Slipped Capital Femoral Epiphysis: Symptoms, Types, Causes and Treatment

Slipped Capital Femoral Epiphysis (SCFE) is a serious hip disorder that most commonly affects children and adolescents during their growth spurts. Timely recognition and management are crucial to prevent lifelong complications, such as hip deformity, chronic pain, and early arthritis. This comprehensive article will guide you through the key symptoms, classifications, underlying causes, and modern treatment options for SCFE, grounded in the latest evidence and clinical research.

Symptoms of Slipped Capital Femoral Epiphysis

Recognizing SCFE early can make all the difference in outcomes for young patients. The symptoms can be subtle at first but often progress, sometimes leading to misdiagnosis or delayed treatment. Understanding the typical signs and how they present is essential for parents, caregivers, and healthcare providers.

Symptom	Description	Frequency/Pattern	Source(s)
Hip Pain	Ache or sharp pain in the hip/groin	Most common, can be chronic or acute	3 4 5 10
Thigh/Knee Pain	Pain referred to thigh or knee	Occurs in up to 12% of cases	4 5 10
Limping	Abnormal gait or limp	Common in ambulatory patients	4 5 10
Inability to Walk	Severe pain, nonambulatory	Seen in unstable/acute cases	1 4 7
Stiffness	Reduced hip movement	May be present in chronic cases	3 5
Bilateral Symptoms	Both hips affected	7% at presentation; up to 21% later	5

Table 1: Key Symptoms

Understanding SCFE Symptoms

Hip, Thigh, and Knee Pain

• Hip/groin pain is the hallmark of SCFE, but the pain can sometimes radiate to the thigh or even the knee. Such referred pain may mislead clinicians, delaying diagnosis, especially when knee pain is the presenting complaint 4 5 10.
• Knee pain occurs in about 12% of cases and is associated with the longest diagnostic delays (median of 161 days compared to 20 days for hip pain) 10. This highlights the importance of considering SCFE in any adolescent with unexplained knee pain.

Limping and Abnormal Gait

• Many children with SCFE develop a noticeable limp, often described as an "antalgic gait." The limp can be subtle or pronounced, depending on the severity and chronicity of the slip 4 5.

Severity-Dependent Presentation

• Stable SCFE: Patients can often still walk, albeit with a limp, and may report chronic, dull pain.
• Unstable SCFE: Children present with sudden, severe pain and are unable to bear weight, even with crutches. This is a surgical emergency 1 4 7.

Bilateral and Progressive Symptoms

• SCFE may affect both hips, either simultaneously (7% at initial presentation) or sequentially (up to 21% later) 5. Regular monitoring of both hips is therefore crucial.

Other Signs

• Stiffness or restricted motion in the hip, particularly with internal rotation, can be an early clue.
• Over time, unnoticed or untreated slips can lead to leg length discrepancy or persistent mobility issues 3 5.

Types of Slipped Capital Femoral Epiphysis

SCFE is not a one-size-fits-all condition. Its classification helps guide the urgency and type of treatment. The most clinically relevant system classifies SCFE based on "stability," which has direct implications for prognosis and management.

Type	Defining Feature	Clinical Significance	Source(s)
Stable	Able to walk (with/without crutches)	Lower risk for complications	1 4 6 7 12
Unstable	Cannot walk, even with crutches	Higher risk for AVN, urgent care needed	1 4 7 12
Acute	Symptoms <3 weeks	Often overlaps with unstable	1 3 4
Chronic	Symptoms >3 weeks	Usually stable, gradual onset	3 5 8
Acute-on-Chronic	Sudden worsening on chronic symptoms	Variable stability, higher risk	1 3

Table 2: SCFE Types

Breaking Down SCFE Types

Stability-Based Classification

• Stable SCFE: The child can still walk, even if aided by crutches. This type has a much better prognosis, with a markedly lower risk of complications such as avascular necrosis (AVN). Most stable slips are managed with less aggressive surgical interventions 1 4 6 12.
• Unstable SCFE: The child cannot walk at all, even with crutches. This presentation is associated with severe pain and a high risk (up to 47%) of AVN if not treated emergently 1 4 7 12. Unstable slips require urgent surgical intervention.

