Pediatric Hypertonia: What’s New? OACRS 2005 Darcy Lynn Fehlings, MD, MSc, FRCP(C) Irene Koo, BSc, PT

Objectives Clinical Pathways for Decision Making with Botulinum Toxin To highlight new clinical developments in: 1) Botulinum Toxin (BTA): hip subluxation, upper extremity dosing 2) Treatment of Dystonia 3) Prevention of Contractures

Hypertonia Management: Use of Clinical Pathways for Decision Making Irene Koo, BSc, PT OACRS October 4, 2005

Objectives Review use of GMFCS levels in Botox ® Clinic Review use of Outcome Measures Review Clinical Pathways in Botox ® Clinic

Indicators for Botox ® Change in function Growth Pain Hip migration Hip subluxation Caregiving issues Contracture (?)

GMFCS levels Gross Motor Function Classification System for Cerebral Palsy for details, download GMFCS levels from CanChild website: www. fhs.mcmaster.ca/canchild Palisano et. al. (1997)

Spastic Equinus Indicators GMFCS Levels IIIIIIIVV Heel Rounding X XX Gast/Sol Contracture X X X Difficulty with AFO tolerance X X X

Clinical Indicators GMFCS Levels IIIIIIIVV Hip Crouch XXX Knee Crouch XXX Scissor/ Narrow BOS XXX Gait Deviations

Clinical Indicators GMFCS Levels IIIIIIIVV Decreased toe clearance XXX Decreased sitting XX Increased Clonus XXXXX Functional Changes

Clinical Indicators GMFCS Levels IIIIIIIVV Rocker Bottom Feet XXXX Midfoot Break XXXXX Anatomical Changes

Indicators GMFCS Levels IIIIIIIVV Hip Pain XXX Hip Subluxation XXX Hip Dislocation XX Hips at Risk

Outcomes Used Tardieu and Modified Ashworth Scale Selective Motor Control Scale Physician Rated Observational Gait Scale GMFM Goal Attainment Scaling

Clinic Ax: Tardieu Scale Muscle ROM *norms *R1*R2 Hip adductors45-30 to 1030 Hamstrings< to 7050 to 40 Soleus30-30 to –200-5 Gastrocnemius20-30 to * figures in degrees +IGT guided injection

Clinic Ax: Modified Ashworth Scale MAS of 0 or 1: children have no or very minimal tone and generally would not benefit from Botox ® MAS of 4: children have fixed contracture deformity, Botox ® generally not indicated MAS 1+, 2 or 3 more likely to become Botox ® candidates

Clinical Pathways: from Botox ® Clinic to P.T. treatment

Randomized Trial of BTA combined with hip bracing… Boyd et al. DMCN 2004, 46: 9 Randomized trial of 90 children with spastic CP to Tx of BTA q 6 monthly into adductors and hamstrings and SWASH brace 8 hours per day or control group (monitoring) over 3 year period Control Group progressed faster to hip surgery (X- ray: MP > 40% or AI> 27% lead to surgical referral)

Prevention of Hip Disolocation with BTA Marek et al.. DMCN 2005: 47, 12 RCT of 67 children with spastic CP to Tx group of BTA q3 monthly to iliopsoas, adductors, hamstrings or control group (observation) Results: Mean Progression of MP was –1 0% in tx group and +3% in control group (p< )

A Randomized Controlled Trial Comparing Low Dose and High Dose BTA in the Upper Extremity of Children with Hypertonia: A. Kawamura, MD, FRCP(C) K. Campbell, PhD D. Fehlings, MD, MSc, FRCP(C)

Conclusions Low dose as effective as a high dose in improving hand function Hypothesis that lower dose would be more effective was not proven No differences in grip strength or side effect profile

Dosing Guideline Recommendations Biceps: 1U/kg Brachioradialis: 0.75U/kg Finger/Wrist Flexors: 1.5U/kg Pronator teres: 0.75U/kg Thumb adductor: 0.3U/kg (max 10U) Thumb opponens: 0.3U/kg (max 10U)

Oral Pharmacotherapy: Trihexyphenidyl (Artane) Can be useful in children with dystonia Suppresses an overactivity of central cholinergic effects in dystonia Dosage: start at a low dosage and work up every two weeks (0.5 mg bid - work up to tid and increase until effect noted) - can get up to doses of 40 mg Side Effects: constipation, urinary retention

Chocolate Trial (Childhood Hypertonia of central origin: an open- label trial of anticholinergic treatment effects) Sanger et al.. DMCN 2005:47, 17 Primary Objective: to see if Artane improved UE function 23 children with dystonia in dominant UE, GMFCS II-IV Small improvements measured on the Melbourne at 14 weeks, no impact on QL, “Hyperkinetic” Group deteriorated Adverse effects: chorea, hyperactivity

Prevention of Severe Contractures might replace multi-level surgery in CP…. Hagglund et al.. JofPedOrtho 2005, 14: In 1994 in Sweden a CP register and health care program to prevent hip dislocation and contractures was initiated Health Care Program: standardized follow-up 2x per year (CP sub-type, GMFCS, PROM, GM function, X-ray of hips) In 1992 – ITB, in 1993 – SDR, 1998 – BTA Also serial casting, orthoses, and PT Children analyzed at 8 years of age

Results 209 children in the study Tables demonstrate “good PROM’ at many levels (eg in GMFCS I-III 153 of 157 children could dorsiflex to neutral) Decrease in Orthopedic Surgery and procedures became “single-level”

Conclusion “ With new techniques to reduce spasticity paired with a population-based screening program it seems possible to prevent the development of severe contractures in children with CP, reducing the need for multi-level orthopedic procedures.”

References 1.Bottos, M et. al. (2003). Botulinum toxin with and without casting in ambulant children with spastic diplegia: a clinical and functional assessment. Dev Med Child Neurol. 45: Boyd, R.N., et. al. (2001). The effect of botulinum toxin type A and variable hip abduction orthosis on gross motor function: a randomized control trial. European Journal of Neurology. 8(Suppl.5): Kay, R.M., et. al. (2004). Botulinum toxin as an adjunct to serial casting treatment in children with cerebral palsy. J. Bone and Joint Surgery. 86:11: Koman, L.A., et. al. (2000). Botulinum toxin type A Neuromuscular blockade in the treatment of lower extremity spasticity in cerebral palsy: a randomized, double-blind, placebo controlled trial. J of Pediatr Orthop. 20:1: Palisano, R. et. al. (1997). Gross motor classification system for cerebral palsy. Dev Med Child Neurol. 39: Pidcock, F.S. et. al. (2005). Hip migration percentage in children with cerebral palsy treated with botulinum toxin type A. Arch Phys Med Rehabil. 86: Plazek, R. et. al. (2004). Treatment of lateralization and subluxation of the hip in cerebral palsy with Botulinum Toxin A: Preliminary results based on the analysis of migration percentage data. Neuropediatrics. 35: 6-9.