Laura E Diamond1, Kim L Bennell, Tim V Wrigley, Rana S Hinman, John Oʼdonnell, Paul W Hodges. 1. 1School of Allied Health Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, AUSTRALIA; 2Department of Physiotherapy, School of Health Sciences, Centre for Health, Exercise and Sports Medicine, The University of Melbourne, Parkville, AUSTRALIA; 3St Vincent's Hospital, East Melbourne, AUSTRALIA; and 4School of Health and Rehabilitation Sciences, Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, The University of Queensland, Brisbane, QLD, AUSTRALIA.
Abstract
PURPOSE: Identification of the biomechanical alterations in individuals with symptomatic femoroacetabular impingement (FAI) is critical to understand the pathology and inform treatments. Yet hip function in this condition is poorly defined. Squatting requires large hip flexion range and involves motion toward the position of hip impingement; thus, it is likely to expose modified biomechanics in these individuals. This study aimed to determine whether hip and pelvis biomechanics differ between individuals with and without symptomatic FAI during an unconstrained deep squat and a constrained squat designed to limit compensation by the pelvis and trunk. METHODS: Fifteen participants with symptomatic cam-type or combined (cam plus pincer) FAI who were scheduled for arthroscopic surgery and 14 age- and sex-matched controls without FAI underwent three-dimensional motion analysis during the two squatting tasks. Trunk, pelvis, and hip kinematics and hip kinetics were compared between groups. RESULTS: There were no between-group differences in normalized squat depth for either task. Descent speed was slower for the FAI group during the unconstrained squat (P < 0.05). During the constrained squat, individuals with FAI demonstrated greater pelvic rise (P = 0.01) and hip adduction (P = 0.04) on the symptomatic side than controls. The hip external rotation moment was less in FAI patients during descent (P = 0.04), as was transverse plane hip angle variability (P = 0.04). CONCLUSIONS: Individuals with symptomatic FAI can squat to a depth comparable with controls, regardless of task design. When the task is constrained, FAI patients demonstrate greater ipsilateral pelvic rise and maintain a more adducted hip position, which may coincide with a compensatory strategy to avoid end range flexion as the hip approaches impingement. These biomechanical alterations may put additional stress on adjacent regions and have relevance for rehabilitation.
PURPOSE: Identification of the biomechanical alterations in individuals with symptomatic femoroacetabular impingement (FAI) is critical to understand the pathology and inform treatments. Yet hip function in this condition is poorly defined. Squatting requires large hip flexion range and involves motion toward the position of hip impingement; thus, it is likely to expose modified biomechanics in these individuals. This study aimed to determine whether hip and pelvis biomechanics differ between individuals with and without symptomatic FAI during an unconstrained deep squat and a constrained squat designed to limit compensation by the pelvis and trunk. METHODS: Fifteen participants with symptomatic cam-type or combined (cam plus pincer) FAI who were scheduled for arthroscopic surgery and 14 age- and sex-matched controls without FAI underwent three-dimensional motion analysis during the two squatting tasks. Trunk, pelvis, and hip kinematics and hip kinetics were compared between groups. RESULTS: There were no between-group differences in normalized squat depth for either task. Descent speed was slower for the FAI group during the unconstrained squat (P < 0.05). During the constrained squat, individuals with FAI demonstrated greater pelvic rise (P = 0.01) and hip adduction (P = 0.04) on the symptomatic side than controls. The hip external rotation moment was less in FAI patients during descent (P = 0.04), as was transverse plane hip angle variability (P = 0.04). CONCLUSIONS: Individuals with symptomatic FAI can squat to a depth comparable with controls, regardless of task design. When the task is constrained, FAI patients demonstrate greater ipsilateral pelvic rise and maintain a more adducted hip position, which may coincide with a compensatory strategy to avoid end range flexion as the hip approaches impingement. These biomechanical alterations may put additional stress on adjacent regions and have relevance for rehabilitation.
Authors: Lindsey Brown-Taylor; Brittany Schroeder; Cara L Lewis; Jennifer Perry; Timothy E Hewett; John Ryan; Stephanie Di Stasi Journal: J Orthop Res Date: 2020-04-13 Impact factor: 3.494
Authors: Davor Vasiljevic; Gretchen B Salsich; Darrah Snozek; Bradley Aubin; Stefanie N Foster; Michael J Mueller; John C Clohisy; Marcie Harris-Hayes Journal: Physiother Theory Pract Date: 2018-07-02 Impact factor: 2.279
Authors: Gregory L Cvetanovich; Gary J Farkas; Edward C Beck; Philip Malloy; Kyleen Jan; Alejandro Espinoza-Orias; Shane J Nho Journal: J Hip Preserv Surg Date: 2020-02-18