[Post stroke hemiplegia: interest of botulinum toxin injection at the upper limb]

Efficacy of botulinum toxin A for the treatment of hemiparesis in adults with chronic upper limb spasticity

Introduction

this study aimed to evaluate the effectiveness of botulinum toxin A (BoNT-A) injection in hemiparetic patients with chronic spasticity in the upper limb resulting from stroke or traumatic brain injury.

Methods

we conducted a retrospective study including 45 patients seen, in our department of Physical Medicine and Rehabilitation, between January 2014 and December 2016. All patients received an injection of BoNT-A (Dysport, 100 U/ml). Affected upper-extremity muscles could be injected as per the investigator’s discretion to a maximum total dose of 1000 U. We evaluated muscle tone using Modified Ashworth Scale (MAS). Functional disability was assessed using Modified Frenchay Scale (MFS), Nine Hole Peg Test (NHPT) and Barthel Index (BI). Quality of life (QoL) was assessed using the 36-Item Short Form Health Survey (SF-36). The achievement of treatment goal was assessed by the Goal Attainment Scaling (GAS).

Results

patients decreased their MAS score over the first and the third months (p<0.05). MFS showed improvement at 1 month after injection with a median change from baseline of 8 (range: 1-16; p<0.001). The change from baseline ranged from 0 to 5 points for NHPT at 1 month after injection (p< 0.001). This functional improvement was maintained to 3 months. Improvements in Barthel Index was observed at 3 months with a median change from baseline of 5 points (range 0-15; p<0.001). The mean change from baseline of SF-36 score was 4.77 ± 3.39 (p<0.001). The mean GAS T-score was 47.04 ±7.78 (median 50, IQR 7.7), giving a mean (SD) change from baseline of 25.36 ± 8.46 (95% CI 22.82 to 27.90; p <0.001). Binary logistic regression was used to identify the independent factors predicting a favorable functional outcome of Bon-T treatment. It showed that neglect was independent predictive factor treatment failure (p=0.009, OR=3.2) while previous injection of BoNT-A was an independent predictive factors of treatment success (p=0.009, OR=0.3).

Conclusion

our study showed a good response to BoNT-A injection delivered in the management of chronic upper limb spasticity resulting from stroke or traumatic brain injury. It demonstrated its outcome in improving muscle tone, function and QoL. It also showed that the majority of patients achieved their goal as defined at the start of the treatment, mainly for patients who received previous injection of BoNT-A.

Membres supérieurs fonctionnels hypertoniques et toxine botulique. Quels résultats fonctionnels ?

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.