Arthroscopic Treatment of a Displaced Nonunion of the Anterior Inferior Iliac Spine Causing Extra-articular Impingement

Abstract

This report describes a case of nonunion of an anterior inferior iliac spine (AIIS) apophyseal avulsion fracture with resultant subspine impingement combined with symptomatic femoroacetabular impingement (FAI). A 16-year-old male soccer player presented with a 6-month history of right groin pain exacerbated by kicking and running. The patient was diagnosed with a displaced nonunion of the AIIS apophysis avulsion fracture causing secondary extra-articular impingement beyond cam-type FAI by physical examination and radiological findings. The authors performed arthroscopic AIIS decompression, with concurrent FAI correction and labral repair and capsular closure. At 4 months after surgery, a radiograph and a computed tomography scan showed complete bony union of the AIIS apophyseal nonunion. Modified Harris Hip Sore and Nonarthritic Hip Score improved from 74.8 and 61, respectively, to 100 for both at final follow-up. The effectiveness of arthroscopic decompression of the AIIS as part of a comprehensive minimally invasive surgery including FAI correction and labral repair resulted in complete union of the AIIS and pain-free return to sport and bony union. [Orthopedics. 2017; 40(4):e725-e728.].