13-Year-Old Soccer Player With Acute Anterior Hip Pain and a Prior Limp
A 13-year-old competitive soccer player is brought in the day after a tournament, having felt a sudden pop and sharp pain in the right anterior hip while taking a long-range shot. He is antalgic and cannot run. His coach mentions that for about 3 weeks he has had vague right groin aching and a mild limp after training that he did not report. He is afebrile, has no night pain, and has no history of trauma other than kicking.
Examination: he walks with a shortened stance on the right; tenderness is maximal over the anterior inferior iliac spine, with pain on resisted hip flexion and on a straight-leg raise. Hip rotation is full but uncomfortable at end range in flexion; there is no obligate external rotation, and he can bear weight with a limp. He is Tanner stage 2. Radiographs from an urgent care are described as "normal hip, no fracture." His parents ask whether he can play in a showcase in 10 days.
1. Which findings would make you stop and consider a more urgent diagnosis than an apophyseal injury, and how would you act on them?
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The case as presented fits an acute anterior inferior iliac spine avulsion on a background of 3 weeks of apophyseal overload, but the job of the first visit is to exclude the diagnoses that change disposition.
Red flags for slipped capital femoral epiphysis: inability to bear weight, pain out of proportion, night or rest pain, systemic features, and - most specifically - obligate external rotation of the hip in flexion. He has none of these, which is reassuring, but he is at the younger end of the SCFE window and a "normal hip" read from an urgent care is not the same as a frog-leg lateral read by someone looking for it.
Red flags for infection or malignancy: fever, night pain, weight loss, rest pain, or a markedly restricted and irritable hip. Any of these converts the visit into same-day labs and imaging and a referral, not a training plan.
Red flags for a significant avulsion: inability to bear weight, a palpable gap, or displacement. Those change the conversation from conservative loading to orthopedic involvement.
Action: if any red flag is present, no sport, urgent imaging and referral. If none are present, proceed with the apophyseal plan but still obtain adequate imaging.
2. Which imaging do you order, and why are the urgent care films insufficient?
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Order: a properly positioned anteroposterior pelvis and a frog-leg lateral view, read specifically for physeal widening or step-off at the proximal femur, and for the AIIS apophysis. Ultrasound of the AIIS with a focused probe is fast, cheap, and sensitive for an apophyseal avulsion with a hematoma or gap, and can be done the same day. MRI, ideally without contrast, is reserved for cases where the radiograph and ultrasound are equivocal, where a cartilaginous or minimally ossified avulsion is suspected, or where red flags demand soft-tissue and marrow evaluation.
The urgent care films are insufficient for two reasons. First, a single AP view does not show the frog-leg lateral profile where SCFE is detected, so "normal hip" was never actually established. Second, in a Tanner 2 patient much of the apophysis is cartilaginous and therefore radiolucent; a nondisplaced avulsion or apophysitis can look unremarkable on plain film. Age-appropriate interpretation of the apophyseal region, not the presence of a report, is what matters. He needs both hips visualized for comparison on the same image set.
3. Give your management plan and your answer to the family about the 10-day showcase.
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Management: this is a physeal/apophyseal injury in a growing athlete, so the plan is protection, then graded load, with the timeline set by symptoms and function rather than by the calendar.
- Relative rest from kicking and sprinting; crutches with partial weight bearing for comfort for the first 1–3 weeks if the limp persists.
- Avoid stretching the rectus femoris into hip extension and knee flexion early - the avulsed apophysis is under tensile load, and aggressive stretching is the most common setback.
- Isometric hip flexion progressing to short-range concentric work, then closed-chain loading, then running, then kicking, then sprinting and shooting. Typical return for a low-grade avulsion is 6–12 weeks; surgical referral is reserved for displacement of roughly 2 cm or more, or a large retracted fragment.
The family needs a direct answer: 10 days is not realistic for a full return, and returning him to shooting at that point risks converting a healing avulsion into a displaced one. Offer a modified role if the coach can use him - sideline, no kicking - and explain that the 3-week prodrome of groin aching suggests this was brewing before the pop, which lengthens rather than shortens the timeline. Document the conversation.