Shoulder Stiffness: Quantification of Overuse Injury in Competitive Swimmers

Wednesday, June 7, 2017

11:00 AM-1:00 PM

BIOMED Master's Thesis Defense

Title:
Shoulder Stiffness: Quantification of Overuse Injury in Competitive Swimmers

Speaker:
Reed Vennel, MS Candidate, School of Biomedical Engineering, Science and Health Systems

Advisor:
Joseph Sarver, PhD, Associate Teaching Professor, School of Biomedical Engineering, Science and Health Systems

Abstract:
Overhead athletes, and swimmers in particular, are highly susceptible to shoulder injuries (Hibberd & Myers, 2013). Collegiate swimmers complete an average of between 10 and 14 kilometers every day they practice, which assuming 10 stroke cycles per 25-meter length, gives over 4000 revolutions forced upon the shoulders each day of practice (Tate et al., 2015; Hibberd & Myers, 2013). Furthermore, the shoulder transmits 90% of the force used to propel swimmers through the water, resulting in frequent overuse injury, broadly classified as “Swimmer’s Shoulder. ”

Estimates of the prevalence of shoulder pain amongst competitive swimmers range between 40% and 91% (Tate et al., 2012). Beyond being uncomfortable, this pain is associated with stiffness, reduced range of motion, and increased risk of serious injury, such as rotator cuff tears (Ma, 2015). The condition is thought to be caused by compensation for fatigue during long swim practices, and as a result treatment focuses on strengthening and stretching the affected tissues in an attempt to reduce the pain and the stiffness of the shoulder. However, stiffness is currently a qualitative assessment, based on the therapists perceived resistance to motion.

Most often, clinical studies equate an increase or decrease in the range of motion, as a decrease or increase in stiffness. However, no device previously existed which was capable of recording the torque required to rotate the shoulder, allowing quantification of the rotational stiffness of the shoulder.

Previously a senior design group adapted a device developed for animal studies to measure shoulder stiffness in internal and external rotation in humans (Sarver, 2015). However, this device was incapable of capturing the full range of internal and external rotation; did not securely attach to the arm, and was excessively heavy. The objectives of this project, therefore, were to revise the shoulder stiffness device (STROM) and to use it to assess shoulder stiffness in swimmers before and after various forms of exercise.

Contact Information

Ken Barbee
215-895-1335
barbee@drexel.edu