What techniques do you use to elicit deep tendon reflexes?
With the patient sitting, place one hand underneath the sole and dorsiflex the foot slightly. Then tap on the Achilles tendon just above its insertion on the calcaneus. If the patient is in bed, flex the knee and invert or evert the foot somewhat, cradling the foot and lower leg in your arm. Then tap on the tendon.
Does hypothyroidism affect deep tendon reflexes?
Delayed relaxation of deep tendon reflexes (Woltman sign)1 is seen in about 75% of patients with hypothyroidism and has a positive predictive value of 92% in overtly hypothyroid patients. In unaffected patients, the relaxation time for deep tendon reflexes is 240–320 ms.
What does the Jendrassik maneuver do?
The Jendrassik maneuver is a medical maneuver wherein the patient clenches the teeth, flexes both sets of fingers into a hook-like form, and interlocks those sets of fingers together. The tendon below the patient’s knee is then hit with a reflex hammer to elicit the patellar reflex.
Where do you hit deep tendon reflexes?
The brachioradialis reflex is observed by striking the brachioradialis tendon directly with the hammer when the patient’s arm is resting. Strike the tendon roughly 3 inches above the wrist….Deep Tendon Reflexes.
| Rate the reflex with the following scale: | |
|---|---|
| 3+ | Brisker or more reflexive than normally. |
| 2+ | Normal |
| 1+ | Low normal, diminished |
Why does hypothyroidism cause delayed deep tendon reflexes?
… Delayed relaxation of deep tendon reflexes is due to impaired calcium sequestration by sarcoplasmic reticulum, which prolongs twitch duration. [3] Deep tendon reflexes are delayed in approximately 85% of patients with hypothyroidism.
What is delayed deep tendon reflexes?
Woltman’s sign (also called Woltman’s sign of hypothyroidism or, in older references, myxedema reflex) is a delayed relaxation phase of an elicited deep tendon reflex, usually tested in the Achilles tendon of the patient.
What does absent deep tendon reflexes mean?
Deep tendon reflexes may be absent when either the afferent volley is unable to access the spinal cord (sensory polyneuropathy, the spinocerebellar degenerations, root avulsion) or when the resulting efferent volley is unable to access the muscle (motor neuronopathy, radiculopathy, and certain neuromuscular junction …
What is the response when the patellar tendon is tapped with a hammer?
Striking of the patellar tendon with a reflex hammer just below the patella stretches the muscle spindle in the quadriceps muscle. This produces a signal which travels back to the spinal cord and synapses (without interneurons) at the level of L3 or L4 in the spinal cord, completely independent of higher centres.
How to get a response from a deep tendon reflex?
If you cannot get any response with a specific reflex—ankle jerks are usually the most difficult—then try the following: Several different positions of the limb. Get the patient to put slight tension on the muscle being tested. One method of achieving this is to have the patient strongly contract a muscle not being tested.
What causes a muscle to move in a deep reflex?
The aroused receptors initiate the reflex arc, causing the muscle to move. Deep reflexes include patellar, Achilles, plantar, triceps, and biceps reflexes. With superficial reflexes, light stroking on the skin stimulates the cutaneous tissue, which initiates the reflex arc and causes the underlying muscle to twitch.
What kind of reflexes do you feel when you tap your hand?
Observe three potential reflexes as you tap. Brachioradialis reflex: flexion and supination of the forearm. Biceps reflex: flexion of the forearm. You will feel the biceps tendon contract if the biceps reflex is stimulated by the tap on the brachioradialis tendon. Finger jerk: flexion of the fingers.
How long does it take for the reflex arc to occur?
Undeniably, the reflex arc, which causes contraction, takes place in a few milliseconds. Simply put, one side of the reflex arc detects a stretch in the muscle, whereas the other side of the reflex arc causes the muscle to twitch ( Spinal motor structures. ). FIGURE 1 Reflex Arc.