Objective: To evaluate the effect of extracorporeal shock wave therapy (ESWT) on lower limb spasticity in subacute stroke patients.
Methods: We studied thirty hemiplegic subacute stroke patients with ankle plantar flexor spasticity. ESWT was applied for 1 session/week, with a total of 3 sessions at the musculotendinous junction of medial and lateral gastrocnemius muscles. Patients were evaluated both clinically and biomechanically at baseline, after sham stimulation, and at immediately 1 week and 4 weeks after ESWT. For clinical assessment, Modified Ashworth Scale (MAS), clonus score, passive range of motion of ankle, and Fugl-Myer Assessment for the lower extremity were used. A biomechanical assessment of spasticity was conducted by an isokinetic dynamometer. Two parameters, peak eccentric torque (PET) and torque threshold angle (TTA), were analyzed at the velocities of 60°/sec, 180°/sec, and 240°/sec.
Results: After sham stimulation, there were no significant changes between each assessment. MAS and PET (180°/sec and 240°/sec) were significantly improved immediately and 1 week after ESWT. However, these changes were not significant at 4 weeks after ESWT. PET (60°/sec) and TTA (60°/sec, 180°/sec, and 240°/sec) were significantly improved immediately after ESWT. Yet, these changes were not significant at 1 week and 4 weeks after ESWT as well.
Conclusion: Lower limb spasticity in subacute stroke patients was significantly improved immediately after ESWT. Although the therapeutic effect of ESWT reduced with time and therefore was not significant at 4 weeks after ESWT, the degree of spasticity was lower than that of the baseline. Future studies with a larger sample of patients are warranted in order to verify the protocols which can optimize the effect of ESWT on spasticity.
Keywords: High-energy shock waves; Muscle spasticity; Stroke.