| Description |
By the year 2030, there is expected to be a 6-fold increase in the number of annual total knee arthroplasty (TKA) surgeries. The growing demand for TKA has highlighted the need to develop improved measures for identifying modifiable factors that may be linked to poor physical performance and long-term outcomes following TKA. This body of work focuses on factors that may be linked to poor TKA outcomes, including the following: 1) physiological factors such as high sensitivity C-reactive protein (hs-CRP) and cytokines and 2) post-TKA functional outcomes that may be linked to future mobility deficits and risk of falling. A total of 47 subjects with osteoarthritis (OA) scheduled for TKA, and 11 controls without OA were assessed in two separate clinical studies. Study #1 encompassed 31 TKA subjects stratified by hs-CRP: 15 with hs-CRP <1.0 mg/L and 16 with hs-CRP >4.0 mg/L. Study #2 included 16 subjects with OA scheduled for TKA and 11 controls without OA. In Study #1, synovial fluid (SF) and bone sections were sequestered during surgery; 12 cytokines were measured in SF and histological measures of inflammation were assessed in bone sections. Relationships between cytokines and hs-CRP were assessed. In Study #2, pre- and postoperative assessments of submaximal muscle force steadiness (MFS) and variability during gait and stair stepping were evaluated and compared to healthy controls. Study #1 showed the presence of lymphocytes in 10 synovium and one bone sample (all from high hs-CRP group), and significant correlations between hs-CRP and cytokines interleukin (IL)-5 and IL-10. Study #2 showed that quadriceps MFS was significantly more impaired in the TKA subjects preoperatively, but not postoperatively compared to controls, and significantly improved between the pre- and postoperative visits. Additionally, there was a significant reduction in variability during gait between pre- and postoperative visits, but not during stair stepping. The results suggest that inflammatory mechanisms contribute to OA progression, with hs-CRP being a possible predictive variable, combined with other comorbidities, of postoperative function. Further, postoperative functional measures such as MFS and variability during gait and stair stepping may provide rehabilitation targets for individuals following TKA that may predict future falls and declines in functional mobility. |
