1. Peripheral Nerve Injury Neurosurgeon Yoon Seung-Hwan

2. Anatomy Connective tissueConnective tissue - major tissue componant - epineurium, perineurium, endoneurium - epineurium, perineurium, endoneurium Nerve tissueNerve tissue - axon, schwann cell

4. Peripheral Nerve Injury Acute injuryAcute injury Chronic injuryChronic injury (entrapment neuropathy) (entrapment neuropathy)

5. Classification

6. Neuropraxia the mildest form, reversible conduction block loss of function, which persists for hours or days direct mechanical compression, ischemia, mild burn trauma or stretch

7. Axontmetic axon continuity is disrupted fascicular integrity is maintained Wallerian degeneration occurs

8. Neurotmesis laceration from sharp or blunt forces the only important consideration is the timing of repair acute repair or more bluntly lacerated nerves are repaired 3-4 weeks

9. Factor s for Decision Making AgeAge Segment between injury and end organSegment between injury and end organ Gap of injuryGap of injury Mechanism of injuryMechanism of injury Severity of injurySeverity of injury Presence of painPresence of pain

10. Axonal Regeneration Initial delayInitial delay to the distal stump : 1-2 week delay to the distal stump : 1-2 week delay Growth rateGrowth rate 1mm/day, 1 inch/month 1mm/day, 1 inch/month Terminal delayTerminal delay several weeks-several months several weeks-several months Recovery within 6 weeks  good prognosis

11. Fibrillation potentials and positive sharp waves Acute Denervation

12. Long duration, small amplitude polyphasic motor unit potentials Regeneration

13. Clinical Signs Motor functionMotor function Tinel’s signTinel’s sign positive-sensory function positive-sensory function negative(after 4-6weeks)-total interruption negative(after 4-6weeks)-total interruption Sweating-sympathetic fiberSweating-sympathetic fiber Sensory functionSensory function Diagnosis

14. Tinel’s sign advancing along the anatomical distribution of the nerve, particularly if it is does so at the expected rate of nerve regeneration, then this provides evidence of ongoing regeneration.

15. Electrophysiological Tests EMGEMG SNAPSNAP SSEPSSEP Intraoperative NAPIntraoperative NAP Diagnosis

16. EMGSNAP

17. SSEP

18. Intraoperative NAP

19. Muscle Atrophy 24 month rule24 month rule -2 년 이상 지속 시 muscle scar tissue 로 대치되기 때문 에 ( 비가역변화 ) 회복불가 Muscle atrophyMuscle atrophy start : post-injury 1 month start : post-injury 1 month peak : 3 rd - 4 th month peak : 3 rd - 4 th month Segment between injury and end organSegment between injury and end organ

20. Time of Operation Open injuryOpen injury Early intervention Early intervention Delayed intervention Delayed intervention Closed injuryClosed injury Delayed intervention Delayed intervention Treatment

21. Early Intervention Enlarging hematoma/aneurysmal sacEnlarging hematoma/aneurysmal sac Predisposing to Volkmann’s ischemic contracturePredisposing to Volkmann’s ischemic contracture Severe noncausalsic pain SDSevere noncausalsic pain SD Injury to N. in areas of potential entrapmentInjury to N. in areas of potential entrapment Simple, clean lacerating injurySimple, clean lacerating injury

22. Delayed Intervention 2-3 months after injury2-3 months after injury No clinical or substantial recoveryNo clinical or substantial recovery 장점 장점 1. 손상범위를 정확히 알 수 있다. 1. 손상범위를 정확히 알 수 있다. 2. 동반손상의 치유로 감염을 줄인다. 2. 동반손상의 치유로 감염을 줄인다. 3. Epineurium 이 두꺼워져 봉합이 쉽다. 3. Epineurium 이 두꺼워져 봉합이 쉽다. 4. 계획수술로 정확한 수술이 가능하다. 4. 계획수술로 정확한 수술이 가능하다.

