1. PERIPHERAL NEVRE DISORDERS AND MANAGEMENT CHAPTER # 13 Dr. Sarah Ehsan

2. Topics to be covered in this lecture: Review of peripheral nerve structure; nerve structure, nervous system mobility characteristics, common sites of injury to peripheral nerves Impaired nerve function Nerve injury and recovery Neural tension disorders and their managements

3. Review of peripheral 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

4. Mobility characteristics of nervous system When a joint moves and tension is placed on a nerve bed, nerve gliding is toward the moving joint (convergence) when tension is relieved, nerve gliding is away from the moving joint (divergence). Substantial mobility in the nervous system is needed for an individual to move during functional activities

5. Mobility characteristics of nervous system How is it that the mobility of the joints is allowed without undue stress on the nerve tissue? How is it that the mobility of the joints is allowed without undue stress on the nerve tissue? The arrangement of the spinal cord, nerve roots, and plexes allows mobility. If any part of the H is placed under tension, the force can be dissipated throughout the system The nerves themselves are wavy and can straighten when tension is applied. The connective tissue around the individual nerves and bundles of nerves (epineurium, perineurium, endoneurium) absorb tensile forces before the nerve itself stretches.

6. Common sites of injury to peripheral nerves Injury to the nerves of the peripheral nervous system can occur anywhere along the pathway there are sites that increase its susceptibility to either tension or compression. Signs and symptoms of nerve impairments: Sensory changes /loss of motor weakness Ischemic pain Autonomic responses

7. Sites of compression Nerve roots (C5-T1, L1-S3) Compression occurs as a result of various pathologies DDD ( degenerative disc disease) DJD ( Degenerative joint disease) Disc lesions Spondylolisthesis Stenosis Adhesions (sysmptoms reproduced on stretching the nerves and bending spine away from the symptomatic side)

8. Sites of compression Brachial plexus the weave pattern in the brachial plexus contributes to the mobility of the nerves such that when tension is placed on any one peripheral nerve, the tension is transmitted to several cervical nerve roots rather than just one nerve root

9. Upper plexus injuries ( C5,6) Shoulder Depression and lateral flexion of neck to the opposite side Erb’s Palsy – shoulder stretched down A “stinger” occurs with injuries that might be sustained when a football player lands on the upper torso and shoulder with the head/neck laterally flexed in the opposite direction. Middle plexus injuries ( C7) rare Lower plexus injuries ( C8,T1) Klumpke’s paralysis- compression by cervical rib, baby presents with overhead arm Complete plexus injury Erb’s-Klumpke’s paralysis –Horner’s syndrome

10. Dermatomes

11. Myotomes

12. Peripheral nerves in upper quadrant

14. Peripheral Nerves in lower quadrant

15. What are the Areas of sensory distribution of peripheral nerves of upper and lower quadrant?

16. Impaired Nerve Function motor, sensory, and/or sympathetic impairments. pain may be a symptom of nerve tension or compression because the connective tissue and vascular structures surrounding and in the peripheral nerves are innervated and the peripheral nerve function is sensitive to hypoxic states. Nerve Injury and Recovery

17. Mechanism of injury Nerves are susceptible to various types of injuries: 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). Most common causes are compression, friction and stretch

18. Mechanism of injury Compressive forces can affect the microcirculation of the nerve, causing venous congestion and reduction of axoplasmic transport. The endoneurium helps maintain fluid pressure and may provide cushioning for nerve Response to injury can be pathophysiological or pathomechanical. Intraneural: conducting tissues or connective tissues of nerves. Extraneural: Pathology that affects the nerve bed (e.g., blood), adhesions of epineurium to another tissue.

