DEEP TENDON REFLEXES: CERVICAL SPINE AND UPPER EXTREMITIES: There are three basic deep tendon reflexes, which evaluate the integrity of the C5, C6 and C7 nerve supply. These are known as the biceps reflex, the Brachioradialis reflex, and the triceps reflex. Deep tendon reflexes are considered a lower motor reflex. Here the signal translates to the posterior horn of the spinal cord, thought internuncial neurons into the anterior horn cells and returning through the peripheral nerves to the musculature. BICEPS REFLEX â€“ C5 Although there are multiple innervations to the biceps via C5 and C6, primary innervation is associated with C5. BRACHIORADIALIS REFLEX â€“ C6 Although there are multiple innervations to the Brachioradialis via C5 and C6, primary innervation is associated with C6. TRICEPS REFLEX â€“ C7 The triceps muscle is innervated by the radial nerve primarily C7. LUMBOSACRAL SPINE AND LOWER EXTREMITIES: PATELLAR REFLEX â€“ L2, 3, AND 4 Although the patella reflex, or knee jerk, is a deep tendon reflex, innervated by L2, L4 and L4 primary innervation comes from L4. ACHILLES TENDON REFLEX â€“ S1 The S1 nerve level innervates the Achilles tendon deep reflex. COMPLETE LIST OF THE DEEP TENDON REFLEXES 1. Maxillary reflex aka Jaw Jerk innervation Cranial Nerve V3. When there is a sudden closure of the jaw when you strike the middle of the chin, as the mouth was initially open. 2. Bicep reflex C5 primarily (C6) 3. Triceps reflex C6 primarily (C7) 4. Periosteoradial C7 primarily (C6, C8) 5. Periosteo-Ulnar reflex C8, T1. There is extension and ulnar abduction of the wrist when the styloid process of the ulna is struck. 6. Wrist Reflexes C7, C8. There is flexion or extension motion when the corresponding tendons are struck. 7. Patellar reflex L4, (L2, L3). There is extension at the knee when the patellar tendon is struck. Absence of the reflex is known as WESTPHALâ€™S SIGN. When the reflex cannot be obtained and you have the patient clasp their hands together, clench, and the reflex is obtained you have utilized the JENDRASSIK method of reinforcement. 8. Achilles reflex S1, S2. NERVE LEVEL & PERIPHERAL NERVE SENSATION TESTING AND VERIFICATION Sensory testing for the cervical spine is associated with the integrity of the dermatomes. Dermatomes into the upper extremities include levels C5 to T1. The following is an outline the brachial plexus distribution of the upper extremities. C5 â€“ Lateral arm â€“ Axillary nerve C6 â€“ Lateral forearm, thumb, index, and half of middle finger â€“ sensory Branches of the Musculo-Cutaneous nerve. C7 â€“ Middle finger C8 â€“ Ring and little fingers, medial forearm â€“ medial antebrachial-cutaneous nerve. T1 â€“ Medial arm â€“ medial brachial cutaneous nerve. THE SUPERFICIAL REFLEXES The superficial reflexes (i.e. abdominal, cremasteric, and anal reflexes) or upper motor neuron reflex testing is mandatory when we suspect specific lesion associated with an upper motor neuron lesion. The absence of the superficial reflex perhaps indicates an upper motor neuron lesion. If the superficial reflex is absent and the deep tendon reflex is increased, this will add evidence to indicate an upper motor neuron lesion and reason for consultation for Neurodiagnostic testing. ABDOMINAL REFLEX The patient is asked to lie in the supine position. Place the arrow end of the reflex hammer upon the abdomen and stroke each section of the abdomen, noting whether the umbilicus moves toward the area being stroked. The lack of an abdominal reflex may indicate an upper motor neuron lesion provided you perform the test correctly. You may also detect a lower motor neuron lesion because the upper muscles of the abdomen are innervated form T7 through T10. The lower muscles from T10 to L1. Thus, lack of a reflex will indicate the approximate level of a lower motor neuron lesion. CREMASTERIC REFLEX The patient is asked to lie in the supine position. Stroke the inner aspect of the upper thigh with the arrow end of the reflex hammer. If