Stemmed versus stemless humeral implants in anatomic total shoulder arthroplasty: a systematic review and...

A recent advancement in anatomic total shoulder arthroplasty (aTSA) has been the development of stemless humeral implants The objective of this systematic review and meta-analysis is to compare outcomes of traditional stemmed humeral implants (S+) and stemless humeral implants (S-) in aTSA.

A search was conducted across 7 databases. Titles and abstracts were screened for eligibility. Full texts were screened for inclusion. Demographic and study results were extracted from articles that met the inclusion criteria. Meta-analysis was conducted to evaluate outcomes.

Twenty-one studies were included, of which 19 met the inclusion criteria for meta-analysis. No studies were poor quality or at high risk of bias according to the quality assessment. A meta-analysis showed no significant difference in post-operative Constant scores (Cohen d = -0.27; 95% confidence interval [CI]: -0.79 to 0.25; P = .3), forward flexion(Cohen d = -0.07; 95% CI: -0.32 to 0.17; P = .56), abduction (Cohen d = -0.07; 95% CI: -0.46 to 0.33; P = .73), external rotation (Cohen d = -0.12; 95% CI: -0.39 to 0.15; P = .39), restoration of the center of rotation (Cohen d = 0.01; 95% CI: -0.58 to 0.60; P = .97), or revision risk (odds ratio = 1.14; 95% CI: 0.70-1.86; P = .59). However, S- demonstrated a significant reduction in operative time (Cohen d = 1.20; 95% CI: 0.62 to 1.78; P < .001) and intra-operative blood loss (Cohen d = 0.65; 95% CI: 0.52 to 0.77; P < .001).

Both S+ and S- aTSAs provide equivalent functional and clinical outcomes, with S- providing some potential benefits such as decreased intra-operative blood loss and operative time. This implant may be particularly beneficial in younger patients with preserved metaphyseal bone quality.