Differential Diagnosis for Left Ankle Pain over ATFL
Single Most Likely Diagnosis
- Peroneal Tendinopathy: This condition is characterized by inflammation or degeneration of the peroneal tendons, which run along the lateral aspect of the ankle and behind the lateral malleolus. The pain pattern described, radiating up the fibula, is consistent with peroneal tendinopathy, especially given the absence of a reported injury.
Other Likely Diagnoses
- Lateral Ankle Impingement: This condition can cause pain on the lateral side of the ankle, similar to the pain described. It often results from repetitive activities or chronic ankle instability, which could be a factor even without a specific injury.
- Ankle Synovitis: Inflammation of the synovial lining of the ankle joint can cause pain and may be localized to the lateral aspect, depending on the extent of inflammation and the specific areas affected.
- Fibular Stress Fracture: Although less common without a history of injury, stress fractures can occur due to repetitive stress or overuse, especially in individuals with predisposing factors such as osteoporosis or certain athletic activities.
Do Not Miss Diagnoses
- Osteonecrosis of the Talus or Fibula: Although rare, osteonecrosis (avascular necrosis) of the bones in the ankle can cause severe pain and requires prompt diagnosis to prevent further bone collapse and potential need for surgical intervention.
- Infection (Osteomyelitis or Septic Arthritis): Infections in the bone or joint can present with pain and may not always have a clear history of trauma or infection source. Early diagnosis is crucial for effective treatment.
- Tumor: Bone or soft tissue tumors can cause localized pain and should be considered, especially if the pain is persistent, worsening, or accompanied by other systemic symptoms.
Rare Diagnoses
- Nerve Entrapment (Superficial Peroneal Nerve): Entrapment of the superficial peroneal nerve can cause pain and numbness on the lateral aspect of the ankle and foot.
- Erythromelalgia: A rare disorder characterized by burning pain, heat, and redness in the hands and feet, which could potentially cause ankle pain.
- Complex Regional Pain Syndrome (CRPS): A chronic pain condition that can cause severe pain, inflammation, and sensitivity in one of the limbs after an injury or trauma, though it can rarely occur without a clear precipitating event.