Cerebral Palsy – Medical Aspects (Peds Clin 2008)
· Definition
o Posture/mvmt abnormalities, cause limitations, non-progressive to developing fetal/infant brain.
o Often accompanied by abnormal sensation, cognition, communication, SZ
o Important to explain to family that not the same as muscular dystrophy, not necessarily associated cognitive impairment
· Epidemiology
o 2.5 per 1000 (micropremies now larger proportion)
o Causes (4 P’s)
§ Prematurity / low birth weight (most important risk factor, specific association with spastic diplegia)
§ Prenatal – brain malformation, CVA in utero, CMV infection (also rubella, HSV, toxo)
§ Perinatal – HIE, viral encephalitis, meningitis
§ Postnatal – accidental head trauma, anoxic insult, child abuse
o In most premies, no singular cause is identified (focus on risk factors, find in 40-50%)
§ Also risk with PIH, severe maternal illness, hyperbilirubinemia, hypothermia, hypoglycemia in neonate, multiple gestation, breech
o Wide variation in causes / degree of injury in CP makes harder to do research and apply research findings
o Subtypes
§ Spastic - include hemiplegia, diplegia (lower extremity), quadriplegia
§ Dyskinetic – choreoathetoid, dystonic
§ Hypotonic
§ Mixed
o Gross Motor Functional Classification System – 5 types, stable over time, useful in prognosis
§ I (ambulatory all settings), II (limited in community settings), III (walks with aides), IV (wheelchair or adult assist), V (dependent for mobility)
· Pathogenesis
o May be from insult itself but inflammatory mediators may play a role (maternal illness, chronic lung disease)
o In addition to tone can see weakness, lack of coordination, persistence of primitive reflexes, delayed/absent postural reactions, apraxia, sensory abnormalities
o Motor problems can be 1ary, 2ary or 3ary –
§ 1ary – tone, balance, strength, selectivity problems from CNS injury
§ 2ary – contractures (muscle deformity later leads to bone deformity, especially in the biarticular muscles, deformities from 1ary issues
§ 3ary – adaptive responses to 1ary or 2ary forces
Diagnosis
o Diagnosed clinically
§ Delayed motor milestones, abnormal muscle tone, hyperreflexia, absence of regression or other more specific dx
§ Unlikely to “outgrow” condition – see more “outgrowing” in premies
§ Also may see poor head control, asymmetric fisting, hand preference before 2y/o, lack of postural reactions, persistant primitive reflexes, creep/hop instead of crawl, irritable, poor feed,
§ Many hypotonic initially, spastic show gradual increased tone to 18m, dyskinetic CP show fluctuating tone (hypo/hyper), athetosis after 18-24m, ataxia later
o CP types
§ Spastic (70-80%) – increased resistance to passive motion, UMN syndrome with hyperreflexia, clonus, extensor plantar response, primitive reflex
· Hemiplegia (20% of spastic CP) – one side affected, usually upper extremity more affected than lower extremity. Common to have SZ, visual field defect, astereognosis, proprioceptive loss. Often focal lesion. Walk by 3y/o, independent living prognosis good.
