What is the difference between deep tendon reflexes and superficial reflexes?

Deep tendon reflexes (DTRs) result from stimulation of stretch-sensitive nerve fibers in neuromuscular spindles, causing muscle contraction graded 0-4. Superficial reflexes are segmental responses from specific sensory inputs like the blink or abdominal reflex, graded as present or absent. DTRs help localize neurologic disorders, while superficial reflexes assess different neural pathways.

How does a Babinski sign differ from a normal plantar reflex response?

A normal adult plantar reflex produces plantar flexion of the big toe when the sole is stroked. A Babinski sign occurs with pyramidal tract damage, causing the big toe to extend upward and other toes to fan outward. This abnormal response resembles the normal infant response and indicates upper motor neuron dysfunction.

What does dysdiadochokinesia indicate during coordination testing?

Dysdiadochokinesia is the inability to perform smooth, rapid alternating movements due to cerebellar disease. During testing, patients may show irregular rhythm, jerky motions, or difficulty coordinating hand or foot movements. This finding helps clinicians identify cerebellar dysfunction and localize neurologic lesions affecting coordination centers.

What does a positive Romberg sign reveal about a patient's neurologic status?

A positive Romberg sign occurs when a patient maintains balance with eyes open but exhibits instability, excessive sway, or falls with eyes closed. This indicates a proprioception disorder affecting sensory feedback pathways. The test helps distinguish between cerebellar dysfunction and sensory nerve damage.

How do hemiparetic gait and diplegic gait differ in presentation?

Hemiparetic gait results from unilateral weakness and spasticity, causing the affected limb to remain stiffly extended and drag around the body in a circumducting pattern. Diplegic gait affects both sides with a scissoring adductor pattern in both legs. Both reflect upper motor neuron involvement but differ in laterality and movement pattern.

Why is heel and toe walking useful in motor assessment?

Heel and toe walking tests specific ankle movements and strength. Walking on toes assesses plantar flexion, while walking on heels evaluates dorsiflexion strength at the ankles. These tests help screen for weakness, particularly foot drop caused by muscle or nerve damage affecting ankle motor function.

What does the finger-to-nose test assess in coordination evaluation?

The finger-to-nose test evaluates point-to-point coordination by having patients touch the examiner's finger, then their own nose, repeatedly and at increasing speed. The examiner assesses accuracy, rapidity, and smoothness while observing for dysmetria (side-to-side movements) or intention tremor, signs of cerebellar disease.

Motor Exam II

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1. Reflexes testing.

The proper use of the reflex hammer and the relaxation of the patient and muscle to be tested are critical in eliciting DTRs. The reflex hammer should be held loosely in the hand and guided by the thumb and index finger. The swing should be in an arc-like fashion, making use of the angular momentum, keeping the wrist loose and striking the tendon briskly. Close attention to the position of the limb is important to ensure the muscle is in a relaxed position. Clearly identify the tendon of the muscle to be tested. It can be helpful to make conversation with the patient to promote relaxation. Observe the muscle for contraction, and look for limb movement. If despite following all these procedures a DTR is not elicited, try the other side. If again a DTR is not elicited, then try the Jendrassik maneuver (described in the next section).

Upper Extremity Reflexes
1. Biceps Reflex
  1. Have the patient relax the arm, and pronate the forearm midway between flexion and extension. Palpate the biceps tendon in the antecubital fossa, and place one finger on the tendon. Use the reflex hammer to tap your finger using proper technique.
  2. Observe for biceps muscle contraction. The elbow may flex slightly or the muscle may simply contract without other observable movement.
2. Brachioradial Reflex
  1. Have the patient place the forearm in semiflexion and semipronation. Ensure that the patient's forearm is resting on the patient's lap in a seated position (on the patient's abdomen if lying down) to ensure full relaxation.
  2. Place your finger on the tendon (1-2 inches above the wrist) and use the broad area of the reflex hammer to tap. Observe for flexion at the elbow and supination at the wrist.
3. Triceps Reflex
  1. Have the patient flex the forearm at the elbow midway between flexion and extension, and pull the arm toward the chest. Tap the triceps tendon 2 inches above the elbow. Observe for contraction of the triceps muscle and extension at the elbow.
  2. Another maneuver is to hang the patient's arm over your arm, and make sure the patient is placing the full weight of the arm on yours. Tap the triceps tendon in this position, and again observe for contraction of the triceps muscle and extension of the elbow.
Lower Extremity Reflexes
1. Patellar Reflex
  1. If the patient is sitting, with the legs dangling off the side of the bed or examination table, place your hand on the patient's quadriceps muscle and strike the patellar tendon firmly. Feel for contraction of the quadriceps, and extension at the knee should be observed.
  2. If the patient is lying supine in bed, place the arm under the knee so that the knee is flexed to slightly less than 90°, and strike the knee below the patella. Watch the quadriceps for contraction and the knee for extension.
2. Achilles Reflex (Ankle jerk)
  1. If the patient is sitting, place a hand under the patient's foot to partially dorsiflex the ankle. With the wide end of the reflex hammer, tap the Achilles tendon just above its insertion on the posterior aspect of the calcaneus. Note contraction of the calf muscles and plantar flexion at the ankle.
  2. If the patient is lying down, hold foot in a partially dorsiflexed position with a medial malleolus facing the ceiling. The knee should be flexed and lying to the side. Strike the Achilles tendon directly. Watch the muscles of the calf for contraction, and feel for plantar flexion of the foot.
  3. Assess for clonus at the ankle. Dorsiflex the ankle briskly, and maintain the foot in that position. Note the clonus, which is rhythmic muscle contraction. More than 3 beats of clonus or any asymmetry between feet is abnormal.
Plantar Reflex
1. Gently stroke the bottom of the foot, starting laterally and near the heel, and moving up and across the ball of the foot (metatarsal heads). If no response, increase your pressure. A normal response is the great toe moving downward.
  If there is a disorder of the pyramidal tract or upper motor neuron (or in infants), the great toe will extend and the other toes will fan out. This pathological response of toe dorsiflexion is referred to as the Babinski sign.
Reinforcement of reflexes (Jendrassik maneuver)
1. If a reflex is unobtainable, perform a reinforcement (Jendrassik) maneuver by having the patient perform isometric contraction of other muscles, which increases the response of deep tendon reflexes.
2. To increase responses in upper extremities, ask the patient to clench the teeth as you swing the hammer.
3. To reinforce responses in lower extremities, ask the patient to link the hands across the chest, and pull one against the other as you swing the hammer.

