S82.865K Nondisplaced Maisonneuve's fracture of left leg, subsequent encounter for closed fracture with nonunion

Name of the Condition

• Nondisplaced 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 fracture of the proximal fibula (upper portion of the smaller lower leg bone) combined with a tear of the syndesmotic ligaments and often an associated injury to the medial malleolus or deltoid ligament. The term "nondisplaced" indicates that the fractured bone fragments remain aligned. This injury typically results from rotational forces applied to the ankle, commonly seen in trauma such as falls or sports injuries. The "subsequent encounter for closed fracture with nonunion" specifies this is a follow-up visit for a fracture that has not healed properly, with no open wound present.

Causes

The fracture is caused by external rotational forces applied to the ankle, often during activities that involve twisting or turning. Common scenarios include falls, motor vehicle accidents, or sports-related impacts where the foot is planted and the body rotates forcefully. The mechanism typically involves the talus rotating outward, stressing the syndesmotic ligaments and causing the proximal fibula to fracture. Nonunion may occur due to inadequate immobilization, poor blood supply, or excessive movement at the fracture site during healing.

Risk Factors

• Participation in activities with high rotational stress on the ankle, such as soccer or basketball.
• Previous ankle injuries or ligamentous instability.
• Improper footwear or uneven terrain increasing fall risk.
• Age-related factors that may affect bone density or ligament integrity.
• Smoking or other conditions that impair bone healing.

Symptoms

• Persistent pain and swelling localized to the proximal fibula and ankle.
• Difficulty bearing weight on the affected leg.
• Instability or a feeling of the ankle "giving way."
• Possible visible deformity if the fracture has displaced (though nondisplaced here).
• Delayed healing or persistent symptoms despite prior treatment.

Diagnosis

Diagnosis typically involves a physical examination to assess pain, swelling, and stability, followed by imaging studies. X-rays are used to confirm the fracture and assess alignment, while CT or MRI may be ordered to evaluate for nonunion or associated ligament damage. The "subsequent encounter" status indicates the patient has a history of this injury, and the "nonunion" designation is confirmed by imaging showing no bridging bone across the fracture site after an appropriate healing period.

Treatment Options

Treatment focuses on promoting healing of the nonunion and restoring ankle stability. Options may include immobilization with a cast or brace, physical therapy to strengthen surrounding muscles, or surgical intervention such as internal fixation with plates or screws. The choice depends on the severity of the nonunion, patient activity level, and overall health. Follow-up imaging is used to monitor progress.

Prognosis and Follow-Up

Prognosis varies based on the success of treatment and the patient's adherence to rehabilitation. Nonunion may require extended healing time or additional procedures. Regular follow-up appointments are necessary to assess healing and adjust treatment plans. Most patients can return to normal activities, but some may experience long-term ankle instability or arthritis.

Complications

• Chronic pain or instability in the ankle.
• Development of post-traumatic arthritis.
• Need for additional surgery if nonunion persists.
• Nerve or blood vessel damage in severe cases.
• Reduced mobility or functional limitations.

Lifestyle & Prevention

• Wear supportive footwear and use ankle braces during high-risk activities.
• Maintain a healthy weight to reduce stress on the ankle.
• Engage in exercises to strengthen ankle muscles and improve balance.
• Avoid activities that place excessive rotational stress on the ankle until fully healed.
• Follow post-treatment guidelines closely to minimize nonunion risk.

When to Seek Professional Help

Seek immediate medical attention if you experience severe pain, inability to bear weight, visible deformity, or signs of infection (e.g., redness, fever) at the fracture site. Contact your healthcare provider if symptoms worsen or do not improve with treatment, or if you notice persistent instability or swelling.

Tips for Medical Coders

Document the encounter as a "subsequent" visit for a closed fracture with nonunion, ensuring the left leg and Maisonneuve's fracture specifics are clearly noted. Include details on prior treatments, imaging results confirming nonunion, and any surgical or conservative management plans. Verify that the fracture remains nondisplaced and no open wound is present to justify the code.