Effects of motor imagery on hand function during immobilization after flexor tendon repair.

OBJECTIVE To determine whether motor imagery during the immobilization period after flexor tendon injury results in a faster recovery of central mechanisms of hand function. DESIGN Randomized controlled trial. SETTING Tertiary referral hospital. PARTICIPANTS Patients (N=28) after surgical flexor tendon repair were assigned to either an intervention group or a control group. INTERVENTION Kinesthetic motor imagery of finger flexion movements during the postoperative dynamic splinting period. MAIN OUTCOME MEASURES The central aspects of hand function were measured with a preparation time test of finger flexion in which subjects pressed buttons as fast as possible following a visual stimulus. Additionally, the following hand function modalities were recorded: Michigan Hand Questionnaire, visual analog scale for hand function, kinematic analysis of drawing, active total motion, and strength. RESULTS After the immobilization period, the motor imagery group demonstrated significantly less increase of preparation time than the control group (P=.024). There was no significant influence of motor imagery on the other tested hand function (P>.05). All tests except kinematic analysis (P=.570) showed a significant improvement across time after the splinting period (P</=.001). CONCLUSIONS Motor imagery significantly improves central aspects of hand function, namely movement preparation time, while other modalities of hand function appear to be unaffected.