Idiopathic chondrolysis treated with etanercept

Idiopathic chondrolysis of the hip in children has been well documented in the literature. The insidious nature of the symptoms and lack of early radiographic findings and diagnostic testing often delay diagnosis. Children often report a stiff, painful hip and have an associated limp in the absence of trauma or constitutional symptoms. Despite these symptoms it remains a poorly understood diagnosis with no identifiable cause. Some have speculated an inflammatory cause, as this disease exhibits joint space narrowing, presumably due to enzymatic activity similar to juvenile rheumatoid arthritis. Despite case reports attempting traction, physical therapy, nonsteroidal anti-inflammatories, steroids, and even operative intervention, no current treatment regimen exists that offers proven appreciable benefit. We hypothesized the powerful anti-inflammatory properties of etanercept would provide symptomatic and radiographic improvement of idiopathic chondrolysis of the hip. This article presents a case of an adolescent boy with a stiff, painful left hip that failed treatment with traction, physical therapy, naproxen, and methotrexate, prior to initiating etanercept. After 1 year of daily etanercept therapy, the patient's hip motion improved in all directions and his pain completely resolved. This novel therapeutic approach offered symptomatic relief and radiographic improvement, and may provide an effective treatment strategy for this difficult disease.