Plexus Repair

Neurotizations, Nerve Transfers, Obstetrical Palsy Repair

There are two types of surgeries that are done. The "primary surgery" involves exploration and nerve repair (grafting). There are also many types of "secondary" procedures that may be necessary.

Plexus Repair with grafts

This operation is done at the age of 3 months or shortly after. lt is possible to do it later when the child is seen too late (up to 2 or 3 years) but in the older child, the quality of recovery seems to be lower.

The operation is done under general anesthesia. The wound is infiltrated with 1/1000 adrenalin in order to avoid bleeding: in our series of 1.000 babies operated on, blood transfusion was never necessary.

The incision is supra clavicular for access to an upper roots lesion (C5, C6, C7) or supra and infraclavicular for a complete lesion (in the drawing the red arrows show the extent of supra and infraclavicular lesion).

In these cases we feel that the osteotomy of clavicle is mandatory and gives a better and less risky access to the lower roots. The arrows show the level were the damaged nerves are resected. The clavicle is repaired and will heal in two weeks.



1. Drawing of the incisions and preoperative infiltration with adrenalin solution.
2. The arrows shows the nerve lesions that extend under the clavicle.
3. After the osteotomy of the clavicle all the plexus is exposed allowing a complete repair.


Once the plexus is exposed and the lesions determined, repair is done rarely by direct suture and usually with grafts.
The grafts are the sural nerves. They are taken by longitudinal incisions on the calf of both legs. These nerves are very delicate and need a complete exposure if they are to be harvested without damage. The suppression of these nerves do not induce any severe defect in the legs. Immediately after harvesting the nerve, there is a slight lost of sensation on the lateral part of the foot, which will progressively diminish with time.

The grafts are prepared on the table; cables are tailored at the exact necessary length and glued together, using biological glue.

The cable trunk is then fit into the defect and the extremities glued under the microscope. Since almost 15 years, we rarely use sutures but quite only fibrin glue. In some cases where most roots are avulsed from the spinal cord, it is necessary to use donor nerves from other parts of the plexus or extraplexual.

When the roots have been avulsed or when they are insufficient , it is still possible to expect reasonable results . This is also possible when there is partial recovery and when there is a doubt whether a complete repair may jeopardize the already recovered functions .
This will be done with the technique of nerve transfer.

Nerve Transfers

In presence of root avulsions due to the lack of proximal nerve stumps the only possibility to connect the distal part of the plexus will be through 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.
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.

Two different situations may occur: upper palsy or total palsies.

  • In avulsion of upper roots many neurotisation can be used to restore practically all the functions depending from C5 C6 /C7 roots.
    Spinal accessory nerve is sectioned distally to the branches devoted to upper trapezius in order to spare its function and sutured to suprascapular nerve to recover external rotation.

    A fascicle of ulnar or median nerve carefully selected by intraoperative electrical stimulation, is sutured to biceps m. or brachialis m. nerve branches or to both. This will allow an excellent recovery of elbow flexion. A branch of triceps muscle is sutured to the portion of axillary nerve to be possible devoted to anterior and middle deltoid. This neurotisation initially described through a posterior approach has recently changed using an anterior, axillary approach (technique described by Jaime Bertelli). The advantage of this approach is that being normally used in association with a biceps neurotisation allows to use the same anterior approach avoiding turn the patient.

    In some instances when C7 is involved in absence of a useful elbow extension, a triceps neurotisation can be done in association with neurotisation of biceps branches . In this case both median and ulnar nerve fascicles will be used. Is is undoubtful that distal neurotisations in upper roots avulsion have given a great improving in the results either in terms of shoulder function and elbow flexion. This fact induced many surgeons to avoid plexus and go straightforward to distal nerve transfers without exploring the plexus.
    Except the cases of sure avulsion of upper root we suggest to explore the plexus and then decide, depending on the circumstances, if a repair with grafts or with neurotisations is indicated. As a rule the absence of wrist extension represents clear indication to a repair of the plexus with grafts.
  • In total brachial plexus palsies with multiple root avulsions the repair with neurotisation is more limited due to the extension of the lesions. Generally even with multiple root avulsion lesions at least one or two root’s stump can be find in children; in these cases 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. But this will not be usually sufficient to restore the entire plexus especially when the remaining one or two roots are too reduced in calibre or not in good conditions. The repair of lower root to recover a function at the hand is mandatory in obstetrical palsies. If the remaining root/roots is/are of bad quality to the point we cannot trust in them, we will add to grafts repair from these roots, neurotisations from intercostals or, as we have started to do recently, with the contralateral C7 root.

    In these case we can assure with the upper root’s stumps a functional recovery of the upper arm (shoulder and elbow) dedicating to the recovery of the hand function from the neurotisation with the CC7. We must underline that neurotisation with phrenic nerve, used in adults cannot be used in little babies. The technique of contralateral C7 neurotization via the prespinal route is described in the chapter “Late repair”.

Double Neurotization of Biceps and Brachialis : A. XI to SS
B. Contralateral C7 to Lat cord
C. Triceps to Axillary
D. Lower suscap. to Axillary
E. Intercostals to Musculocutaneous
F. Ulnar to Biceps
G. Median to Brachialis

Results

What can we expect from primary surgery?

There is difficulty in the fact that surgical results can be assessed only at the end of the growth years or at least after 4 to 8 years and that currently very few teams have the long term results. The final result is a combination of the results from all of the surgeries, and, of course, the huge amount of work done during physiotherapy and at home with the child's family. Even with excellent nerve recovery, we may still obtain a poor final result, if the child does not use his extremity and rejects it. On the contrary, some very obstinate children will use a limb with limited recovery to its maximum. It is of the utmost importance for the family to understand that a passive attitude may lead to a poor functional result even with an excellent surgical recovery. However, there are a few publications that are reporting long term results and they are very encouraging. Our experience, being the longest, has enabled us to assess the results of our surgeries after several years. In order to assess the children we have developed a grading system that is now used internationally. According to this grading system the results are the following :

  • For the shoulder: At 4 years, 80% of the children have good or excellent result in C5 C6 lesions. In the C5 C6 C7 lesions, only 61% have good or excellent results. Even in complete palsy, the results after 8 years are 77% of average, good or excellent results.
  • For the elbow: Results are always good. Even with more severe, complete paralysis, 81% show good or excellent results after 8 years
  • For the hand: After complete paralysis, the results are quite encouraging. Although at 2 years, only 35% of the children have a useful hand, after 8 years and several tendon transfers, 76% of the children have a useful hand. This shows that even lower root avulsion must be repaired and that the hand recovery is a mandatory aim.

As was said previously, these results are analytical and do not always reflect the full reality. They do not take in account  the shortening of the arm, the scars, the lack of control of the limb, and all the psychological difficulties of the child.




Result after C5 - C6 repair by grafts



Result after triple nerve transfer



Result after complete repair