Nerve injuries extend from simple nerve compression lesions to complete nerve injuries and severe lacerations of the nerve trunks. A specific problem is brachial plexus injuries where nerve roots can be ruptured, or even avulsed from the spinal cord, by traction. An early and correct diagnosis of a nerve injury is important. A thorough knowledge of the anatomy of the peripheral nerve trunk as well as of basic neurobiological alterations in neurons and Schwann cells induced by the injury are crucial for the surgeon in making adequate decisions on how to repair and reconstruct nerves. The technique of peripheral nerve repair includes four important steps (preparation of nerve end, approximation, coaptation and maintenance). Nerves are usually repaired primarily with sutures applied in the different tissue components, but various tubes are available. Nerve grafts and nerve transfers are alternatives when the injury induces a nerve defect. Timing of nerve repair is essential. An early repair is preferable since it is advantageous for neurobiological reasons. Postoperative rehabilitation, utilising the patients' own coping strategies, with evaluation of outcome are additional important steps in treatment of peripheral nerve injuries. in the rehabilitation phase adequate handling of pain, allodynia and cold intolerance are emphasised. Scand J Surg. 2008;97(4):310-6

1. Muntasir Mannan Choudhury
Dept of Hand and Reconstructive Microsurgery
Singapore General Hospital
TECHNIQUES AND TIPS IN MICROSURGICAL
NERVE REPAIR

2. INDICATIONS FOR EXPLORATION AND NERVE
REPAIR
• Loss of sensation after an injury
• Complete paralysis after a wound over a major nerve
• Complete paralysis after surgery or an injection near that nerve
• Complete paralysis after a closed injury- high-energy injuries
• A nerve lesion associated with an arterial injury
• A nerve lesion with fracture or dislocation requiring urgent ORIF
• Worsening nerve injury while under observation
• Failure of recovery in the expected time after a closed injury
• Treatment of a painful neuroma

3. CONTRAINDICATIONS
• The general condition of the patient.
• Skills of the operating team, availability of
equipment.
• Uncertainty about the viability or state of the
nerve trunks –eg. nerve has been torn by a saw
or by a bullet.
• The risk for local or systemic sepsis
• Condition more rapidly restored by tendon
transfer.

4. NERVE REPAIR
• Two basic categories:
• Direct repair (neurorrhaphy)
• Bridge procedures

5. • Make yourself comfortable
• Explore
• Identify
• Debride and prepare
• Do it under loupe magnification
• Know your tools

6. YOU WILL BE FACING SITUATIONS LIKE THIS
Or like this

7. • Explore
• Identify
• Debride and prepare

8. SURGEON POSITIONING – BE COMFORTABLE,
AVOID FATIGUE
Greens

9. MICROSCOPE

10. MICROSCOPE – WHAT IS INVOLVED?
• Parts
• Penny towels
• Foot pedals
• TV screen

11. MICROSURGEON AND THE MICROSCOPE
• Comfortable positioning
• Lots of sterile towels for elbows
• Lots of preferences
• Instrument quality
• Instrument layout / positioning
• Sutures
• Music

12. INSTRUMENTS
Jeweler's forceps, straight scissors, jeweler’s forceps, needle holder,
curved scissors

13. PRINCIPLES AND STEPS OF NERVE REPAIR
• Meticulous microsurgical techniques,
microsurgical instruments, and
sutures
• Complete debridement to healthy nerve tissue
• Nerve approximation without tension
• End-on alignment of fascicles
• Atraumatic and secure mechanical coaptation of nerve ends
• MICROSURGICAL REPAIR OF PERIPHERAL NERVES AND NERVE
GRAFTS:TERENCE M. MYCKATYN AND SUSAN E. MACKINNON

14. DEBRIDEMENT
• For sharp, clean lacerations-
minimal debridement
• Subacute, chronic injuries,
injuries with a large zone
• substantial resection may
be necessary until all of the
injured or compromised
nerve tissue has been
removednerve

15. TECHNIQUES OF NERVE APPROXIMATION
• Small gaps can be repaired primarily
• Mobilizing
• Transposing the ends of the nerve
• Bone shortening ( replant situation)
• Relief of tension by joint positioning
• 10% of tension acceptable
• A single 8-0 nylon suture should be enough to maintain the
coaptation.

16. MOBILIZING

17. TRANSPOSITION

18. NERVE GRAFTING

19. TECHNIQUES OF ALIGNMENT
• Knowing the
topography of the
nerves

20. TECHNIQUES OF ALIGNMENT
• Varying size of the fascicles,
orientation of epineurial blood vessels
• Intraoperative electrical stimulation.
• Histological staining
• Carbonic anhydrase staining
identifies sensory fascicles
• Acetylcholinesterase staining
identifies motor fascicles
• Management of acute nerve injuries of
the hand; Olivia M Flannery, Simon J
Roche, Chye Yew NgMINI-
SYMPOSIUM: HAND INJURIES

21. TYPES OF NERVE REPAIR
EPINEURAL REPAIR
• Shallow placement of the stitches minimizes
scar tissue
• Least technically demanding.
• However, fascicular alignment is obtained
indirectly and is prone to error.
• Tendency is to perform this repair too tightly,
resulting in a perfect-appearing outer nerve
surface with bunched up, misdirected fascicles
inside.

22. TYPES OF NERVE REPAIR:
GROUP FASCICULAR REPAIR

23. • Although group fascicular repair ensures
correct matching of the fascicles, it has not
been shown to be superior to simple
epineural repair
• Lundborg G et al : Tubular versus conventional repair of median and ulnar nerves in the
human forearm:Early results from a prospective,randomized, clinical study. J Hand Surg
[Am] 1997;22:99-106.

24. FRESHEN THE NERVE ENDS

25. HOLDING THE SUTURE, THROWING YOUR FIRST
STITCH

26. TYING THE KNOT

27. YOUR 2ND STITCH

29. FIBRIN GLUE APPLICATION

30. SOME CRITICAL POINTS TO REMEMBER

31. CRITICAL POINTS FOR SUCCESSFUL MICROSURGERY
• You must be in a comfortable sitting position
• The arms, forearms, and hands should be adequately
supported
• The height of the chair and the height of the microscope
should be set for comfort
• Nerves should be dissected out of the zone of injury
• The nerves should be sewn under no tension
• Take your time, do not hurry

32. THANK YOU