Deep Tendon Reflexes

1. Deep Tendon Reflexes Kimberly Victorian, RN, BSN Sheeba Jacob, RN, BSN

2. Objectives • Understand and define Deep Tendon Reflexes • Distinguish between hyper and hypo-tonic Deep Tendon Reflexes • Gain a basic knowledge of Deep Tendon Reflex grading • Understand how to do a Deep Tendon Reflex examination • Identify different Deep Tendon Reflexes • Identify different diseases that may manifest by an alteration in Deep Tendon Reflexes

3. Definition Normal process when muscle tendon is tapped briskly Muscle contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle Afferent neuron innervates the muscle or golgi tendon organ associated with the muscles Cerebral cortex and some brainstem nuclei exert influence over the sensory input of muscle spindles

4. Hyper VS Hypo-reflexia Hypo – absent or diminished response to tapping. Disease involving one or more of the components of the two-neuron Hyper – hyperactive or repeating (clonic) reflexes. Diseases involving an interuption of corticospinal and other descending pathways that influence the reflex arc due to a suprasegmental lesion

5. Grading Grading based on varied degree of response • Grade 0 Absent • Grade 1+decreased but still present • Grade 2+normal or physiologic • Grade 3+ increased and may be normal • Grade 4+ hyperactive with transient sustained clonus • Grade 5+ hyperactive with sustained clonus

6. Clonus Definition : Clonus is the alternate involuntary muscular contraction and relaxation in rapid Succession

7. Examination Examine upper extremity reflexes with upper examination Abnormality found or suspected take into account the entire group with focus on the technique of the examination Assure patient is relaxed

8. Method of Eliciting Reflexes • Assure that the patient is RELAXED • Knee reflex for example: • would include having patient seated, then have the patient cross their legs after which, the examiner can hold the hammer with the mallet at the bottom, and then lets it swing into the patellar tendon

9. Physical Maturity Infants Children Adults

10. Examples of Reflexes Jaw Jerk Biceps reflex Triceps reflex Brachioradialis reflex Finger jerk Knee Jerk Ankle jerk

11. Disease Processes • Absent reflex causes: • Peripheral neuropathy • Alcoholism • Vitamin deficiencies • Diabetes

12. Clonus or Hyper-active reflexes Upper motor neuron lesion http://www.youtube.com/watch?v=WGNCXqa-y3o http://www.youtube.com/watch?v=lT9XhORYHJ8&feature=related

13. Summary Definition Hypo VS Hyper-active reflexes Grading Examination Examples Diseases

14. DTR Test • Of the following, what best defines a deep tendon reflex • A. a specific bundle of nerve fibers • B. an unintended muscle spasm • C. a normal process that occurs when the tendon is tapped

15. Answer 1 • C.

16. DTR Test • True or False A hypo-tonic deep tendon reflex is indicated by an absent or diminished response to tapping

17. Answer • True

18. DTR Test • True or False There are 5 grades of Deep tendon reflexes

19. Answer 3 • True

20. DTR test • What portion of the examination is most important to keep in mind? A. The maturity of the patient B. Assure patient is relaxed C. Mental cognition of the patient

21. Answer 4 • B.

22. DTR Test • Identify which of the following is not a DTR A. Ankle jerk B. Jaw jerk C. Finger jerk D. Ear skip

23. Answer 5 • D.

24. DTR Test • True or False Diabetes is associated with absent or hypo-tonic DTRs

25. Answer 6 • True

26. Resources Walker, K . (1990). Clinical Methods, The History, Physical, and Laboratory Examinations. Retrieved October 20, 2009 from www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=cm&part=A2361