S49.149 Salter-Harris Type IV physeal fracture of lower end of humerus, unspecified arm

Name of the Condition

• Salter-Harris Type IV physeal fracture of lower end of humerus, unspecified arm (ICD-10 Code: S49.149)

Summary

This code describes a Salter-Harris Type IV fracture involving the growth plate (physeal) at the lower end of the humerus, with the arm side unspecified. This type of fracture extends through the metaphysis, physis, and epiphysis, potentially disrupting both bone growth and joint stability. It is most common in children and adolescents due to the relative weakness of the growth plate during development.

Causes

Trauma is the primary cause, typically resulting from a fall onto an outstretched hand or a direct blow to the elbow. Sports-related injuries, such as those from contact sports or activities involving forceful arm movement, are frequent mechanisms. The force applied to the elbow can cause a complex fracture involving multiple bone structures.

Risk Factors

• Age (most common in children and adolescents with open growth plates)
• Participation in high-impact or contact sports
• Prior growth plate injuries or developmental abnormalities
• Activities involving repetitive stress on the elbow

Symptoms

• Pain and swelling localized to the elbow or lower arm
• Tenderness over the distal humeral growth plate
• Limited range of motion in the affected arm
• Possible visible deformity in severe cases
• Difficulty moving or bearing weight on the arm

Diagnosis

Diagnosis relies on a physical examination to assess pain, swelling, and range of motion, followed by imaging studies such as X-rays or MRI to visualize the fracture pattern. The vertical fracture line extending through the metaphysis, physis, and epiphysis is characteristic of Salter-Harris Type IV injuries. Clinical correlation with the mechanism of injury is essential for accurate diagnosis.

Treatment Options

Treatment depends on fracture displacement and stability. Nondisplaced fractures may be managed with immobilization (e.g., casting) and close monitoring. Displaced fractures typically require surgical intervention to realign the bone and stabilize the growth plate, often using pins or screws. Post-treatment, physical therapy may be recommended to restore function and strength.

Prognosis and Follow-Up

Prognosis varies based on fracture severity, treatment timing, and adherence to follow-up care. Early intervention improves outcomes, but there is a risk of growth plate disturbance or joint instability if the fracture is not properly aligned. Regular follow-up with imaging and clinical assessments is necessary to monitor healing and detect complications.

Complications

Potential complications include growth plate arrest (leading to limb length discrepancy or angular deformity), joint stiffness, chronic pain, or arthritis. Incomplete healing or malunion may require additional interventions. Prompt recognition and management reduce these risks.

Lifestyle & Prevention

Preventive measures include using protective gear during sports, avoiding high-risk activities, and ensuring proper technique to reduce fall or injury risk. For children, regular check-ups can help identify and address developmental concerns early. Strengthening exercises for the arm and elbow may improve resilience.

When to Seek Professional Help

Seek immediate medical attention for severe pain, visible deformity, inability to move the arm, or after a significant injury. Persistent swelling, fever, or signs of infection (e.g., redness, warmth) also warrant prompt evaluation.

Tips for Medical Coders

Use this code for Salter-Harris Type IV physeal fractures of the lower humerus when the arm side is not specified. Ensure documentation supports the fracture type and location. Differentiate from other Salter-Harris types or fractures involving other humeral regions. Verify that the injury is acute and not a sequela or chronic condition.