CASE REPORT: STAGE IV HO FOLLOWING TOTAL HIP ARTHROPLASTY
Positive results of a therapeutic scheme that combines RT, NSAIDs and surgical excision.
INDOCAP
Heterotopic ossification (HO) is a well-known complication following total hip arthroplasty (THA), with an average incidence of 30%. HO may limit hip motion and cause intolerable pain. For these symptomatic stages, surgical excision is mandatory, usually combined with prophylaxis of recurrence with non-steroidal anti-inflammatory drugs (NSAIDs) and/or radiotherapy (RT).
A case report of a 70-year-old woman who developed Stage IV HO after undergoing THA for left hip osteoarthritis is presented. Surgical excision of the HO was performed eighteen months after THA, with adjuvant radiotherapy and indomethacin (75 mg/day for six weeks). After two years of follow-up, the patient had a good hip function with no recurrence of HO.
The case illustrates synergistic effects of three different treatment methods (RT, NSAIDs and surgical excision) in treating HO and preventing its recurrence after a THA. There are no widely accepted guidelines for the treatment of HO after THA. Since NSAIDs and RT inhibit the formation of HO in different phases of its pathogenesis, the authors believe it a good option to combine these two techniques with the surgical excision.
Surgical excision is the only method to remove HO once it becomes established.
Inclusion of adjuvant RT to prevent HO formation by inhibiting osteoblast activity.
NSAIDs decrease the inflammatory status around the hip joint, thus decreasing the number of mesenchymal cells that would further differentiate into osteoblasts.