Trial Outcomes & Findings for Functional Resistance Training to Improve Knee Function After ACL Reconstruction (NCT NCT03282565)

Last Updated: 2022-01-18

Results Overview

Isometric quadriceps strength was measured with the knee at 60 degrees using an isokinetic dynamometer prior to the intervention and immediately after the intervention. Post-test minus pre-test change scores were calculated.

Recruitment status

COMPLETED

Study phase

Target enrollment

30 participants

Primary outcome timeframe

Pre-test measurements were taken at ~9-10 weeks after ACL reconstruction and Post-test measurements were taken at ~18-20 weeks after ACL reconstruction.

Results posted on

2022-01-18

Participant Flow

Participant milestones

Participant milestones
Measure	Functional Resistance Training With Brace Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Overall Study STARTED	10	10	10
Overall Study COMPLETED	10	8	8
Overall Study NOT COMPLETED	0	2	2

Reasons for withdrawal

Reasons for withdrawal
Measure	Functional Resistance Training With Brace Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Overall Study COVID-19 Research Shutdown	0	2	2

Baseline Characteristics

Functional Resistance Training to Improve Knee Function After ACL Reconstruction

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Functional Resistance Training With Brace n=10 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band n=10 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control n=10 Participants Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.	Total n=30 Participants Total of all reporting groups
Age, Continuous	18.8 years STANDARD_DEVIATION 6.2 • n=5 Participants	22.1 years STANDARD_DEVIATION 4.5 • n=7 Participants	20.4 years STANDARD_DEVIATION 5.6 • n=5 Participants	20.4 years STANDARD_DEVIATION 5.4 • n=4 Participants
Sex: Female, Male Female	6 Participants n=5 Participants	6 Participants n=7 Participants	6 Participants n=5 Participants	18 Participants n=4 Participants
Sex: Female, Male Male	4 Participants n=5 Participants	4 Participants n=7 Participants	4 Participants n=5 Participants	12 Participants n=4 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants	3 Participants n=4 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Black or African American	1 Participants n=5 Participants	2 Participants n=7 Participants	0 Participants n=5 Participants	3 Participants n=4 Participants
Race (NIH/OMB) White	9 Participants n=5 Participants	7 Participants n=7 Participants	8 Participants n=5 Participants	24 Participants n=4 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants
Region of Enrollment United States	10 participants n=5 Participants	10 participants n=7 Participants	10 participants n=5 Participants	30 participants n=4 Participants
Height	174 centimeters STANDARD_DEVIATION 11.2 • n=5 Participants	172.3 centimeters STANDARD_DEVIATION 7.9 • n=7 Participants	169.8 centimeters STANDARD_DEVIATION 9.0 • n=5 Participants	172.0 centimeters STANDARD_DEVIATION 9.4 • n=4 Participants
Mass	70.1 kilograms STANDARD_DEVIATION 10.5 • n=5 Participants	70.3 kilograms STANDARD_DEVIATION 12.2 • n=7 Participants	70.2 kilograms STANDARD_DEVIATION 13.3 • n=5 Participants	70.2 kilograms STANDARD_DEVIATION 12.0 • n=4 Participants
Time Since Surgery to Baseline Study Testing	8.9 weeks STANDARD_DEVIATION 2.6 • n=5 Participants	9.5 weeks STANDARD_DEVIATION 2.5 • n=7 Participants	10.3 weeks STANDARD_DEVIATION 3.1 • n=5 Participants	9.6 weeks STANDARD_DEVIATION 2.7 • n=4 Participants

PRIMARY outcome

Timeframe: Pre-test measurements were taken at ~9-10 weeks after ACL reconstruction and Post-test measurements were taken at ~18-20 weeks after ACL reconstruction.

