ISAKOS: 2023 Congress in Boston, MA USA

2023 ISAKOS Biennial Congress ePoster

 

A 135° Short Inlay Humeral Stem Leads to Comparable Radiographic and Clinical Outcomes Compared to a Standard-Length Stem for Reverse Shoulder Arthroplasty

Brandon Erickson, MD, New York, NY UNITED STATES
Patrick J. Denard, MD, Medford, OR UNITED STATES
Justin W. Griffin, MD, Charlottesville, VA UNITED STATES
Thomas Wittman, MD, Munich GERMANY
Patric Raiss, MD, Heidelberg GERMANY
Evan Lederman, MD, Phoenix, AZ UNITED STATES
Brian C Werner, MD, Charlottesville, VA UNITED STATES

Rothman, New York, NY, UNITED STATES

FDA Status Not Applicable

Summary

A short inlay stem leads to comparable radiographic findings and revision-free survival compared to a standard-length stem when placed with a press-fit technique for RTSA.

ePosters will be available shortly before Congress

Abstract

Background

Humeral stem length in reverse total shoulder arthroplasty (RTSA) has decreased in recent years in an attempt to preserve more bone and facilitate stem removal in the revision setting. The purpose of this study was to compare the clinical and radiographic outcomes of a short to standard length stem RTSA. The authors hypothesized that there would be no difference in radiographic or clinical outcomes at short-term follow-up.

Methods

Patients who underwent RTSA using a press-fit standard or short length humeral component with a consistent geometry (Univers Revers™, or Revers™ Apex; Arthrex, Inc., Naples, FL, USA) were evaluated in a multicenter retrospective review. Minimum clinical follow up was 2 years. Immediate postoperative radiographs were used to assess initial alignment and filling ratios. Additionally, radiographs at 2 years were evaluated for signs of stress shielding and/or loosening. Clinical outcome scores and range of motion (ROM) were evaluated at final follow up and compared between groups.

Results

220 patients with short stem RTSA and 357 patients with standard length stem RTSA were analyzed. There was no difference in baseline function between short and standard-length stem patients. Patients in the short stem group had higher postoperative American Shoulder and Elbow Surgeon (ASES) (84.6 vs. 80.8 p=0.014) and Western Ontario Osteoarthritis of the Shoulder (WOOS) (86.5 vs. 82.7, p=0.025). Patients in the short stem group also had greater postoperative active forward flexion (139° vs. 132° p=0.003) and internal rotation with the arm at 90° of abduction (43° vs. 32° p<0.001) than patients in the standard-length group. Radiographically, there was a higher metaphyseal (p=0.049) and diaphyseal (p<0.001) fill ratio in the short stem group while there was no difference in postoperative alignment, radiographic signs of loosening, or revision for loosening between groups (all p>0.05).

Conclusion

A short inlay stem leads to comparable radiographic findings and revision-free survival compared to a standard-length stem when placed with a press-fit technique for RTSA. Clinical outcomes are also equivalent or slightly improved with a short stem compared to a standard-length stem.