Prospective Case- Control Study on the Etiopathology of Kienbock Disease

Background: Multiple hypotheses regarding the cause of Kienbock disease have been proposed in seemingly contradictory small case series and cohort studies with inadequate statistical power. A prospective case-control study was conducted to analyze frequently discussed risk and causal factors. Methods: Eighty-one consecutive patients with Kienbock disease and 198 patients with wrist ganglia were referred to the authors' clinic between 1990 and 2012, and 2003 and 2011, respectively. Patients with wrist ganglia were chosen as a control group because of the similar age distribution compared with the general population and because the common etiopathologic features of wrist ganglia and Kienbock disease can be excluded. Demographic, occupational, and medical information, including age, sex, handedness, ethnicity, education, occupation and employment status, prior treatment, and medical history were collected. Associated conditions and medication were assessed at a follow-up examination. Results: Sixty-five of 81 patients with Kienbock disease and 70 of 198 controls were included in the study. Both groups were comparable with respect to age distribution and handedness. Employment status and job characteristics were similar in both groups. Hand-arm vibration during work or leisure activity over a period of 2 years was present in 23 percent with Kienbock disease and in 24 percent of 70 controls. Cortisone was used in six of 65 cases with Kienbock disease [controls, zero of 70] for an average duration of 46 months. Conclusions: Trauma, hand-arm vibration, heavy manual labor, and comorbidities were not associated with Kienbock disease. Steroid-associated Kienbock disease in six of 65 cases is consistent with the findings reported for osteonecrosis of other parts of the skeleton. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.