Outcome measures

Outcome measures
Measure	Functional Resistance Training With Brace n=10 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band n=9 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control n=9 Participants Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Quadriceps Muscle Strength	.674 Nm/Kg Standard Error .124	.398 Nm/Kg Standard Error .130	.279 Nm/Kg Standard Error .130

SECONDARY outcome

Timeframe: Immediately after the intervention or approximately 18-20 weeks after ACL reconstruction

Quadriceps voluntary activation was measured using the burst superimposition technique and calculated using the central activation ratio (CAR). The CAR formula is calculated using the peak torque generated immediately prior to the delivery of the stimulus (or the maximum voluntary isometric contraction, MVIC) being divided by the peak torque generated as a result of the electrical stimulus (MVIC plus superimposed burst) and then multiplied by 100. Equation is: MVIC/(MVIC + superimposed burst) × 100. A CAR of 100 represents complete volitional quadriceps activation. Voluntary activation was quantified immediately after the intervenapproximately 9-10 weeks after the int from baseline to the end of intervention will be assessed and compared between groups.

Outcome measures

Outcome measures
Measure	Functional Resistance Training With Brace n=10 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band n=9 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control n=9 Participants Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Quadriceps Voluntary Activation	73.19 percentage of activation Standard Error 6.56	69.55 percentage of activation Standard Error 7.72	68.29 percentage of activation Standard Error 7.19

SECONDARY outcome

Timeframe: Pre-intervention values were recorded at ~9-10 weeks after ACL reconstruction and before the start of the intervention. Post-intervention values were recorded after the 8-week intervention (~18-20 weeks after ACL reconstruction)

The knee flexion angle (measured in degrees) during the stance phase was gathered for both limbs using three dimension motion capture and recorded while subjects walked overground. A knee flexion angle symmetry score was computed using the following formula: ensemble average of knee flexion angle of ACL limb minus the ensemble average of knee flexion angle of the non-ACL limb. The mean difference between pre-intervention and post-intervention (post minus pre) knee flexion symmetry scores were calculated for each group. Higher values suggest greater increases in knee flexion angle symmetry from pre-intervention to post-intervention.

Outcome measures

Outcome measures
Measure	Functional Resistance Training With Brace n=9 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band n=8 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control n=9 Participants Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Knee Flexion Angle Symmetry	3.230 Angle Symmetry (degrees) Interval 0.658 to 5.803	0.556 Angle Symmetry (degrees) Interval -0.857 to 1.97	0.846 Angle Symmetry (degrees) Interval -0.917 to 2.608

SECONDARY outcome

Timeframe: Pre-intervention scores were recorded prior to the start of the intervention and approximately 9-10 weeks after ACL reconstruction. Post-intervention scores were recorded after the 8 week intervention or approximately 18-20 weeks after ACL reconstruction

The sagittal plane knee moment (units Nm) during the stance phase was gathered for both limbs using three dimensional motion capture and recorded while subjects walk overground. A symmetry score was computed using the following formula: ensemble average of the knee moment of the ACL limb (Nm) - ensemble average of the knee moment of the non-ACL limb (Nm). The mean difference between pre-intervention and post-intervention knee moment symmetry scores (post minus pre) were calculated for each group. Higher values represent the greater increases in knee moment symmetry from pre-intervention to post-intervention.

Outcome measures

Outcome measures
Measure	Functional Resistance Training With Brace n=9 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: A customized knee brace was strapped to the leg and applied resistance during knee flexion and extension while subjects walked on a treadmill.	Functional Resistance Training With Elastic Band n=8 Participants Participants received functional resistance training while walking on a treadmill 2-3 times a week for 8 weeks. Functional Resistance Training: An elastic band strapped to the ankle provided resistance during knee extension while subjects walked on a treadmill.	Control n=9 Participants Participants walked on a treadmill without an applied resistance 2-3 times a week for about 8 weeks. Control: A knee brace was strapped to the leg and did not apply resistance while subjects walked on a treadmill.
Knee Moment Symmetry	.0144 Moment Symmetry (Nm) Interval -0.057 to 0.086	0.132 Moment Symmetry (Nm) Interval 0.0408 to 0.224	-0.042 Moment Symmetry (Nm) Interval -0.078 to -0.0074

Adverse Events

Functional Resistance Training With Brace

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Functional Resistance Training With Elastic Band

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Control

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Riann Palmieri-Smith

University of Michigan

Phone: 734-615-3154

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place