Time-Based Classification

• Acute: Symptoms present for less than three weeks. These cases are more likely to be unstable and painful 1 3 4.
• Chronic: Symptoms persist for more than three weeks, often with a subtle onset and gradual worsening. Most chronic slips are stable 3 5 8.
• Acute-on-Chronic: A child with chronic mild symptoms suddenly develops severe pain, indicating a new or worsening slip 1 3.

Importance of Classification

• Proper classification is critical as it influences treatment choice and prognosis. Stability is the single most important determinant of outcome, particularly regarding the risk for AVN 1 4 6 12.

Causes of Slipped Capital Femoral Epiphysis

The precise cause of SCFE remains complex and multifactorial. However, research has identified several major risk factors and underlying mechanisms that increase vulnerability.

Cause/Risk Factor	Description	Impact/Prevalence	Source(s)
Obesity	Excess weight increases shear stress	Present in 56–76% of cases	3 5 9 10
Growth Spurts	Rapid growth weakens the growth plate	Most cases in early teens	3 4 5
Hormonal Changes	Endocrine disorders or puberty hormones	Associated with increased risk	3 4 8
Biomechanical Factors	Shearing forces at growth plate	Can cause physis to slip	3 4 8
Socioeconomic Status	Higher rates in deprived populations	Strong association	10
Ethnicity	Higher incidence in African-American males	Males 2x more affected	3 5 10
Genetic Predisposition	Family history, genetic factors	Less well-defined	4 8

Table 3: Causes and Risk Factors

Exploring the Causes of SCFE

Obesity: The Most Significant Modifiable Risk

• Overweight and obesity are the most prominent risk factors, present in over half of girls and three-quarters of boys with SCFE 3 5 9 10.
• Rising rates of childhood obesity have paralleled increases in SCFE incidence worldwide 9.
• Excess body weight increases the shear forces across the vulnerable growth plate (physis), making it more likely to slip.

Growth-Related Factors

• SCFE occurs almost exclusively during rapid growth phases, typically between ages 9 and 15 3 4 5.
• The physis temporarily weakens during growth spurts, making it more susceptible to displacement.

Hormonal and Biochemical Influences

• Endocrine disorders (such as hypothyroidism) and hormonal changes during puberty can alter physis strength and architecture 3 4 8.
• Some cases are associated with underlying metabolic or renal disorders.

Biomechanical Stresses

• The combination of increased weight and biomechanical forces (e.g., running, twisting) acts on an already weakened physis, leading to a slip 3 4 8.

Socioeconomic and Demographic Factors

• SCFE is more common among children from socioeconomically deprived backgrounds 10.
• Males are affected about twice as often as females, and African-American children have a higher incidence 3 5 10.

Genetic and Other Considerations

• While most cases are sporadic, there may be a genetic predisposition, especially in cases with family history or bilateral involvement 4 8.

Treatment of Slipped Capital Femoral Epiphysis

The mainstay of SCFE treatment is surgical, with the approach tailored to the stability and severity of the slip. Timely intervention is vital to prevent further displacement and complications such as avascular necrosis (AVN) and early arthritis.