the reflex is elicited the scrotum will be pulled upward as the cremasteric muscle contracts. This is associated with a T12 level. If the reflex is reduced or absent bilaterally this may indicate an upper motor neuro lesion, while a unilateral absence indicates a probable lower motor neuro lesion between L1 and L5. ANAL REFLEX The patient is asked to lie in the prone position. Gently touch the perianal skin. The external and anal sphincter muscles (S2, S3, S4) would contract in response. ANAL WINK REFLEX If you are unable to elicit a response, take a finger cot, place your finger gently within the anus, and pull out. The anus should contract as if to wink. CLINICAL UNDERSTANDING OF UPPER AND LOWER MOTOR NEURON LESIONS The motor innervation of the striated musculature is innervated by the Pyramidal system. The Pyramidal pathway conducts impulses to the spinal cord anterior horn cells associated with isolated movements of the hands ad fingers which form the basis for the development of manual skills. In fact, it has been estimated that 55% of all pyramidal fibers end in the cervical cord, 20% in the thoracic and 25% in the lumbosacral segments. Therefore, the muscles of the upper extremity are more affected than the muscles of the lower extremity and the distal muscles (hand) are most affected compared to the proximal because they have more motor units for complex actions. UPPER MOTOR NEURON LESION AKA SPASTIC PARALYSIS AKA SUPRANUCLEAR PARALYSIS 1. Initially there is loss of tone in the affected muscles (hypertonia) 2. Soon after the muscles gradually become resistant to passive movement and yield SPASTIC PARALYSIS. 3. The myotatic deep tendon reflexes, especially in the leg, are increased in force and amplitude known as HYPERREFLEXIA. 4. The SUPERFICIAL REFLEXES are lost or diminished. 5. Positive Babinskiâ€™s Sign is noted. 6. If the suspected lesion is above the pyramidal decussation, the symptoms will be found on the contralateral side. 7. If the suspected lesion is below the pyramidal decussation, the symptoms will be found on the ipsilateral side. With an upper motor neuron lesion the first manifestation will be a disturbance in muscular tonus, expressed as hypotonia. However, within 2-3 weeks changes occur leading to hypertonia bringing about hyperreflexia. Thus when hyperreflexia is noted the lesion must be considered at least 2-3 weeks old. The reason that UMNLâ€™s lead to a loss of the superficial reflexes is due to the fact that there is retrograde degeneration. This retrograde degeneration causes degeneration of the association neuron and the afferent sensory neuron in the reflex arc. In the geriatric population, there is a tendency for the superficial abdominal reflexes to be absent. Thus, this may not indicate an UMNL. It must also be noted that absence of the superficial abdominal reflexes is not in itself indicated of a MNL. Finally, in UMNLâ€™s flaccidity and atrophy will be greater in the upper extremities in the distal aspect because there are more motor units present. LOWER MOTOR NEURON LESION AKA FLACCID PARALYSIS LESION 1. Muscle fibers, which have been deprived of their afferent nerve innervation, become completely paralyzed. 2. All reflexes, deep tendon and superficial are abolished and the musculature become flaccid. 3. The muscle fibers begin to undergo progressive atrophy. 4. There are marked fibrillary tremors and fasciculations noted in the affected musculature within three weeks of the initial injury. 