Short-Term Efficacy of Integrating the Easy-Flex Device With Inpatient Rehabilitation in Individuals With Total Knee Arthroplasty: Insights From a Single-Blind Randomized Controlled Trial

To determine the effect of Easy-Flex as an adjunct to standard inpatient rehabilitation on clinical and functional outcomes. Prospective randomized controlled trial. Outpatient clinic and research laboratory. A total of 44 patients were randomized to the Easy-Flex Group (EFG) or Control Group (CG). A rehabilitation program averaging 50-60 minutes per day was implemented for the patients with CG. In the EFG, in addition to 30-40 minutes of exercise with the Easy-Flex, the rehabilitation program applied to the CG was integrated with reduced sets and repetitions, with an average duration of 20 minutes. All interventions were performed under the supervision of a physiotherapist during hospitalization. After discharge, both groups received the same home exercise program. The primary outcome is the flexion and extension range of motion (ROM). The secondary outcomes include the Numeric Pain Rating Scale (NPRS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Five Times Sit-to-Stand Test (5-TSST), 10-Meter Walking Test (10-MWT), Short Form (SF)-12v2, and Global Rating of Change scale. After 6 weeks, the overall group-by-time interaction for the 2 × 3 mixed-model analysis of variance was found to be significant for flexion ROM (P=.005), NPRS-rest (P=.04), NPRS-activity (P=.01), 10-MWT (P=.003), WOMAC (P=.021), and SF-12 physical component summary (PCS) (P=.032) in favor of EFG exercising with Easy-Flex in addition to standard rehabilitation. The between-group differences in favor of the EFG were −8.0° knee ROM, 1.35-1.5 points for pain intensity, and 0.12 m/s for gait speed. Furthermore, differences favoring EFG in NPRS-rest, 10-MWT speed, and SF-12 PCS were greater than the reported minimum clinically important difference. Incorporating Easy-Flex into standard physical therapy can be a beneficial, safe, and effective approach in clinical practice, as patients undergoing total knee arthroplasty typically prioritize improving their quality of life by reducing pain and increasing ROM.