Heterotopic ossification in patients with hip osteoarthritis below forty years old after total hip replacement.

BACKGROUND Even though heterotopic ossification (HO) is most often asymptomatic in patients after total hip replacement (THR), it remains a serious problem in orthopaedics as it is observed in nearly all operated patients. MATERIALS AND METHODS The article presents a pre- and post-operative retrospective analysis of heterotopic ossification based on radiographic evidence. The study involved 77 patients below forty years old who underwent THR due to degenerative changes. Heterotopic ossification was evaluated using Brooker's basic four-grade scale. RESULTS Heterotopic ossification was diagnosed more often in women. The study confirmed once again that non-steroidal anti-inflammatory drug (NSAID) prophylaxis reduces the risk of ossification. We propose that the hydroxyapatite coating of implants may also contribute to a higher incidence of heterotopic ossification in operated patients. CONCLUSIONS A history of surgical procedures and a lack of NSAID prophylaxis contributed to heterotopic ossification in the region of the replaced hip joint in the study group.