· Diplegia (50% of spastic CP) – lower extremities worse than upper extremities, see scissoring, jump gait, crouch gait, becoming more common from better VLBW survival. Usually normal intelligence, SZ less common. Visual problems common, see PVL. If sit by 2y/o usually walk by 4-7y/o, have hand dexterity / fine motor impairment. Most need surgery for contactures, many use walking aids. Some will develop ataxia at 2-3y/o (cerebellar lesions)
· Quadriplegia (30% of spastic CP) – all four limbs and mouth/pharynx affected, more cerebral dysfunction, worse prognosis. Frequent MR, SZ, visual deficits, oral dysfunction, 15% potential to walk
§ Dyskinetic (10-15%) – athetosis, dystonia, chorea. Usually normal IQ but dysarthria can affect communication skill. Sometimes SN hearing loss. Caused by hyperbilirubinemia, severe anoxia. Most with dystonia unable to walk, some athetosis walk but can be clumsy
o MRI indicated – abnormal in 90% (major/minor brain malformation, in utero CVA, white matter loss, white matter abnormalities – PVL strongly associated with CP in VLBW)
o Consider differential that would treat differently
§ Dystonia responsive to dopamine
§ Metabolic disorder / Inborn error – loss of skills/regression, unusual associated sx (unexplained hypoglycemia, recurrent emesis, progressively worsening SZ). Also consider if FHx of unexplained infant deaths or unexplained neurologic sx
§ Metabolic screening not necessarily indicated in CP in absence of other s/s
§ Mimics – familial spastic paraplegia (FHx), transient toe walking (normal DTRs), muscular dystrophy (calf hypertrophy, Gower), Sjogren-Larrson (icthyosis), Lesch-Nyhan (self mutilation), Mitochondrial (recurrent stroke, cardiomyopathy, hypoglycemia), Miller-Dieker (lissencephally), Rett (acquired microcephally, hand wringing)
· Co-morbidity
o Seizures
§ 30% prevalence in CP (can come at any age, be any type, no specific seizures for CP)
§ Chose anticonvulsant by seizure type and side effect profile, can try off meds if no SZ x 2y (similar to non-CP seizure disorder)
§ Difference in monitoring side effects as they affect CP issues (sedation, appetite)
o Cognition / Learning
§ 50% of CP have associated cognitive impairment (highest risk in quadriplegic, lowest in hemiplegic)
§ Remainder has normal cognitive skill but may have specific deficits that could be classified as learning d/o or ADHD
§ Always exceptions too, give opportunity to demonstrate mental ability, use non-verbal communication if needed
o Nutrition
§ More likely short and underweight – can grow normally and benefit from adequate nutrition
· Look at diet, how long meals take, how child eats – OT may help
· Look at discomfort (constipation,pain), losses (vomit, GERD – may cause early satiety, discomfort after meals,. respiratory sx), medication side effects
§ Can assess growth if complicated by upper arm and tibial length (have standards, need staff training to be accurate)
§ Overweight – can compromise respiratory status, mobility, ease of care
§ Ensure proper Ca, Phos, vit D to prevent osteopenia
o Swallowing problems –
§ Affect aspiration (may be silent, without cough, associated with prolonged feeding time, think of with recurrent wheeze or pneumonia), nutrition
§ Dx gold standard is videofloroscopic study with OT/ST, assess whether do better with thicker or slower feeds
§ May need alternate modes for feeds/hydration if no safe consistency
o Gastrointestinal – GI smooth muscle affected in CP
§ See GERD, constipation, delayed gastric emptying, intestinal dysmotility
§ Can lead to pain, respiratory problems, nutrition, blood loss, dental erosion
§ GERD - treat with acid blockade, pro-motility agents, keep upright after meals, avoid trigger foods and high osmolarity meds/suppliments, treat constipation, surgery
§ G-tube – unable to get sufficient oral nutrition, aspiration risk
· Hard for parents, feeding is parental role, long lasting evidence of child’s disability. May benefit from talking with parent in similar situation
§ Constipation – 80% prevalence in CP, from discomfort, immobility, diet, pelvic or smooth muscle problems, can predispose to UTI
· Tx – help them to sit on toilet, foot support, comfortable positioning, good fiber and fluid intake (too much fiber with too little water will make worse!), medications (beware aspiration with mineral oil!)
