Overview
Definition:
Slipped Capital Femoral Epiphysis (SCFE) is an endocrine-related condition occurring in adolescence where the femoral head (epiphysis) displaces from its normal position at the neck of the femur through the physis (growth plate)
This slippage typically occurs in a posterior and inferior direction.
Epidemiology:
SCFE is the most common hip disorder in adolescents, with an incidence of approximately 10-15 per 100,000 adolescents
It predominantly affects males, typically between the ages of 10-16 years, and is often bilateral (occurring in 20-50% of cases)
Risk factors include obesity, endocrine disorders (hypothyroidism, hypogonadism, growth hormone deficiency), renal osteodystrophy, and rapid growth spurts.
Clinical Significance:
SCFE is a critical condition due to its potential for long-term morbidity, including avascular necrosis of the femoral head, chondrolysis (rapid joint degeneration), and secondary osteoarthritis
Prompt diagnosis and appropriate management are crucial to minimize these complications and preserve hip function.
Clinical Presentation
Symptoms:
Groin pain, often unilateral
Limp
Pain may radiate to the thigh or knee
Affected leg may appear shorter
Pain can be insidious or acute after trauma
Limited range of motion in the hip, particularly internal rotation.
Signs:
Antalgic gait
Affected leg may be externally rotated
Positive Trendelenburg sign
Limited internal rotation of the hip on passive examination
Pain on palpation of the hip joint
Affected leg may be shorter than the contralateral side.
Diagnostic Criteria:
Diagnosis is primarily clinical and radiological
Clinical suspicion based on age, obesity, and pain presentation
Radiographic confirmation typically requires anteroposterior (AP) and lateral radiographs of both hips
In subtle cases, a frog-leg lateral view or MRI may be necessary.
Diagnostic Approach
History Taking:
Age of patient
Onset and duration of symptoms
Nature of pain (constant vs
intermittent, location, radiation)
History of trauma
Weight history (obesity)
Family history of hip problems
Symptoms suggestive of endocrine disorders (e.g., delayed puberty, polyuria, polydipsia).
Physical Examination:
Gait assessment for limping
Palpation of the hip and groin for tenderness
Assess hip range of motion, focusing on abduction, adduction, flexion, extension, internal rotation, and external rotation
Measure leg lengths
Assess for external rotation of the affected limb in flexion
Perform Trendelenburg test.
Investigations:
Radiographs: AP pelvis and both hips, lateral view of affected hip (or frog-leg lateral)
Findings include widening of the physis, a decrease in epiphyseal height, and the characteristic posterior-inferior displacement of the epiphysis
Measurement of the epiphyseal-diaphyseal angle (Southwick classification)
MRI can be useful for detecting subtle slips or complications like avascular necrosis
Blood tests may be indicated to rule out endocrine or metabolic causes (e.g., thyroid function tests, IGF-1, testosterone levels).
Differential Diagnosis:
Transient synovitis
Septic arthritis
Osteomyelitis
Perthes disease
Inflammatory arthropathies (juvenile idiopathic arthritis)
Referred pain from the knee or spine
Other causes of limp and hip pain.
Management
Initial Management:
Immediate non-weight-bearing status on the affected limb is crucial to prevent further slippage
Admission to hospital for pain control and further evaluation
Analgesia as needed.
Surgical Management:
The primary goal of surgical management is in-situ fixation, preventing further slippage
Indications for surgery include any diagnosed SCFE
Procedure: Screw fixation (e.g., cannulated screws) across the physis into the epiphysis, maintaining anatomical reduction as much as possible
For unstable slips or those with significant displacement, osteotomies (e.g., Dunn osteotomy) may be considered to realign the epiphysis, but this carries a higher risk of complications
Bilateral prophylactic fixation may be considered in certain high-risk patients or if the contralateral epiphysis is open.
Weight Bearing Limits:
Post-operative weight-bearing is strictly dictated by the surgeon's assessment and the stability of the fixation
Generally, patients are kept non-weight-bearing or toe-touch weight-bearing for 6-12 weeks post-operatively
Gradual progression to partial weight-bearing and then full weight-bearing is guided by radiographic evidence of bony healing and clinical stability
Complete freedom from weight-bearing restrictions typically occurs after physeal closure and evidence of stable union, usually several months post-surgery.
Supportive Care:
Pain management with appropriate analgesics
Physical therapy for range of motion and strengthening exercises once weight-bearing is permitted
Close monitoring for signs of complications such as infection, avascular necrosis, or chondrolysis.
Complications
Early Complications:
Avascular necrosis of the femoral head
Chondrolysis
Screw migration or loosening
Infection
Nerve injury (rare).
Late Complications:
Premature osteoarthritis of the hip
Femoral head deformity leading to femoroacetabular impingement (FAI)
Chronic pain
Leg length discrepancy
Stiffness and loss of range of motion.
Prevention Strategies:
Prompt surgical stabilization to prevent further slippage
Careful surgical technique
Maintaining reduction during fixation
Careful management of weight-bearing restrictions
Early recognition and management of associated endocrine or metabolic conditions.
Prognosis
Factors Affecting Prognosis:
Severity and duration of symptoms prior to diagnosis
Degree of epiphyseal displacement
Presence of avascular necrosis or chondrolysis
Quality of surgical fixation and reduction
Management of underlying endocrine disorders.
Outcomes:
With prompt diagnosis and appropriate in-situ fixation, the prognosis is generally good, preserving hip function
However, patients with severe slips, delayed diagnosis, or complications like avascular necrosis or chondrolysis have a poorer prognosis and are at higher risk for developing early osteoarthritis
Long-term follow-up is essential.
Follow Up:
Regular clinical and radiographic follow-up is mandatory
Initial follow-up is typically at 2-3 weeks post-operatively, then at 6-12 weeks, 3 months, 6 months, 1 year, and annually thereafter until skeletal maturity
Monitoring for signs of complications, physeal closure, and progression to osteoarthritis.
Key Points
Exam Focus:
SCFE is a displacement of the epiphysis through the physis
Obesity is a major risk factor
Pain is often in the knee, not the hip
Radiographic hallmark is posterior-inferior slippage
In-situ fixation is the primary surgical treatment
Strict non-weight-bearing post-op is critical.
Clinical Pearls:
Always suspect SCFE in an obese adolescent with knee or hip pain and a limp, especially with limited internal rotation
Bilateral symptoms are common
consider prophylactic pinning in high-risk contralateral hips
Assess leg length discrepancy and external rotation in flexion.
Common Mistakes:
Dismissing knee pain as solely musculoskeletal without evaluating the hip
Delaying surgical intervention due to perceived low risk of slippage
Inadequate post-operative weight-bearing restrictions
Failing to consider bilateral involvement.