Abstract
OBJECTIVE: Prolonged immobilization of joints after distal radius fracture (DRF) causes cerebral disuse-dependent plasticity (DDP) and deterioration of upper extremity function. Action observation therapy (AOT) can improve DDP. TRIAL DESIGN: This nonrandomized controlled trial (UMIN 000039973) tested the hypothesis that AOT improves hand-use difficulties during activities of daily living in patients with DRF. METHOD: Right-handed women with volar locking plate fixation for DRF were divided into AOT and Non-AOT groups for a 12-week intervention. The primary outcome was difficulty in using the fractured hand, assessed with the Japanese version of the Patient-related Wrist Evaluation (PRWE). The secondary outcomes were range of motion (ROM) of the injured side and gap between measured ROM and patient-estimated ROM. The survey was administered immediately post operation and at postoperative weeks 4, 8, and 12. The AOT group used a head-mounted display and three-dimensional video during ROM exercises. The Non-AOT group used active ROM exercises alone. A generalized linear model (GLM) was used to confirm interactions and main effects by group and time period, and multiple comparisons were performed. RESULTS: Thirty-five patients were assigned to the AOT group (n = 18, median age, 74 years) or the Non-AOT group (n = 17, median age, 70 years). In the GLM, PRWE Total, PRWE Specific, and PRWE Usual scores revealed interactions between groups and periods. The post-hoc test revealed that the PRWE Specific scores (z = 3.43, p = 0.02) and PRWE Usual scores (z = 7.53, p<0.01) were significantly lower in the AOT group than in the Non-AOT group at 4 weeks postoperatively, whereas PRWE Total scores (z = 3.29, p = 0.04) were lower at 8 weeks postoperatively. CONCLUSIONS: These results suggested that AOT can improve hand-use difficulties in right-handed women after DRF surgery. AOT positively affects the motor imagery of patients with DRF and can reverse the patient's perceived difficulty in using the fractured hand during rehabilitation.