Kinematic and kinetic analysis of canine pelvic limb amputees at a trot
Date
2011
Authors
Hogy, Sara, author
Reiser, Raoul, advisor
Worley, Deanna, committee member
Haussler, Kevin, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
Osteosarcoma is the most common form of bone tumors in dogs. Treatment options include palliative or curative-intent options. Of the curative-intent treatments, the most common is amputation, due to lower cost and the ability to perform the procedure on all osteosarcoma patients irrespective of tumor location, as opposed to limb-sparing options which can only be used when the tumor is located at the distal radius or ulna of the thoracic limb. Overall, dogs with amputations adjust well to the loss of the limb; however, there still remains a subset of patients which do not. In this study, the ground reaction force kinetics and joint angular kinematics of pelvic limb amputees and four-legged dogs were compared to identify compensation strategies adopted by amputees after the loss of a pelvic limb. It was hypothesized that there would be increased flexion and extension of all limbs within the amputees, as well as increased spinal motion. In addition, it was hypothesized that there would be decreased vertical impulses in all limbs of amputees, as well as, decreased propulsion forces within the thoracic limbs of amputees, as compared to controls. The four-legged control population consisted of 24 dogs and the pelvic limb amputee population consisted of 12 dogs. Both populations had dogs of varying breeds. Ground reaction force data were captured using three serial force platforms while dogs were trotted down an over-ground walkway. Concurrently, joint angular kinematic data were captured by motion capture software using retroflective markers affixed to bony landmarks along the limbs and axial skeleton. Peak ground reaction forces and impulses were slightly different between pelvic limb amputees and four-legged dogs. Pelvic limb amputees had increased peak braking forces in the contralateral thoracic limb and increased peak propulsion in both the ipsilateral thoracic limb and remaining pelvic limb. In addition, amputees had increased peak vertical force and propulsion impulse in the remaining pelvic limb. Time to peak braking force was significantly decreased in all limbs of the amputees, while time to peak propulsion ground reaction force was increased in all limbs of the amputees. Limb kinematics of pelvic limb amputees were very similar to the kinematics of four-legged dogs. The only compensatory strategy adopted within the limbs of the amputee was increased range of motion of the hock joint within the remaining pelvic limb. However, the pelvic limb amputees had various spinal compensatory changes within the sagittal plane. Amputees had increased regional spinal motion about both the T1 and T13 markers and increased extension about the L7 marker, compared to four-legged controls. The motion of the spine in the horizontal plane varied only in the regional angular motion about the L7 marker. Overall, ground reaction force kinetic and joint angular kinematic gait analysis of pelvic limb amputees showed that there are various compensation strategies adopted by pelvic limb amputees to adjust for the loss of a limb. Combined, these compensation strategies allow for successful adaptation to a three-legged gait pattern after the removal of a pelvic limb. Clinically, this information will be valuable for determining factors related to adaptive strategies with pelvic limb amputees. This information can also be used to create a set of quantitative measures needed to classify canine amputees into adapted or poorly adapted gait parameters.