Background: Femoral head osteonecrosis as a result of trauma in
adolescents has a poor prognosis as a result of femoral head collapse and
subsequent degenerative change of the hip. There are currently no satisfactory
treatments for adolescents with this condition, although bisphosphonate
therapy has improved the outcome in animal models of osteonecrosis. We
evaluated bisphosphonate therapy for femoral head osteonecrosis following
trauma in adolescents.
Methods: We established a protocol for identifying adolescents with
osteonecrosis of the femoral head with use of bone scans immediately after
surgical treatment of hips at risk for the development of osteonecrosis
following trauma. In a consecutive group of twenty-eight patients with an
unstable slipped capital femoral epiphysis (twenty-two patients), femoral neck
fracture (four), or traumatic hip dislocation (two), seventeen patients with
osteonecrosis were identified. These patients (thirteen boys and four girls
with a mean age of 12.7 years) and their families gave consent for the
patients to receive treatment with intravenous bisphosphonates. The average
duration of the bisphosphonate treatment was 20.3 months (range, seven to
thirty-nine months). All patients were followed clinically and
radiographically for a minimum of two years.
Results: After a mean duration of follow-up of 38.7 months, fourteen
patients were pain-free. Clinically, all seventeen patients had a good or
excellent outcome. On the average, the Harris hip score was 91.2 points, the
Iowa Hip Rating was 92.1 points, and the Global Pediatric Outcomes Data
Collection Instrument (PODCI) score was 91.5 points. According to the
radiographic classification system of Stulberg et al., nine hips were rated as
Class I or II; six, as Class III; and two, as Class IV.
Conclusions: Bisphosphonate therapy may play an adjunctive role in
the treatment of adolescents with osteonecrosis of the femoral head following
trauma.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.