Shoulder impairments and their association with symptomatic rotator cuff disease in breast cancer survivors

Over 2.6 million breast cancer survivors currently reside in the United States. While improvements in the medical management of women diagnosed with breast cancer have resulted in a 5-year survival rate of 89%, curative treatments are associated with a high prevalence of shoulder and arm morbidity, which, in turn, can negatively impact a woman's quality of life. Breast cancer survivors frequently experience shoulder and arm pain, decreased range of motion, muscle weakness, and lymphedema. These symptoms can lead to difficulties with daily activities ranging from overhead reaching and carrying objects to caring for family and returning to work. Despite health care professionals awareness of these problems, a significant number of breast cancer survivors are confronted with long-term, restricted use of their affected shoulder and upper extremity. This problem may partially be explained by: (1) an incomplete understanding of relevant impairments and diagnoses associated with shoulder/arm pain and limited upper extremity use, and (2) the limited effectiveness of current rehabilitation interventions for managing shoulder pain and decreased upper extremity function in breast cancer survivors. Because breast cancer treatment directly involves the neuromusculoskeletal tissues of the shoulder girdle, it is understandable why breast cancer survivors are likely to develop shoulder girdle muscle weakness and fatigue, decreased shoulder motion, altered shoulder girdle alignment, and lymphedema. These impairments can be associated with diagnoses such as post-mastectomy syndrome, adhesive capsulitis, myofascial dysfunction, and brachial plexopathy, all of which have been reported among breast cancer survivors. It is our belief that these impairments also put women at risk for developing symptomatic rotator cuff disease. In this paper we set forth the rationale for our belief that breast cancer treatments and subsequent impairments of shoulder girdle neuromusculoskeletal tissues place breast cancer survivors at risk for developing symptomatic rotator cuff disease. Additionally, we identify knowledge gaps related to the current understanding of relevant shoulder girdle impairments and their association with symptomatic rotator cuff disease in breast cancer survivors. Ultimately, information from studies designed to meet these gaps will provide a scientific basis for the development of new, or refinement of existing, examination, intervention, and prevention techniques, which should lead to improved clinical outcomes in this population.