Reinforcement is accomplished by asking the patient to clench their teeth, or if testing lower extremity reflexes, have the patient hook together their rippled fingers and pull speciaal. This is known spil the Jendrassik maneuver.
It is key to compare the strength of reflexes elicited with each other. A finding of Trio+, brisk reflexes via all extremities is a much less significant finding than that of a person with all Two+, regular reflexes, and a 1+, diminished left ankle reflex suggesting a distinct lesion.
Have the patient sit up on the edge of the examination bench with one forearm on top of the other, arms and gams relaxed. Instruct the patient to remain relaxed.
The biceps and brachioradialis reflexes are mediated by the C5 and C6 nerve roots.
The triceps reflex is mediated by the C6 and C7 nerve roots, predominantly by C7.
The knee wank reflex is mediated by the L3 and L4 nerve roots, mainly L4.
Insult to the cerebellum may lead to pendular reflexes. Pendular reflexes are not brisk but involve less damping of the limb movement than is usually observed when a deep tendon reflex is elicited. Patients with cerebellar injury may have a knee wank that swings forwards and rearwards several times. A habitual or brisk knee wank would have little more than one sway forward and one back. Pendular reflexes are best observed when the patient’s lower gams are permitted to dangle and sway freelly off the end of an examining table.
The ankle wank reflex is mediated by the S1 nerve root.
A positive Babinski’s sign is indicative of an upper motor neuron lesion affecting the lower extremity ter question.
A positive Hoffman response is indicative of an upper motor neuron lesion affecting the upper extremity ter question.
Sciatica is the clinical description of ache te the gam that occurs due to lumbrosacral nerve root compression usually secondary to lumbar disc prolapse or extrusion. L5/S1 disc level is the most common webpagina of disc herniation. The following are the characteristic “lower back syndromes” associated with nerve root compression. Note that disc herniations are mostly ter the posterolateral direction, thus compression of the nerve root exiting from the vertebral foramen at one level below is affected. (The nerve root at the same level of the herniation is already within the vertebral foramen and therefore not compressed)
L5/S1 Disc Prolapse
- Ache along posterior hip with radiation to the intact
- Weakness on plantar flexion (may be absent)
- Sensory loss ter the pegado foot
- Absent ankle wank reflex
L4/L5 Disc Prolapse
- Anguish along the posterior or posterolateral hip with radiation ot
- the top of the foot
- Weakness of dorsiflexion of the superb toe and foot
- Paraesthesia and numbness of top of foot and excellent toe
- No reflex switches noted
L3/L4 Disc Prolapse
- Anguish ter vuurlijn of hip
- Wasting of quadriceps muscles may be present
- Diminished sensation on the voorzijde of the hip and medial lower gam
- Diminished knee jack reflex
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