Ahmad Alghadir M.S. Ph.D. P.T. RHS 332: Clinical Neurology Ahmad Alghadir, M.S. Ph.D. P.T. Room: 2071

Ahmad Alghadir M.S. Ph.D. P.T. Recommended texts S.B. O’sullivan, T.J. Schmitz, Physical Rehabilitation: Assessment and Treatment, F.A. Davis Company. 3 rd ed R.L. Braddom, Physical Medicine & Rehabilitation, W.B. Saunders Company. 1 st ed

Ahmad Alghadir M.S. Ph.D. P.T. Motor Control Assessment

Ahmad Alghadir M.S. Ph.D. P.T. II. Tone Definition: “resistance of muscle to passive elongation or stretch.” ---Tonal abnormalities--- a)Hypertonia: “state of increased tone above normal resting levels.” (spasticity and rigidity) b)Hypotonia: “state of decreased tone below normal resting levels.” (flaccidity) c)Dystonia: “impaired or distorted tonicity.”

Ahmad Alghadir M.S. Ph.D. P.T. Spasticity Definition: velocity-dependent increase in tone or resistance of muscle to passive stretch causing stiff movements with exaggerated tendon jerks. Quicker stretch  stronger resistance.

Ahmad Alghadir M.S. Ph.D. P.T. Characteristics of spasticity: 1.Clasp-knife reflex: an initial high resistance followed by a sudden relaxation or letting go of a spastic muscle in response to a stretch reflex. 2.Clonus: cyclic hyperactivity of antagonistic muscles occurring at a regular frequency in response to sustained stretch to a spastic muscle.

Ahmad Alghadir M.S. Ph.D. P.T. Brainstem lesions: (see figure 7-4). 1.Decerebrate: sustained contraction (spasticity) of extensor muscles in the upper and lower limbs as a result of a brainstem lesion between the red nucleus and vestibular nuclei (subthalamus to midpons).

Ahmad Alghadir M.S. Ph.D. P.T. 2.Decorticate: sustained contraction (spasticity) of extensors in the lower limbs and flexors in the upper limbs as a result of a brainstem lesion above the red nucleus.

Ahmad Alghadir M.S. Ph.D. P.T. Rigidity Definition: stiffness or inability to bend or be bent. “In rigidity, resistance is uniformly increased in both agonist and antagonist muscles, rendering body parts stiff and immoveable.” “Independent of the velocity of a stretch stimulus.” Parkinson’s disease.

Ahmad Alghadir M.S. Ph.D. P.T. Characteristics of rigidity: 1.Cogwheel rigidity: “ratchetlike response to passive movement characterized by an alternate letting go and increasing resistance to movement.” 2.Leadpipe rigidity: “constant resistance to movement.”

Ahmad Alghadir M.S. Ph.D. P.T. Flaccidity Definition: “absence of muscle tone.” LMNL. Spinal or cerebral shock (temporary state  hypertonic state). Hypersensitivity and hyperextensibility.

Ahmad Alghadir M.S. Ph.D. P.T. Dystonia Definition: “hyperkinetic movement disorder characterized by impaired or disordered tone, and sustained and twisting involuntary movements.” Inherited (idiopathic), neurodegenerative disorders (basal ganglia).

Ahmad Alghadir M.S. Ph.D. P.T. Characteristics of dystonia: 1.“Muscle contractions may be slow or rapid, and are repetitive and patterned.” 2.“Tone fluctuate in an unpredictable manner from low to high.”

Ahmad Alghadir M.S. Ph.D. P.T. ---Tonal assessment--- Factors affecting tone: position, stress, anxiety, volitional effort, medications, temperature, level of arousal and alertness, bladder state, fever, and infection.

Ahmad Alghadir M.S. Ph.D. P.T. 1.Initial observation: Abnormal posturing (abnormal synergies)  spasticity or rigidity. Complete absence of spontaneous movements  flaccidity. Involuntary movements  dystonia.