o Respiratory
§ Major source of morbidity/mortality especially with severe motor involvement
§ Sleep apnea common, rec sleep study if gasping in sleep, apneic pauses or unexplained day somnolence
§ Aspiration can cause parenchymal lung disease, restrictive disease from obesity and scoliosis
o Vision – retina problems more common in prematurity. CNS problems more cortical vision impairment. Important to identify because often treatable, can affect education and therapy. Should see peds ophtho if problem suspected, some rec baseline eval of all with CP
o Hearing – incidence hearing impairment of 10-15%. Increased risk in premie, HIE, infection. Ex-premie, CMV, ECMO may have late-onset/progressive loss (periodic assessment in first several years of life)
o Pain – common to have musculoskeletal or GI pain, can be hard to diagnose cause (look for time course and association of sx)
o Sleep – report 23% incidence in CP, issues include limit setting, biological clock, discomfort. Some evidence for melatonin as treatment
o Other – watch for voiding dysfunction, dental problems (G-tube fed are at higher risk of carries and gingivitis), drooling (if significant, tx include oromotor therapy, appliances, meds – glycopyrrolate, botox, surgery)
· Prognosis
o Walking – majority of CP walk
§ By subtype – hemiplegic / diplegic – usually walk, quadriplegic – rarely, dyskinetic – intermediate
§ By age of sitting – most who sit independently by 2y/o will walk, unable to sit by 4y/o rarely walk
o Survival – only most severe CP associated with shortened survival
§ Need for tube feeding and inability to lift head in prone – median survival 17y/o
§ More common death from respiratory problem, less from accident/injury
o Transition to adult care
§ Pediatrician can help by: 1) finding adult provider, 2) helping pt & family develop a transition plan, 3) create portable health care summary
§ Templates through National Center of Medical Home Initiatives for Children with Special Needs
· Treatment
o Do not delay treatment pending official diagnosis
o Informing families – families shown to do better when told CP is possibility
o Family centered-care important
§ Medical professionals bring knowledge, training, experience
§ Parents bring specific knowledge about their child and past care received, perspective of child in real-life settings (home, school, community)
§ Open communication and collaboration maximizes adherence, sets the stage for optimal care
o Early Intervention (start before dx established) <3y/o, move to school system at 3y/o.
o Pediatricians help parents with questions about school systems and IDEA, help schools understand how condition and treatment affect child’s school function and education, advocate for therapies, adaptive technologies (may need in different settings)
o Therapies – cornerstone of treatment, few studies use controls or long term f/u
§ PT – posture, mobility, prevent deformity
§ OT – hand skills, adaptive equipment, oromotor/feeding
§ ST – communication (verbal + non-verbal), oromotor/feeding
§ Other – hippotherapy (horses – good esp in diplegia), aquatic exercise (esp good in diplegia), strengthening activities (less well studied)
o Orthotics – increase function, prevent deformity, keep joint functional position, stabilize trunk and extremities, facilitate selective motor control, decrease spasticity
§ Ankle-foot – most common, stability at ankle, put foot in more functional position for gait, could be used to slow development of ankle contractures
§ Knee immobilizer, hip abductor splints used
§ Spinal (attempt to slow progression of scoliosis), Upper extremity (hemiplegia)
§ Night splints to prevent deformity – low compliance
o Aids – transfer aids (lift systems), passive standers, walker, crutches, cane, wheelchair
o Orthopedist – monitor for musculoskeletal complications (contractures, joint dislocations – hip, scoliosis). Surgical interventions used although limited study, some evidence for adductor release in hip subluxation. Can do gait analysis
§ Guidelines – baseline hip films at 30m/o if can walk <10steps, Q6-12m until 7y/o. Spine films at 5 and 10y/o in nonambulatory CP
§ If need surgery, important pre-op to maximize care for GERD, aspiration, nutrition
§ CNS system mature at 4-6y/o, soft tissue surgeries usually 4-7y/o, hand surgery 6-12y/o, bony procedures 8y+ (spastic and hemiplegic are most surgery responsive)
§ After surgery, 3months to regain pre-op strength, up to 1y to see changes in fxn
§ Hemiplegia surgery for pes equines, pes varus, stiff knee, thumb-in palm, wrist flexion deformity
§ Quadriplegia – hip and spinal deformity generally require surgery, scoliosis can happen as early as 5y/o, progressive, hips develop progressive instability, dislocated between 18m-6y/o
o Treatment of abnormal tone
§ Important to distinguish dystonia (involuntary contractions with twisting, repetitive mvmts and abn postures) from spasticity (velocity dependent increase tone)
§ Spasticity – passive stretching, PT. Localized (botox, phenol injection) vs Generalized (baclofen PO or intrathecal pump, dorsal rhizotomy). Be aware that baclofen life-threatening in withdrawal (fever, itch, stiffness) and OD (lethargy, SZ, resp depression)
§ Dystonia – less responsive to treatment, can use trihexyphenidyl. May use IT baclofen (higher dose than spasticity)
o Community agencies (schools, United Cerebral Palsy) – helpful in issues like SSI, respite care, guardianship
o Augmented communication, special technology – helps if motor impairment hinders verbal communication