Background: Periprosthetic joint infections (PJI) are among the most morbid complications in total hip arthroplasty (THA). The ideal incubation time, however, for intraoperative cultures for PJI diagnosis remains unclear. As such, the aim of this study was to determine if any differences existed in culture-positive rates and organism detection between five-day and fourteen-day cultures. Methods: This retrospective cohort study consisted of THA cases diagnosed with PJI performed between May 2014 and May 2020 at a single tertiary-care institution. Analyses compared five-day and fourteen-day cultures and carried out a pre-specified subgroup analysis by organism and PJI type. Results: A total of 147 surgeries were performed in 101 patients (57.1% females), of which 65% (n = 98) obtained five-day cultures and 34% (n = 49) obtained fourteen-day cultures. The positive culture rate was 67.3% (n = 99) with Staphylococcus aureus being the most common pathogen identified (n = 41 specimens, 41.4%). The positive culture rate was not significantly different between groups (66.3% five-day, 69.4% fourteen-day, p = 0.852). Fourteen-day cultures had a significantly longer time-to-positive culture (5.0 days) than five-day cultures (3.0 days, p < 0.001), a higher rate of fungi (5.6% vs. 0%), and a lower rate of Gram-negatives (4.5% vs. 18.7%, p = 0.016). Conclusions: Fourteen-day cultures did not increase the positivity rate, had higher rates of slow-growth pathogens, and had a longer time-to-positivization than five-day cultures. Prolonged culture holds may provide more thorough organism detection for PJI without increasing the diagnostic culture yield.

Background: Multimodal analgesia in total hip arthroplasty (THA) provides better pain control, mobility, and reduced side effects compared to monotherapies. Local infiltration analgesia (LIA) and regional nerve blocks (RNBs) are commonly used throughout these protocols. This study aimed to compare these procedures as part of a multimodal analgesia protocol for patients undergoing THA. Materials and Methods: A retrospective review of 1100 consecutive elective primary THAs was performed in 996 patients between June 2018 and December 2021. The RNB consisted of a preoperative continuous femoral nerve catheter and single-shot obturator nerve block, and LIA consisted of the intraoperative infiltration of weight-based bupivacaine. Results: A total of 579 (52.6%) patients received RNB, and 521 (47.4%) received LIA. Mean oral morphine equivalents (OMEs) during the first four hours postoperatively were significantly lower for LIA group (p < 0.001). However, the numeric pain rating scale in the post-anesthesia care unit (PACU) was similar between groups. Patients with LIA had significantly greater first ambulation distance in the PACU (p < 0.001), higher successful same-day discharge rate (p = 0.029), fewer falls (p = 0.041), and less refill OMEs post-discharge (p < 0.001) than RNB. Conclusions: In the setting of similar pain management between groups and better functional outcomes for LIA, the use of minimally invasive procedures like LIA for pain control following THA is favorable.