Symptomatic Aseptic Loosening of a Short Humeral Stem Following Anatomic Total Shoulder Arthroplasty
These authors point out that the reported rate of aseptic humeral component loosening with standard-length stems is low (0.3%).
They reviewed 184 shoulders that received TSA with a grit-blasted, rectangular short humeral stem without ingrowth coating (Univers Apex; Arthrex; Naples, FL).
The average patient age was 62.1 years old and 57.1% were male.
65% had followup x-rays at one year after surgery. Twenty-three (12.5%) patients had a painful shoulder and radiographic concern for potential humeral loosening at a mean follow-up of 1.5 years.
At the time of publication, 13(7.1%) of these had undergone revision shoulder arthroplasty where a loose stem was confirmed.
All revisions underwent tissue culture; three cases were consistent with probable or possible periprosthetic infection at the time of revision arthroplasty.
The rate of symptomatic aseptic humeral loosening in this series was 10.9% with 5.4% undergoing revision surgery. Patients with symptomatic aseptic humeral loosening were more likely to be male (90.5%) than those patients without symptoms (52.8%; p<0.001). There were no differences in canal fit between patients with concern for symptomatic loosening and those with pain-free, stable implants.
These authors concluded that "the early humeral loosening rate for this stem design far outpaces previously reported rates and this study likely under-reports the true incidence of clinically-significant loosening as it only contains limited short-term follow-up."
Comment: This study does not provide evidence of the clinical value of this short stemmed humeral prosthesis in comparison to a standard length stem.
We have found that loose short stemmed humeral components can be successfully revised to an impaction allografted standard stem.
