Repair

Grafts, Neurotizations, Upper Palsy, Complete Palsy

Surgical repair

The type of surgical repair will depend from the type and extension of lesions. In presence of a sharp wound of the plexus either very proximal (root’s level) or more distal (cord’s level) the repair will be easily done by a neurorraphy.
In presence of postganglionic lesions, that is rupture of the roots in which either proximal and distal portion of the ruptured nerve are present, the gold standard of repair is to re establish the continuity of the nerve by means of nerve grafts.
This repair will be more or less complete depending on the number of roots stump available to be repaired. The problems start with the very frequent association of root avulsion that means no proximal stumps available to allow an anatomical reconstruction of the nerve gap with grafts.



This repair will be more or less complete depending on the number of roots stump available to be repaired. The problems start with the very frequent association of root avulsion that means no proximal stumps available to allow an anatomical reconstruction of the nerve gap with grafts.

In these situations the only option is to try to repair the distal part of a nerve which lack of its proximal connection by means of neurotizations.
Neurotization can be defined as a nerve transfer or nerve by pass in order to bring nerve sources out of the plexus to re-innervate distal stumps no more connected with the proximal ones.
If in a multiple root avulsion lesions we can find at least one or two root’s stump the grafts will be distributed from the remaining roots to the entire distal part of the plexus. This will be defined as an intraplexal neurotisation. Examples of extraplexal neurotisation are spinal accessory nerve sutured to suprascapular nerve in avulsion of upper roots or intercostals nerves sutured to musculocutaneous nerve in total palsies or contralateral healthy C7 root used to bring re-innervation to the avulsed roots.
Since to perform a neurotization we must intentionally section an healthy nerve, we must carefully evaluate the balance cost-benefit in order to concentrate on a unique target a nerve or a portion of it avoiding to provoke a substantial loss of function at the donor site.
It is obvious that neurotization offer a limited repair and, especially in extended palsies, must be multiple (accessory nerve, intercostals nerves, contralateral C7 etc).

Strategy of Repair

Upper palsies C5 C6 –C5 C6 C7

C5 C6

The C5 C6 lesion is very common. The roots can be ruptures or avulsed.
There are case were one root is avulsed and the other ruptured.
ONLY EXPLORATION OF THE ROOTS CAN GIVE AN EXACT VIEW OF THE SITUATION

The preferable way of repair is grafting between the good stump and the distal trunks . It implies a precise assessment of the quality of the stumps , sometimes using chemical staining , often ,with experience , by clinical examination . Only grafting can give a recovery of the whole muscle groups innervated by the upper roots .

Neurotizations can be very useful when the roots are avulsed or when they have a poor quality . The most common neurotizations are :

  • Spinal Accessory nerve to Suprascapular nerve
  • Median or Ulnar fascicle to Biceps or/and Brachialis nerves.
  • One of Triceps branch to part of the Axillary nerve.
There are other , less common , neurotizations using Intercostal or Pectoralis nerves .

Strategy

If we have 2 usable roots :
  • C5 C6 (post) : posterior division of upper trunk
  • C5 C6 (ant) : anterior division of upper trunk
  • C5 to suprascapular nerve
  • If C5 poor : Spinal accessory to SS nerve
  • If C6 poor : biceps neurotization with ulnar nerve
If we have 1 good root and one avulsed :
  • Neurotization of SS by Spinal Accessory
  • Graft to upper trunk
  • Sometimes neurotization Biceps with Ulnar nerve.
If the 2 roots are avulsed :
  • Neurotization : SS by S. Acc
  • Neurotization : Biceps by Ulnar nerve
  • Neurotization : Axillary with Triceps branches

C5 C6 C7

The association of a C7 lesion makes the repair much more difficult in case of avulsion, as the ulnar nerve and the Triceps may be involved.

Strategy

If we have 3 ruptures roots :
  • Graft to upper and middle trunk
If we have only one or two roots intact
  • Association of graft and neurotizations
If we have 3 avulsions : difficult situation : each case is different
  • Spinal acc to SS in all cases
  • Biceps reconstruction function of the quality of ulnar nerve. If no good : intercostal nerves transfer
  • Problem with axillary, triceps, wrist extensors if they are all paralysed.

We have no possibility to repair by nerve surgery all the functions. Some neurotizations are possible in the arm (intercostal) or in the forearm (FCR, pronator) but it will be necessary to add some secondary tendon transfers (especially in the wrist).

Complete brachial plexus injury

When all roots and especially the lower (C8 T1) roots are injured, it is called complete brachial plexus.
In most cases, unfortunately, the lower roots are avulsed from the spinal. They have no chance of spontaneous recovery.
Up to now, the treatment of complete brachial plexus has been limited to repair by grafts or neurotizations of the upper plexus in order to recover movements in the shoulder and elbow. A part from the rare case where the lower roots were ruptured and could be repaired, the attempts of reinnervation of the hand muscles by grafts, or neurotizations by intercostal nerves have given very poor results and in most cases, the hand has been abandoned.

(Photos – film )

A new perspective has been operated by the chinese authors, using the contro-lateral C7 root. Although the CC7 transfer with graft has not changed dramatically the prognosis, its use with a direct coaptation to the lower has proven in many cases very effective (WANG).

We are now using this technique either alone or combining it with other techniques when possible.

Strategy

  1. Complete palsy with C5 C6 or C7 intact :
    • The upper roots are used to recover the shoulder (Suprascapular nerve and axillary nerve) and the elbow (Biceps and Triceps).
    • CC7 using the pre-spinal route is used for the hand.
    • If these is early 1 root, it is necessary to add the Phrenic nerve transfer for the posterior branch (Triceps – Fingers and wrist extensors) and a part of CC7 for Biceps.
  2. Complete palsy with 5 avulsions :
    • The spinal accessory is used for supra-scapular nerve.
    • The Phrenic nerve to posterior branch of Anterior and middle trunk
    • The CC7 to Biceps and Lower Trunk.
  3. The contro-lateral C7 operation (Shufang WANG) by pre-spinal root
The donor site is the C7 root on the opposite site. The root is cut as distally as possible and passed posterior to the oesophagus and anterior to the vertebra.

On the other side, the Lower Trunk (C8 and T1) is mobilized form the arm to the foramen allowing, if possible, a direct suture with the opposite C7 root. The direct suture is very important for the quality of recovery and if a few centimetres are missing, it is preferable to shorten the humerus in order to allow a suture without tension rather than to use a graft. The consequences of harvesting the C7 root are limited : paresthesias in the thumb and index, weakness of the Triceps or Finger extensors. These anomalies usually disappear after a few months. There may be initially some difficulties to use the recovered hand by moving the opposite arm but after some learning, the control is good.