S82.866 Nondisplaced Maisonneuve's fracture of unspecified leg

Name of the Condition

• Nondisplaced Maisonneuve's fracture of unspecified leg
• ICD-10 Code: S82.866

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 in their normal alignment. This injury typically results from rotational forces applied to the ankle, commonly seen in trauma such as falls or sports injuries.

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.

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.

Symptoms

• 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."
• Bruising or tenderness along the lower leg.

Diagnosis

Diagnosis involves a physical examination to assess ankle stability, tenderness, and swelling. Imaging, typically X-rays, is used to identify the proximal fibula fracture and associated injuries. Additional imaging, such as CT or MRI, may be required to evaluate soft tissue damage or confirm the nondisplaced nature of the fracture.

Treatment Options

Treatment depends on the severity of the injury and associated ligament damage. Nondisplaced fractures may be managed with immobilization (e.g., casting or bracing) and restricted weight-bearing. Surgical intervention may be necessary if there is significant syndesmotic instability or associated fractures. Physical therapy is often recommended to restore strength and mobility.

Prognosis and Follow-Up

With appropriate treatment, most patients recover fully, though recovery time may vary. Follow-up care typically includes monitoring for healing progress and gradual return to activity. Long-term outcomes depend on the extent of ligament damage and adherence to rehabilitation protocols.

Complications

Potential complications include chronic ankle instability, post-traumatic arthritis, or delayed union of the fracture. In rare cases, malunion or nonunion of the fibula may occur, requiring additional intervention.

Lifestyle & Prevention

• Wear supportive footwear appropriate for activity.
• Avoid uneven surfaces or hazardous environments.
• Engage in exercises to strengthen ankle muscles and improve balance.
• Use proper techniques during sports or high-risk activities to reduce rotational stress.

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., fever, increased swelling, redness). Persistent instability or pain after initial treatment also warrants evaluation.

Tips for Medical Coders

Document the nondisplaced nature of the Maisonneuve's fracture and specify the leg (unspecified in this code) in the medical record. Ensure associated injuries (e.g., syndesmotic ligament tears, medial malleolus damage) are clearly noted, as these may impact coding and reimbursement. Use clinical terms consistent with the injury mechanism and anatomical location for accurate code assignment.