Motor branch block of the rectus femoris: Its effectiveness in stiff-legged gait in spastic paresis

Objective: To verify the efficacy of motor branch block of the rectus femor is for stiff-legged gait in spastic patients. Design: Before-after treatment trial. Setting: University hospital physical medicine and rehabilitation departmen t outpatient clinic. Patients: Thirty-one adult spastic patients with stiff-legged gait. Intervention: Motor branch block of the rectus femoris with 2% lidocaine an d 5% phenol. Outcome Measures: Subjective assessment of gait performance by patients the mselves and objective assessment of gait speed and sagittal knee kinematics . Results: Seventy-four percent (23/31) of patients felt an improvement (impr oved knee bending, disappeared toe dragging) after nerve block with lidocai ne. Sixteen of 17 patients with an abnormal swing phase activity of the rec tus femoris without that of the vastus medialis or lateralis and 20 of 23 p atients with a sufficient hip flexor strength expressed an improvement subj ectively. Gait analysis showed increased maximal knee flexion at swing phas e and increased slope of knee flexion curve at toe off (p < .05). Phenol bl ock was performed in 19 of 23 patients who had had a subjective improvement in their gait performance after nerve block with lidocaine. Gait speed, ma ximal knee flexion angle at swing phase, and slope of knee flexion curve at toe off increased significantly after phenol block (p < .05). Conclusion: Motor branch block of the rectus femoris can be an effective tr eatment in stiff-legged gait. Its effect is varied with hip flexor strength and dynamic electromyographic findings of quadriceps.