S79.139K Salter-Harris Type III physeal fracture of lower end of unspecified femur, subsequent encounter for fracture with nonunion

Name of the Condition

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

Summary

A Salter-Harris Type III 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 extends through the epiphysis, as defined by the Salter-Harris classification system. The injury involves a fracture line that passes through the growth plate and into the epiphyseal bone, potentially affecting joint stability and future growth. This code specifically denotes a subsequent encounter for a fracture with nonunion, indicating the fracture has not healed properly after previous treatment.

Causes

Salter-Harris Type III 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 extend into the epiphysis. In some cases, repetitive stress or overuse may contribute to the injury, particularly in active children or adolescents. Nonunion may result from inadequate immobilization, poor blood supply, or excessive movement during healing.

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 alignment may predispose to fracture.
• Previous injury: Prior fractures or growth plate damage can increase nonunion risk.

Symptoms

• Pain localized to the knee or thigh, often worsening with movement.
• Swelling and bruising around the affected area.
• Limited range of motion in the knee joint.
• Visible deformity or abnormal positioning of the leg.
• Persistent pain or instability despite prior treatment.

Diagnosis

Diagnosis involves a thorough clinical evaluation, including a detailed history of the injury and symptoms. Physical examination assesses pain, swelling, and range of motion. Imaging studies, such as X-rays or MRI, are typically used to confirm the fracture type, assess healing progress, and identify nonunion. The presence of a persistent fracture line or lack of callus formation on imaging supports a nonunion diagnosis.

Treatment Options

Treatment focuses on promoting fracture healing and restoring function. Options may include:

• Immobilization with a cast or brace to stabilize the fracture.
• Surgical intervention, such as internal fixation, to realign and stabilize the bone.
• Bone grafting to stimulate healing in cases of nonunion.
• Physical therapy to restore strength and mobility after healing.

Prognosis and Follow-Up

Prognosis depends on the severity of the fracture, timing of treatment, and adherence to follow-up care. Early intervention improves outcomes, but nonunion may require extended treatment. Regular follow-up with imaging and clinical assessments is necessary to monitor healing and adjust treatment plans. Long-term monitoring for growth disturbances or joint issues may be needed.

Complications

• Nonunion or delayed union, requiring additional intervention.
• Growth plate damage leading to limb length discrepancy or angular deformity.
• Joint stiffness or reduced range of motion.
• Chronic pain or instability in the affected knee.
• Infection or other surgical complications if intervention is required.

Lifestyle & Prevention

• Avoid high-impact activities until cleared by a healthcare provider.
• Use protective gear during sports or activities with fall risks.
• Maintain a balanced diet rich in calcium and vitamin D to support bone health.
• Follow post-treatment guidelines for immobilization and activity restrictions.
• Attend all scheduled follow-up appointments to monitor healing.

When to Seek Professional Help

Seek immediate medical attention if experiencing:

• Severe or worsening pain.
• Increased swelling, bruising, or deformity.
• Inability to bear weight or move the leg.
• Signs of infection, such as fever, redness, or drainage.
• Persistent symptoms despite prior treatment.

Tips for Medical Coders

This code (S79.139K) is used for a subsequent encounter for a Salter-Harris Type III 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, as this is a key component of the code. Verify that prior treatment and lack of healing are clearly documented to justify the subsequent encounter.