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Lecture Notes

Assessment of the Reflexes

  1. purposes
    1. to determine changes in the internal environment of the body
    2. to yield valuable information on general health status
    3. to provide information needed to identify specific systemic diseases
    4. to determine the health status of a defense mechanism of the nervous system
  2. structure and function
    1. function
      1. a defense mechanism of the nervous system
    2. structure
      1. the reflex arc is:
        1. a involuntary stereotypical response
        2. simplest unit of sensory and motor function
        3. operates below the level of conscious control
        4. permits a quick reaction to potentially painful or damaging situations
        5. has five components:
          1. an intact sensory nerve (afferent)
          2. a functional synapse in the spinal cord
          3. an intact motor nerve fiber (efferent)
          4. the neuromuscular junction
          5. a competent muscle
      1. to elecit a reflex arc:
        1. the afferent (sensory) limb of the reflex arc is stimulated
        2. the stimulated afferent (sensory) limb of the reflex arc conducts afferent (sensory) impulses through the dorsal root of the spinal nerve to the spinal cord
        3. the afferent (sensory) impulses synapse in the gray matter of the spinal cord with the efferent (motor) limb of the reflex arc
        4. the stimulated efferent (motor) impulses conducts efferent (motor) impulses out the ventral root of the spinal nerve to the neuromuscular junction
        5. the efferent (motor) impulses simtulate the release of neurotransmitters at neuromuscular junction
        6. the release of neurotransmitters at the stimulated neuromuscular junction causes a brisk contraction of the muscle
      2. methods to reinforce DTRs
        1. for upper extremitiy DTRs
          1. have the patient clench teeth or push down on the bed with his/her thighs at the same time of testing
        1. for lower extremity DTRs
          1. have the patient lock fingers and try to pull them apart at the same time of testing (Jendrassik's maneuver)
      3. segmental levels of the DTRs
        1. Achilles (ankle) reflex
          1. sacral 1 primarily
        2. patellar (knee) reflex
          1. lumbar 2, 3, 4
        3. supinator (brachioradialis) reflex
          1. cervical 5, 6
        4. biceps reflex
          1. cervical 5, 6
        5. triceps reflex
          1. cervical 6, 7
        6. adominal reflexes
          1. upper
            1. thoracic 8, 9, 10
          2. lower
            1. thoracic 10, 11, 12
        7. plantar (Babinski)
          1. lumbar 5, sacral 1
  3. pertinent history
    1. adult
      1. headache
      2. head injury
      3. dizziness/lightheadedness
      4. vertigo
      5. seizures
      6. tremors or other involuntary movements
      7. paresis or paralysis
      8. coordination problems
      9. paresthesias
      10. difficulty swallowing
      11. difficulty speaking
      12. significant past history of neurological disease
      13. medications
      14. use of alcohol
      15. drug abuse
      16. exposure to environment/occupational hazards
      17. self-care behaviors
      18. usual state of health
  4. preparation of the patient and environment
    1. patient
      1. greet the patient and establish rapport
      2. explain the procedure to the patient in simple terms what will be done, what he/she should expect, and how he/she can cooperate during the examination
      3. provide for privacy
      4. assist the patient in assuming a position of sitting up straight with his/her legs dangling over an examining table and then lying supine on an examining table with his/her head on a small pillow
      5. expose any body part(s) of the patient that need to be exposed and drape any body part(s) of the patient that do not need to be exposed during the examination
      6. encourage the patient to ask questions and mention any discomfort he/she feels during the examination
    2. environment
      1. private
      2. adequately lit
      3. warm
      4. quiet
  5. techniques of examination
    1. test the biceps reflex
      1. test the biceps reflex, by:
        1. standing on the right side of the patient
        2. instructing the patient to relax his/her right arm on his/her right thigh with his/her forearm midway between flexion and extension
        3. placing the thumb of your left hand firmly on the biceps tendon of the patient's right arm
        4. holding the triangular reflex hammer between the thumb and index finger of your right hand
        5. striking the thumb of your left hand with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
        6. standing on the left side of the patient
        7. instructing the patient to relax his/her left arm on his/her left thigh with his/her forearm midway between flexion and extension
        8. placing the thumb of your right hand firmly on the biceps tendon of the patient's left arm
        9. holding the triangular reflex hammer between the thumb and index finger of your left hand
        10. striking the thumb of your right hand with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
      2. normal findings:
        1. average; normal (2+)
