An 11-year-old obese African-American boy presents with a sudden onset of limp. What should be the likely diagnosis and workup?

The presentation of an 11-year-old obese African-American boy with a sudden onset of limp is highly suggestive of slipped capital femoral epiphysis (SCFE). This condition is characterized by displacement of the femoral head due to slippage at the growth plate (physis), which is often precipitated by factors such as obesity, growth spurts, and certain hormonal changes.

In terms of diagnosis, the appropriate imaging studies to confirm SCFE would include anteroposterior (AP) and frog-leg lateral x-rays of the hip. These x-rays will typically reveal the characteristic displacement of the femoral head and help in assessing the degree of slippage, which can be important for treatment planning.

While other conditions such as osteomyelitis, transient synovitis, and fractures may present with similar symptoms, the specific combination of age, demographic factors, and the sudden onset of limping aligns most closely with SCFE. The workup for these other conditions would involve different imaging modalities or techniques tailored to their specific pathologies, making the approach to SCFE unique in this case.