Sitting Pain Is More Common Than Standing Hip Pain Regardless of Diagnosis of Femoroacetabular Impingement Syndrome Versus Hip Dysplasia: A Prospective Comparative Study.

Purpose: To explore a possible correlation between sitting versus standing hip pain and a primary diagnosis of femoroacetabular impingement syndrome (FAIS) versus hip dysplasia. Methods: All new patients presenting to a hip preservation clinic starting in September 2023 were prospectively asked, "Do you have more hip pain with sitting or standing for a long time?" Patients were divided into two groups based on primary diagnosis: FAIS or hip dysplasia. Primary diagnosis was based on a combination of history, physical examination, and imaging. Patients with concomitant FAIS and dysplasia were given a primary diagnosis of dysplasia if they were recommended to undergo a periacetabular osteotomy (PAO), although patients with concomitant dysplasia and a large cam lesion were excluded. Logistic regression analysis was performed to determine if any variables were significantly associated with sitting versus standing hip pain. Results: A total of 115 patients (118 hips) were included (30 male, 88 female). FAIS and hip dysplasia were the diagnoses in 71 and 47 hips, respectively. Mean age at initial presentation was 34 years. Overall, regardless of diagnosis, sitting pain (n = 74; 62.7%, 95% CI 53.7-70.9) was found to be more likely than standing hip pain (n = 44; 37.3%, 95% CI 29.1-46.3). There was no evidence of a difference in the odds of experiencing sitting versus standing hip pain between the FAIS and hip dysplasia groups ( Conclusions: Sitting pain is more common than standing pain regardless of diagnosis of FAIS versus hip dysplasia, with no evidence of an association between FAI/sitting pain and dysplasia/standing pain. Level of Evidence: Level II, consecutive series diagnostic study.