The ankle sprain is often thought of as an injury involving only the lateral ankle ligaments. Frequently other structures are also injured. However, the literature describes only some of the associated injuries. The authors feel that a thorough analysis of each structure injured with the inversion and eversion ankle sprain along with the incidence would be invaluable in making an accurate diagnosis and providing appropriate treatment. The authors conducted a prospective study using a standardized evaluation during the initial examination of patients reporting with an ankle sprain. Over a 33-month period, 639 patients were studied at Oakwood Hospital Downriver Center Emergency Room and Occupational Medicine Clinic. Of the 639 patients, 92 had an associated avulsion or compression fracture of the foot or ankle. Of the remaining 547 patients, the anterior talofibular ligament was injured 453 times, the calcaneal fibular ligament was injured 366 times, and the posterior talofibular ligament was injured 187 times. Injuries to the ankle joint capsule were noted in 180 cases, the extensor digitorum brevis was involved in 111 cases, the sinus tarsi was involved in 88 cases, the peroneal tendons in 83 cases, the Achilles tendon in 67 cases, the calcaneal-cuboid ligament in 41 cases, and the syndesmosis was injured in 31 cases. Additionally, neuritis was seen in 80 patients presenting with a sprained ankle. Because of the varied and multiple components to the common sprained ankle, the authors feel that this condition would more appropriately be designated as the sprained ankle syndrome. The findings of this study may aid the examiner in exploring a more knowledgeable approach in evaluation, leading to an accurate diagnosis and appropriate treatment.