Treatment	Indication	Outcome/Complications	Source(s)
In situ pinning	Stable SCFE, mild/moderate slips	Low AVN risk, preserves anatomy	4 6 7 8 11 12
Modified Dunn osteotomy	Severe stable slips, some unstable	Restores anatomy; higher AVN risk	7 8 13 14
Urgent reduction + Fixation	Unstable SCFE	Necessary to prevent AVN	4 7 11 12
Spica cast	Rare, some chronic/acute-on-chronic	Low AVN risk; chondrolysis possible	15
Prophylactic fixation	Contralateral hip at risk	Prevents later slip	5
Weight loss, medical management	All cases (supportive)	Reduces recurrence, improves health	11

Table 4: SCFE Treatment Options

Surgical Management

In Situ Pinning

• First-line for stable SCFE: A single screw is placed across the growth plate to stabilize the slipped epiphysis without attempting to realign it 4 6 12.
• Advantages: Minimizes risk of avascular necrosis (AVN; ~1.4% incidence), preserves blood supply and hip function 6.
• Outcomes: Most patients have good or excellent function, though some residual deformity (which can lead to impingement) may persist 6 8 11.

Modified Dunn Procedure (Surgical Hip Dislocation)

• Indication: Severe stable slips, or selected unstable cases 7 8 13 14.
• How it works: The hip is surgically dislocated and the head realigned, correcting deformity.
• Benefits: Restores near-normal hip anatomy, reducing risk of future arthritis and femoroacetabular impingement (FAI) 13 14.
• Risks: Higher rate of AVN (3–10%), especially in unstable slips or if blood supply is compromised during surgery 6 7 13 14.

Urgent Reduction and Fixation

• Indication: Unstable SCFE (unable to walk, severe pain).
• Approach: Gentle reduction (if possible), decompression of intracapsular pressure, and internal fixation. This reduces the risk of AVN, which can be as high as 47% in unstable slips 1 4 7 11 12.
• Techniques: Both closed and open approaches may be used; intraoperative assessment of blood supply (with imaging or Doppler) is increasingly common 7.

Other Surgical Options

• Osteotomies: Realignment procedures may be considered in some chronic or severe stable cases, but carry increased risks and are technically demanding 7 8.
• Spica Cast: Rarely used today, but may be considered in select chronic or acute-on-chronic cases; risk of chondrolysis must be weighed 15.

Prophylactic Fixation

• Purpose: To prevent a slip in the contralateral (other, unaffected) hip, especially in high-risk patients (obese, young, or those with endocrine disorders) 5.

Non-Surgical Management and Support

• Weight Loss & Medical Optimization: Addressing obesity, hypertension, and other comorbidities is important for long-term health and surgical outcomes 11.
• Physical Therapy: Essential in rehabilitation after surgery to restore mobility and strength.

Complications to Watch For

• Avascular Necrosis (AVN): Loss of blood supply to the femoral head, leading to collapse and arthritis; risk is highest with unstable slips and some surgical realignment procedures 1 6 11 13.
• Chondrolysis: Rapid loss of cartilage, leading to stiffness and pain; much less common with modern surgical techniques 11 15.
• Femoroacetabular Impingement (FAI): Residual deformity after SCFE can cause abnormal contact in the hip joint, leading to pain and early arthritis if not corrected 8 13 14.

Conclusion

Slipped Capital Femoral Epiphysis is a challenging yet treatable pediatric hip disorder. Early recognition, accurate classification, and timely intervention are key to ensuring the best possible outcomes for affected children. The evidence strongly supports a stability-based approach to classification and management, with in situ pinning as the mainstay for stable cases and urgent surgical intervention for unstable ones. Addressing underlying risk factors, especially obesity, is also crucial for prevention and long-term health.

Key Points:

• SCFE typically presents with hip, thigh, or knee pain, and may cause limping or inability to walk.
• Classification based on stability (stable vs. unstable) is vital for guiding treatment and predicting outcomes.
• Obesity, rapid growth, and hormonal changes are major contributing factors.
• The standard treatment is in situ pinning for stable slips and urgent reduction plus fixation for unstable slips.
• Severe deformities may require corrective osteotomy, but with higher risks.
• Early diagnosis and intervention are essential to prevent complications like avascular necrosis and early arthritis.

Understanding SCFE empowers families and clinicians to act quickly, ensuring children can return to healthy, active lives.