Treatment outcome of local injection of botulinum toxin for claw toe: Differences between cerebral hemorrhage and infarction.

[BACKGROUND] Some patients with post-stroke claw toe respond well to botulinum toxin (BoNT) treatment while others do not. This study was designed to assess the impact of stroke type (cerebral hemorrhage and cerebral infarction) on the outcome of BoNT treatment for claw toe.

[METHODS] We retrospectively examined the medical records of patients who received local BoNT (onabotulinumtoxin A) injections into the flexor hallucis longus (FHL) and flexor digitorum longus (FDL) muscles. All patients suffered stroke-related leg paralysis and spasticity.

[RESULTS] The study participants were 58 patients (mean age, 61.4 ± 10.3 years, ± SD) with time since stroke of 6.7 ± 4.4 years. The stroke type was cerebral hemorrhage (n = 38) and cerebral infarction (n = 20). After a total of 124 BoNT administrations with medical records entries on the subjective symptoms, the odds for symptomatic improvement was approximately 5.8 times higher in patients of the infarction group compared with the hemorrhage group (OR = 5.787, 95% CI = 2.369-14.134, p = 0. 000). Fifty-one patients (32 with cerebral hemorrhage, 19 with cerebral infarction) received the first local BoNT injection and had available medical records, analysis of which showed a significantly higher rate of symptomatic improvement in patients of the infarction group than those of the hemorrhage group (p = 0.006). After adjustment by factors known to influence treatment outcome (degree of spasticity and paralysis, BoNT dosage, and extent of FDL muscle control of toe movements), the treatment effect was predominantly higher in patients with cerebral infarction.

[CONCLUSION] The BoNT treatment response was better for claw toes in cerebral infarction patients than in hemorrhage patients, possibly suggesting that claw toe is associated with more severe spasticity in this group of patients.