Preoperative Malnutrition and Risk of Periprosthetic Joint Infection After Reverse Total Shoulder Arthroplasty: Evaluation Using the Geriatric Nutritional Risk Index.

BACKGROUND: Poor nutritional status has been reported to adversely affect postoperative outcomes in orthopedic surgery; however, its role in reverse total shoulder arthroplasty (rTSA) has not been fully established. This study investigated whether pre-operative nutritional status, evaluated using the Geriatric Nutritional Risk Index (GNRI), was associated with postoperative complications and clinical outcomes after rTSA.

METHODS: A retrospective analysis was conducted on 157 patients who underwent rTSA at the institution between 2014 and 2023, with a minimum follow-up of 2 years. Patients were stratified into two groups according to GNRI values: ≥98 (normal nutrition) and <98 (malnutrition). The primary outcome was postoperative complications. Secondary outcomes included range of motion, visual analog scale pain scores, American Shoulder and Elbow Surgeons scores, Constant Score, and achievement of the minimal clinically important difference at 2 years. Continuous and categorical variables were compared using the Student's t-, chi-square, or Fisher's exact tests; multivariate logistic regression analysis was conducted to determine independent predictors of periprosthetic joint infection.

RESULTS: Of the 157 patients, 109 (69.4%) were classified as nutritionally normal and 48 (30.6%) as malnourished. The malnutrition group was substantially older and demonstrated lower body mass index, serum albumin, and hemoglobin levels. Although the overall complication rates were comparable between groups, periprosthetic joint infection occurred more frequently in the malnutrition group (10.4% vs. 1.8%; P = 0.03). Multivariate analysis indicated that malnutrition was an independent risk factor for periprosthetic joint infection (odds ratio, 6.88; 95% confidence interval, 1.30-36.3; P = 0.02). No differences were observed between groups in range of motion, visual analog scale pain scores, American Shoulder and Elbow Surgeons scores, Constant Score, or achievement of the minimal clinically important difference at 2 years; however, forward flexion was significantly reduced in the malnutrition group.

CONCLUSIONS: Preoperative malnutrition, as defined by a Geriatric Nutritional Risk Index <98, was associated with an increased risk of periprosthetic joint infection following rTSA. Short-term clinical outcomes were similar regardless of nutritional status. These findings suggest that preoperative nutritional screening and intervention may be important for reducing periprosthetic joint infection in patients undergoing rTSA.