S82.846 Nondisplaced bimalleolar fracture of unspecified lower leg

Name of the Condition

• Nondisplaced bimalleolar fracture of unspecified lower leg
• ICD-10 Code: S82.846

Summary

A nondisplaced bimalleolar fracture of the unspecified lower leg involves a break in both the medial (inner) and lateral (outer) malleoli, the bony prominences at the distal end of the tibia and fibula. The fracture fragments remain in their normal alignment, preserving the structural integrity of the ankle joint. This injury typically results from trauma and may cause temporary instability due to the involvement of both bones.

Causes

Nondisplaced bimalleolar fractures commonly result from high-impact trauma, such as falls, motor vehicle accidents, or sports-related injuries. Direct force to the ankle, particularly when the foot is in a fixed position, can cause both malleoli to fracture without displacement. Twisting or rotational forces may also contribute to this type of injury.

Risk Factors

• Participation in activities with a high risk of ankle trauma, such as contact sports or skiing.
• Advanced age, which may lead to decreased bone density and increased fracture susceptibility.
• Conditions that weaken bone structure, such as osteoporosis or metabolic disorders.
• Previous ankle injuries or surgeries that compromise joint stability.

Symptoms

• Severe pain, swelling, and bruising around the ankle.
• Inability to bear weight on the affected leg.
• Tenderness and localized swelling at the malleoli.
• Possible audible snap or pop at the time of injury.

Diagnosis

Diagnosis begins with a physical examination to assess pain, swelling, and deformity. Imaging, such as X-rays, confirms the fracture and verifies the absence of displacement. CT or MRI may be used for detailed visualization of complex injuries or associated soft tissue damage.

Treatment Options

Treatment typically involves immobilization with a cast or brace to allow healing. Non-weight-bearing status may be recommended initially. Pain management and physical therapy are often included in the recovery plan. Surgical intervention is rarely needed for nondisplaced fractures unless instability is present.

Prognosis and Follow-Up

Prognosis is generally favorable with proper immobilization and adherence to weight-bearing restrictions. Follow-up appointments monitor healing progress, and physical therapy may be prescribed to restore strength and mobility. Most patients recover fully within 6–12 weeks, depending on fracture severity and individual factors.

Complications

• Delayed union or nonunion of the fracture.
• Post-traumatic arthritis due to joint damage.
• Chronic ankle instability or stiffness.
• Nerve or vascular injury in severe cases.

Lifestyle & Prevention

• Wear appropriate footwear for activities to reduce fall risk.
• Maintain bone health through calcium and vitamin D intake.
• Avoid high-impact activities without proper conditioning.
• Use protective gear during sports or high-risk activities.

When to Seek Professional Help

Seek immediate medical attention if severe pain, swelling, or deformity occurs after an injury. Persistent inability to bear weight or signs of infection (e.g., fever, redness) also warrant prompt evaluation.

Tips for Medical Coders

Document the absence of displacement and specify the lower leg as "unspecified" when coding. Ensure clinical notes confirm both malleoli are involved and no displacement is present to support the S82.846 code. Include details on trauma mechanism and imaging results for accurate coding.