Objective: To investigate the efficacy of tibial nerve blocking by percutaneous radiofrequency thermocoagulation and an ankle-foot orthosis on the walking ability of stroke patients with a spastic equinus or equinovarus foot. Design: A placebo-controlled randomized clinical trial with a 2 x 2 factorial design and with a 3-month follow-up. Setting: Outpatient clinic of a department of rehabilitation medicine. Subjects: Sixty stroke patients (17 women, 43 men) with a median age of 58 years and a median period of 34 months poststroke were allocated to one of four treatment groups. Main Outcome Measures: Changes in walking ability (measured with the Sickness Impact Profile category 'ambulation'; possible score range, 0% to 100%) and walking speed after 3 months. Results: With respect to walking ability, the efficacy of thermocoagulation as compared with placebo thermocoagulation was .56% (95% confidence interval [CI] -3.01% to 4.13%), whereas the efficacy of the ankle- foot orthosis as compared with the placebo ankle-foot orthosis was 2.72% (95% CI-.94% to 6.38%). To study the potential synergistic effect of both treatments, a multivariate model was used; interaction between both treatments was small, .83% (95% CI-6.73% to 8.40%). Analysis restricted to the compilers (n = 30) showed an in creased efficacy of thermocoagulation and a decreased efficacy of the ankle-foot orthosis. The changes in comfortable and maximal safe walking speed were less than .10m/sec and were neither clinically nor statistically significant (the median baseline values for the total group were .42m/sec and .56m/sec, respectively). Conclusion: No support was found for the beneficial effects of either thermocoagulation of the tibial nerve or a polypropylene ankle-foot orthosis in 5 degrees of dorsiflexion on the walking ability of stroke patients.