Short term outcomes of hip arthroscopy on hip joint mechanics and cartilage health in patients with femoroacetabular impingement syndrome

Abstract

Background: Femoroacetabular acetabular impingement syndrome (FAIS) consists of abnormal hip joint morphology resulting in painful hip joint impingement. Hip arthroscopy corrects the abnormal morphology and reduces clinical symptoms associated with FAIS yet the effects of hip arthroscopy on gait mechanics and cartilage health are not well understood. Methods:Ten FAIS patients and 10 matched healthy controls were recruited and underwent gait analysis consisting of 3D hip joint kinematics and kinetics. FAIS patients underwent gait analysis and quantitative magnetic resonance imaging of the surgical hip joint before and seven months after surgery. Patient reported outcomes (PRO) were used to quantify hip joint pain, function and quality of life and were obtained from all study participants.Findings: No significant differences were observed in hip joint kinematics or kinetics prior to surgery in the FAIS patients compared to healthy controls. After surgery, FAIS patients exhibited improved PRO, similar hip joint kinematic patterns, increased hip flexion moment impulse (HFMI) and decreased hip extension moment impulse within the surgical limb. FAIS patients that ambulated with increased HFMI after surgery demonstrated a decrease in posterior and anterior femoral T1ρ and T2 values.

Hip Joint Kinematic Covariation During Gait Before and 1-Year After Hip Arthroscopic Surgery for Femoroacetabular Impingement Syndrome

“…The current study adds to previous studies on gait biomechanics before and after surgery for FAIS (7)(8)(9)(10)(11), as well as another study that investigated muscular synergy control of gait in patients with hip pathology (38). Rylander et al reported that patients demonstrated improvement of maximal hip internal rotation and sagittal plane range motion during gait following hip arthroscopic surgery for FAIS (7).…”

“…We acknowledge that the sample size of the study is small, however, the longitudinal design evaluating patients at 1-year after hip arthroscopy is valuable because extremely limited data exists in this area (7)(8)(9). Challenges associated with patient attrition, the time burden of marker based motion analysis testing, and limitation in number of high volume hip arthroscopy centers capable of motion analysis testing contributes to the generally small sample sizes and limited number of postoperative biomechanical studies in FAIS and (7)(8)(9)(10)(11). Other studies have attempted to overcome this by including patients undergoing any type of surgery for FAIS (open vs. arthroscopic), ( 9) and have reported on short term outcomes (10,11).…”

“…All previous studies examining gait kinematics in people with FAIS and before and after surgery have used a traditional analysis approach by statistically comparing discrete biomechanical variables (i.e., maximum or minimum values) in each plane of motion (7)(8)(9)(10)(11). A draw back to this analysis approach is that it eliminates the majority of biomechanical data collected during the task.…”

“…A recent systematic review found that across studies, the main hip joint kinematic differences between people with FAIS and healthy controls are lower peak hip extension angles, less total sagittal plane hip joint range of motion and less peak internal rotation during the stance phase of walking (6). Although these studies establish that movement patterns during walking are different between people with FAIS and healthy controls, evidence on hip biomechanics before and after arthroscopic surgery for FAIS remains limited (6)(7)(8)(9)(10)(11). Rylander and colleagues reported that following arthroscopic hip surgery for FAIS patients demonstrated improved sagittal plane and internal hip joint range of motion during walking (7,8).…”

“…Rylander and colleagues reported that following arthroscopic hip surgery for FAIS patients demonstrated improved sagittal plane and internal hip joint range of motion during walking (7,8). However, more recent studies examining gait kinematics before and after hip arthroscopic surgery have reported no differences in hip kinematics after this surgical procedure (10,11). Significantly reducing hip joint kinematic data using traditional analyses may be the potential reason for the inconsistency among these biomechanical studies before and after surgery for FAIS.…”