[Purpose] For monitoring patients with knee osteoarthritis undergoing knee arthroplasty,
the Timed Up and Go and maximum walking speed tests are commonly used. To provide
appropriate peri-surgical rehabilitation, we evaluated the factors associated with
postsurgical changes in Timed Up and Go and maximum walking speed results. [Participants
and Methods] We enrolled 545 knee osteoarthritis patients undergoing either of the
following knee arthroplasties: conventional total knee arthroplasty, minimally invasive
total knee arthroplasty, and unicompartmental knee arthroplasty. Comfortable Timed Up and
Go, maximum Timed Up and Go, and maximum walking speed were measured 2 weeks before and
soon after surgery. Factors (gender, age, and surgical mode) that might influence changes
in test results were evaluated by multiple regression analysis and a two-factor
stratification diagram. [Results] Multiple regression analysis revealed that postsurgical
changes in comfortable/maximum Timed Up and Go and maximum walking speed results were
associated with age and surgical mode after adjustment for preoperative values. Two-factor
diagrams showed that the older the patient, the greater was the slowdown in the Timed Up
and Go test performed postoperatively. The levels of slowdown in the postoperative Timed
Up and Go and maximum walking speed tests were the smallest in those who underwent
conventional total knee arthroplasty, followed by those who underwent minimally invasive
and unicompartmental knee arthroplasty. Among patients whose preoperative Timed Up and Go
and maximum walking speed were slow, slowdown in Timed Up and Go was pronounced with age,
and slowdown in maximum walking speed was higher in conventional total knee arthroplasty.
[Conclusion] The changes in Timed Up and Go and maximum walking speed results 2 weeks
after knee arthroplasty depended on age and surgical modes. These findings are relevant
for the implementation of appropriate peri-surgical rehabilitation.
