Yuri Yoshida, MS. - Dissertation Proposal Defense
Gait Performance for Individuals after Total Knee Arthroplasty: A Longitudinal Analysis
Faculty Advisor: Lynn Snyder-Mackler, P.T., Sc.D., F.A.P.T.A._
Committee members:_
Christopher A. Knight, Ph.D.
Todd D. Royer, Ph.D.
Stephanie C. Petterson, Ph.D.
Abstract:
Total knee arthroplasty (TKA) is one of the most common surgeries performed at around 500,000 in
2004. Successful outcomes for TKA have been reported with pain reduction as well as high survivorship
over 10 years. Individuals after TKA also alter functional performance with atypical joint movements
compared to the healthy individuals. "When will I walk normally?" is one of the questions that candidates
before TKA are the most concerned with. On the other hand, the prognosis of gait patterns for individuals
after TKA seems not to be optimistic. Quadriceps weakness is one of the primary post-operative
impairments that affect functional status for individuals after TKA. A total joint arthroplasty due to
secondary OA progression following unilateral TKA most often occurred in the contralateral hip and knee
because they are the primary joints compensating for lower knee extension moment on the operated limb
during daily activities. The purpose of this investigation is to determine typical gait patterns for individuals
after TKA.
Increasing quadriceps strength after TKA has been established, but how individuals after TKA utilize
quadriceps strength during walking is still underinvestigated. Weaker quadriceps strength likely
contributes to overloading on the other joints instead of the lower knee extension moment on the
operated limb resulting in abnormal gait patterns. Systematic longitudinal study of gait analysis with
assessments of how quadriceps strength affects the knee function during walking will impact rehabilitation
by not only educating patients before and after TKA but also perhaps decreasing the risk of complications
after TKA.
Four studies will be undertaken for individuals after TKA and age-matched healthy individuals. The
purpose of the first study is to determine a relationship between asymmetric gait patterns and asymmetric
quadriceps strength in individuals 3 months, 1 year and 3 years after TKA. We hypothesize that
individuals after TKA will demonstrate asymmetric gait patterns due to asymmetric quadriceps strength in
early postoperative phase, but the gait patterns will improve along enhanced quadriceps strength on the
operated limb. The second and third studies are to investigate whether quadriceps weakness on the
operated limb affects abnormal joint loading patterns with interfaced electromyography results compared
to age (and gender)-matched healthy control group. We hypothesize that individuals after TKA will
demonstrate stiffening knee strategy and using greater hip extensor moment during loading response
compared to age-matched healthy individuals. The fourth study is to determine whether the gait
abnormalities that are indicated in the previous studies would be remarkable only unilateral TKA or it
could happen on simultaneous bilateral TKA to discuss a different possibility of secondary knee
osteoarthritis on the joints. We hypothesized that individuals after bilateral TKA will demonstrate better
functional status and more symmetrical gait patterns compared to unilateral TKA.