# Cerebral Palsy: Classification and Rehabilitation Management

## Overview
Most common motor disability in childhood (prevalence: 2-3 per 1,000 live births). Group of permanent disorders of movement and posture caused by non-progressive disturbances in the developing fetal or infant brain. Motor impairment often accompanied by: epilepsy (25-45%), intellectual disability (30-50%), visual impairment (40%), hearing loss (10%), communication disorders, behavioral issues. NOT a progressive condition, but functional manifestations change with growth and aging. Lifelong condition requiring physiatric management from childhood through adulthood.

## Etiology
**Prenatal (80%)**: brain malformations, intrauterine infections (TORCH), maternal conditions, genetic factors, periventricular leukomalacia from placental insufficiency. **Perinatal (10%)**: birth asphyxia, prematurity, intracranial hemorrhage (especially IVH Grade III-IV in preterm infants). **Postnatal (10%)**: meningitis, encephalitis, traumatic brain injury, near-drowning, kernicterus.

## Classification Systems

### Topographic Classification
**Hemiplegia/hemiparesis**: one side affected (arm usually more than leg). **Diplegia/diparesis**: both lower extremities primarily affected (common in premature infants with PVL). **Quadriplegia/quadriparesis**: all four extremities affected (most severe motor involvement). **Monoplegia**: single limb (rare, often evolves into hemiplegia). **Triplegia**: three limbs (relatively rare designation).

### Motor Type Classification
**Spastic (70-80%)**: velocity-dependent increase in muscle tone, hyperreflexia, clonus. UMN pattern: corticospinal tract involvement. Most common type. **Dyskinetic (10-15%)**: 
Dystonic: sustained, twisting postures, co-contraction. Choreoathetoid: involuntary, writhing movements. Basal ganglia involvement (often from kernicterus or asphyxia). **Ataxic (5-10%)**: cerebellar involvement.

Impaired coordination, balance, intention tremor. Wide-based gait, dysmetria. **Mixed**: combination of types (commonly spastic + dyskinetic).

### Gross Motor Function Classification System (GMFCS)
5-level classification based on self-initiated movement with emphasis on sitting, walking, and wheeled mobility. Age-dependent descriptions (0-2, 2-4, 4-6, 6-12, 12-18 years). **Level I**: walks without limitations; limitations in advanced motor skills (running, jumping). **Level II**: walks with limitations; difficulty with uneven surfaces, stairs without railing, long distances.

**Level III**: walks using hand-held mobility device (walker, crutches); may use wheelchair for long distances. **Level IV**: self-mobility with limitations; transported in manual wheelchair or uses power wheelchair. **Level V**: transported in manual wheelchair in all settings; severe limitations in head/trunk control. GMFCS level by age 2 is predictive of adult ambulatory status. Stable over time (does not improve with intervention).

| GMFCS Level | Mobility | Assistive Devices | Ambulatory Prognosis |
|-------------|----------|-------------------|---------------------|
| I | Walks without limitations | None | Community ambulator |
| II | Walks with limitations | Railing for stairs | Community ambulator with difficulty |
| III | Walks with hand-held device | Walker, crutches | Household/limited community |
| IV | Limited self-mobility | Power wheelchair | Primarily wheelchair |
| V | Transported in all settings | Manual wheelchair (pushed) | Non-ambulatory |

<image>GMFCS levels I through V with illustrations showing functional mobility at each level</image>

### Other Classification Systems
**Manual Ability Classification System (MACS)**: hand function, 5 levels. **Communication Function Classification System (CFCS)**: communication ability, 5 levels. **Eating and Drinking Ability Classification System (EDACS)**: feeding, 5 levels.

## Comprehensive Assessment

### Motor Function Assessment
Gross Motor Function Measure (GMFM-66 or GMFM-88): standardized measure of gross motor abilities. GMFM-66 motor growth curves: predict functional ceiling by GMFCS level. GMFCS I-II: peak motor function at age 5-7. GMFCS III: peak at age 4-5.

GMFCS IV-V: peak at age 3-4. Functional plateau or decline can occur in adolescence/adulthood. Gait analysis (instrumented): guides surgical decision-making. Functional mobility assessment in home and community environments.

### Musculoskeletal Assessment
Range of motion: monitor for progressive contractures. Common contractures: hip flexion, knee flexion, ankle equinus, wrist flexion. Hip surveillance: regular radiographic monitoring for hip displacement. Migration percentage (Reimers index): percentage of femoral head uncovered.

GMFCS IV-V: highest risk for hip displacement (60-90%). Surveillance schedule: every 6 months for GMFCS III-V until skeletal maturity. Scoliosis screening: especially GMFCS IV-V. Limb length discrepancy assessment.

### Associated Conditions
Epilepsy management and seizure control. Visual assessment (cortical visual impairment, strabismus). Hearing screening. Cognitive and learning assessment.

Behavioral and psychiatric screening. Pain assessment (often underrecognized - up to 75% of children with CP experience pain). Nutritional status and growth (failure to thrive, obesity). Drooling assessment and management. Constipation.

## Spasticity Management

### Non-Pharmacologic
Stretching and positioning programs. Serial casting (progressive stretch into range). Orthotic management (AFOs, hand splints). Weight-bearing programs. Hippotherapy, aquatic therapy.

