Epidemiological Profile of Femoral Head Osteonecrosis in the North Indian Population

BACKGROUND: There are limited studies on the epidemiology of femoral head osteonecrosis in Indian population. This study was designed to look for the risk factors of osteonecrosis hip and to assess the severity as per radiological staging (Association Research Circulation Osseous [ARCO]) and clinical score (Harris hip score [HHS]). MATERIALS AND METHODS: 249 patients (382 hips) of osteonecrosis femoral head (ONFH) who were evaluated at our center between January 1, 2005, and June 30, 2013, were included in this retrospective study. The details of history, clinical examination, radiological grading, and HHS were entered into a proforma. RESULTS: The mean age was 34.71 years (range 14-70 years) and 70.28% (n=175) patients were between 20 and 40 years. Male to female ratio was 5:1. Bilateral ONFH was observed in 53.41% (n=133) patients. In atraumatic conditions, bilateral involvement was seen in 61.61% (130/211) patients. Steroid administration (37.3%, 93/249) was most commonly observed in the patients followed by idiopathic in 21.3% (53/249) patients, chronic alcohol consumption in 20.1% (50/249) patients, and trauma in 15.3% (38/249) patients. There were 48% (185/382) hips in ARCO Stage 2 followed by 33% (125/382) in Stage 3 and 16% (61/382) in Stage 4. The mean HHS was 80.97 ± 14.35 in unilateral ONFH. The mean HHS was 72.79 ± 14.43 and 80.07 ± 13.52 in more involved hip and in less involved hip, respectively, in bilateral ONFH. The ARCO staging had statistically significant correlation with HHS (Pearson's correlation coefficient r = −0.783, P < 0.01) in unilateral ONFH patients and more severely affected hip in bilateral (Pearson's correlation coefficient r = −0.654, P < 0.01) ONFH, but it did not show any association with less involved hip in bilateral cases. CONCLUSION: ONFH in the North Indian patients is a disease of young individuals with male predominance. Steroid intake is most commonly observed in these patients followed by idiopathic, chronic alcohol consumption, and trauma.