MOTOR SYSTEM Dr. Zahoor Ali Shaikh. TRANSVERS SECTION OF SPINAL CORD

download MOTOR SYSTEM Dr. Zahoor Ali Shaikh. TRANSVERS SECTION OF SPINAL CORD

of 29

  • date post

    31-Mar-2015
  • Category

    Documents

  • view

    225
  • download

    7

Embed Size (px)

Transcript of MOTOR SYSTEM Dr. Zahoor Ali Shaikh. TRANSVERS SECTION OF SPINAL CORD

  • Slide 1

MOTOR SYSTEM Dr. Zahoor Ali Shaikh Slide 2 TRANSVERS SECTION OF SPINAL CORD Slide 3 MOTOR UNIT Slide 4 Types of motor neuron motor neuron - motor neuron Slide 5 Types of muscle fibers Extrafusal muscle fibers ( cause muscle contraction supplied by - motor neuron) Intrafusal muscle fibers or muscle spindle (receptor for stretch reflex, supplied by - motor neuron) Slide 6 MUSCLE SPINDLE (INTRAFUSAL FIBERS) Slide 7 MUSCLE EXTRAFUSAL FIBERS MUSCLE INTRAFUSAL FIBERS Slide 8 Muscle spindle Nuclear bag fiber Nuclear chain fiber Sensory innervations of muscle spindle Ia nuclear bag & nuclear chain fibers II nuclear chain fibers Motor supply motor neuron Dynamic & Static Slide 9 Reflex Definition Components of reflex arc Receptor Afferent pathway Center Efferent pathway Effector organ Slide 10 Components of reflex arc Slide 11 Classification of reflexes Monosynaptic or stretch reflex or tendon jerk eg. Bicep jerk tricep jerk, supinator jerk knee jerk, ankle jerk Polysynaptic reflex eg. Withdrawal reflex Abdominal reflex Plantar reflex Visceral reflex eg. Micturation, defecation reflex Jendressik Phenomenon Slide 12 KNEE JERK MONOSYNAPTIC REFLEX Slide 13 Slide 14 Slide 15 POLYSYNAPTIC REFLEX Slide 16 WITDRAWEL REFLEX - POLYSYNAPTIC REFLEX Slide 17 DIFFERENT REFLEXES SHOWN Slide 18 Slide 19 Slide 20 Slide 21 Slide 22 Motor cortex corticospinal (pyramidal tract) Upper motor neuron (pyramidal & extrapyramidal tracts) Lower motor neuron Difference between upper & lower motor neuron lesion (UMNL & LMNL) Slide 23 Slide 24 Slide 25 Slide 26 MOTOR TRACTS Slide 27 Slide 28 DIFFERENCE BETWEEN UPPER & LOWER MOTOR NEURON LESION UMN LESION Paralysis affect movement rather than muscles Muscle wasting is only from disuse, therefore slight. Occasionally marked in chronic severe lesions. Spasticity of clasp- knife type. Muscles hypertonic. LMN LESION Individual muscle or group of muscles are affected. Wasting pronounced. Flaccidity. Muscles hypotonic. Slide 29 Tendon reflexes increased. Clonus often present. Superficial reflexes diminished or modified. Abdominal reflex absent. Babinskis sign +ve, Increased jaw jerk. Tendon reflexes diminished or absent. Superficial reflexes often unaltered.