Direct anterior total hip arthroplasty after hip arthroscopy: A retrospective review

Introduction: Limited studies have investigated outcomes of total hip arthroplasty (THA) after ipsilateral hip arthroscopy, with mixed conclusions. There is need to provide clarity on potential risks/complications associated with this sequence of operations. Methods: This is a retrospective single surgeon cohort study, evaluating patients from 01/01/2012-01/01/2020 undergoing direct anterior THA for osteoarthritis, with minimum 90-day follow-up. There were two groups: previous hip arthroscopy plus THA (THA+) and isolated THA (control) without previous hip arthroscopy. All THA + patients had undergone one previous hip arthroscopy prior to THA. Quantitative variables were evaluated using the Mann-Whitney-U test or a two-tailed unpaired t-test. Nominal variables were evaluated using the chisquare or Fisher's Exact test. Significance was assessed at p < 0.05. Results: Seventy-one patients were included, 38 patients in the THA + group, and 33 patients in the control group. Surgery duration was longer in the THA + group (74 min THA + [SD = 9.5], 60 min control [SD = 11.3], p < 0.0001). The only secondary outcome with significance was average estimated blood loss (400 mL THA+, 275 mL control, p = 0.009). Only one THA + patient required postoperative transfusion (p = 1.0). There were no postoperative deep infections requiring debridement, intra-operative fractures requiring fixation, or postoperative dislocations in either group. The THA group had one post-operative fracture requiring surgery. The THA + group was younger (average) than the control group (52 THA + [SD = 9.9], 58.4 control [SD = 8.8], p = 0.0062). Conclusion: This study highlights increased operative time and estimated blood loss after previous ipsilateral hip arthroscopy. Surgeons should recognize implications on time management, and assist surgeons when deciding to perform a THA at a surgery center vs hospital. These results contribute to a growing body of literature indicating no increase in major complication rate of THA after ipsilateral hip arthroscopy.