A retrospective study of bacterial arthritis of the hip in twenty-six adults seen in the years 1942 through 1962 was made. Only patients in the original phase of the hip infection were included bacterial arthritis associated with a specific disease such as brucellosis or tuberculosis was not included. Follow-up information was available on all but one patient and bacteriological information was available on all. There appeared to have been a real increase in the incidence of bacterial arthritis of the hip in adults in recent years.

Diagnosis in these adults was often delayed even though symptoms and signs pointed to involvement of the hip by an infectious process. Staphylococcus aureus caused slightly more than 60 per cent of the infections. Roentgenographic signs of capsular distention occurred later than they do in children. One should compare both hips and look for osteoporosis and slight joint narrowing in the earlier stages.

Disability tended to be severe. Only nine of the twenty-six patients were rehabilitated so that they could return to work or to the level of activity they had prior to their illness. Hip function returned to the preinfection range of motion in only 12 per cent of patients.

Surgical treatment in the adult should be aimed at early and adequate drainage of the hip joint followed by further débridement if surgical drainage does not control the infection. The hips that proceeded to bony ankylosis gave the best result in this series, except for a few special instances. Prolonged immobilization in a cast, in the hope that spontaneous ankylosis will occur, is usually fruitless. We were unable to assess the specific effects on healing produced by antimicrobials, but we believe that they may prevent death as well as distant metastatic infections.