Physical Activity Promotes Gait Improvement in Patients With Total Knee Arthroplasty.

BACKGROUND: The study aimed to examine whether the improvement in gait function after total knee arthroplasty (TKA) correlated with the amount of physical activity and whether both gait self-efficacy and gait function are predictors of the amount of physical activity up to 6 months after surgery. METHODS: Eighty-one patients were tested preoperatively and at the first and sixth postoperative months after TKA. Physical performance (timed up and go [TUG], sit to stand, muscle strength) and the modified gait efficacy scale scores were evaluated. The average amount of physical activity during the 6 postoperative months was measured with a pedometer with triaxial accelerometer. Stepwise multiple regression analyses were performed using TUG changes and postoperative physical activity. The discriminative properties of physical activity for improvement in gait function were subsequently investigated by applying a receiver operating characteristic curve analysis. RESULTS: The multiple regression analyses indicated that the amount of physical activity and the improvement in sit-to-stand time were important in predicting improvement in TUG scores after TKA, and postoperative physical activity up to 6 months was predicted by the modified gait efficacy scale and TUG scores at the first postoperative month. The receiver operating characteristic curve analysis suggests that with a cutoff point of 3053 steps/d, the amount of physical activity may be a good predictive factor for gait function after TKA. CONCLUSION: The clinical implications are that increases in physical activity can promote improvement in gait function after TKA and present with a solid numerical target for the recommended amount of physical activity.

Comprehensive geriatric assessment of effects of hospitalization and long-term rehabilitation of patients following lower extremity arthroplasty.

[Purpose] This study was performed to examine the effects of subacute physical therapy (PT) on activities of daily living (ADL), quality of life, and geriatric aspects of patients who underwent total knee arthroplasty (TKA) or total hip arthroplasty (THA). [Subjects] The subjects were TKA (n=56) and THA (n=39) patients who received PT on the first day of independent ADL (up to 2 weeks) and just prior to discharge (4 weeks). [Methods] The functional independence measure (FIM), grip strength, knee extension strength (KES), timed up and go (TUG) test, mini-mental state examination (MMSE), geriatric depression scale short form (GDS-15), fall efficacy scale (FES), and medical outcome study 8-item short-form health survey (SF-8) were used as outcome measure, and comorbidity involvement was also investigated. [Results] Improvements in FIM, KES, TUG, GDS-15, FES, and SF-8 scores were seen in both groups (effect size, 0.31-0.87). Poor PT effects were found for THA patients aged ≥65 years, for TKA and THA patients with an MMSE score ≤28, and for THA patients with two or more comorbidities. [Conclusion] Positive effects were seen in patients who received PT at 2-4 weeks after surgery. Thus, additional PT for approximately 2 weeks after the beginning of independent ADL may be beneficial.

Physical Activity Mediates the Relationship between Gait Function and Fall Incidence after Total Knee Arthroplasty.

The present study aims to examine (1) the preoperative factors that can predict postoperative falls, (2) whether postoperative physical activity (PA) mediates the relationship between fall incidence and gait function, and (3) whether postoperative PA levels are associated with fall risk in total knee arthroplasty (TKA) patients. Ninety-six patients (mean age: 72.0 ± 6.1 years) who were observed postoperatively for 6 months were selected. Timed up and go (TUG) was assessed as an indicator of gait function. Fall incidence and PA were investigated for 6 months post-TKA. The body mass index, history of preoperative falls, knee pain, knee extensor strength, range of motion in knee flexion, and modified gait efficacy scale were evaluated. Additionally, postoperative PA levels were categorized into three groups-low: <3,000, moderate: 3,000 to 4,000, and high: ≥4,000 steps/day. The relative fall incidence rate was calculated according to the total number of falls normalized for every 1,000 steps/day for 6 months postoperatively. Twenty-five (26.0%) of the 96 patients had at least one fall. The TUG, knee pain, and knee extensor strength were identified preoperatively as significant variables affecting postoperative falls. The mediated effects model revealed that postoperative fall incidence was predicted by preoperative TUG and postoperative PA. Postoperative PA was significantly associated with preoperative TUG. Moreover, both the preoperative TUG and postoperative PA were selected as significant variables for predicting fall incidence. Thus, postoperative PA mediates the relationship between gait function and fall incidence after TKA. Furthermore, the relative fall incidence rate associated with a low PA level was significantly higher than that associated with moderate and high PA levels. In conclusion, preoperative assessments of TUG performance, muscle strength, and knee pain were effective in predicting fall risk. Additionally, an increase in PA could contribute to reducing fall risk in TKA patients. Therefore, our results suggest that preoperative screening for fall predictors and managing postoperative PA could reduce the fall incidence in TKA patients.

Quantity and Quality of the Lower Extremity Muscles in Women with Knee Osteoarthritis.

The objective of the study described here was to compare lower extremity muscle quantity and quality between individuals with and those without knee osteoarthritis (OA). Twenty-one women with knee OA (mild, n = 8; severe, n = 13) and 23 healthy patients participated. Ultrasonography was used to measure muscle thickness (MT) and echo intensity (EI) of the rectus femoris, vastus intermedius, vastus lateralis, vastus medialis, biceps femoris, gluteus maximus, gluteus medius, gastrocnemius, soleus and tibialis anterior. MTs of the vastus medialis and vastus intermedius were smaller, and EIs of the vastus medialis, vastus intermedius, gluteus medius and tibialis anterior were larger, in the severe OA group compared than in the healthy group. Compared with the healthy group, the mild OA group had decreased MT and enhanced EI. Changes in quality and quantity occurring with knee OA progression differed among muscles. In the vastus medialis, change was observed from an earlier stage.