Partial Capitate Shortening Osteotomy and Its Impact on Lunate Revascularization: Mid-Term Results

A novel capitate bone Ilizarov external fixator for treating Kienböck's disease: an anatomical and biomechanical study

This study aims to measure anatomical data of the capitate bone, develop an external fixator for treating late-stage osteonecrosis of lunate through Ilizarov technique, and evaluate its biomechanical performance. We selected eight wrist joint specimens to measure various parameters of the capitate bone, including its length, the distance from the junction of capitate head and body to the proximal end, as well as the width of its proximal head and distal body. Additionally, we measured these same indicators in 107 patients who had undergone wrist X-ray examination. Based on our measurements, we categorized the capitate bone into two groups and designed two types of capitate bone Ilizarov external fixator (CIEF) for it. Then, we compared it with the orthofix external fixator (OEF) through dynamic fatigue biomechanical experiments and pull-out resistance experiments. The results of the measurement revealed two categories of general patterns in the capitate bone. The first type maintains a consistent longitudinal axis between the proximal and distal ends. The second type is characterized by its proximal end being close to the radial side and its distal end being close to the ulnar side. In the dynamic tensile fatigue test, CIEF-A and CIEF-B had smaller maximum displacement values compared to the OEF (P < 0.05). In the anti-pull-out experiment, both CIEF-A and CIEF-B exhibited higher maximum pull-out force than the OEF (P < 0.05). CIFE is a treatment for advanced osteonecrosis of the lunate bone. It is specifically designed to align with the anatomical characteristics of the capitate bone, providing excellent biomechanical properties and a simple clinical procedure. However, additional clinical experiments are needed to confirm its effectiveness in the future.

Functional and radiological results of partial capitate shortening osteotomy in the treatment of Kienböck's disease

This study assessed the functional and radiological results of partial capitate shortening osteotomy in the treatment of Lichtman stage 2 and 3A Kienböck's disease. Nineteen patients who underwent partial capitate shortening osteotomy between 2014 and 2017 were included. Functional and radiological parameters were assessed both pre- and postoperatively. The mean age was 35 years and the mean follow-up was 16 months. Pain scores, wrist range of motion, hand and finger strength, carpal height ratio and lunate height were significantly improved compared with their preoperative values. Sixteen patients were able to return to work. Ten of them had complete and six had partial revascularization. The mean time taken to return to work was 62 days. No vascularity was achieved in three patients who were unable to return to work. Partial capitate shortening osteotomy is effective in the treatment of stage 2 and 3A Kienböck's disease with successful results both functionally and radiologically. Level of evidence: IV.