Ahmad Alghadir M.S. Ph.D. P.T. 2.PROM: Varying the speed of movement  spasticity (clasp-knife reflex). Sudden stretch  spasticity (clonus). Side to side comparison in cases of localized or unilateral dysfunction.

Ahmad Alghadir M.S. Ph.D. P.T. General scale to evaluate tone: 0 – no response (flaccidity). 1 – decreased response (hypotonia). 2 – normal response. 3 – exaggerated response (mild to moderate hypertonia). 4 – sustained response (severe hypertonia).

Ahmad Alghadir M.S. Ph.D. P.T. Modified Ashworth scale to evaluate spasticity: (see table 8-2).

Ahmad Alghadir M.S. Ph.D. P.T. Pendulum test: normal and hypotonic limb swings for several oscillations, hypertonic limb resists swinging. Drop arm test: normal limb falls momentarily then catches and maintains the position, hypotonic limb falls abruptly, hypertonic limb demonstrates delay and resistance to falling.

Ahmad Alghadir M.S. Ph.D. P.T. III. Muscle strength See table 8-5.

Ahmad Alghadir M.S. Ph.D. P.T. IV. Reflexes 1.Superficial cutaneous reflexes: (see table 8-3). 2.Deep tendon reflexes: (see table 8-1).

Ahmad Alghadir M.S. Ph.D. P.T. V. Balance Definition: “stability produced on each side of a vertical axis.” “The center of mass (COM) is maintained over the base of support (BOS).” Goals of balance control system: safety and function.

Ahmad Alghadir M.S. Ph.D. P.T. Components of balance control system: 1.Sensory elements. 2.Sensory interaction. 3.Musculoskeletal elements.

Ahmad Alghadir M.S. Ph.D. P.T. 1. Sensory elements a) Visual system: - Function: “Detects the relative orientation of the body parts and the orientation of the body with reference to the environment.” (visual proprioception) “Relays information about the organization of the external environment.” Visually guided movements.

Ahmad Alghadir M.S. Ph.D. P.T. - Assessment: Visual acuity: Snellen eye chart. Bitemporal hemianopsia: optic chiasm lesion.

Ahmad Alghadir M.S. Ph.D. P.T. b) Somatosensory inputs: - Components: Cutaneous sensations (touch and pressure) from body parts in contact with the support surface. Joint and muscle proprioceptors.

Ahmad Alghadir M.S. Ph.D. P.T. - Function: “Detect the relative orientation and movement of body parts and orientation of the support surface.” - Assessment: Sensory examination of trunk and extremities. Foot and ankle are critical in assessing somatosensory contribution to balance.

Ahmad Alghadir M.S. Ph.D. P.T. c) Vestibular system: - Function: “Detects angular and linear acceleration and deceleration forces acting on the head.” Detects the orientation of the head with reference to gravity. Stabilizes gaze during head movements (vestibulo-ocular reflex).

Ahmad Alghadir M.S. Ph.D. P.T. - Assessment: Barany test: nystagmus  vestibular system lesion. “Nystagmus: rhythmic, oscillatory movement of the eyes.”

Ahmad Alghadir M.S. Ph.D. P.T. 2. Sensory interaction All sensory inputs contribute to the sense of equilibrium. Sense of equilibrium: “sense of the position of the COM in relation to the support surface.”

Ahmad Alghadir M.S. Ph.D. P.T. “Because these inputs are redundant, stable balance can be maintained in the absence of vision, on unstable surfaces, or in sensory conflict situations.” “If more than one sensory system is deficient however, lack of balance control will be evident.”

Ahmad Alghadir M.S. Ph.D. P.T. Stable support surface, normal vision  somatosensory inputs. Stable support surface, absent vision  somatosensory inputs. Disturbed support surface, normal vision  visual system. Disturbed support surface, absent vision  vestibular system

Ahmad Alghadir M.S. Ph.D. P.T. Assessment: - Clinical Test for Sensory Interaction in Balance (CTSIB): (see figure 8-2). * “Each condition is maintained for 30 seconds.” * Scoring: “Changes in the amount and direction of postural sway” (1=minimal, 2=mild, 3=moderate, 4=fall).

