S49.129A Salter-Harris Type II physeal fracture of lower end of humerus, unspecified arm, initial encounter for closed fracture

Name of the Condition

• Salter-Harris Type II physeal fracture of lower end of humerus, unspecified arm, initial encounter for closed fracture (ICD-10 Code: S49.129A)

Summary

This code describes a Salter-Harris Type II fracture involving the growth plate (physeal) at the lower end of the humerus, with a fragment of the metaphysis (adjacent bone) included. It is an initial encounter for a closed fracture, meaning the skin is intact and no surgical intervention has occurred. This injury is common in children and adolescents due to the relative weakness of the growth plate compared to surrounding bone, typically affecting the distal humeral physis where the upper arm meets the elbow joint.

Causes

Trauma is the primary cause, often 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 disrupt the growth plate and pull a small piece of the metaphysis with it.

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 is typically made through clinical evaluation and imaging. A physical exam assesses pain, swelling, and range of motion. X-rays are the primary imaging tool, showing the fracture pattern through the growth plate and metaphysis. In some cases, additional imaging (e.g., MRI) may be used to evaluate soft tissue involvement or confirm the fracture type.

Treatment Options

Treatment depends on fracture severity and displacement. Non-displaced fractures may be managed with immobilization (e.g., cast or splint) and activity modification. Displaced fractures often require closed reduction (realignment) under anesthesia, followed by casting. Severe cases may need surgical intervention to stabilize the fracture.

Prognosis and Follow-Up

Prognosis is generally good with appropriate treatment, especially for non-displaced fractures. Follow-up care includes monitoring for healing and assessing for complications like growth disturbances. Physical therapy may be recommended to restore range of motion and strength. Long-term follow-up ensures normal growth and function.

Complications

• Growth plate disturbance leading to limb length discrepancy or angular deformity
• Stiffness or limited range of motion
• Nonunion or malunion of the fracture
• Nerve or vascular injury (rare)

Lifestyle & Prevention

• Use protective gear during sports or high-risk activities
• Ensure proper technique and training to reduce injury risk
• Maintain bone health with adequate nutrition (e.g., calcium, vitamin D)
• Avoid overuse or repetitive stress on the elbow in children

When to Seek Professional Help

Seek immediate medical attention if there is severe pain, swelling, deformity, or inability to move the arm. Prompt evaluation is critical to prevent complications and ensure proper treatment.

Tips for Medical Coders

This code is specific to an initial encounter for a closed fracture of the unspecified arm. Document the fracture type (Salter-Harris II), location (lower humerus), arm (unspecified), encounter type (initial), and fracture status (closed) to support accurate coding. Ensure clinical documentation aligns with the code’s specificity to avoid miscoding.