Differential Diagnosis for Ankle Pain
Single Most Likely Diagnosis
- Ankle Sprain: This is the most common cause of ankle pain, especially in individuals who participate in sports or activities that involve running or jumping. The mechanism of injury typically involves inversion of the ankle, leading to stretching or tearing of the lateral ligaments.
Other Likely Diagnoses
- Achilles Tendinitis: Inflammation of the Achilles tendon, which connects the calf muscles to the heel bone, can cause pain in the back of the ankle. This condition is common in runners and athletes who suddenly increase their activity level.
- Plantar Fasciitis: Although this condition primarily affects the heel, it can also cause pain that radiates to the ankle. It is characterized by inflammation of the plantar fascia, a band of tissue that supports the arch of the foot.
- Osteoarthritis: Wear and tear of the ankle joint can lead to osteoarthritis, causing pain, stiffness, and limited mobility. This condition is more common in older adults.
Do Not Miss Diagnoses
- Fracture: It is crucial to rule out a fracture, especially if the pain follows a traumatic event. A fracture can be life-altering if not properly treated, and some fractures, like those involving the ankle joint, may require surgical intervention.
- Septic Arthritis: Bacterial infection of the ankle joint is a medical emergency that requires prompt antibiotic treatment and possibly surgical drainage. Delayed diagnosis can lead to severe joint damage and systemic infection.
- Deep Vein Thrombosis (DVT): Although DVT typically presents with calf pain and swelling, it can occasionally cause ankle pain. DVT is a serious condition that can lead to pulmonary embolism if not treated.
Rare Diagnoses
- Gout: A form of arthritis characterized by sudden, severe attacks of pain, swelling, redness, and tenderness, often occurring at the base of the big toe but can also affect the ankle. It is caused by elevated levels of uric acid in the blood.
- Pseudogout (Calcium Pyrophosphate Deposition Disease, CPPD): Similar to gout, pseudogout causes sudden, severe joint pain, but it is due to calcium pyrophosphate dihydrate crystal deposition within the joint. The knee is most commonly affected, but it can also occur in the ankle.
- Osteochondritis Dissecans: A joint condition in which a piece of cartilage, along with a thin layer of the bone beneath it, comes loose from the end of a bone because of inadequate blood supply. It can occur in any joint but is most common in the knee, elbow, and ankle.