Benefits for Intense Exercise Started 3 Months Post-TKR
By medpagetoday.com
A comprehensive behavioral intervention (CBI) that incorporates intensive physical activity starting 3 months after total knee replacement (TKR) relieves knee pain and improves physical function and physical activity compared with a standard exercise program.
In the pilot study, patients randomized to CBI were faster in stair-climb and chair-stand tests from baseline to 6 months, while controls showed no change in the stair-climb test and only a slight increase in the chair-stand test, found Sara R. Piva, PT, PhD, co-director of the Physical Therapy Clinical and Translational Research Center of the University of Pittsburgh Medical Center-Rehabilitation Institute, and colleagues.
Writing online in Arthritis Care & Research, the team said, "The CBI is feasible and appears to be effective in improving physical function and physical activity as compared to a standard of care exercise program at a later stage, post-TKR. Larger pragmatic randomized trials should confirm the results of this study."
Persistent functional limitations combined with physical inactivity post-TKR "are major public health concerns and precursors of further comorbidities," the researcher noted.
The team developed a CBI that combines intense exercises with promotion of physical activity to be implemented 3 months post-TKR. The CBI was developed to be used after surgical healing to enable the performance of sufficiently intensive exercise to reverse long-lasting functional limitations that persist after TKR.
In the two-group, single-blind study, the CBI program was tested in a randomized manner in 44 patients ages 50 and older. CBI consisted of high-intensity exercise comprised of endurance, lower extremity strengthening, and skilled exercises (i.e., chair rises, stair climbing, and bilateral and unilateral mini-squats) in addition to interactive education. Endurance training consisted of 20 minutes of treadmill walking, maintaining the intensity between 50% and 75% of the age-estimated maximal heart rate. Strength training was performed at 60% to 80% of one-repetition maximum.
The standard-care group program was similar, without the education component, but endurance training was performed at 40% to 50% of the age-estimated maximal heart rate and strength training at 40% to 50% of one-repetition maximum.
Time commitments between the two groups were comparable, the researchers reported, and attendance at the supervised exercise sessions was similar in both groups, with an average adherence of 11.5 out of the 12 sessions (96%) in each group.
The CBI group had a greater reduction in pain score on the 5-item Western Ontario and McMaster Universities Osteoarthritis (WOMAC) pain subscale compared with the control group; the change in WOMAC pain score was -1.7 (95% CI -3.0 to -0.4) in the CBI arm versus -0.3 (95% CI -1.5 to 1.0) in the control arm (P= 0.035).
The CBI group also had more improvement compared with the standard exercise group in physical function as measured by the RAND-Physical Function (20.2 versus 6.8, P=0.017), which assesses physical function based on 10 activities, and on the single-leg stance test (2.0 versus -1.9, P=0.037). "From baseline to 6 months the CBI group became 4.6 and 2.2 seconds faster in the stair-climb and chair-stand tests, respectively, while the standard-care exercise group showed no change in the stair-climb test (0.1 seconds) and a slight increase in the chair-stand test (0.6 seconds)," the investigators wrote. Other outcome measures between the two groups were not significantly different.
More participants in the CBI group had their physical function increased above the minimum clinically important improvement compared with the standard-care exercise group. The rates of increase above the minimum clinically important improvement in the CBI group ranged from 24% on the 6-minute walk test and gait speed to 76% on the WOMAC-Physical Function, whereas the rates in the standard-care group ranged from 5% on the single-leg stance test to 60% on the WOMAC-Physical Function.
Almost half (47%) of participants in the CBI arm had an improvement in physical activity above the minimum clinically important improvement compared with 26% in the standard-exercise group.
More patients in the CBI group were classified as responders of physical function compared with the standard-care exercise group (81% versus 45%, respectively). Moreover, 38% of those in the CBI group were responders of the combined domains of physical function and physical activity compared with 15% of the standard-care exercise group.
Among the limitations noted by the authors were the lower body mass index of the study sample compared with the general population undergoing TKR (30.3 versus 32.4, respectively), and the lack of blinding to the group assignments. In addition, the session length was not recorded and may not have been equal between the two groups, the researchers stated.
Source: http://www.medpagetoday.com/rheumatology/arthritis/63561