Peripheral nerve disorders

therapeutics

1. Peripheral Nerve Disorders and Management Dr. Maria Idrees ; PT

2. Review of Peripheral Nerve Structure Nerve Structure Peripheral nerves contain a mix of motor, sensory, and sympathetic neurons. ■ Alpha motor neurons (somatic efferent fibers): cell bodies located in anterior column of spinal cord; innervate skeletal muscles ■ Gamma motor neurons (efferent fibers): cell bodies located in lateral columns of spinal cord; innervate intrafusal muscle fibers of the muscle spindle ■ Sensory neurons (somatic afferent fibers): cell bodies located in the dorsal root ganglia; innervate sensory receptors ■ Sympathetic neurons (visceral afferent fibers): cell bodies located in sympathetic ganglia; innervate sweat glands, blood vessels, viscera, and glands

3. Mobility Characteristics of the Nervous System H ???

4. Common Sites of Injury to Peripheral Nerves A nywhere along the pathway from the nerve roots to their termination in the tissues of the trunk and extremities . Inter vertebral foramen Symptoms and signs of nerve impairments are sensory changes or loss and motor weakness in the distribution of the involved nerve fibers

5. Nerve Roots Nerve roots emerge from the spinal canal and traverse the foramina of the spine, where they can become impinged as a result of various pathologies of the spine that reduce the space in the foramina, such as degenerative disc disease (DDD ), degenerative joint disease (DJD), disc lesions, and spondylolisthesis . With reduced spinal canal or foraminal space ( stenosis ), extension, side bending, or rotation to the side of the stenosis further decreases the space where the nerve root courses and may cause or perpetuate symptoms Nerve roots of the upper quarter include C5 through T1 and those of the lower quarter L1 through S3.

6. Brachial Plexus

7. Sites of compression

8. Upper plexus injuries (C5, 6 ): The mechanism involves shoulder depression and lateral flexion of the neck to the opposite side. There is loss of abduction and lateral rotation of the shoulder and weakness in elbow flexion and forearm supination ( waiter’s tip position ). Erb’s palsy occurs with birth injuries when the shoulder is stretched downward. Middle plexus injuries (C7): Rarely seen alone . Lower plexus injuries (C8, T1): Usually due to compression by a cervical rib or stretching the arm overhead. Klumpke’s paralysis (paralysis of the intrinsics of the hand ) occurs in birth injuries when the baby presents with its arm overhead . Complete or total injury of the plexus: Erb-Klumpke’s paralysis ( Horner’s syndrome)

9. Myotomes

10. Lumbosacral Plexus

11. Mechanisms of Nerve Injury ■ Compression (sustained pressure applied externally, such as tourniquet , or internally, such as from bone, tumor, or soft tissue impingement resulting in mechanical or ischemic injury ). ■ Laceration (knife, gunshot, surgical complication, injection injury ). ■ Stretch (excessive tension, tearing from traction forces). ■ Radiation. ■ Electricity (lightening strike, electrical malfunction ). Intraneural Extraneural

12. Excellent regenerative potential: radial, musculocutaneous , and femoral nerves Moderate regenerative potential: median, ulnar , and tibial nerves Poor regenerative potential: peroneal nerve

13. Outcomes of Nerve Regeneration F ive possible outcomes of nerve regeneration. 1. Exact reinnervation of its native target organ with return of function 2. Exact reinnervation of its native target organ but no return of function due to degeneration of the end organ 3. Wrong receptor reinnervated in the proper territory; therefore, improper input 4. Receptor reinnervation in wrong territory causing false localization of input 5. No connection with an end organ

14. Management Guidelines: Recovery from Nerve Injury Acute Phase Movement Splinting or bracing Patient education Recovery Phase Motor retraining Desensitization . Patient education Chronic Phase Compensatory function

15. Suggestions for graded modalities and procedures for desensitizing: ■ Use multiple types of textures or contact for sensory stimulation , such as cotton, rough material, sandpaper of various grades, and Velcro. The textures can be wrapped around dowel rods for finger manipulation or to stroke along the skin. ■ Place contact particles, such as cotton balls, beans, macaroni , sand, or other material, with various degrees of roughness in tubs or cans, so the patient can run the involved hand or foot through the material. Have the patient begin by manipulating or placing the extremity in the least irritating texture for 10 minutes. As tolerance improves , progress to the next texture of slightly more irritating but tolerable stimulus. Maximum progress occurs when the most irritating texture is tolerated. ■ Use vibration. Pattern of recovery after nerve injury is pain (hypersensitivity ), perception of slow vibration (30 cps ), moving touch, constant touch, rapid vibration (256 cps ), and awareness from proximal to distal.

16. Suggestions for retraining the brain to recognize a stimulus ■ Begin by using a moving touch stimulus, such as the eraser end of a pencil, and stroke over the area. The patient first watches , then closes his or her eyes, and tries to identify where touch occurred. ■ Progress from stroking to using constant touch. ■ When the patient is able to localize constant touch, progress to identification of familiar objects of various sizes , shapes, and textures. ■ For the hand, use familiar household and personal care objects , such as keys, eating utensils, blocks, toothbrush, and safety pins. ■ For the feet, have the patient walk on various surfaces, such as grass, sand, wood, pebbles, and uneven surfaces.

17. Neural Testing and Mobilization Techniques for the Upper Quadrant Median Nerve Radial Nerve Ulner Nerve

18. Neural Testing and Mobilization Techniques for the Lower Quadrant Sciatica Nerve Slump sitting Femoral Nerve