An unusual case of chondrolysis of the hip: a possible etiology for a rare condition - a case report.

UNLABELLED: Idiopathic chondrolysis of the hip (ICH) is a rare condition of unknown etiology, and is characterized by rapid, progressive destruction of the articular cartilage in the coxofemoral joint. This condition has an insidious onset, and is observed more commonly in female preadolescents. Patients report intense pain, motion restriction, and often present with an antalgic gait. Medical imaging techniques are required to make a differential diagnosis and biological markers for inflammation and infection should be evaluated. Avascular necrosis, septic arthritis, and juvenile idiopathic arthritis are the primary alternatives that should be precluded before making a diagnosis. Conservative treatment focuses on pain control and preservation of joint mobility. However, surgical treatment may be an option for these patients. We present a rare case of a 10-year-old boy where imaging tests and physical examination were consistent with conventional idiopathic hip chondrolysis. Following hip joint biopsy and culture, we observed the presence of bacteria originating from the mouth, which could have been responsible for the pathogenesis of ICH. This is the first report of ICH in which common bacteria of the mouth were found upon joint biopsy. In addition, with respect to the pathogenesis of hip chondrolysis, this case emphasizes that numerous factors are involved, many of which remain unknown.

LEVEL OF EVIDENCE: V.