19. Sites of compression Insult can be acute and chronic ( repetitive and entrapment neuropathy) tunnels (soft tissue, boney, fibroosseus), branches of the nervous system (especially if the nerve has an abrupt angle), points at which a nerve is relatively fixed when passing close to rigid structures (across a boney prominence), and at specific tension points

20. Classification of nerve injuries Seddon’s OR Sunderland’s classification

21. Comparison of Sedon’s & Sunderland’s classification

22. Recovery from nerve injuries Nerve tissue that has become irritated from tension, compression, or hypoxia may not have permanent damage and shows signs of recovery when the irritating factors are eliminated. recovery is dependent on several factors: Nature and level of injury Timing and technique of repair Age and motivation of the patient

23. Management Guidelines- recovery from nerve injury Acute phase. This is early after injury or surgery when the emphasis is on healing and prevention of complications. Recovery phase. This is when reinnervation occurs. Emphasis is on retraining and re-education. Chronic phase. This occurs when the potential for reinnervation has peaked, and there are significant residual deficits. The emphasis is training compensatory function.

26. Neural tension disorders Signs and symptoms of impaired nerve mobility Pain Sensory response – stretch pain, paraesthesia Tests of provocation Neurodynamic test manoeuvres to detect tension signs in neural tissue Provocative symptoms are stretch pain and paraesthesia Causes of symptoms: Compression – tension signs above or below the level Inflammation and scarring leading to restrictions

27. Principles of management Neural tension technique Application of the techniques requires positioning the trunk and extremity at the point of tension (symptoms just begin), then either passively or having the patient actively moving one joint in the pattern in such a way as to stretch and then release the tension. Moving different joints in the pattern while maintaining the elongated position on the other joints changes the forces on the nerves. Neural glide technique Positioning the individual is the same as with the tension technique (at point of tension), but the movement involves moving two joints in the chain, so the tension remains the same but the neural tissue glides proximally or distally. For example, once at the position of tension, perform elbow flexion simultaneously with cervical contralateral flexion, or wrist flexion simultaneously with elbow flexion to glide the median nerve proximally. Stretch force duration 15-20 seconds

28. PRECAUTIONS Know what other tissues are affected by the positions and maneuvers. Recognize the irritability of the tissues involved and do not aggravate the symptoms with excessive stress or repeated movements. Identify whether the condition is worsening and the rate of worsening. A rapidly worsening condition requires greater care than a slowly progressing condition. Use care if there is an active disease or pathology affecting the nervous system. Watch for signs of vascular compromise. The vascular system is in close proximity to the nervous system and at no time should show signs of compromise when mobilizing the nervous system.

29. CONTRAINDICATIONS Acute or unstable neurological signs Cauda equina symptoms related to the spine including changes in bowel or bladder control and perineal sensation Spinal cord injury or symptoms Neoplasm and infection

30. Neural Testing and Mobilization Techniques for the Upper Quadrant Median Nerve Begin with the patient in supine; sequentially apply shoulder girdle depression, then slightly abduct the shoulder, extend the elbow, laterally rotate the arm, and supinate the forearm. Wrist, finger, and thumb extensions are then added; finally, the shoulder is taken into greater abduction. The full stretch position includes contralateral cervical side flexion. While maintaining the stretch position, move one joint at a time a few degrees in and out of the stretch position, such as wrist extension and flexion or elbow flexion and extension.

31. Neural Testing and Mobilization Techniques for the Upper Quadrant Radial Nerve Stretch maximum stretch on the radial nerve includes shoulder girdle depression; shoulder abduction; elbow extension; shoulder medial rotation and forearm pronation; wrist, finger, and thumb flexion; wrist ulnar deviation; and finally contralateral cervical side flexion.

32. Neural Testing and Mobilization Techniques for the Upper Quadrant Ulnar nerve stretch Position of maximum stretch on the ulnar nerve includes shoulder girdle depression; shoulder external rotation and abduction; elbow flexion; forearm supination and wrist extension; and finally contralateral cervical side flexion.

33. Neural Testing and Mobilization Techniques for the Lower Quadrant Sciatic Nerve Stretch Position of stretch on the sciatic nerve includes straight-leg raising with adduction and internal rotation of the hip and dorsiflexion of the ankle.

34. Neural Testing and Mobilization Techniques for the Lower Quadrant Femoral Nerve Stretch femoral nerve; prone lying with the spine neutral, hip extended to zero degrees, and knee flexed. It is important to maintain the spine in neutral and not allow it to extend.

35. Neural Testing and Mobilization Techniques for the Lower Quadrant Slump Test