S82.862K Displaced Maisonneuve's fracture of left leg, subsequent encounter for closed fracture with nonunion

Name of the Condition

• Displaced Maisonneuve's fracture of left leg, subsequent encounter for closed fracture with nonunion

Summary

A Maisonneuve's fracture is a specific type of ankle injury involving a displaced fracture of the proximal fibula (upper portion of the smaller lower leg bone) on the left side, combined with a tear of the tibiofibular syndesmosis and often associated injuries to the medial structures of the ankle. The term "displaced" indicates that the fractured bone fragments are not aligned properly. This code represents a subsequent encounter for treatment, meaning the patient is receiving ongoing care for a closed fracture (skin remains intact) that has failed to heal (nonunion) after an initial period of treatment. The injury typically results from rotational forces applied to the ankle, leading to joint instability.

Causes

Maisonneuve's fractures are caused by external rotational forces applied to the ankle, such as twisting or turning. Common scenarios include falls, sports-related injuries, or trauma where the foot is planted and the body rotates forcefully. The rotational force disrupts the syndesmotic ligaments and may cause additional damage to the medial malleolus or deltoid ligament. The nonunion aspect indicates that the fracture did not heal properly during prior treatment, often due to inadequate immobilization, poor blood supply, or excessive motion at the fracture site.

Risk Factors

• Participation in high-impact sports or activities with sudden directional changes.
• Previous ankle injuries or ligamentous instability.
• Traumatic events involving rotational forces to the ankle.
• Factors affecting bone healing, such as smoking, diabetes, or nutritional deficiencies.
• Inadequate initial treatment or immobilization of the fracture.

Symptoms

• Persistent pain and swelling around the ankle, even after initial treatment.
• Difficulty bearing weight or walking on the affected leg.
• Visible deformity or misalignment of the ankle joint.
• Limited range of motion in the ankle or subtalar joint.
• Sensation of instability or "giving way" when bearing weight.

Diagnosis

Diagnosis involves a combination of clinical evaluation and imaging studies. A physical examination may reveal tenderness, swelling, or deformity around the ankle. Imaging typically includes X-rays to assess the fracture alignment and healing status, with additional views of the proximal fibula and ankle mortise. If nonunion is suspected, advanced imaging such as CT scans or MRI may be used to evaluate bone healing and soft tissue integrity. The "subsequent encounter" designation confirms ongoing treatment for a previously diagnosed fracture, while "nonunion" is documented when healing has not occurred within the expected timeframe (usually 3-6 months).

Treatment Options

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

• Prolonged immobilization with a cast or brace to reduce motion at the fracture site.
• Surgical intervention, such as open reduction and internal fixation (ORIF) with plates or screws, to realign and stabilize the fracture.
• Bone grafting to stimulate healing in cases of nonunion.
• Physical therapy to restore strength, range of motion, and functional mobility once healing is underway.
• Pain management and activity modification to avoid further stress on the healing bone.

Prognosis and Follow-Up

Prognosis depends on the severity of the fracture, the success of treatment, and the patient's overall health. Nonunion fractures may require extended treatment and rehabilitation. Regular follow-up appointments are necessary to monitor healing progress, typically with repeat imaging at intervals. Full recovery can take several months, and some patients may experience long-term ankle instability or reduced mobility. Adherence to treatment plans and activity restrictions is critical to optimize outcomes.

Complications

• Persistent nonunion or delayed healing requiring additional intervention.
• Chronic ankle pain or instability.
• Post-traumatic arthritis due to joint damage.
• Infection (rare, but possible with surgical intervention).
• Nerve or blood vessel damage in severe cases.
• Reduced functional ability, particularly in weight-bearing activities.

Lifestyle & Prevention

• Avoid high-risk activities that involve sudden rotational forces until fully healed.
• Use proper footwear and supportive devices (e.g., braces) to stabilize the ankle.
• Maintain a healthy diet rich in calcium and vitamin D to support bone healing.
• Follow rehabilitation guidelines to restore strength and mobility.
• Address underlying risk factors, such as smoking or poor nutrition, to improve healing potential.

When to Seek Professional Help

Seek immediate medical attention if you experience:

• Sudden, severe pain or swelling in the ankle.
• Inability to bear weight on the affected leg.
• Visible deformity or misalignment of the ankle.
• Signs of infection, such as redness, warmth, or drainage.
• Worsening pain or instability despite prior treatment.

Tips for Medical Coders

This code is used for a displaced Maisonneuve's fracture of the left leg during a subsequent encounter for a closed fracture with nonunion. Document the encounter type (subsequent) and the presence of nonunion clearly in the medical record. Ensure the fracture is confirmed as closed (skin intact) and that the nonunion is clinically documented or supported by imaging. The "subsequent encounter" modifier indicates ongoing care for a condition with inadequate response to prior treatment, and the "nonunion" designation requires evidence of failed healing. Accurate documentation of the fracture location (left leg), displacement, and encounter type is essential for correct coding.