          1. average, normal flexion at the elbow and contraction of the biceps muscle
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal flexion (hypoactive) at the elbow and contraction of the biceps muscle
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal flexion at the elbow and contraction of the biceps muscle
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum flexion (hyperactive) at the elbow and contraction of the biceps muscle
    2. test the triceps reflex
      1. tests the triceps reflex, by:
        1. standing on the right side of the patient
        2. instructing the patient to flex his/her right arm at the elbow with the palm facing toward his/her chest
        3. pulling the patient's right arm slightly across his/her chest with your left hand
        4. holding the triangular reflex hammer between the thumb and index finger of your right hand
        5. striking the patient's triceps tendon above the insertion of the ulna's olecranon process about 1 - 2 inches above the elbow with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
        6. standing on the left side of the patient
        7. instructing the patient to flex his/her left arm at the elbow with the palm facing toward his/her chest
        8. pulling the patient's left arm slightly across his/her chest with your right hand
        9. holding the triangular reflex hammer between the thumb and index finger of your left hand
        10. striking the patient's triceps tendon above the insertion of the ulna's olecranon process about 1 - 2 inches above the elbow with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
      2. normal findings:
        1. average; normal (2+)
          1. average, normal extension at the elbow and contraction of the triceps muscle
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal extension (hypoactive) at the elbow and contraction of the triceps muscle
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal extension at the elbow and contraction of the triceps muscle
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum extension (hyperactive) at the elbow and contraction of the triceps muscle
    3. test the supinator or brachioradialis reflex
      1. test the supinator or brachioradialis reflex, by:
        1. standing on the right side of the patient
        2. instructing the patient to relax his/her right arm on his/her right thigh with his/her forearm partly pronated
        3. holding the triangular reflex hammer between the thumb and index finger of your right hand
        4. striking the styloid process of the patient's radius about 1 - 2 inches above the wrist with the wide end of the triangular reflex hammer by swinging it at the wrist, not the elbow
        5. standing on the left side of the patient
        6. instructing the patient to relax his/her left arm on his/her left thigh with his/her forearm partly pronated
        7. holding the triangular reflex hammer between the thumb and index finger of your left hand
        8. striking the styloid process of the patient's radius about 1 - 2 inches above the wrist with the wide end of the triangular reflex hammer by swinging it at the wrist, not the elbow
      2. normal findings:
        1. average; normal (2+)
          1. average, normal supination of the forearm
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal supination (hypoactive) of the forearm
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal supination of the forearm
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum supination (hyperactive) of the forearm
    4. test the patellar (knee) reflex
      1. test the patellar (knee) reflex, by:
        1. standing on the right side of the patient
        2. placing your left hand on the quadriceps muscle of the patient's right leg
        3. holding the triangular reflex hammer between the thumb and index finger of your right hand
        4. striking the patient's right patellar tendon just below his/her right patella with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
        5. standing on the left side of the patient
        6. placing your right hand on the quadriceps muscle of the patient's left leg
        7. holding the triangular reflex hammer between the thumb and index finger of your left hand
        8. striking the patient's left patellar tendon just below his/her left patella with the pointed end of the triangular reflex hammer by swinging it at the wrist, not the elbow
      2. normal findings:
        1. average; normal (2+)
          1. average, normal extension at the knee and contraction of the quadriceps muscle
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal extension (hypoactive) at the knee and contraction of the quadriceps muscle
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal extension at the knee and contraction of the quadriceps muscle
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum extension (hyperactive) at the knee and contraction of the quadriceps muscle
    5. test the Achilles (anke) reflex
      1. test the Achilles (ankle) reflex, by:
        1. standing on the right side of the patient
        2. holding the triangular reflex hammer between the thumb and index finger of your right hand
        3. slightly dorsiflexing the patient's right ankle with your left hand
