Do Acetabular Buttress Augment Pose Risk to the Superior Gluteal Nerve? A Cadaveric Study.

Background: Management of acetabular defects in total joint reconstruction can be challenging. Various algorithmic approaches have been developed, with some recommending using posterosuperior acetabular buttress augments for severe defects. The superior gluteal nerve lies in close proximity to their application, and damage to it results in deterioration of hip stability and gait mechanics. There has been investigation into the relationship of the superior gluteal nerve to various anatomic points. To our knowledge, no study exists examining the relationship between the acetabular rim and the superior gluteal nerve for the application of these particular devices.

Methods: Ten adult cadaver specimens were examined. A reproducible technique in relation to the typical placement of a buttress augment was used. From a distance of 20 millimeters (mm) lateral to the greater sciatic notch, the distance from the superior gluteal nerve to the posterosuperior acetabular rim was measured.

Results: The average distance between the posterosuperior acetabular rim and the superior gluteal nerve was found to be 52 mm, ranging from 48 mm to 60 mm.

Conclusion: With proprietary acetabular augments measuring up to 68 mm in length, the superior gluteal nerve could be at substantial risk with placement of these devices. Surgeons should take great care with dissection for and intraoperative placement of these devices, and particularly strive for optimized prosthetic hip stability to mitigate the risk of dislocation from nerve injury. To our knowledge, this study is the first of its kind and provides valuable anatomic and operative knowledge during these highly complex cases.