BACKGROUND: Musculoskeletal problems, or aromatase inhibitor-associated musculoskeletal syndrome, in the hands and wrists is a known side effect of aromatase inhibitor medication, often prescribed for 5years or more for breast cancer survivors. No studies were found on the effectiveness of hand therapy for breast cancer survivors experiencing aromatase inhibitor-associated musculoskeletal syndrome in the hands and wrists. PURPOSE: The primary objective of this study is to determine the effectiveness of hand therapy on reducing hand and wrist pain, improving grip strength, improving upper extremity function, and improving health related quality of life in breast cancer survivors diagnosed with aromatase inhibitor-associated musculoskeletal syndrome in the hands and wrists. STUDY DESIGN: Longitudinal case series. METHODS: A pre-post design was used to compare the results of standardized testing from initial evaluation to discharge. Participants were evaluated using standard hand therapy methods. Outcome measurements studied were pain levels, grip strength, upper extremity function, and breast cancer health related quality of life, measured with a patient-reported outcome measure specific to this population. A multimodal client centered treatment plan was utilized with each participant. Frequency and duration of the treatment was determined through collaboration with the participant. RESULTS: Thirty-two participants enrolled and 29 completed the study. Comparison of pre and post data for all four outcome measures revealed statistically significant improvements (p<
0.05). Cohen's d analysis demonstrated large effect for pain, moderate effects for upper extremity function and health related quality of life, and low effect for grip strength. Trigger finger was noted to be present in 62.1% of participants. CONCLUSIONS: This study demonstrates that hand therapy resulted in statistically and clinically significant improvement in pain, grip strength, upper extremity function, and health related quality of life. The results support the effectiveness of hand therapy for breast cancer survivors experiencing aromatase inhibitor-associated musculoskeletal syndrome in the hands and wrists.