Background
Approximately 40%(1) of breast cancer survivors have a postmastectomy breast reconstruction which restores the natural appearance of the breast and improves the psychosocial quality of life. However, these benefits come at a high functional cost to the upper extremity as key shoulder muscles are disinserted to achieve a positive cosmetic outcome. A widely used technique is a pedicled myocutaneous latissimus dorsi (LD) flap, during which the LD is disinserted from its attachments at the spine, scapula and pelvis, and the flap is transposed to the chest wall underneath the armpit(2).LD is one of the most powerful muscles in the human body, serving key roles in humeral(3) and scapular(4) mobility. As several shoulder muscles have overlapping lines of action(3), a clinical assumption is that the LD is expendable(5) and that the other shoulder muscles will compensate for the lack of it. Due to the lack of objective tools, clinicians currently assess shoulder function with goniometers during range of motion (ROM) tasks, manual muscle tests, and use self-reported questionnaires to assess patient's ability to perform certain upper extremity activities. However, these tools are not sensitive enough to detect subtle to moderate changes in shoulder function, cannot detect compensation in the neuromuscular system, and cannot be used to objectively assess the performance of real-life tasks. For example, despite the recovery of ROM months to a year following LD flap, women continue to have shoulder weakness(6), muscle fatigue(7), and difficulties performing daily, work, and/or athletic activities(8) years following surgery. These deficits may be a result of chronic neuromuscular compensations and lead to a further shoulder injury(9). Therefore, there is an urgent clinical need to introduce objective and more sensitive tools to monitor, track, and identify neuromuscular pathophysiology behind poor shoulder function reported in women following LD flap. Dr. Tea Lulic is a Research Scientist in the Department of Clinical and Experimental Sciences at the Università Degli studi di Brescia (Brescia, Italy). She completed her Ph.D. degree in Kinesiology at the University of Waterloo (Waterloo, Canada) and a postdoctoral fellowship at the University of Michigan (Michigan, USA). She has extensive experience in neuromechanical control of the shoulder complex with expertise in electromyography, motion tracking, and ultrasound shear-wave elastography. In 2018, Dr. Lulic-Kuryllo was the finalist for the American Society of Biomechanics Clinical Biomechanics Award for her work on the effects of radiation on pectoralis major neuromuscular control. Her research interests are in neuromuscular shoulder function in healthy and compromised populations, specifically following breast cancer treatment and breast reconstruction.
Dr. Tea Lulic is a Research Scientist in the Department of Clinical and Experimental Sciences at the Università Degli studi di Brescia (Brescia, Italy). She completed her Ph.D. degree in Kinesiology at the University of Waterloo (Waterloo, Canada) and a postdoctoral fellowship at the University of Michigan (Michigan, USA). She has extensive experience in neuromechanical control of the shoulder complex with expertise in electromyography, motion tracking, and ultrasound shear-wave elastography. In 2018, Dr. Lulic-Kuryllo was the finalist for the American Society of Biomechanics Clinical Biomechanics Award for her work on the effects of radiation on pectoralis major neuromuscular control. Her research interests are in neuromuscular shoulder function in healthy and compromised populations, specifically following breast cancer treatment and breast reconstruction.