FEMOROACETABULAR IMPINGEMENT: PREVALENCE OF RADIOGRAPHIC MORPHOLOGY IN INDIAN POPULATION, ETIOLOGY AND CLINICAL MANAGEMENT.

Background: Femoroacetabular impingement (FAI) is an often-unnoticed cause of hip and groin pain in adolescents and adults. If untreated, it is a precursor of early primary hip osteoarthritis. The prevalence of FAI in Indian population is under-documented. Current study aims to determine the prevalence of radiographic morphology of FAI in random individuals undergoing pelvic radiography at the tertiary healthcare referral hospital and analyze the associated groin pain, etiological factors and clinical management.

Methods: This observational cross-sectional study included 550 patients, 18 to 50 years of age. Pelvic radiographs were prospectively analyzed for FAI signs. Groin pain was assessed with Non-Arthritic Hip Score (NAHS). Hips were classified based on the number of present radiological abnormalities and symptomatic groin pain. Patients with clinical symptoms were investigated by computed tomography (CT) scans and conservatively managed. Multivariate logistic regression analysis was used for etiological risk factor analysis.

Results: Radiographic morphology of FAI was prevalent in total 453 individuals (82%) and 803 hips (73%). Out of these, 350 individuals (77%) had bilateral and 103 (23%) had unilateral findings. Mean age of study population with mixed urban rural ethnicity was 32.3+17.8 years. Male to female ratio was 2:1. Lateral center-edge angle was the most common finding (32.6%), and crossover sign was the least (6%). Pincer morphology was predominant finding (36.2%), followed by mixed (22.8%) and cam (13.5%). Among these, only 110 hips (10%) clinically experienced pain (with mean NAHS score of 87.4) of which 69 hips presented multiple radiological morphologies of FAI that significantly corelated with CT scan findings. Significant associations of result (p-value <0.05) were revealed with demographic parameters, baseline characteristics and multiple etiological factors.

Conclusion: Radiographic morphology of FAI is prevalent in 82% of studied Indian population and 73% of total hips. These findings were accurately validated on CT scans in symptomatic 10% patients. Causal etiological association found out can successfully guide future self-preventive measures required to prevent development of this musculoskeletal disease in young adults. Long-term conservative management shows encouraging results with possible pain free survival.