A Case of Neglected Achilles Rupture after an Ankle Sprain.

Lateral ankle sprains are common injuries seen by primary care and podiatric specialties. However, lateral ankle pain from a suspected inversion injury of the ankle may be more than a Grades I, II, or III ankle sprain. This case report illustrates a 30-year-old U.S. Navy Active Duty Service Member that was initially diagnosed with a "lateral ankle sprain". Upon subsequent follow-up with a podiatric foot and ankle surgeon, he was diagnosed with a 3-month-old chronic and neglected Achilles tendon rupture. The purpose of this manuscript is to present an uncommon and unique presentation of lateral ankle pain after injury, subsequent surgical treatment, as well as a review of the common differential diagnoses of "lateral ankle pain."