Abstract
It is estimated that approximately 3.1 – 7.7% of the general population suffers from primary osteoarthritis of the hip, with up to 42% of these cases being bilateral. The odds of undergoing a contralateral THA after index unilateral THA range from 16–85%. Up to 20% of these patients have the contralateral THA within 5 years. For this patient population, simultaneous bilateral THA may be an appealing option but it remains controversial. Proponents of bilateral simultaneous THA cite advantages such as a single anesthetic exposure, overall shorter length of hospital stay, quicker recovery, earlier return to function, less time off of work, and potential economic advantages. Only recently has there been more data emerging on patients undergoing simultaneous bilateral THA through the direct anterior approach (DAA). The DAA has the distinct advantage of supine positioning that facilitates easy exposure to both hips without the need to reposition the patient onto a fresh surgical incision while performing the second operation. Recent publications suggest that bilateral simultaneous DAA is a safe procedure and may have economic benefits as well.
At our institution between 2010 and 2016, a consecutive series of 105 patients (210 hips) undergoing simultaneous bilateral DAA THA and a matched group of 217 patients undergoing unilateral DAA THA by the same surgeon at a single institution were reviewed. The two groups were matched by gender, age, body mass index and date of surgery. There were no significant differences between the two groups in terms of early complications. There were 2 complications in the unilateral group that were intraoperative nondisplaced calcar fractures that were treated with a single cerclage cable and 50% weight bearing for four weeks. There were 6 in-hospital systemic complications in the unilateral group compared to 7 in the bilateral group (p = 0.129). In-hospital systemic complications were similar between the two groups and included urinary retention, cardiopulmonary abnormalities, alcohol withdrawal, and nausea / vomiting.
There were a total of 14 30-day follow-up hip-related complications in the unilateral group compared to 5 in the bilateral group (p = 0.06) These complications were similar between the two groups and included wound healing issues, tendinitis / bursitis, deep infection, nerve palsy, stem subsidence, and instability. Intraoperative estimated blood loss (EBL) was 360cc in the unilateral group compared to 555cc in the bilateral group (p < 0.001). The bilateral group had lower postoperative day one (POD1) hemoglobin (9.5 g/dl vs. 10.2 g/dl; p < 0.001). Four percent of unilateral patients required blood transfusion compared to 11% in the bilateral group. There were significant differences between the two groups in terms of distance ambulated on POD1 and length of stay (LOS). On average, the unilateral patients walked 235 feet on POD1 compared to 182 feet for the bilateral patients (p < 0.001). Length of stay was significantly longer in the bilateral group (1.95 days vs. 1.12 days; p < 0.001). All 322 patients involved in the study were discharged to home except for a single patient in the bilateral group who was discharged to a skilled nursing facility.
In conclusion, we found no difference in in-hospital or 30-day complication rates when comparing the simultaneous bilateral group to the unilateral group. The main difference when compared to unilateral surgery is increased blood loss yet this did not directly result in specific complications. Simultaneous bilateral DAA THA can be performed safely and without an unacceptably high perioperative complication rate.
