Date of Award
Master of Engineering Science
Dr. James Johnson
Dr. Graham King
Techniques have evolved for quantifying human tendon and ligament forces in the lower extremity; however, custom developed systems for the upper extremity, particularly the elbow, are not well described. Consequently, ligament forces of the human elbow joint have not been reported. Knowledge of the magnitudes of tension of the primary valgus stabilizer, the anterior bundle of the medial collateral ligament (AMCL), would allow for an improved understanding of the load environment of this tissue. Mechanisms of AMCL injury include chronic high intensity overuse, radial head fracture, and elbow dislocations. This work focused on the design and development of a custom designed E- form frame buckle transducer to quantify AMCL tension in vitro. To understand the basic biomechanical characteristics of the AMCL, a series of in vitro studies employing this device were conducted. The specific objectives of this work were: (1) to quantify the magnitude of AMCL tension through the arc of elbow flexion; (2) to determine the effect of wrist flexor muscle loading on the magnitude of AMCL tension through the arc of elbow flexion; and (3) to evaluate the effect of radial head excision and arthroplasty on
the magnitude of AMCL tension through the arc of elbow flexion. The chief findings were: (1) AMCL tension increased with increasing angles of elbow flexion (i.e. AMCL tension was greater at full flexion than at full extension); (2) increased wrist flexor muscle loading caused AMCL tension levels to decrease; and (3) radial head excision increased AMCL tension levels, whereas metallic radial head arthroplasty restored near normal AMCL tension levels. Furthermore, for all investigations, AMCL tension levels were greater with the arm oriented in the valgus position than in the dependent (i.e. vertical) position. Improved knowledge of AMCL tissue biomechanics will allow for the design and evaluation of improved methods of AMCL repair/reconstruction and rehabilitation, and assist in the development of an artificial AMCL and in vitro
biomechanical models of the elbow. Furthermore, this transducer will permit numerous additional projects to be explored that will investigate the ligament and soft tissue loading at the elbow, shoulder, and wrist.
Fay, Katherine E., "DESIGN, DEVELOPMENT, AND APPLICATION OF A TRANSDUCER TO QUANTIFY TENSION IN THE MEDIAL COLLATERAL LIGAMENT OF THE ELBOW" (2009). Digitized Theses. 3928.