Apophysitis

Apophysitis



The differential diagnosis for hip pain, a common pediatric musculoskeletal complaint, should include septic joint, apophysitis, inflammatory arthritis, slipped capital femoral epiphysis, and Legg–Calvé–Perthes disease. An appropriate first step is to order anteroposterior and frog-leg lateral radiographs to rule out Legg–Calvé–Perthes disease and slipped capital femoral epiphysis, which might require more urgent intervention.

This patient most likely has apophysitis, an overuse injury characterized by irritation, inflammation, and microtrauma at the apophysis. It is the most common cause of hip pain in adolescents and is unique to the skeletally immature. The apophysis is a secondary ossification center and the site of attachment for the muscle tendon. Because it is the weak point in the bone–tendon–muscle chain, it is easily injured with forceful contraction of the muscle (which can cause an avulsion injury) or with repetitive stress (which can cause apophysitis).

The hip and pelvis have multiple apophyses with large muscle attachments. The anterior–superior iliac spine is often injured in sports that involve a lot of running. This patient plays two running sports and has started to have pain during and after play, which indicates that she should rest.

In apophysitis, radiographs may be normal or may show widening of the apophysis. Management should include analgesics, a short period of protection from weight bearing with crutches, and a gradual return to sports after pain-free range of motion is achieved.

An ultrasound of the hip is warranted if the patient has a painful hip, fever, and an ill appearance, raising suspicion for septic arthritis. The absence of fever or pain on the log-roll test makes a hip-joint effusion or a septic joint unlikely in this case.

Ibuprofen and reassurance would be appropriate for a patient experiencing growing pains, but these pains tend to affect the shins, calves, and thighs, not the hips. Furthermore, they seldom occur during the day and do not affect sports performance.

Laboratory evaluation for inflammatory arthritis is not warranted, as the patient has localized tenderness of the bony pelvis, an atypical presentation for juvenile arthritis.