that the base of the US and ulnar head are not round. To best evaluate the fovea and the US for possible US fractures, radiographs should be taken with the glenohumeral joint abducted 45 degrees, the elbow flexed 90 degrees, the forearm in neutral rotation, and the x-ray beam directed through the wrist perpendicular to the floor.