Atraumatic Pyogenic Extensor Tenosynovitis of the Extensor Digitorum Longus.

Area of Science:

• Orthopedics
• Infectious Disease

Background:

• Pyogenic tenosynovitis typically affects flexor tendons, with extensor involvement being rare, particularly in the lower extremities.
• Extensor pyogenic tenosynovitis cases are often linked to atypical pathogens or trauma, with limited reports in the foot.

Observation:

• A 22-year-old male presented with acute dorsolateral foot pain, erythema, and swelling.
• The patient had no history of trauma, intravenous drug use, or significant comorbidities.
• Clinical examination and ultrasound confirmed extensor tenosynovitis of the extensor digitorum longus tendon.

Findings:

• The patient was treated with intravenous antibiotics and surgical irrigation and debridement.
• Intraoperative findings revealed a significant phlegmon within the tenosynovium.
• Post-treatment, the patient experienced symptom resolution and a full recovery without deficits.

Implications:

• Pyogenic extensor tenosynovitis should be considered in the differential diagnosis of isolated dorsolateral foot inflammation.
• This case underscores the importance of considering this diagnosis even in the absence of typical risk factors like trauma or IV drug use.