Among adults undergoing hip fracture surgery, increased wait time was associated with a greater risk of 30-day mortality and other complications. A wait time of 24 hours may represent a threshold defining higher risk.

IMPORTANCE Overlapping surgery, also known as double-booking, refers to a controversial practice in which a single attending surgeon supervises 2 or more operations, in different operating rooms, at the same time. OBJECTIVE To determine if overlapping surgery is associated with greater risk for complications following surgical treatment for hip fracture and arthritis. DESIGN, SETTING, AND PARTICIPANTS This was a retrospective population-based cohort study in Ontario, Canada (population, 13.6 million), for the years 2009 to 2014. There was 1 year of follow-up. This study encompassed 2 large cohorts. The "hip fracture" cohort captured all persons older than 60 years who underwent surgery for a hip fracture during the study period. The "total hip arthroplasty" (THA) cohort captured all primary elective THA recipients for arthritis during the study period. We matched overlapping and nonoverlapping hip fractures by patient age, patient sex, surgical procedure (for the hip fracture cohort), primary surgeon, and hospital. EXPOSURES Procedures were identified as overlapping if they overlapped with another surgical procedure performed by the same primary attending surgeon by more than 30 minutes. MAIN OUTCOMES AND MEASURES Complication (infection, revision, dislocation) within 1 year. RESULTS There were 38 008 hip fractures, and of those, 960 (2.5%) were overlapping (mean age of patients, 66 years [interquartile range, 57-74 years]; 503 [52.4%] were female). There were 52 869 THAs and of those, 1560 (3.0%) overlapping (mean age, 84 years [interquartile range, 77-89 years]; 1293 [82.9%] were female). After matching, overlapping hip fracture procedures had a greater risk for a complication (hazard ratio [HR], 1.85; 95% CI, 1.27-2.71; P = .001), as did overlapping THA procedures (HR, 1.79; 95% CI, 1.02-3.14; P = .04). Among overlapping hip fracture operations, increasing duration of operative overlap was associated with increasing risk for complications (adjusted odds ratio, 1.07 per 10-minute increase in overlap; P = .009). CONCLUSIONS AND RELEVANCE Overlapping surgery was relatively rare but was associated with an increased risk for surgical complications. Furthermore, increasing duration of operative overlap was associated with an increasing risk for complications. These findings support the notion that overlapping provision of surgery should be part of the informed consent process.

IMPORTANCE Controversy exists about the preferred surgical approach for total hip arthroplasty (THA).OBJECTIVE To determine whether an anterior approach is associated with lower risk of complications than either a lateral or posterior approach. DESIGN, SETTING, AND PARTICIPANTS Population-based retrospective cohort study of all adults in Ontario, Canada, who had undergone primary THA for osteoarthritis between April 1, 2015, and March 31, 2018. All patients were followed up over a 1-year period (study end date, March 31, 2019). EXPOSURES Surgical approach (anterior vs lateral/posterior) for THA. MAIN OUTCOMES AND MEASURES Major surgical complications within 1 year (composite of deep infection requiring surgery, dislocation requiring closed or open reduction, or revision surgery). Outcomes were compared among propensity-score matched groups using Cox proportional hazards regression. RESULTS Of the 30 098 patients (mean [SD] age, 67 years [10.7 years]; 16 079 women [53.4%]) who underwent THA, 2995 ( 10%) underwent the anterior approach; 21 248 (70%), the lateral approach; and 5855 (20%) the posterior approach performed at 1 of 73 hospitals by 1 of 298 surgeons. All patients were followed up for 1 year. Compared with those undergoing the lateral or posterior approach, patients undergoing an anterior approach were younger (mean age, 65 vs 67 years; standardized difference, 0.17); had lower rates of morbid obesity (4.8% vs 7.6%; standardized difference, 0.12), diabetes (14.2% vs 19.9%; standardized difference, 0.15), and hypertension (53.4% vs 62.9%; standardized difference, 0.19); and were treated by higher-volume surgeons (median range, 111 procedures; interquartile range, 69-172 vs 77 procedures, interquartile range, 50-119 in the prior year; standardized difference, 0.55). Compared with 2993 propensity-score matched patients undergoing a lateral or posterior approach, the 2993 matched patients undergoing anterior approaches had a significantly greater risk of a major surgical complication (61 patients [2%] vs 29 patients [1%]; absolute risk difference, 1.07%; 95% CI, 0.46%-1.69%; hazard ratio, 2.07; 95% CI, 1.48 to 2.88).CONCLUSIONS AND RELEVANCE Among patients undergoing total hip arthroplasty, an anterior surgical approach compared with a posterior or lateral surgical approach was associated with a small but statistically significant increased risk of major surgical complications. The findings may help inform decisions about surgical approach for hip arthroplasty, although further research is needed to understand pain and functional outcomes.