        4. striking the patient's Achilles tendon just above its insertion site on the posterior aspect of the calcaneous with the wide end of the triangular reflex hammer by swinging it at the wrist, not the elbow
        5. standing on the left side of the patient
        6. holding the triangular reflex hammer between the thumb and index finger of the left hand
        7. slightly dorsiflexing the patient's left ankle with your right hand
        8. striking the patient's Achilles tendon just above its insertion site on the posterior aspect of the calcaneous with the wide end of the triangular reflex hammer by swinging it at the wrist, not the elbow
      2. normal findings:
        1. average; normal (2+)
          1. average, normal plantar flexion at the ankle
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal plantar flexion (hypoactive) at the ankle
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal plantar flexion at the ankle
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum plantar flexion (hyperactive) at the ankle
    6. test the abdominal reflex
      1. test the abdominal reflex, by:
        1. gathering a sterile cotton-tipped applicator
        2. standing on the right side of the patient
        3. briskly stroking the upper right side (below the ribcage and above the umbilicus) of the patient's abdomen horizontally laterally to medially toward the umbilicus with the wooden end of the sterile cotton-tipped applicator
        4. briskly stroking the upper left side (below the ribcage and above the umbilcus) of the patient patient's abdomen horizontally laterally to medially toward the umbilicus with the wooden end of the the sterile cotton-tipped applicator
        5. briskly stroking the lower right side (below the umbilicus and above the symphysis pubis) of the patient's abdomen horizontally laterally to medially toward the umbilicus with the wooden end of the sterile cotton-tipped applicator
        6. briskly stroking the lower left side ((below the umbilicus and above the symphysis pubis) of the patient's abdomen horizontally laterally to medially toward the umbilicus with the wooden end of the sterile cotton-tipped applicator
      2. normal findings:
        1. average; normal (2+)
          1. average, normal contraction of the abdominal muscles and deviation of the umbilicus toward midline
      3. deviations from normal findings:
        1. absent (0)
          1. no response
        2. somewhat diminished; low normal (1+)
          1. minimal contraction of the abdominal muscles (hypoactive) and deviation of the umbilicus toward midline
        3. brisker than average; possibly but not necessarily indicative of disease (3+)
          1. more active than normal contraction of the abdominal muscles and deviation of the umbilicus toward midline
        4. very brisk; hyperactive, with clonus (4+)
          1. maximum contraction of the abdominal muscles (hyperactive) and contraction of the umbilicus toward midline
    7. test the cremasteric reflex (in males)
      1. test the cremasteric reflex (in males). by:
        1. standing on the right side of the patient
        2. lightly stroking the inner aspect of the patient's right thigh, moving proximally to distally, with the wooden end of the sterile cotton-tipped applicator
        3. lightly stroking the inner aspect of the patient's left thigh, moving proximally to distally, with the wooden end of the sterile cotton-tipped applicator
      2. normal findings:
        1. elevation of the testicle
      3. deviations from normal findings:
        1. absence of elevation of the testicle
    8. test the plantar (Babinski) reflex
      1. test the plantar (Babinski) reflex, by:
        1. standing on the right side of the patient
        2. stroking the lateral aspect of the sole of the patient's right foot from the heel to the ball, curving medially across the heads of the metatarsal bones, with the wooden end of the sterile cotton-tipped applicator
        3. stroking the lateral aspect of the sole of the patient's left foot from the heel to the ball, curving medially across the heads of the metatarsal bones, with the wooden end of the sterile cotton-tipped applicator
      2. normal findings:
        1. plantar flexion of all the toes
      3. deviations from normal findings:
        1. dorsiflexion of the great toe and fanning out of all the toes (+ Babinski)
    9. test for ankle clonus
      1. test for ankle clonus, by:
        1. standing on the right side of the patient
        2. supporting the patient's right knee with your left hand in a partly flexed position
        3. briskly dorsiflexing the patient's right ankle with your right hand
        4. maintaining the patient's right ankle in dorsiflexion with your right hand
        5. supporting the patient's left knee with your left hand in a partly flexed position
        6. briskly dorsiflexing the patient's left ankle with your right hand
        7. maintaining the patient's left ankle in dorsiflexion with your left hand
      2. normal findings:
        1. absence of rhythmic oscillations between dorsiflexion and plantar flexion when the ankle stays in dorsiflexion
      3. deviations from normal findings:
        1. presence of rhythmic oscillations between dorsiflexion and plantar flexion when the ankle stays in dorsiflexion

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This page was last modified on 1/1/02