Objectives: To assess the efficacy of botulinum toxin injections for hypertonic upper limbs in patients with residual motricity that allows a functional use of the hand.
Methods: Patients were seen between February 2000 and November 2002, before and after botulinum toxin injections for hypertonic upper limbs due to upper motor neuron syndrome. All patients had voluntary motricity in fingers and wrist extensors. Impairment (range of motion, spasticity [Ashworth's scale]), pain (10 centimeters visual analog scale) prehension (400-point measure) and patients' satisfaction were recorded. Two or three functional goals were predefined. Patients were injected after locating the target area with neurostimulation. The aim of the injections was functional improvement.
Results: Eight patients were included. After injections, mean pain score decreased by 3.4 points; mean spasticity decreased by 1.0; and prehension improved, especially for bimanual functions. Three-quarters of the functional goals were reached. Optimal efficacy required repeated injections, with modification of muscle targets and doses.
Conclusion: Botulinum toxin injection is efficient for impairment, pain and prehension in hypertonic upper limbs, even if the hypertonic hand is still the "nondominant" hand. Motricity in antagonist muscles is essential for functional improvement, and the assessment must include bimanual tasks. Intrinsic as well as extrinsic muscles must be injected and a neurostimulator used for forearm muscles. Comparative studies are required to define more clearly the place of this treatment among medical and surgical treatments of spasticity.