ABSTRACT
Purpose@#This study examined the patient-reported outcome scores at mid-term follow-up after arthroscopic labral preservation in patients with borderline hip dysplasia. @*Materials and Methods@#Data were collected retrospectively from patients who underwent arthroscopic labral preservation. Among the 61 patients classified with hip dysplasia, patients with arthritis beyond Tönnis grade II were excluded, Patients with subchondral bony exposure were excluded even if they had arthritis of Tönnis grade I. Forty-two patients with borderline hip dysplasia were enrolled among patients whose lateral center edge angle (LCEA) was between 18° and 25°. The PRO scores including the modified Harris hip score (mHHS), hip outcome score activities of daily living (HOS-ADL), hip outcome score sport-specific subscale (HOS-SSS) and visual analog scale (VAS), were collected and compared preoperatively, and then at one year and a minimum of five years after surgery. @*Results@#The mean preoperative LCEA and Tönnis angle were 20.9° (range, 18° to 25°) and 6.3° (range, 0° to 18°), respectively. The mean follow-up was 64.8 (range, 60 to 84) months. The mean mHHS increased from 73.5 before surgery to 86.2 in the fifth year after surgery (p<0.01), the mean HOS-ADL from 70.5% before surgery to 84.9% in the fifth year after surgery (p<0.01), and the mean HOS-SSS from 51.4 before surgery to 69.4 in the fifth year after surgery (p<0.01). The mean VAS score improved from 6.3 before surgery to 1.5 in the fifth year after surgery (p<0.01). @*Conclusion@#Arthroscopic labral preservation performed in appropriately selected patients with borderline dysplasia showed good results at mid-term follow-up. In borderline hip dysplasia without the progress of osteoarthritis and subchondral bone exposure, arthroscopic labral preservation may be considered a good and less invasive option.