2. Coordination and Gait Testing

Rapid Alternating Movements
1. Ask the patient to slap the palm of the hand on the thigh, then turn it over and strike the back of the hand on the thigh. Demonstrate the task, and ask the patient to do it with one hand and then to do it faster. Assess for rhythmicity, and then ask the patient to repeat it on the other side.
2. Ask the patient to tap the tip of the index finger against the distal joint of the thumb, and demonstrate the task to the patient.
  1. Have the patient repeat the movement on one side and then the other side. Compare how smoothly the task is done, and assess the speed and rhythm.
    Patients are often a bit slower performing these tasks on the non-dominant side. Inability to perform smooth rapid alternating movements due to cerebellar disease is called dysdiadochokinesia.
  2. Ask the patient to tap the ball of the foot against the floor or your hand in a rhythmic fashion (as if to music: one, two, three; one, two, three). Repeat on the other side and compare. Normally, the movement should be rhythmic and performed without difficulty.
Point-to-point Coordination
1. Finger-to-finger-to-nose test
  1. Ask the patient to use the index finger to touch your finger and then the patient's own nose.
    Have the patient repeat the task, and to do it faster. Move your finger as the patient performs the movement, making the patient search for the target and assess for rapidity, for smooth movements, and for accuracy
  2. Repeat on the other side, and compare. Observe for any side-to-side movements when approaching the target, dysmetria, or an intention tremor, which may be signs of cerebellar disease.
2. Heel-to-knee-to-shin test
  1. With the patient in a supine position, ask the patient to tap the heel under the knee and then run the heel up and down the shin from ankle to knee.
  2. Have the patient repeat it on the other side. Assess for any signs of dysmetria. The ability to perform this task may be compromised by weakness.
Gait and Station
1. Observe the patient sit and then stand. Note the ability to maintain a balanced and upright posture. Then observe the patient walking across the room or down the hall.
2. Observe for the presence of the symmetrical swinging of the arms, a normal rhythm to the gait (including equal transit time of each leg), and signs of spasticity, such as circumduction of one or both legs, or even a diplegic "scissoring" gait. Observe for any abnormal movements such as a tremor or choreiform movements.
3. Observe if the turns are accomplished in a smooth motion or completed in multiple small steps, as may occur in Parkinson's disease.
  1. Specific gait patterns can reflect certain conditions. Some examples of these patterns include:
    Patients with unilateral weakness and spasticity may hold the lower limb stiffly and extended. The patient may drag the weak limb around the body in a circumducting pattern.
    A wide based unsteady gait may suggest cerebellar dysfunction.
    A patient with foot drop (an inability to dorsiflex of foot or toes due to muscle or nerve damage) will tend to lift the effected foot high; this is termed "steppage gait."
    A parkinsonian gait is characterized by small shuffling steps and a general slowness of movement. Patients with Parkinson's disease may have difficulty starting, but also have difficulty stopping after starting, and may feel propelled forward.
Ask the patient to walk on the heels and then on the toes. Walking on the toes tests plantar flexion, and walking on the heels tests the strength of dorsiflexion at the ankles, which helps screen for weakness as may be seen in patients with a foot drop.
Ask the patient to perform tandem walking. Instruct the patient to walk heel touching toe in a straight line (as if walking on a tight rope). Balance and coordination need to be intact to perform tandem walking and heel-and-toe walking. Tandem gait is an excellent test of cerebellar function.
Romberg sign
1. Ask the patient to place the feet together and maintain balance. This is a test of the cerebellar function when done with the eyes open, as cerebellar dysfunction results in impaired balance when in an erect position.
2. Once it's determined that the patient can maintain balance with eyes open, ask the patient to close the eyes. Have your arms prepared to steady the patient.
3. Note if the patient can maintain balance with the eyes closed. Romberg sign is considered positive when the patient can maintain an erect position with the eyes open, but exhibits instability (excessive sway or falling to one side) with the eyes closed. This suggests proprioception (joint position sense) disorder. The cerebellar dysfunction results in excessive sway or instability whether the eyes are open or closed.