PurposeTo investigate clinical outcomes and return to sports-related activity following endoscopic shelf acetabuloplasty combined with labral repair in the treatment of the active patients with developmental dysplasia of the hip (DDH).MethodsBetween 2011 and 2013, 32 patients (36 hips; 11 males and 21 females; 11 right 17 left 4 bilateral; median age 28.5, range 12–51 years), who underwent endoscopic shelf acetabuloplasty combined with labral repair and met the inclusion criteria were enrolled in this study. There was a minimum follow-up of 2 years (average 32.3 ± 3 months, range 24–48 months). Patient-reported outcome (PRO) scores including the modified Harris Hip Score (MHHS) and Non-Arthritis Hip Score (NAHS) were obtained preoperatively and at final follow-up for the assessment of surgical outcomes.ResultsThe mean MHHS significantly improved from 68.4 ± 14.3 (range 23.1–95.7) preoperatively to 94.5 ± 8.5 (range 66–100) at final follow-up (p = 0.001). Similarly, the NAHS also significantly improved from 51.3 ± 11.9 (range 23–76) preoperatively to 73.0 ± 7.4 (range 44–80) at final follow-up (p = 0.001). The mean LCE angle significantly increased postoperatively but partially decreased at final follow-up (mean preoperative versus postoperative versus final follow-up: 16.0 range 5–24, versus 40.1 range 27–58, versus 30.1 range 20–41. p = 0.001, respectively). There were 3 patients who returned to a higher activity level, 20 patients who returned to the same activity level, and 6 patients who returned to a lower activity level. The mean period from surgery to return to play was 9.0 ± 3.5 months (range 5–18).ConclusionEndoscopic shelf acetabuloplasty provides promising clinical outcomes and return to sports-related activity for active patients with DDH.Level of evidenceLevel IV.