Avascular necrosis of femoral head associated with connective tissue disease in Nigerians: case series.

BACKGROUND: Avascular Necrosis (AVN) or osteonecrosis has been frequently reported among Nigerians with sickle cell disease. Other known aetiologies include connective tissue diseases, alcohol, fat embolism, juvenile arthritis and pregnancy. Connective tissue disease (CTD) are uncommonly reported among Nigerians.

OBJECTIVE: To report the cases of three Nigerian female patients with radiological evidence of AVN associated with connective tissue diseases and inflammatory arthritis who presented to a rheumatology hospital in Lagos, Nigeria.

METHODS: The first patient was a 36-year-old woman who was initially diagnosed as systemic lupus erythematosus (SLE). After four years of treatment, she presented with intense pain in the left hip, which on radiograph showed AVN. She was initially treated with NSAIDS and narcotic analgesics. She eventually had a left hip replacement. The second patient was a 44-year-old female, who had presented seven years earlier with features of SLE. She had attended the clinic irregularly. She later developed pain in both hips and shortening of left lower limb over the preceding three years. Radiographs confirmed AVN. She was treated with analgesics. The third patient was an 18-year-old female undergraduate who had rheumatoid arthritis (RA) and later developed bilateral hip pain which on radiograph showed bilateral AVN. She was placed on analgesics and then referred for orthopaedic surgery.

CONCLUSION: Osteonecrosis may be associated with connective tissue diseases. A high index of suspicion is needed for the diagnosis, especially in SLE and RA patients with prolonged hip pain not responding to immunosuppressive.