S66.391 Other injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level

Name of the Condition

• Other injury of extensor muscle, fascia and tendon of left index finger at wrist and hand level
• ICD-10 Code: S66.391

Summary

This condition involves damage to the extensor muscle, fascia, and tendon of the left index finger at the wrist and hand level. It typically results from trauma or overuse affecting these structures, which are critical for finger extension and hand function.

Causes

Common causes include acute trauma (e.g., falls, direct blows), repetitive strain from activities requiring finger extension, or lacerations that disrupt the tendon or muscle. Penetrating injuries or sudden forceful movements may also lead to this injury.

Risk Factors

• Repetitive hand or finger movements (e.g., typing, gripping tools).
• Participation in sports with high finger strain (e.g., rock climbing, racquet sports).
• Previous finger or hand injuries.
• Occupational tasks involving manual labor or fine motor skills.

Symptoms

• Pain, swelling, or tenderness along the finger or wrist.
• Difficulty extending the finger or gripping objects.
• Bruising or visible deformity at the injury site.
• Weakness or loss of finger function.

Diagnosis

Physical examination to assess range of motion, strength, and tenderness. Imaging (e.g., X-rays, MRI) to evaluate tendon integrity, muscle damage, or associated fractures.

Treatment Options

Treatment may include rest, immobilization with a splint, physical therapy to restore function, and pain management. Severe cases may require surgical repair of the tendon or muscle.

Prognosis and Follow-Up

Prognosis depends on the extent of injury and timely treatment. Most patients recover with appropriate care, but follow-up is important to monitor healing and prevent long-term stiffness or weakness.

Complications

Potential complications include chronic pain, reduced finger mobility, tendon re-rupture, or infection if the injury is open.

Lifestyle & Prevention

Avoid repetitive or forceful finger movements, use ergonomic tools, and wear protective gear during high-risk activities. Strengthening exercises may help prevent future injuries.

When to Seek Professional Help

Seek medical attention if pain is severe, function is significantly impaired, or there is visible deformity or open wound.

Tips for Medical Coders

Document the specific finger (left index) and injury type (extensor muscle, fascia, tendon) to ensure accurate coding. Include details on trauma mechanism, treatment, and encounter type (e.g., initial, subsequent) for complete documentation.