Work

More than half of shoulder vaccinations may end up in the subacromial space

Year: 2025

Type: article

Abstract: Shoulder Injury Related to Vaccine Administration (SIRVA) can occur as subacromial bursitis, frozen shoulder, or tendinopathy following deltoid intramuscular immunization. This study evaluated needle overpenetration into the subacromial space using a standard needle in 177 patients undergoing arthroscopic shoulder surgery from 2022 to 2024, with a median age of 55. Findings showed a mean needle length of 25.36 mm was required for subacromial penetration, occurring in 51.9% of cases. Significant associations with needle overpenetration included Body Mass Index (BMI), weight, deltoid thickness, fat thickness, and combined fat and deltoid thickness, all statistically significant (p < 0.05). These results suggest the standard needle length may be too long for most adults, increasing complication risks. To prevent subacromial injections, the study recommends vaccination guidelines to adopt a shorter 15 mm needle for most adults, ensuring proper vaccine delivery into the deltoid muscle and minimizing SIRVA risk.

Source: npj Vaccines

DOI: 10.1038/s41541-025-01279-7