The anterior inferior iliac spine (AIIS) avulsion fractures are uncommon, caused by a sudden contraction of the rectus femoris muscle with hyperextension of the hip and knee flexion. We present the clinical case of a 32-year-old mansuffering from pain in his right hip for several years with a history of a AIIS avulsion fracture in his childhood. He presented pain with flexion and internal rotation of the right hip. Physical examination and imaging tests revealed an extra-articular hip impingement secondary to a malunited fracture of AIIS. The patient underwent surgery performing AIIS osteoplasty and excision of the ossification by an anterior mini-open approach. After surgery he was able to re-join sports activity. Malunited fracture of AIIS can cause an extra-articular hip impingement in young sports patients. The treatment by surgical excision of the hypertrophic spine through an anterior mini-open approach allows the correction of the deformity and an early reincorporation to sports activities.