Ahmad Alghadir M.S. Ph.D. P.T. Time in balance (stopwatch, 30s). * Nausea and dizziness. - Dynamic posturography (e.g. balance master).

Ahmad Alghadir M.S. Ph.D. P.T. 3. Musculoskeletal elements Limits of stability (LOS): “maximum angle from vertical that can be tolerated without a loss of balance.” Nashner: LOS=12° in anteroposterior direction, LOS=16° in medial-lateral direction.

Ahmad Alghadir M.S. Ph.D. P.T. Musculoskeletal responses to disturbance of COM to preserve balance: a)Monosynaptic reflexes. b)Postural synergies (functional reflexes). c)Equilibrium reactions. “As the LOS are reached with a COM disturbance, the magnitude of the postural response increases.”

Ahmad Alghadir M.S. Ph.D. P.T. b) Postural synergies 1.Ankle strategy: “Involves shifting the COM forward and back by rotating the body as a relatively rigid mass about the ankle joints.” Muscle activation pattern: distal to proximal. Utilized with small disturbances of COM within LOS.

Ahmad Alghadir M.S. Ph.D. P.T. 2.Hip strategy: “Involves shifts in the COM by flexing or extending at the hips.” Muscle activation pattern: proximal to distal. Utilized with larger disturbances of COM within LOS.

Ahmad Alghadir M.S. Ph.D. P.T. 3.Stepping strategy: “Realigns the BOS under the COM by using rapid steps in the direction of the displacing force.” “Elicited when the limits of stability are reached in response to fast, large postural perturbations.” Utilized when “ankle or hip strategies are no longer sufficient to maintain balance.”

Ahmad Alghadir M.S. Ph.D. P.T. “Postural synergies can function in either a feedback mode (as a reaction to a specific stimulus) or in a feedforward mode (in preparation for voluntary movement which requires a balance adjustment).”

Ahmad Alghadir M.S. Ph.D. P.T. c) Equilibrium reactions “Total compensatory reaction involving automatic movements of the limbs and trunk.” Initial response elicits postural synergies. As LOS are reached, compensatory trunk, arm, and head movements are added.

Ahmad Alghadir M.S. Ph.D. P.T. Factors influencing postural synergies and equilibrium reactions: 1.Previous experiences. 2.Currently available sensory inputs. 3.Specific parameters of the disturbing stimulus. 4.Body position at the time of imbalance.

Ahmad Alghadir M.S. Ph.D. P.T. Assessment of musculoskeletal elements: 1.ROM, tone, and strength. 2.Responses to perturbation. 3.Assessment of static balance (maintenance of posture). 4.Assessment of dynamic balance (balance during weight shifting or movement).

Ahmad Alghadir M.S. Ph.D. P.T. 2. Responses to perturbation Postural stress test: -”Measure of motor responses to specified weight disturbances during standing.” -”Weights (equal to 1.5%, 3%, and 4% of body weight) are applied through a pulley system to a waist belt which is, in turn, attached to the patient.” Expected and unexpected perturbations.

Ahmad Alghadir M.S. Ph.D. P.T. Strategies and reactions might be: a)Present and normal. b)Present but limited. c)Present but inappropriate for the particular situation. d)Abnormal. e)Absent.

Ahmad Alghadir M.S. Ph.D. P.T. 3. Assessment of static balance a)Double limb support. b)Single limb support. c)Tandem (heel-toe position).

Ahmad Alghadir M.S. Ph.D. P.T. 4. Assessment of dynamic balance a)Standing up. b)Walking. c)Turning. d)Stopping. e)Starting.

Ahmad Alghadir M.S. Ph.D. P.T. Scoring: 1.Simple three-point scale: absent, impaired, and present. 2.Functional balance grades: see table Time in balance (stopwatch, 30s).

Ahmad Alghadir M.S. Ph.D. P.T. Dynamic posturography. Force platform.

Ahmad Alghadir M.S. Ph.D. P.T. Factors influencing motor control assessment Cognition. Perception. Arousal. Communication. Sensation.