Intraoperative Intra-articular Antibiotic Injection Reduces Infection in Shoulder Arthroplasty.

Deep infection is a debilitating complication after shoulder arthroplasty. The authors hypothesized that an intra-articular, intraoperative injection of antibiotics would result in a lower infection rate compared with intravenous antibiotics alone. Before 2007, 164 patients (group A) did not receive intra-articular antibiotics. From 2007 to 2018, 1324 patients (group B) received intra-articular antibiotics. Patients received intra-articular gentamicin at the end of surgery with the addition of 1 g of cefazolin in January 2014. Records were retrospectively reviewed for comorbidities, type of surgery, and infection. The cohort that received intra-articular antibiotics was compared with the cohort that did not to determine the effect of prophylactic intra-articular antibiotic administration in preventing infection. There was 1 deep infection in the antibiotic group compared with 5 in the non-antibiotic group ( P <.001). Superficial infections developed in 2 cases of patients treated with antibiotics; there were no superficial infections in patients treated without antibiotics ( P =.62). One previous study evaluated intra-articular injection of antibiotics for shoulder arthroplasty and found significantly lower rates of infection with the injection of intra-articular gentamicin. In this retrospective follow-up study, the injection of intra-articular gentamicin or gentamicin and cefazolin effectively decreased rates of postoperative infection. At mean follow-up of 399 days, intra-articular antibiotics at the time of surgery resulted in significantly fewer deep infections. Given the minimal risk of adverse events and minimal cost, this is a valid method of reducing infections in total shoulder arthroplasty. [ Orthopedics . 202x;4x(x):xx-xx.].