Deep Tendon ReflexesKimberly Victorian, RN, BSN

Sheeba Jacob, RN, BSN

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

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

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

GradingGrading based on varied degree of

responseGrade 0 Absent Grade 1+decreased but still presentGrade 2+normal or physiologicGrade 3+ increased and may be

normalGrade 4+ hyperactive with transient sustained clonusGrade 5+ hyperactive with sustained clonus

Clonus Definition :Clonus is the alternate involuntary

muscular contraction and relaxation in rapid Succession

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

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

Physical Maturity Infants Children Adults

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

Disease Processes Absent reflex causes:

– Peripheral neuropathy – Alcoholism– Vitamin deficiencies– Diabetes

Clonus or Hyper-active reflexes

Upper motor neuron lesion

http://www.youtube.com/watch?v=WGNCXqa-y3ohttp://www.youtube.com/watch?v=lT9XhORYHJ8&feature=related

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

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

Answer 1 C.

DTR Test True or False

A hypo-tonic deep tendon reflex is indicated by an absent or diminished response to tapping

Answer True

DTR Test True or False

There are 5 grades of Deep tendon reflexes

Answer 3 True

DTR test What portion of the examination is

most important to keep in mind?A. The maturity of the patientB. Assure patient is relaxedC. Mental cognition of the patient

Answer 4 B.

DTR Test Identify which of the following is not

a DTRA. Ankle jerkB. Jaw jerkC. Finger jerkD. Ear skip

Answer 5 D.

DTR Test True or False

Diabetes is associated with absent or hypo-tonic DTRs

Answer 6 True

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