Postinfectious heterotopic ossification of the ilium involving the iliacus muscle

Abstract

Heterotopic ossification in soft tissue or muscle is rare in the pediatric and adolescent age group. Most cases are associated with musculoskeletal injury and trauma to the central nervous system. Here, we describe an adolescent patient without a history of trauma or lesions in the central nervous system who presented with a painful limp with limited motion of the left hip. Investigations indicated unusually large heterotopic ossification extending from the inner aspect of the ilium down to the anterior part of the hip, highly likely to have developed after an unrecognized periacetabular pyomyositis primarily involving the iliacus muscle. Surgical excision was performed successfully without perioperative complications. No recurrence was detected at the final follow-up.

Osseous Ilio-Trochanteric Bars as an Etiology of Hip Contracture in a Child with Congenital Contractures

“…Heterotopic ossification in muscles or soft tissues has been well described in children, which most frequently occurs after traumatic brain or spinal cord injuries, but also after burns, encephalitis, or infections 10,11 . These etiologies are all acquired, not congenitally occurring as in our patient.…”