Upper Extremity Muscle Oxygenation Dynamics and Functional Performance in Breast Cancer Survivors

Persistent impairments in upper extremity function are well documented among breast cancer survivors even after completion of cancer treatment. These impairments are frequently attributed to fatigue and other treatment-related complications. Upper extremity function in patients undergoing breast cancer surgery may be affected by multiple factors, including surgical tissue trauma, axillary lymph node dissection or sentinel lymph node biopsy, radiation-induced fibrosis, pain, restricted shoulder range of motion, loss of muscle strength, and lymphedema. Muscle oxygenation may also be impaired through various mechanisms following breast cancer surgery and is considered one of the important microvascular mechanisms potentially underlying upper extremity functional impairments. However, muscle oxygenation has not been sufficiently investigated in this population. Existing studies have predominantly focused on lower extremity muscles, whereas changes in upper extremity muscle oxygenation have yet to be adequately investigated. This gap in the literature may limit the development and targeted implementation of appropriate exercise interventions and the identification of optimal exercise modalities aimed at improving upper extremity function in daily life, enhancing independence, facilitating participation in social and occupational activities, and ultimately improving quality of life among breast cancer survivors.

In this project, the investigators aim to investigate the relationship between tissue-level muscle oxygenation parameters and clinical measures of upper extremity function, including muscle strength, upper extremity functional capacity, and the score on the Disabilities of the Arm, Shoulder and Hand Questionnaire-Quick Version (QuickDASH). By examining these associations, the investigators intend to contribute to a better understanding of the pathophysiological mechanisms underlying functional impairments in breast cancer survivors and to provide a basis for the development of more effective and targeted rehabilitation protocols, including interventions designed to enhance microcirculation and aerobic exercise capacity.

Breast cancer survivors followed at the Breast Clinic of the Department of General Surgery at Pamukkale University and healthy individuals will be included in two study groups. Upper extremity muscle oxygenation and functional performance will be assessed using a hand-held dynamometer, near-infrared spectroscopy (NIRS), the six-minute pegboard and ring test, and the Disabilities of the Arm, Shoulder and Hand Questionnaire-Quick Version (QuickDASH).

By comparing upper extremity muscle oxygenation and functional performance between breast cancer survivors and healthy individuals, the findings of this project are expected to provide a better understanding of the muscle characteristics underlying upper extremity functional impairments in breast cancer survivors. These findings may contribute to the development and refinement of exercise interventions within rehabilitation programs and highlight the importance of selecting appropriate exercise modalities to improve upper extremity function in this population.