S83.015 Lateral dislocation of left patella

Name of the Condition

• Lateral Dislocation of Left Patella

Summary

Lateral dislocation of the left patella occurs when the kneecap moves completely out of its normal position, typically shifting toward the outer side of the knee. This condition can cause pain, instability, and functional impairment in the affected joint.

Causes

The condition is often caused by trauma, such as a direct blow or sudden twisting of the knee, or by structural abnormalities like a shallow femoral groove or ligament laxity. Muscle imbalances or weakness in the quadriceps may also contribute.

Risk Factors

• Participation in high-impact sports (e.g., basketball, soccer)
• Anatomical factors (e.g., patellar alta, abnormal knee alignment)
• Previous knee injuries or dislocations
• Weakness in quadriceps or hip muscles

Symptoms

• Sudden knee pain, often with a popping sensation
• Visible or palpable displacement of the kneecap
• Swelling and bruising around the knee
• A feeling of instability or the knee "giving way"
• Difficulty bearing weight or straightening the leg

Diagnosis

Diagnosis typically involves a physical examination to assess patellar alignment and stability. Imaging studies, such as X-rays or MRI, may be used to evaluate joint structure and rule out fractures or other injuries.

Treatment Options

• Nonsurgical: Rest, ice, compression, and elevation (RICE); knee brace immobilization; physical therapy to strengthen supporting muscles.
• Surgical: Procedures to realign the patella or repair damaged ligaments, if conservative measures fail or for recurrent dislocations.

Prognosis and Follow-Up

Prognosis depends on the severity of the injury and adherence to treatment. Most patients recover with proper care, but some may experience long-term instability. Follow-up appointments monitor healing and functional recovery, with physical therapy often recommended to prevent recurrence.

Complications

• Recurrent dislocations
• Chronic knee instability
• Arthritis or joint damage over time
• Nerve or blood vessel injury (rare)

Lifestyle & Prevention

• Strengthen quadriceps and hip muscles through targeted exercises.
• Use proper footwear and avoid high-impact activities that strain the knee.
• Maintain a healthy weight to reduce joint stress.
• Consider bracing during sports or activities with a high risk of knee injury.

When to Seek Professional Help

Seek immediate medical attention if the kneecap is visibly displaced, severe pain or swelling occurs, or the knee cannot bear weight. Prompt care can prevent complications and improve outcomes.

Tips for Medical Coders

Document the laterality (left) and the complete dislocation (not subluxation) to ensure accurate coding. Include details on trauma, structural abnormalities, or prior injuries if relevant to support the diagnosis.