### Pharmacologic - Oral Medications
**Baclofen (oral)**: GABA-B agonist, sedation and tolerance limit efficacy. **Diazepam**: GABA-A agonist, sedation and dependence concerns. **Tizanidine**: alpha-2 agonist, less sedation than diazepam. **Dantrolene**: direct muscle relaxant, hepatotoxicity risk (monitor LFTs). Oral medications generally more useful for generalized spasticity.

### Botulinum Toxin Injections
Focal spasticity management. OnabotulinumtoxinA or abobotulinumtoxinA. Common targets: gastrocnemius-soleus (equinus), hamstrings, hip adductors, biceps, pronator teres. Onset: 3-7 days; Duration: 3-6 months.

Combined with stretching, casting, orthotics, and therapy for optimal results. Dosing: 10-20 units/kg total body dose (onabotulinumtoxinA). Guidance: EMG, electrical stimulation, or ultrasound for accurate muscle localization.

### Intrathecal Baclofen (ITB) Therapy
Programmable pump delivers baclofen directly to intrathecal space. 100-1000x less dose than oral (minimizes systemic side effects). Indications: generalized spasticity GMFCS III-V, failed oral medications. Trial via lumbar puncture before permanent implant.

Complications: catheter malfunction, infection, baclofen withdrawal (life-threatening - fever, seizures, rhabdomyolysis). Requires lifelong management and regular pump refills.

### Selective Dorsal Rhizotomy (SDR)
Surgical sectioning of selected dorsal (sensory) nerve rootlets (L1-S2). Permanent reduction in spasticity. Best candidates: GMFCS II-III, spastic diplegia, good selective motor control, adequate strength. Requires intensive post-operative rehabilitation (12-18 months). Long-term outcomes: improved gait quality, reduced need for orthopedic surgery.

<image>Spasticity management options in cerebral palsy showing escalating interventions from conservative to surgical</image>

## Orthotic Management
**AFOs (ankle-foot orthoses)**: most commonly prescribed. Solid AFO: maximum control, prevents equinus and crouch. Hinged AFO: allows dorsiflexion, prevents plantarflexion (free or adjustable). Ground reaction AFO: prevents crouch gait (knee extension moment).

Posterior leaf spring (PLS): flexible, assists toe clearance in swing. **KAFOs**: for significant knee instability or extensor weakness. **Upper extremity orthoses**: wrist cock-up splints, thumb abduction splints, neoprene thumb wraps. **Spinal orthoses**: for scoliosis management (limited evidence for preventing progression in neuromuscular scoliosis).

## Orthopedic Surgery
Goal: correct musculoskeletal deformities to improve function and prevent deterioration. **Single-event multilevel surgery (SEMLS)**: correcting multiple deformities in one surgical procedure. Reduces total number of surgeries and rehabilitation episodes. Requires instrumented gait analysis for planning.

Common procedures: Gastrocnemius/Achilles lengthening (equinus). Hamstring lengthening (crouch gait). Adductor release/transfer (scissoring, hip at risk).

Femoral derotation osteotomy (internal rotation gait). Hip reconstruction (subluxation/dislocation). Scoliosis fusion (neuromuscular scoliosis GMFCS IV-V).

## Transition to Adult Care
Planning should begin at age 14-16. Address: vocational planning, independent living skills, sexuality/reproductive health, transportation, financial/legal considerations (guardianship). Adult physiatrist should assume ongoing management. Functional decline in adulthood: pain, fatigue, decreasing mobility common by 30s-40s.

Chronic musculoskeletal overuse: shoulder pain from wheelchair use, cervical myelopathy in dyskinesia. Ongoing need for spasticity management, orthotic prescription, equipment maintenance. Mental health screening: depression and anxiety rates increased in adults with CP.

## Clinical Pearls
GMFCS level at age 2 predicts lifelong ambulatory potential - GMFCS I-III will walk, GMFCS IV-V will use wheelchairs as primary mobility. Hip surveillance with regular radiographs is essential for GMFCS III-V children - hip displacement is preventable with early detection and intervention. GMFM-66 motor growth curves show that most children with CP reach their peak motor function by age 5-7, followed by plateau or decline - set realistic expectations with families. Botulinum toxin injections without concurrent therapy, stretching, and orthotics will fail - the injection creates a window of opportunity that must be leveraged with rehabilitation. Pain is present in up to 75% of children with CP but is frequently underrecognized and undertreated - always ask about pain and use appropriate assessment tools for nonverbal patients.

<image>Hip surveillance protocol for cerebral palsy showing migration percentage measurement and intervention thresholds by GMFCS level</image>

## References
- Rosenbaum P, et al. A report: the definition and classification of cerebral palsy April 2006. Dev Med Child Neurol Suppl. 2007;109:8-14.
- Palisano R, et al. Development and reliability of a system to classify gross motor function in children with cerebral palsy. Dev Med Child Neurol. 1997;39(4):214-223.
- Novak I, et al. A systematic review of interventions for children with cerebral palsy: state of the evidence. Dev Med Child Neurol. 2013;55(10):885-910.
- Hanna SE, et al. Stability and decline in gross motor function among children and youth with cerebral palsy. Dev Med Child Neurol. 2009;51(4):295-302.
- Graham HK, et al. Cerebral palsy. Nat Rev Dis Primers. 2016;2:15082.