OR9.1 | Cerebral Palsy Orthopaedic Assessment — Summary & Reflection

KEY TAKEAWAYS

Cerebral palsy is a group of non-progressive brain disorders producing permanent movement impairment, classified by motor type (spastic ~75%, dyskinetic, ataxic), topographic distribution (hemiplegia, diplegia, quadriplegia), and functional level (GMFCS I–V). The aetiology reflects the spectrum of perinatal brain injury: periventricular leukomalacia (prematurity — spastic diplegia), HIE (term asphyxia — spastic quadriplegia or dyskinesia), and haemorrhage/infection. The hallmark UMN signs — increased spastic tone, hyperreflexia, Babinski sign, minimal wasting — directly contrast with the LMN picture of PPRP (flaccid, absent reflexes, wasting). The central management challenge is the spasticity spiral: spasticity → dynamic deformity → fixed contracture → bony deformity. Management is multidisciplinary and time-sensitive: physiotherapy and orthotics throughout; botulinum toxin A for dynamic spasticity; selective dorsal rhizotomy for appropriately selected diplegic GMFCS II–III children aged 4–7; single-event multilevel surgery for fixed deformities in ambulatory children; intrathecal baclofen for severe non-ambulatory CP. Hip surveillance using Reimers migration percentage is mandatory — intervene at >25% to prevent dislocation. In surgery, the key distinction from PPRP is that CP requires tendon LENGTHENING (overactive spastic muscle) not tendon transfer (a paralysed muscle has no donor to substitute).

REFLECT

Reflect on the following: Two 8-year-old boys each present with equinus foot and a scissor gait. Boy A has a history of premature birth at 28 weeks; he has brisk reflexes, an extensor plantar response, minimal limb wasting, and normal sensation. Boy B has a history of fever and paralysis at age 2; he has absent reflexes, a flexor plantar response, obvious limb wasting, and normal sensation. How do you explain to each family why the same visible deformity has a completely different underlying cause, a different treatment approach, and a different long-term prognosis? What are the key investigations and referrals you would arrange for each? Reflect on how misdiagnosing one condition as the other would lead to inappropriate and potentially harmful management.