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Updated: Sep 21, 2026
Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
Lower Geriatric Nutritional Risk Index is associated with increased risk of acromial stress fracture following
Leonard Stokes1, Vidhur Polam1, Yousy Martinez Sauvanell2
1Oregon Shoulder Institute, Medford, OR, USA.
Background:
Acromial and scapular spine stress fractures are serious complications following reverse total shoulder arthroplasty (rTSA), and patient-level risk factors may contribute to their development. The Geriatric Nutritional Risk Index (GNRI) is a validated marker of physiologic reserve. The purpose of this study was to evaluate the association between GNRI and post-operative stress fracture after rTSA. We hypothesized that lower GNRI would be associated with increased fracture risk.
Methods:
We performed a retrospective 1:2 age- and sex-matched case-control study of patients undergoing primary rTSA. Forty-five patients who developed post-operative acromial or scapular spine stress fracture were matched to 90 controls without fracture. Demographic variables collected included age, sex, body mass index, diagnosis, and comorbidities. GNRI was calculated pre-operatively and post-operatively and analyzed as a continuous variable and using predefined thresholds (<98, <103, <109). Conditional logistic regression adjusted for diagnosis and comorbidities. Receiver-operating characteristic analysis assessed discriminatory ability.
Results:
A total of 135 patients were included (mean age, 72.8 years; 53% female). Patients with stress fracture had lower pre-operative GNRI (107.4 ± 12.4 vs. 114.0 ± 13.9; P = .007) and post-operative GNRI (105.5 ± 14.9 vs. 114.8 ± 14.5; P = .001). Post-operative GNRI <109 was more common among fracture patients (60% vs. 30%; P = .001). In matched multivariable analysis, each 1-point increase in post-operative GNRI was associated with a 5% reduction in fracture odds (odds ratioOR, 0.95; 95% confidence interval [CI], 0.92-0.99; P = .015). Post-operative GNRI <109 was independently associated with fracture (odds ratio, 3.64; 95% CI, 1.02-13.02; P = .047). Receiver-operating characteristic analysis demonstrated moderate discrimination (area under the curve, 0.70; 95% CI, 0.60-0.79).
Conclusion:
In this matched case-control analysis, lower post-operative GNRI was independently associated with increased risk of acromial and scapular spine stress fracture following rTSA. GNRI may serve as a practical perioperative risk stratification tool in patients undergoing reverse shoulder arthroplasty.