The association of elevated body mass index (BMI) with complications and outcomes following anatomic total shoulder arthroplasty: a systematic review

Purpose: Obesity has been associated with increased perioperative complications following shoulder arthroplasty, though this finding has not been consistently reported. The purpose of this systematic review is to summarize the correlation between elevated body mass index (BMI) and the prevalence of perioperative complications and clinical outcomes following anatomic total shoulder arthroplasty (aTSA). Methods: An extensive literature search of PubMed, Embase, ScienceDirect, and Google Scholar was conducted up until October 2020. Clinical studies that specifically examined the association between BMI and/or various categories of obesity with perioperative complications and functional outcomes following aTSA were included. Public databases (NIS, ACS-NSQIP, PearlDiver, and statewide databases) were largely excluded from the analysis unless procedural codes allowed for differentiation between reverse total shoulder arthroplasty (rTSA) and aTSA. Results: Eleven studies were included in this systematic review - 9 studies reported solely on perioperative complications, 1 study solely on functional outcomes, and 1 study on both complications and outcomes following aTSA. Seven papers had a MINORS (Methodological Index for Non-Randomized Studies) score of <16, indicating low methodological quality. There was no association found between elevated BMI and overall perioperative medical and surgical complications, surgical site infection (SSI), re-operation without revision, aseptic revision, periprosthetic fracture, intraoperative blood loss, need for blood transfusion, 90-day re-admission, absolute hospital LOS or short-term mortality. There is an increased risk for overall revision following aTSA and need for extended hospital LOS in patients with elevated BMI. Range of motion of the operative shoulder, pain, and patient reported outcome measures (PROMs) have generally demonstrated significant improvement following unconstrained arthroplasty. Discussion: Increasing BMI was not found to be associated with an elevated risk for the majority of perioperative complications following aTSA. Range of motion and patient reported functional outcomes can be expected to improve, even amongst morbidly obese patients.