Related Experiment Video
Updated: Nov 26, 2025
Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
Intraoperative measurements of reverse total shoulder arthroplasty contact forces
Kevin W Farmer1, Masaru Higa2, Scott A Banks3
1Department of Orthopaedics and Rehabilitation, University of Florida, 3450 Hull Road, 3rd Floor, Gainesville, FL, 32608, USA. farmekw@ortho.ufl.edu.
Purpose:
Instability and fractures may result from tensioning errors during reverse total shoulder arthroplasty (RTSA). To help understand tension, we measured intraoperative glenohumeral contact forces (GHCF) during RTSA.
Methods:
Twenty-six patients underwent RTSA, and a strain gauge was attached to a baseplate, along with a trial glenosphere. GHCF were measured in passive neutral, flexion, abduction, scaption, and external rotation (ER). Five patients were excluded due to wire issues. The average age was 70 (range, 54-84), the average height was 169.5 cm (range, 154.9-182.9), and the average weight was 82.7 kg (range, 45.4-129.3). There were 11 females and 10 males, and thirteen 42 mm and 8 38 mm glenospheres.
Results:
The mean GHCF values were 135 N at neutral, 123 N at ER, 165 N in flexion, 110 N in scaption, and 205 N in abduction. The mean force at terminal abduction is significantly greater than at terminal ER and scaption (p < 0.05).
Conclusions:
These findings could help reduce inappropriate tensioning.
