CASE 75
By: Dr. Amna Kashgari MD,SSC-Rad
HISTORY: A 12-year-old boy presented with right hip pain.
What is your finding?
What is the differential diagnosis?
What is your diagnosis?
FINDINGS:
Frontal radiograph of the pelvis demonstrates a widening of the growth plate of the right femur with irregularity and blurring of the physeal edges.
Frog leg view of the right hip shows a displacement of the right femoral epiphysis medially and the metaphysis displaced laterally.
DIFFERENTIAL DIANGOSIS:
Legg-Calve-Perthes disease.
Septic arthritis.
Slipped capital femoral epiphysis (SCFE).
Transient synovitis.
Developmental dysplasia.
DIAGNOSIS:
Slipped capital femoral epiphysis (SCFE).
Complications:
Avascular necrosis.
Early osteoarthritis.
Chondrolysis.
Leg length discrepancy.
PEARLS AND DISCUSSION:
Slipped capital femoral epiphysis is the most common hip disorder in adolescent with a prevalence of 10.8 per 100,000. It is more common in boy than girl between 10-15 years.
Risk factors:
Black.
Growth surges.
Overweight.
Endocrine (hypothyroidism, hypopituitarism, hyperparathyroidism disorder).
Clinical presentation is usually with limping and dull hip pain with a lack of history of trauma. On physical examination, the patient is usually unable to bare weight with limited internal hip rotation.
Classification of the disease is usually done clinically. If the patient is ambulatory, the SCFE is stable. But, if the patient is not ambulatory, the SCFE is considered unstable.
Diagnosis is made using AP pelvis and lateral frog-leg radiographs. CT-scan is a sensitive method for measuring the degree of tilt and detecting disease, but it is rarely needed. Low dose technique should be performed.
MRI scan shows bone marrow edema in early stages. It is used usually to assess the contralateral hip joint.
Early in SCFE, on AP film, the physis may widen and appear irregular. The epiphysis may appear smaller as it tilted dorsally. A line drawn up on the lateral edge of the femoral neck “Klein line” fails to intersect the epiphysis during the acute phase.
The lateral radiograph demonstrates slippage earliest because the slippage begins with posterior displacement and progresses with a medial rotation of the epiphysis with lateral displacement of the metaphysis.
The severity of the disease is measured radiologically based on frog leg view “Wilson method”:
Mild: displacement less than one third of the width of the metaphysis.
Moderate: displacement between one third and half of the width of the metaphysis.
Sever: displacement greater than one half of the width of the metaphysis.
Treatment to avoid complication:
Non-weight bearing crutches.
Screw fixation.
FURTHER READING:
Davied Peck. Slipped Capital Femoral Epiphysis: Diagnosis and Management. American Family Physician (2010) Vol 82-3.
Lane F Donnelly. Fundamental of pediatric radiology. ISBN-13: 978-0721690612
Johan G Blickman, Bruce R Parker, Patrick D Barnes. Pediatric Radiology: The Requisites.
ISBN-10: 0323031250
