M93.01 Acute slipped upper femoral epiphysis (nontraumatic)

Name of the Condition

• Acute slipped upper femoral epiphysis (nontraumatic)

Summary

Acute slipped upper femoral epiphysis (SUFE) is a condition where the femoral head (ball of the hip joint) shifts from its normal position on the femoral neck due to a fracture through the growth plate. This nontraumatic form occurs without a specific injury and typically presents acutely, meaning symptoms develop suddenly. The condition primarily affects adolescents during growth spurts and can lead to hip pain, stiffness, or gait changes. Prompt evaluation is important to prevent complications.

Causes

The exact cause of acute nontraumatic SUFE is not fully understood, but it is thought to result from mechanical stress on the growth plate combined with hormonal influences during puberty. Reduced blood flow to the growth plate may weaken the bone, allowing the femoral head to slip. Obesity is also considered a contributing factor due to increased mechanical load on the hip. The acute presentation suggests a sudden displacement, possibly due to cumulative stress or a minor, unrecognized event.

Risk Factors

• Age: Most common in adolescents aged 10-16 years, particularly during rapid growth spurts.
• Gender: Males are more frequently affected than females.
• Obesity: Higher body weight increases stress on the hip joint.
• Endocrine disorders: Conditions like hypothyroidism or growth hormone abnormalities may elevate risk.
• Prior SUFE: A history of SUFE in the contralateral hip increases the risk of acute displacement.

Symptoms

• Hip, thigh, or knee pain (pain may be referred to the knee).
• Limp or altered gait (e.g., walking with a limp or toe-out stance).
• Reduced range of motion in the hip, especially internal rotation.
• External rotation of the leg when flexed.
• Pain worsened by activity or weight-bearing.
• Mild swelling or tenderness in the hip or groin area.

Diagnosis

Diagnosis involves a physical exam to assess hip range of motion, gait, and tenderness. Imaging studies, such as X-rays or MRI, are typically used to confirm the displacement of the femoral head. The acute nature of the condition may require urgent evaluation to rule out complications like avascular necrosis. Clinical history, including growth patterns and risk factors, also aids in diagnosis.

Treatment Options

Treatment focuses on stabilizing the femoral head to prevent further displacement. Surgical intervention, such as in-situ pinning, is often recommended to fix the epiphysis in place. Non-surgical options, like activity modification and pain management, may be considered in mild cases, but surgery is generally preferred for acute presentations. Postoperative care includes restricted weight-bearing and physical therapy to restore function.

Prognosis and Follow-Up

With prompt treatment, most patients recover well, though long-term monitoring is necessary to assess for complications like avascular necrosis or arthritis. Follow-up visits typically involve imaging to check for stability and functional assessments. Adolescents may require ongoing orthopedic care until growth is complete. Early intervention improves outcomes and reduces the risk of chronic issues.

Complications

• Avascular necrosis (loss of blood supply to the femoral head).
• Premature osteoarthritis due to joint damage.
• Chronic pain or limited mobility.
• Gait abnormalities or limb length discrepancy.
• Recurrence of displacement if not properly stabilized.

Lifestyle & Prevention

Maintaining a healthy weight reduces stress on the hip joint. Regular physical activity supports bone health, but high-impact sports should be approached cautiously. Adolescents with risk factors (e.g., obesity, endocrine disorders) should be monitored for early symptoms. Prompt evaluation of hip or knee pain in this age group is key to prevention.

When to Seek Professional Help

Seek medical attention if an adolescent experiences sudden hip, thigh, or knee pain, especially with a limp or reduced mobility. Immediate care is needed if weight-bearing becomes difficult or pain worsens rapidly. Early diagnosis and treatment minimize complications.

Tips for Medical Coders

Document the acute nature of the condition, as this distinguishes it from chronic or unspecified forms. Include details about the affected hip (if specified) and any contributing factors like obesity or endocrine disorders. Ensure clinical documentation supports the nontraumatic etiology, as this is critical for accurate coding.