Entrapment and compression of peripheral nerves of the lower extremities, such as the sural nerve, are known to be infrequent sequelae of injuries resulting from exercise, posture, or footwear. Although testing for Tinel's sign and nerve conduction velocity examinations contribute to an accurate diagnosis, the use of high-resolution ultrasonography is preferred, not only because of its cost-effectiveness and non-invasive dynamic capacity, but also because of difficulty in differential diagnosis due to the overlapping sensory distribution of peripheral nerves. This report describes the use of high-resolution ultrasonography and nerve conduction examination of the sural nerve in a case of sural neuritis attributed to a sports-related ankle sprain.