23. Operations Neurolysis : internal/externalNeurolysis : internal/external Nerve repairNerve repair end-to-end repair : epineural/fascicular end-to-end repair : epineural/fascicular autologous graft : sural N. autologous graft : sural N. NeurotizationNeurotization intercostal N./accessory N./cervical plexus intercostal N./accessory N./cervical plexus within 1 year within 1 year Muscle and tendon transferMuscle and tendon transfer

24. Epineural Repair

25. Fascicular Repair

26. Nerve Graft # leading cause of failure of nerve graft Inadequate resectionInadequate resection Distraction of repair siteDistraction of repair site

27. Postoperative Care Neurolysis : 수술직후부터 운동시작Neurolysis : 수술직후부터 운동시작 End-to-end repair :3 주 이상 고정End-to-end repair :3 주 이상 고정 6 주까지 서서히 운동 6 주까지 서서히 운동 Graft: 좀 더 일찍 운동 허용Graft: 좀 더 일찍 운동 허용 과도한 관절운동은 피한다 과도한 관절운동은 피한다

28. Injured Peripheral Nerve

29. Evaluation of Closed Injury

30. Conclusions 1. Immediate primary repair in sharp injuries with suspected transsection of nerve Immediate repair is especially important for brachial plexus and sciatic nerve transsections because delay leads not only to retraction but also to severe scaring Bluntly transsected nerve best repaired after a delay of several weeks. 2.A focally injured nerve should be explored if no functional return within 8-10 weeks 3. Decision - making as to whether neurolysis or resection & repair in a lesion in gross continuity based on intraoperative electrophysiological evaluation

31. 4. Split repair with usually graft - lesion in continuity 가 partial function or undergoing partial regeneration 5. Careful patient selection for operation - 특히 plexus involved 시 6. Nerve anastomosis 의 failure 주원인은 ① inadequate resectin of scarred nerve ends ① inadequate resectin of scarred nerve ends ② nerve suture distration ② nerve suture distration 7. A good end result requiring rehabilitation from onset of treatment. Prevention of disuse, relief of pain, predicting probable end results of operative procedures. Conclusions

32. Chronic Injuries of Peripheral Nerves by Entrapment PainPain ParesthesiaParesthesia Loss of functionLoss of function

33. Pathophysiology of Entrapment Direct compressionDirect compression segmental demyelination segmental demyelination wallerian degeneration(distal) wallerian degeneration(distal) IschemiaIschemia swelling of nerve swelling of nerve microcompartment SD microcompartment SD

34. Conservative Tx IndicationsIndications not long history not long history mild-moderate, intermittent mild-moderate, intermittent reversible cause reversible cause pregnancy, oral contraceptive, endocrine abnormalities(DM…), type writer pregnancy, oral contraceptive, endocrine abnormalities(DM…), type writer MethodMethod nonsteroidal anti-inflammatory drugs nonsteroidal anti-inflammatory drugs splint splint Treatment

35. Surgical Indications Failed conservative txFailed conservative tx Typical clinical findingTypical clinical finding with electrodiagnostic data with electrodiagnostic data SevereSevere sensory loss sensory loss muscle atrophy muscle atrophy motor weakness motor weakness Treatment

36. Entrapment of Thoracic Outlet 원 인 원 인 -Cervial rib or anomalous transverse process of C7 -Cervial rib or anomalous transverse process of C7 -Fibromuscular bands or scalene muscle abnomality 진 단 진 단 - X-ray - NCV & EMG - Angiography – vascular anomaly Tx : Supraclavicular approachTx : Supraclavicular approach - Best op. management

37. scalene anterior and medius M.

38. Carpal Tunnel Syndrome

39. thenal atrophy

42. Entrapment of Radial Nerve

43. Entrapment of Ulnar Nerve - Cubital tunnel - Guyon’s canal

44. Motor Deficit of Ulnar Nerve Bediction posture:clawing of ring & small fingerBediction posture:clawing of ring & small finger Froment’s sign : weakness of adductor pollicis, there will be flexion of the interphalangeal joint of the thumb because of substitution of the median innervated flexior pollicus longus for a weak adductor pollicisFroment’s sign : weakness of adductor pollicis, there will be flexion of the interphalangeal joint of the thumb because of substitution of the median innervated flexior pollicus longus for a weak adductor pollicis

47. Meralgia Paresthesia Lateral femoral cutaneous nerve injury (L1-2)

48. Tarsal Tunnel Syndrome