Differential Diagnosis for Ankle Pain

The patient presents with a two-week history of ankle pain following a rolling injury, with worsening pain at night. Here's a differential diagnosis organized into categories:

• Single Most Likely Diagnosis
  • Ankle sprain: The patient's history of rolling her ankle and subsequent pain is consistent with a sprain, which is a common injury that can cause sharp pain, especially with weight-bearing activities.
• Other Likely Diagnoses
  • Ankle fracture: Although the patient has been walking on her ankle, a fracture is still possible, especially if the pain is severe and worsening at night.
  • Peroneal tendonitis: The peroneal tendons run along the outside of the ankle and can become inflamed due to overuse or injury, causing sharp pain.
  • Achilles tendonitis: The Achilles tendon can also become inflamed due to overuse or injury, causing pain in the back of the ankle.
• Do Not Miss Diagnoses
  • Osteomyelitis: Although rare, osteomyelitis (bone infection) can occur after an ankle injury and cause severe pain, especially at night.
  • Septic arthritis: Bacterial infection of the ankle joint can cause severe pain, swelling, and redness, and requires prompt treatment.
  • Deep vein thrombosis (DVT): DVT can cause leg pain and swelling, and although less likely in a young patient, it's a potentially life-threatening condition that should not be missed.
• Rare Diagnoses
  • Stress fracture: A stress fracture can occur due to overuse or repetitive stress on the ankle bones, causing pain that worsens over time.
  • Ankle impingement: Ankle impingement occurs when soft tissue becomes trapped between the bones of the ankle joint, causing pain and limited mobility.
  • Neuroma: A neuroma is a benign growth of nerve tissue that can cause sharp pain, usually in the ball of the foot or between the toes, but can also occur in the ankle.