We performed 41 core decompressions in 32 patients for stage I or stage II osteonecrosis of the femoral head. The intra-osseous pressure at the intertrochanteric level was raised in 28 (68%) and there was histological confirmation of necrosis in 36 hips (88%). After a follow-up of 10 to 84 months (mean 31) nine of the 12 stage I hips (75%) showed significant clinical or radiological deterioration; no evidence of necrosis had been found in the core specimens of the other three hips. Of the 29 hips in stage II, 25 (86%) showed significant radiological deterioration, and only five (17%) had improved clinically. We believe that once necrosis has occurred, core decompression will not significantly influence the subsequent course of the disease.

A white child with a long history of illness from the age of six was thought at first to have Hodgkin's disease. There followed an acute illness with lesions involving glands, lungs, bone and skin. Mycobacterium avium-intracellulare group (Battey) was isolated from various lesions at the age of thirteen. After six years of continuous treatment the patient, now eighteen, is living a normal life.