S79.12 Salter-Harris Type II physeal fracture of lower end of femur

Name of the Condition

Salter-Harris Type II physeal fracture of lower end of femur

Summary

A Salter-Harris Type II physeal fracture of the lower end of the femur is an injury involving the growth plate (physis) at the distal femur, typically occurring in children or adolescents. This fracture disrupts the physis, which is the area of developing bone responsible for longitudinal growth. The injury specifically involves a separation of the growth plate with a fracture through the metaphysis, as defined by the Salter-Harris classification system.

Causes

Salter-Harris Type II physeal fractures of the lower femur are usually caused by acute trauma, such as falls, sports-related injuries, or direct blows to the knee or thigh. The force transmitted across the growth plate can cause it to separate from the adjacent bone, often with associated metaphyseal damage. In some cases, repetitive stress or overuse may contribute to the injury, particularly in active children or adolescents.

Risk Factors

• Age: Most common in children and adolescents, as growth plates are weaker than surrounding bone.
• Activity level: Participation in high-impact sports or activities with a risk of falls (e.g., gymnastics, soccer, skateboarding).
• Growth spurts: Periods of rapid growth may temporarily weaken the physis, increasing susceptibility to injury.
• Anatomical factors: Variations in bone structure or prior injuries may predispose individuals to physeal fractures.

Symptoms

• Pain and swelling at the knee or thigh
• Limited range of motion in the affected leg
• Visible deformity or misalignment in severe cases
• Difficulty bearing weight or walking
• Tenderness to touch at the fracture site

Diagnosis

Diagnosis typically involves a physical examination to assess pain, swelling, and range of motion, followed by imaging studies. X-rays are the primary tool to visualize the fracture and confirm the Salter-Harris Type II pattern, which includes a metaphyseal fragment. In some cases, additional imaging like MRI may be used to evaluate soft tissue damage or assess growth plate integrity.

Treatment Options

Treatment depends on the severity and displacement of the fracture. Nondisplaced fractures may be managed with immobilization (e.g., casting or bracing) and activity restriction. Displaced fractures often require closed reduction (realignment) or surgical intervention to restore proper alignment and stabilize the growth plate. Follow-up imaging ensures proper healing and growth plate function.

Prognosis and Follow-Up

Prognosis is generally favorable with appropriate treatment, though outcomes depend on the extent of displacement and potential growth plate damage. Regular follow-up appointments monitor healing, alignment, and growth. Long-term monitoring may be necessary to assess for growth disturbances or limb length discrepancies.

Complications

• Growth plate damage leading to limb length discrepancy or angular deformity
• Premature closure of the growth plate
• Infection (if surgical intervention is required)
• Stiffness or reduced range of motion in the knee
• Chronic pain or arthritis in adulthood

Lifestyle & Prevention

• Use protective gear during high-impact sports (e.g., helmets, pads)
• Ensure proper warm-up and technique to reduce injury risk
• Maintain bone health through adequate nutrition (e.g., calcium, vitamin D)
• Avoid overuse or repetitive stress on the knee in growing children
• Supervise activities with fall risks for younger children

When to Seek Professional Help

Seek immediate medical attention if there is severe pain, inability to bear weight, visible deformity, or signs of nerve or vascular compromise (e.g., numbness, coldness). Prompt evaluation is critical to prevent complications and ensure proper healing.

Tips for Medical Coders

Code S79.12 is specific to Salter-Harris Type II physeal fractures of the lower femur. Documentation should clearly specify the fracture type (Type II) and location (lower end of femur) to support accurate coding. Include details on displacement, treatment, and any associated injuries to ensure comprehensive coding. Avoid using this code for unspecified or other Salter-Harris types; use the appropriate code for the specific fracture pattern documented.