Table 1.

Study characteristics.

Study	Participants	Intervention	Control	Variables	Conclusions
RCT pilot 33	24 patients undergoing TKA from 65 to 75 years	N = 12 Standard rehabilitation (3 times per week for 4 weeks) + MI exercises (15-min sessions)	N = 12 Standard rehabilitation (3 times per week for 4 weeks) + Neutral activities (15-min sessions)	-Quadriceps strength -Knee maximal flexion during swing phase -Timed Up and Go Test	MI plus standard rehabilitation improves strength and functional recovery in patients with TKA
RCT pilot 34	20 patients undergoing TKA from 65 to 75 years	N = 10 Standard rehabilitation (3 times per week for 4 weeks) + MI exercises (15-min sessions)	N = 10 Standard rehabilitation (3 times per week for 4 weeks) + Neutral activities (15-min sessions)	-Quadriceps strength -Knee flexion ROM -Timed Up and Go test -Pain intensity	MI combined to standard rehabilitation improves quadriceps strength and knee flexion ROM in patients with TKA
RCT 39	34 patients undergoing bilateral TKA from 50 to 85 years	N = 17 Standard rehabilitation (4 weeks) + MI exercises (15-min sessions 5 days per week)	N = 17 Standard rehabilitation (4 weeks)	-Quadriceps strength	MI plus standard rehabilitation improves strength and reduces its loss and gait speed in patients with TKA 4 weeks after surgery
RCT 35	26 patients undergoing TKA from 50 to 85 years	N = 13 Standard rehabilitation (5 times a week, 2 times per day for 4 weeks) + MI exercises (2 sets of 25 repetitions)	N = 13 Standard rehabilitation (5 times a week, 2 times per day for 4 weeks)	-Strength -ROM -Timed Up and Go test -Pain intensity	The addition of MI to physical therapy rehabilitation preserved levels of strength and subjective measures of physical function
RCT 36	48 patients undergoing TKA from 59 to 73 years	N = 24 Standard rehabilitation + MI training (2 30-min sessions per day, every day along 11 days)	N = 24 Standard rehabilitation + Training based on the enhancement of non-motoric cognitive functions (2 30-min sessions per day, every day along 11 days)	-Timed Up and Go test -Knee flexion ROM Pain intensity	MI training combined to standard physical therapy rehabilitation may improve gait and limit new falls in the long term in patients with recent TKA in the post-surgery acute phase
RCT pilot 37	10 patients undergoing unilateral TKA from 50 to 80 years	N = 4 Standard rehabilitation (3 times per week for 2 months) + 10 mins of MI + Exercise programme	N = 6 Standard rehabilitation (3 times per week for 2 months) + Exercise programme	- Knee flexion ROM - Pain intensity	MI plus standard rehabilitation after TKA may improve knee flexion ROM and function
RCT 38	24 patients undergoing TKA from 60 to 85 years	N = 12 Standard rehabilitation (5 30-min sessions + Exercise programme mentally performed)	N = 12 Standard rehabilitation (5 30-min sessions + Exercise programme physically performed	-Knee flexion ROM -Pain intensity -Disability (self-reported)	MI combined to early physical therapy rehabilitation improves disability but no ROM in patients with TKA

MI, motor imagery; RCT, randomised controlled trial, ROM, range of motion; TKA, total knee arthroplasty.