Signs and Symptoms

Early identification of children who have CP allows for early therapeutic intervention and screening for asso­ciated conditions. Because CP is a descriptive term that does not infer a single etiology, pathology, or progno­sis, there is no specific diagnostic test.

The first step in the evaluation for suspected CP is a comprehensive history, including a detailed account of potential risk factors and family history. A thorough history of developmental milestones is also important. Often the parent's initial concern is a significant delay in attaining motor milestones. Prematurity must be considered when evaluating development because milestones are generally corrected for the degree of prematurity. A discrepancy between motor and cog­nitive milestones should always raise suspicion for CP. Certain deviations in developmental milestones are associated with CP. For example, early hand pref­erence or asymmetric use of the extremities may be the first indication of hemiparesis. Early head control, rolling, or rigid standing are all associated with abnor­mally increased tone and/or exaggerated primitive reflexes. The parent may also describe unusual means of mobility, such as bunny hopping, combat crawling, or bottom scooting. The most important aspect of the developmental history is to confirm that the child has not lost any skills or milestones, as this would suggest a neurodegenerative disorder.

Following a detailed history, a thorough physical examination should be performed. A careful neurologic exam is an essential piece of the evaluation. In infancy, the neurologic exam focuses on tone and infantile developmental reflexes. Deep tendon reflexes, plantar responses, and the presence of clonus are more infor­mative in the older child. Tone should be assessed by gently moving the infant's joints through their appro­priate range of motion and evaluating the amount of resistance. Careful observation will also provide infor­mation about an infant's tone. Infants with severe hypotonia will lay in a frog-leg position with their hips abducted, flexed, and externally rotated. Their arms will lie limply at their sides. Persistent fisting or scissoring may be observed with increased tone. Most infants will undergo an early stage of mild or moderate hypotonia prior to more traditional signs of CP. A prolonged period of hypotonia or fluctuating tone is more typical of dys- kinetic CP. In general, however, longer periods of hypo­tonia and severe hypotonia are associated with more severe motor deficits, regardless of the type of CP.

The earliest indication of CP may be a delay in the disappearance of primitive infantile reflexes. Commonly examined primitive reflexes include the Moro reflex, palmar grasp reflex, asymmetric tonic neck reflex, and tonic labyrinthine reflex. During the first six months of life, maturation of the cortex grad­ually overrides these primitive responses, and vol­untary motor activity should increase. Persistence of these primitive reflexes past six months of age, asym­metry of the response, or an obligatory response at any age should be considered highly suspicious for a sig­nificant motor impairment. As the primitive reflexes become suppressed, postural or protective reactions such as the parachute and the equilibrium or tilting reactions should emerge. In children with CP, pos­tural reactions may be less effective, appear later than usual, or fail to develop.

A definitive diagnosis of CP should be made cau­tiously, especially in the first six months of life. Infants who are suspected of having CP should be followed closely with serial developmental evaluations and physical exams until the diagnosis is clear. Further evaluation, including neuroimaging, should be con­sidered to help clarify the diagnosis.