5. Lower motor neuron lesions produce ipsilateral symptoms except for the Ivth cranial nerve because the IV crosses. It must be noted that when the lesion is found in the anterior horn cells, it will take two weeks or more for paralysis and flaccidity to occur. Generally, marked fasciculations and fibulation occurs while the LMN is degenerating then they disappear. If the fasciculations occur months to years later, it indicates that there is some nerve regeneration. PATHOLOGICAL REFLEXES COMPLETE BY BODY REGION Pathological reflexes act reciprocally to the previous. The presence of a pathological reflex may indicate an upper motor neuron lesion and its absence indicates the norm. HEAD 1. BABINSKIâ€™S PLATYSMA SIGN If resistance to flexion of the chin against the chest is presented or opening the mouth, the platysma on the side will contract, whereas the affected side will not. 2. HEAD RETRACTION REFLEX Specific downward percussion upon the upper lip with the patientâ€™s head slightly in forward flexion produces head and neck bending followed by brisk head retraction. 3. Mc MCCARTHYâ€™S SIGN AKA The Glabella Reflex With the patient in the supine position gently percuss the Supraorbital ridge which results in the reflex contraction of the Obicularis Oculi muscle. 4. SNOUT REFLEX Specific tapping of the middle of the upper lip induces an exaggerated reflex contraction of the lips. UPPER EXTREMITIES 1. BABINSKIâ€™S PRONATION SIGN The patient is in the sitting position. Ask the patient to place their hands in approximation with the palms upward. Place your fists below the patient hand. Bring your fists upward jarring the patientâ€™s hands several times. The affected hand will fall in PRONATION, and the sound hand will remain horizontal. 2. BECTEREWâ€™S SIGN The patient is in the sitting position. Ask the patient to flex and relax the forearms several times. The paralyzed forearm will fall back slowly and in a jerky manner, even when contractures are mild. 3. CHADDOCKâ€™S WRIST SIGN Gently stroke the ulnar side of the forearm near the wrist. Flexion of the wrist, and extension and fanning of the fingers will indicate the affected hand. 4. TROMNERâ€™S SIGNS AKA Finger Flexion Reflex A positive sign is elicited by specifically tapping the palmar surface or the tips of the middle three fingers produces prompt flexion of the fingers. 5. GORDONâ€™S FINGER SIGN Extension of the flexed fingers or the thumb and index finger when pressure is exerted over the Pisiform bone. 6. HOFFMANâ€™S SIGN This sign is demonstrated by a clawing movement of the fingers produced by the flicking of the distal phalanx of the index finger. The thumb is also clawed. 7. FORCED GRASPING TEST Specifically stroke radial ward with your fingers across the patientâ€™s palm causes a grasp reaction of the hand. 8. KLEISTâ€™S HOOKING SIGN Exert pressure with your hand against the patientâ€™s flexor surface of the fingertips. A sudden reactive flexion of the fingers indicates the affected hand. 9. KLIPPEL AND WEIL THUMB SIGN Ask the patient to flex their fingers. Quickly extend the patients fingers with your hand. A positive test is demonstrated by flexion and abduction of the patientâ€™s thumb. 10. LERIâ€™S SIGN Absence of normal flexion of the elbow upon forceful passive flexion of the wrist and fingers. 11. MAYERâ€™S SIGN Ask the patient to supinate their hand. Absence of adduction and opposition of the thumb upon passive forceful flexion of the proximal phalanges, especially of the third and fourth fingers, of the supinated hand. 12. SOUQUEâ€™S SIGN In attempting to raise the paralyzed arm, the fingers spread out and remain separated. 13. STRUMPELLâ€™S PRONATION SIGN Upon the patient flexing the forearm, the dorsum of the hand approaches the shoulder instead of the palm. LOWER EXTREMITIES 1. ANKLE CLONUS The patient is seated or supine. Place your stabilizing hand upper the patient popliteal space. Forcibly and quickly dorsiflex the patientâ€™s foot. A positive test demonstrates and continued rapid flexion and extension of the foot. A rapidly exhaustible clonus may be normal. 2. BABINSKIâ€™S SIGN With the metal end of the reflex hammer, stimulate the plantar surface of the foot from the Calcaneus along the lateral aspect to the forefoot. Seeing the big toe extend while the other toes plantar flex recognizes a positive test. This would indicate an upper motor neuron lesion indicating brain Pathology or trauma. In the newborn, a positive test is normal. Shapiro advices forcible flexing of the second to fifth toes while eliciting the Babinskiâ€™s response in the usual manner, for a more definitive test. 3. CHADDOCKâ€™S SIGN Babinski response obtained by the stroking of the lateral malleolus. 