Use of a hand-carved silicone-rubber spacer for advanced Kienböck's disease.

We found that the use of a hand-carved silicone-rubber (Silastic) spacer was reasonably effective in relieving symptoms in thirty-six patients with advanced Kienböck's disease, even though there was still some residual postoperative loss of wrist motion and grip strength. Preoperatively all patients had pain and limited motion of the wrist as well as weakness of grip. Roentgenographically all had fragmentation and collapse of the lunate, and 92 per cent had measurable carpal collapse. Most had had symptoms for longer than one year. After removal of the deformed lunate through a dorsal incision, a silicone-rubber spacer was shaped to fit the defect. Patients were followed for an average of fifty-four months. Thirty-two patients were followed for at least two years; all but three were improved. This procedure is not recommended when the shape of the lunate is normal or not significantly altered, or when the lunate has not collapsed as measured by precise determinants.