Abstract
Shoulder pain is a common symptom after intramuscular vaccination. However, only a few cases of shoulder joint injury have been reported after coronavirus disease 2019 vaccination. A 52-year-old woman experienced clinically significant pain in the left shoulder joint after receiving the first dose of a coronavirus disease 2019 vaccine. She neglected the shoulder pain, hoping that it would spontaneously improve without medical attention. However, the pain continued with obvious limitations in shoulder movement and function. After 8 months, she presented to the outpatient clinic with a frozen left shoulder. Such rare consequences of vaccinations, known as shoulder injury related to vaccine administration, can be prevented by using an appropriate needle gauge and length according to the patient's sex and weight with the correct injection site away from shoulder structures.