4. CROSSES EXTENSION REFLEX Ask the patient to lie supine on the examining table. Have the patient flex both legs. Stimulate the sole of the foot, which causes extension of the contralateral leg. 5. EXTENSOR THRUST Extension of a flexed lowed limb when the sole of the foot is forced upward. 6. GONDA REFLEX Press one of the patientâ€™s toes downward and release it with a snap. The reflex is an upward movement of the Big Toe. 7. GORDONâ€™S LEG SIGN Squeezing the patientâ€™s calf will elicit a Babinski like response. 8. GASSET AND GAUSSEL SIGN Ask the patient to lie in the supine position. The patient will be able to raise either leg separately but cannot raise both legs simultaneously. If the paralyzed leg is raised, it will fall back heavily when the examiner raises the unaffected leg. 9. HIRSCHBERGâ€™S SIGN Stroke the inner border of the foot. The reflex will cause adduction and internal rotation of the foot. 10. HOOVERâ€™S SIGN With the alleged Hemiplegic patient in the recumbent position, place the palms of your hands directly beneath the patientâ€™s heels, while the patient is asked to pres down Pressure should be felt only from the heel of the non-paralyzed leg. Next remove our hand from beneath the non-paralyzed heel and place it o the dorsum of their foot, and the patient is instructed to raise the healthy leg against this resistance. If the patient has a true organic HEMIPLEGIA, the hand remaining beneath the heel of the paralyzed leg will feel no added pressure. However, if the patient has a hysterical paralysis, the heel of the supposedly paralyzed leg will press down against the examinerâ€™s had as an attempt is made to raise the healthy leg. 11. HUNTINGTONâ€™S SIGN Flexion at the hip, extension at the knee, and elevation of the affected weak lower extremity upon coughing and straining. 12. MARIE AND FOIX RETRACTION SIGN Upon the forcing of the patientâ€™s toes downward, the knee and hip are drawn into flexion (important test). 13. MANDEL-BECHTEREW SIGN Flexor movement of the four outer toes upon striking the dorsum of the foot over the cuboid bone. 14. NERIâ€™S SIGN The patient is in the recumbent position. Ask the patient to alternately raise one leg at a time. The knee of the paralyzed side flexes, the other remaining straight. Forward flexion of the trunk in the standing position causes the paretic lower lib to flex while the normal one remains straight. 15. OPPENHEIMâ€™S SIGN Run the metal handle end of the reflex hammer along the crest of the tibia and the Tibialis anterior muscle. A normal test indicates no reaction or the patient complains of pain. A positive test extends the great toe while the other toes plantar flex. 16. PATELLAR CLONUS AKA TREPIDATION SIGN Forcibly depress the patella with a quick movement while the leg is in extension and relaxed. A positive reflex is a rapid up and down movement. KINESIOLOGY-PERIPHERAL NERVE INTEGRITY TESTING CORRELATED WITH MUSCULAR POWER Kinesiology is defined as that branch of biomechanics, which studies the science of movement. In general, it is divided into two fields of study. 1. Osteokinematics, which is that branch of Kinesiology, which attempts to focus primarily on overall movement of bones, with little reference to their related joints. 2. Arthrokinematic, which is that branch of Kinesiology, which attempt to focus on the intimate and delicate mechanics of joints. MUSCLE TESTING Muscle power 0-5 scale is as follows: 0=Non Contraction (Zero) 1=Flicker of contraction (Trace) 2=Sight power sufficient to move the joint (poor) 3=Power sufficient to move the joint against gravity (fair) 4=Power to move the joint against gravity plus added resistance (good) 5=Normal power with a full range of motion against gravity with full resistance.