Differential diagnosis: Comparison of major types of CNS D/oLOCATION OF LESION

CEREBRAL CORTEX CORTICOSPINAL TRACTS

BASAL GANGLIA: SUBCORTICAL GRAY

Disorder Stroke ParkinsonismSensation Impaired or absent: depends on

location of lesion: contralateral sensory loss

Not affected

Tone Hypertonia/spasticity velocity-dependent clasp knife initial flaccidity: cerebral shock

↑ uniform resistance: leadpipe rigidity

Rachet-like at wrist or forearm: cogwheel; independent of rate

Reflexes ↑ hypereflexia Normal or maybe ↓Strength Contralateral weakness/paralysis:

hemiplegiaSlowness of movement

Bulk Normal: acute; disuse atrophy: chronic

Normal or disuse atrophy

Involuntary movements

Spasms Resting tremor

Voluntary movements

Dyssynergic: abnormal timing, coactivation, activation, fatigability

Bradykinesia/akinesia slowness, lack of spontaneous and automatic movements

Postural control

Impaired or absent, depends on the lesion location

Impaired: stooped

Gait Impaired: gait deficits due to abnormal synergies, spasticity, timing deficits

Impaired: shuffling , festinating gait

Spasticity: hypertonic motor d/o characterized by velocity-dependent resistance to passive stretch. Thus the larger and the quicker the sretch, the stronger the resistance of the spastic muscle.clasp knife response: during rapid movement, initial high resistance (spastic catch) may be followed by a sudden inhibition or letting go of the limb (relaxation) in response to a stretch stimulus, termed clasp-knife response.Dyssynergia: impaired ability to associate muscles together for complex movement; decomposition of movementleadpipe rigidity: a hypertonic state characterized by increased uniform resistance that persists throughout the whole ROM & is independent of the velocity of movement. Associated c lesions of the basal ganglia system (extrapyramidal syndromes). Pts demonstare stiffness, inflexibility & significant functional limitationcogwheel rigidity: a hypertonic state of rigidity c superimposed rachet-like jerkiness; characterized by and alternating giving way & then increased resistance to movements (e.g., wrist and elbow flexion & extension). It may represent the presence of tremor superimposed on rigidity.Resting tremor: involuntary oscillatory movements that occur when a body segment is at rest; typically disappears or decreases c purposeful movement.

Bradykinesia: extreme slowness and difficulty maintaining movementAkinesia: inability to initiate or execute movement

Differential diagnosis: comparison of UMN & LMN syndromesUMN lesion LMN lesion

Location of lesion, Structures involved

CNSCortex, brainstem, corticospinal tracts, spinal cord

Cranial nerve nuclei/ nervesSC: anterior horn cells, spinal roots, peripheral nerve

d/o Stroke, TBI, SCI Polio, GBS, PNI, peripheral neuropathy, radiculopathy

Tone Increased: hypertonia, clonusVelocity dependent

Decreased or absent: hypotonia, flaccidityNot velocity dependent

Reflexes Increased: hyperreflexia, clonusExaggerated cutaneous and autonomic reflexes + Babinski

Decreased or absent: hyporeflexiaCuaneous reflexes decreased or absent

Involuntary movements

Muscle spasms: flexor or extensor C denervation: fasciculations

Strength Weakness or paralysis: ipsilateral (stroke) or bilateral (SCI)Corticospinal: contralateral if above decussation in medulla; ipsilateral if belowDistribution: never focal

Ltd distribution: segmental or focal pattern, root-innervated pattern

Muscle bulk Variable, disuse atrophy Neurogenic atrophy; rapid, focal, severe wasting

Voluntary movements

Impaired or absent: dyssynergic patterns, obligatory synergies

Weak or absent if nerve interrupted

Flaccidity/hypotonia: terms used to define decreased or absent muscular tone. Resistance to passive movement is diminished, stretch reflexes are dampened or absent, and limbs are easily moved (floppy) Babinski: dorsiflexion of the great toe c fanning of the other toes on stimulation of the lateral sole of the foot