Gluteal activation during squatting reduces acetabular contact pressure in persons with femoroacetabular impingement syndrome: A patient-specific finite element analysis

• Published in: Clinical biomechanics (Bristol) 2023-01, Vol.101, p.105849-105849, Article 105849
• Main Authors: Cannon, Jordan, Kulig, Kornelia, Weber, Alexander E., Powers, Christopher M.
• Format: Article
• Language: English
• Subjects: Acetabulum; Cam morphology; Female; Femoracetabular Impingement; Femoroacetabular impingement syndrome; Finite Element Analysis; Gluteus maximus; Gluteus medius; Hip; Hip internal rotation; Hip Joint; Humans; Male; Patient-specific models; Range of Motion, Articular - physiology
• ISSN: 0268-0033; 1879-1271
• DOI: 10.1016/j.clinbiomech.2022.105849

Femoroacetabular impingement syndrome is a motion-related clinical disorder resulting from abnormal hip joint morphology. Mechanical impingement, in which the aspherical femoral head (cam morphology) abuts with the acetabular rim, is created with simultaneous hip flexion, internal rotation, and adduction. Impaired function of the gluteal muscles may be contributory to femoroacetabular impingement syndrome progression. The purpose of this study was to assess the influence of gluteal muscle recruitment on acetabular contact pressure during squatting in persons with cam femoroacetabular impingement syndrome. Eight individuals (4 males, 4 females) with a diagnosis of cam femoroacetabular impingement syndrome underwent CT imaging of the pelvis and proximal femora, and a biomechanical assessment of squatting (kinematics, kinetics, and electromyography). Two maximal depth bodyweight squat conditions were evaluated: 1) non-cued squatting; and 2) cued gluteal activation squatting. Utilizing subject-specific electromyography-driven hip and finite element modeling approaches, hip muscle activation, kinematics, bone-on-bone contact forces, and peak acetabular contact pressure were compared between squat conditions. Modest increases in gluteus maximus (7% MVIC, P