EP265 The Impact of Sagittal Spinopelvic Parameters And Kinematics on the Morphology and Symptomatology of Femoroacetabular Impingement: A Systematic Review and Meta-Analysis

Femoroacetabular impingement (FAI) morphology is frequently observed in asymptomatic populations, with up to 30% demonstrating radiographic evidence of cam or mixed-type deformities. Spinopelvic balance influences the orientation of the pelvis and acetabulum, potentially altering hip mechanics and modulating FAI presentation. However, the precise impact of spinopelvic parameters on FAI remains unclear.

To enhance understanding of the pathogenesis of FAI and to inform potential prevention and therapeutic targets, this study aimed to clarify the relationship between spinopelvic balance, FAI morphology, and symptomatology.

A comprehensive search of PubMed, EMBASE, and Scopus was performed from inception to December 23, 2024, in accordance with PRISMA guidelines. Studies reporting spinopelvic parameters in symptomatic or asymptomatic FAI (with comparisons among FAI subgroups or with controls) were included. Two reviewers independently screened articles, extracted data, and assessed methodological quality using the Newcastle–Ottawa Scale (NOS), with disagreements resolved by a third reviewer. Pairwise meta-analyses of mean differences were stratified by FAI type, symptomatology/morphology, and spinopelvic parameters.

Of 1824 articles screened, 41 studies (3750 participants: 1343 symptomatic FAI, 821 asymptomatic FAI, 1586 controls) met inclusion criteria. The median NOS score was 6 (range, 2–8). A greater pelvic incidence (PI) was associated with cam morphology becoming symptomatic (mean difference [MD] = 4.94° [95%CI –0.1, 9.98]; p=0.05), whereas a smaller PI correlated with the presence of pincer morphology (MD = –4.49° [–6.21, –2.76]; p<0.01), as well as an corresponding trend observed between lower PI and cam morphology (MD = 1.75° [−0.70, 4.19], p>0.05). No statistically significant findings emerged regarding postural parameters. Kinematic findings showed reduced second-half posterior pelvic excursion in symptomatic and morphological cam FAI during deep flexion squatting (MD = –5.23° [–7.17, –3.30]; p<0.01), and increased global pelvic excursion during gait (MD = 0.38° [0.05, 0.72]; p=0.03).

Reduced pelvic rollback and a tendency toward greater anterior tilt were associated with symptomatic FAI, indicating potential targets for conservative management. Lower pelvic incidence was linked to FAI morphologies, suggesting preventive strategies during skeletal development. These findings underscore the importance of dynamic spinopelvic parameters in shaping future research and refining clinical counseling.