Bariatric surgery prior to total hip arthroplasty: does timing or type matter?

Morbid obesity is a known risk-factor for increased complications following total hip arthroplasty (THA). Thus, many orthopaedic surgeons recommend bariatric surgery (BS). However, there is no consensus on the type (commonly either a Roux-en-Y gastric bypass [RYGB] or sleeve gastrectomy [SG]) and timing of BS prior to THA. Therefore, the purpose of this study is to compare BS recipients prior to THA to assess differences in 90-day to 2-year medical/surgical complications as well as revisions for: (1) type of BS (RYGB and SG); and (2) timing of BS. Additionally, we aim to assess risk factors for postoperative prosthetic joint infections (PJIs), dislocations, and revisions.

We queried a national, all-payer database to identify patients undergoing primary THA from January 2010 to October 2020 (n = 715,100). Patients were then divided into 6 cohorts: 2 cohorts without history of BS (body mass index [BMI] kg/m² 20-35 [n = 59,995]) and BMI > 40 [n = 36,799]); 2 cohorts with previous RYGB (n = 1278) or SG (n = 1051); and 2 cohorts that underwent BS either 6-12 months (n = 412) and >12 months (n = 1655) prior to the THA. Bivariate chi-square analyses of medical and surgical outcomes at 90 days-2 years were conducted. Multivariate logistic regressions identified independent risk factors for PJIs, dislocations, and revisions.

At 90 days-2 years, no differences in postoperative medical/surgical complications or revisions were seen among timing or type of BS. The BMI > 40 kg/m² cohort had the highest complication profile among all other cohorts. Timing and type of BS has similar odds of PJIs, dislocations, and revisions.

Patients undergoing RYGB or SG 6-12 months and >1 year prior to THA showed similar complications profiles. These results suggest, bariatric patients do not need to wait 1 year before undergoing a THA.