Septic arthritis of the hip joint in cervical cancer patients after radiotherapy: Three case reports.

Cervical cancer patients may experience hip problems related to the cancer itself or therapeutic management for the cancer. Septic arthritis should be one of the possibilities but there have been no reports on this. Here we present three patients who developed hip problems more than two years after radiotherapy with or without a radical operation. One patient was managed as septic arthritis because of significant inflammatory signs around the affected hip joint even though the causative organism was not confirmed. Succeeding total hip arthroplasty functioned well and had no recurrence of infection. The hip problems of the other two patients were diagnosed as radiation osteonecrosis of the femoral head initially. However, Bacteroides fragilis infection was found several months after total hip arthroplasties. Radiotherapy to the pelvis may damage the hip joint and compromise host-defense mechanisms of the pelvic region. Both factors may increase the possibility of infection of hip joints. Further clinical evidence is needed to understand whether subacute or chronic anaerobic infection could also be one of the causes leading to progressive destruction of the femoral head.