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 dosing2) 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

I II III IV V

Heel Rounding

  

X   X X

Gast/SolContracture

 

X

 

X X

Difficulty with AFO

tolerance

 

X

 

X  X

ClinicalIndicators

GMFCS Levels

I II III IV V

Hip Crouch

  X X X  

Knee Crouch

  X X X  

Scissor/Narrow BOS

  X X X 

Gait Deviations

ClinicalIndicators

GMFCS Levels

I II III IV V

Decreased toe clearance

X X X   

Decreased sitting

    X X 

Increased Clonus

X X X X X 

Functional Changes

ClinicalIndicators

GMFCS Levels

I II III IV V

Rocker Bottom Feet   X X X X

Midfoot Break

X X X X X

 

Anatomical Changes

IndicatorsGMFCS Levels

I II III IV V

Hip Pain     X X X

Hip Subluxation

   

X X X

Hip Dislocation

   

  X X

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 ScaleMuscle ROM *norms *R1 *R2

Hip adductors 45 -30 to 10 30

Hamstrings < 20 160 to 70 50 to 40

Soleus 30 -30 to –20 0-5

Gastrocnemius 20 -30 to -10 0-5

* 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

R e a sse ss o u tco m esF /U in c lin ic

P icke d up fo r u p to 1 2 se ssio nsw ith in 3 m o f in je c tion

N e w C lie n t

R e a sse ss o u tco m es F /U in c lin ic

P icke d up fo r u p to 6 se ss io nsw ith in 3 m o f in je c tion

R e pe a t B o to x®

G M F C S L e ve l I

R e a sse ss o u tco m esF /U in c lin ic

P icke d up fo r u p to 1 2 se ssio nsw ith in 3 m o f in je c tion

G M FC S L e ve l I I a n d L e ve l I II

R e a sse ss O u tco m es

P icke d up fo r u p to 6 se ss io nsw ith in 3 m o f in je c tion

G M F C S L e ve l IV

C o nsu lta tion

G M F C S L e ve l V

O u tco m e M e asu resA d m in is te red

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<0.00001)

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: 269-273

• 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.”

References1. 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: 758-762.

2. 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): 109-119.

3. 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. 86:11:2377-2384.

4. 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: 108-115.

5. Palisano, R. et. al. (1997). Gross motor classification system for cerebral palsy. Dev Med Child Neurol. 39: 214-223.

6. 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: 431-435.

7. 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.