Neuromuscular blocks with botulinum toxin A and phenol in children with cerebral palsy: preliminary results

Pediatric Neurology – Cerebral Palsy Clinic, “Makarios” Hospital, Nicosia, Cyprus

Spasticity is the predominant muscle dysfunction in Cerebral Palsy (CP). Muscle blocks with Botulinum toxin A (BtA) and motor nerve blocks with phenol have been used in the management of spasticity in adults and recently in a limited number of children with CP. Increasing evidence shows that neuromuscular blocks may temporarily reduce spasticity and therefore prevent fixed deformitities, and delay orthopaedic surgery especially in young children.

The aim of this present study is:

1) To assess the efficacy of (a) BtA muscle blocks and (b) phenol neural blocks on reducing spasticity in dysfunctioning muscles of the lower and upper extremities in DP children,
2) To evaluate possible side effects of the afents used.

Materials and Methods:

Ten CP children with ages ranging from 3 to 15 years (median 4,5) were selected for intervention. Four non ambulant children had quadriplegia. Six ambulatory patients had hemiplegia 3, diplegia 2, and triplegia 1. botulinum toxin A (Dysport, UK) was injected i.m. in all patients in the gastrocnemius, tibialis posterior and upper extremity musxles as indicated. Total dose was calculated at a max of 30 IU/kg BW/patient and distruted to individual muscles according to their size and degree of spasticity. Phenol 5% in normal neurostimultor. The proximal motor points of hip adductors and hamstrings of the four most spastic quadriplegic patients (who hadexceeded max BtA doses) were injected. All children had a complete assessment in the immediate pre-treatment period and were followed up to the end of second month post-injections, until the preparation of this abstract. Each child serves as its own control. Evaluations included a neurological, orthopaedic and physical therapy examination and videorecordings. The degree of spasticity was estimated by Ashworth scale. The range of motion to passive movement (PROM) was measured with a manual goniometer. The Gross Motor Function Measure test (GMFM) was used for functional assessment.

Results:

All children tolerated well the procedures. Mild side effects were reported by two BtA patients (transient pain and lower extremities weakness). One phenol patient complained of dysesthesias and pain at the site of injection which lasted over 2 weeks. All but one patient had an improvement, as reported by parents and physiotherapists, by the end of the 1st post-treatment month. The post-injection Ashworth scores were lower in all patients, especially after the 2nd week, but failed to reach statistical significance. Degrees of PROM measurements showed a significant improvement (p<05) in all patients. The more marker changes were noted in the hip adductors of four quadriplegic patients treated with phenol (p<01). Total GMFM scores were higher in all children, two months after treatment. Functional sitting scores were significantly improved (p<05) in the non ambulant patients.

Conclusions:

This preliminary study in children with CP provides some evidence that BtA injections in appropriately selected muscles of lower and upper extremities have no major side effects and may reduce spasticity, significantly increase passive range of motion in the involved joints and positively influence motor functional scores in ambulatory patients. Phenol motor neurolysis is well tolerated only under general anaesthesia and is a more elaborate and invasive technique with potential side effects. It may be selectively applied to severely spastic large muscle groups of non ambulatory patents when BtA max dosage has been exceeded. In these cases it may provide significant amelloration in the range of motion of hip adductors, resulting in significantly better sitting and positioning.