S79.149K Salter-Harris Type IV physeal fracture of lower end of unspecified femur, subsequent encounter for fracture with nonunion

Name of the Condition

Salter-Harris Type IV physeal fracture of lower end of unspecified femur, subsequent encounter for fracture with nonunion

Summary

A Salter-Harris Type IV physeal fracture of the lower end of the unspecified femur is an injury involving the growth plate (physis) at the distal femur, typically occurring in children or adolescents. This fracture disrupts the physis and involves a fracture through the metaphysis, physis, and epiphysis, as defined by the Salter-Harris classification system. The injury may result in displacement of bone fragments and potential damage to the growth plate, which is critical for longitudinal bone growth. This code specifies a subsequent encounter for a fracture with nonunion, indicating the fracture has not healed properly after treatment.

Causes

Salter-Harris Type IV 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 and fracture through multiple bone regions. In some cases, repetitive stress or overuse may contribute to the injury, particularly in active children and 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.
• Previous fractures: A history of prior growth plate injuries may predispose to nonunion.

Symptoms

• Pain and swelling at the fracture site, often localized to the knee or thigh.
• Limited range of motion in the affected leg.
• Visible deformity or misalignment of the limb.
• Difficulty bearing weight or walking.
• Persistent pain despite initial treatment, indicating potential nonunion.

Diagnosis

Diagnosis involves a physical examination to assess pain, swelling, and deformity. Imaging studies, such as X-rays, are typically used to visualize the fracture and confirm nonunion. Advanced imaging, like CT or MRI, may be employed to evaluate the extent of damage to the growth plate and surrounding structures. Clinical history, including the mechanism of injury and prior treatment, is also considered.

Treatment Options

Treatment focuses on promoting fracture healing and addressing nonunion. Options may include immobilization with a cast or brace, surgical intervention to realign and stabilize the fracture (e.g., internal fixation), and bone grafting to stimulate healing. Physical therapy is often recommended to restore function and strength after healing.

Prognosis and Follow-Up

Prognosis depends on the severity of the fracture and the success of treatment. Nonunion may lead to long-term complications, such as growth disturbances or joint problems. Regular follow-up with imaging and clinical assessments is necessary to monitor healing and adjust treatment as needed. Long-term outcomes may vary, with some patients experiencing residual functional limitations.

Complications

• Growth plate damage: May result in limb length discrepancy or angular deformity.
• Joint instability: Due to disruption of the epiphysis or metaphysis.
• Chronic pain: Persistent discomfort at the fracture site.
• Arthritis: Increased risk of degenerative joint changes over time.
• Nonunion: Failure of the fracture to heal, requiring additional intervention.

Lifestyle & Prevention

• Avoid high-impact activities until cleared by a healthcare provider.
• Use protective gear during sports to reduce injury risk.
• Maintain a balanced diet rich in calcium and vitamin D to support bone health.
• Follow post-treatment guidelines for activity restrictions and rehabilitation.

When to Seek Professional Help

Seek medical attention if pain worsens, swelling increases, or there is new deformity. Persistent inability to bear weight or signs of infection (e.g., fever, redness) also warrant prompt evaluation. Follow-up with an orthopedic specialist is recommended for ongoing management of nonunion.

Tips for Medical Coders

This code is used for a subsequent encounter for a Salter-Harris Type IV physeal fracture of the lower femur with nonunion. Documentation should specify the fracture type, location (unspecified femur), encounter type (subsequent), and the presence of nonunion. Ensure clinical notes support the nonunion diagnosis and subsequent encounter status to justify code assignment.