Interfascicular suture with nerve autografts for median, ulnar and radial nerve lesions

Interfascicular nerve suture with autografts is the operation of choice for repairing peripheral nerve injuries because it ensures more precise alignment of the fasciculi and so better chances of reinnervation of the sectioned nerve. The procedure as described by Millesi et al has been used at the Istituto Neurologico di Milano in 30 patients with traumatic lesions of the median, ulnar and radial nerves. All have been followed up for 2 to 7 years since operation. The results obtained are compared with those of other series obtained with interfascicular suture and with epineural suture. Microsurgery is essential. The best time to operate is discussed.

Cross-face nerve grafting in facial paralysis

Facial paralysis causes a most disturbing deformity with functional, emotional and social consequences for the people afflicted. Since a few years most promising advances in the treatment of facial palsy have been developed and new ways of surgical management have been introduced. Cross-face nerve grafting connects the non-paralysed facial nerve branches to the paralyzed ones and by these means realizes a reanimation of the paralyzed side of the face. Fourteen cases have been operated according to this technique. The results of 10 cases with a sufficient follow-up are analysed. Good and satisfactory results were obtained in 8 cases. Two cases were considered bad with poor recovery of facial muscle activity. The overall results of cross-face nerve grafting are very gratifying. The technique should always be attempted in first instance. Other substitutional methods for further improvement should be reserved for later.

Suppression of sprouted synapses in axolotl muscle by transplanted foreign nerves

1. The supracoracoideus (s.c.) muscle of the axolotl shoulder is innervated by two nerves, the anterior and posterior s.c. nerves. The posterior nerve was induced to make synapses outside its normal territory in the muscle by removing a segment of the anterior nerve. Intracellular recording indicated that the efficacy of transmission from posterior nerve terminals outside their normal territory increased over several weeks prior to the return of the anterior nerve. 2. The anterior nerve reinnervated its muscle by 40-50 days after the operation, and quickly made synapses throughout the muscle. The posterior nerve territory subsequently returned to its original size and location over 3-6 months. 3. Transplantation of either of two completely foreign nerves into s.c. muscles with enlarged posterior nerve territories resulted in a similar return of the posterior nerve territory to its normal size when anterior nerve regeneration was prevented. 4. These results suggest that the advantage which newly regenerated native nerves have over sprouted foreign nerves is not the quality of 'nativeness' but rather the smaller number of synapses they support. In this view, sprouted nerves compete less effectively because they initially support more synapses per neurone than regenerating nerves.

The results of nerve grafting in the wrist and hand

To evaluate the usefulness of nerve grafting we studied 38 patients having 11 median, 7 ulnar, and 33 digital nerve grafts. Group funicular (interfascicular) grafting using magnification was performed in all patients. We followed 12 patients with 8 median and 5 ulnar nerve grafts for at least one year and 18 patients with 27 digital nerve grafts for at least six months. Medical Research Council criteria were used for evaluation of nerve function. Results in our patients and in previously reported patients having nerve grafting or repair were compared. Sensory function following ulnar nerve grafting was significantly better than that following nerve repair. Sensory function following median and digital nerve grafting was as good as that following nerve repair. Motor function following ulnar nerve grafting was as good as that following nerve repair. Previously reported patients having median nerve repairs or grafts had significantly better motor function than our patients.

Neurorrhaphy after loss of a nerve segment: comparison of epineurial suture under tension versus multiple nerve grafts

Epineural neurorrhaphy under tension and interfascicular grafting, two methods of bridging gaps associated with loss of a nerve segment, were compared. After resection of a 2 cm length of both ulnar nerves in cats, one nerve was sutured under tension using an epineurial technique, and the other was repaired using multiple interfascicular sural nerve grafts. Six months later return of nerve function was evaluated. Subjective evaluation included ambulation, sensation, and intrinsic function. Objective measurements included muscle efficiency, maximum strength, muscle weights, and total axon counts. No statistical difference was observed between these two techniques. Histochemically, there was marked fiber type grouping of the reinnervated muscles for both types of repairs. Histologically, perineurial fibrosis and axonal disorganization were equal for both techniques, but significantly greater suture granuloma formation occurred in the nerve repaired under tension. Individual grafts retained their identity and remained distinct grossly and microscopically.

Median and ulnar nerve transections treated with microsurgical interfascicular cable grafting with autogenous sural nerve

Interfascicular nerve grafting was used in 37 median and 26 ulnar nerves, all completely transected. In a follow-up period of 2.5 to 5 years, useful motor recovery (M3 or higher) was achieved in 84% of median nerve lesions; in ulnar nerve lesions, useful motor recovery (M2+ or higher) was achieved in 73%. Sensory recovery with some return of two-point discrimination sense was found in 63% of low median and 50% of low ulnar nerve lesions. In the median nerve group, results for patients younger than 20 years of age were significantly better than in older patients. Neurophysiological investigations gave evidence for nerve regrowth through the grafts in all but one patient, although the loss of axons was probably considerable if the amplitudes of sensory potentials were used as a parameter. Grafts of 2.5 to 5 cm in length gave better results than longer grafts, and results for the distal median nerve lesions were superior to those for the distal ulnar nerve lesions. Use of interfascicular nerve grafting techniques for nerve gaps greater than 2.5 cm is recommended.

Peripheral nerve injuries: studies in higher nonhuman primates

Two skeletally mature baboons underwent comparative neurorrhapies following transsection of both ulnar nerves without loss of nerve tissue. In baboon 1 there was no difference in objective evaluations at 12 months when an epineurial neurorrhaphy was compared to a perineurial fascicular neurorrhaphy. In baboon 2, the one that had interfacicular grafts in one upper extremity and an epineurial neurorrhaphy on the other side, there was significantly better functional return on the epineurial side than one the graft side. Grass and histological evaluation showed that the grafts retained their integrity and regenerating axons transversed the grafts well.

Cross-facial nerve grafts and microneurovascular free muscle transfer for long established facial palsy

Cross-facial nerve grafts followed in 4 to 12 months by microneurovascular free gracilis transplantation can produce adequate reconstruction in the lower two-thirds of a paralysed face. The mixed sensory and motor deep peroneal nerve and the small muscle bulk of the extensor digitorum brevis limit its usefulness in facial palsy. The gracilis has proved to be a much superior muscle. A feasible method for total reamination of unilateral facial palsy is presented.

Histological studies of experimental interfascicular graft repairs

Biopsies of sutured and grafted primate peripheral nerves were examined by light and electron microscopy after the final set of electrical measurements had been recorded. Inspection of all proximal stumps showed the expected regenerative activity which was not affected by the nature of the nerve repair. Transverse sections through the epineurial, interfascicular, and graft suture lines showed a similar pattern in all animals and at this site nerves sutured by epineurial technique could only be distinguished from those sutured by fascicular technique by loci of the non-absorbable suture. Fascicular repairs, whether done fascicle-to-fascicle or with interposition of grafts, had a more lengthy neuroma than did the epineurial repairs. Maintenance of fascicular architecture through the course of the grafts was variable. Fascicular structure was frequently absent in the central graft segments and in segments close to the second suture site. The method of repair used more proximally could not be distinguished by evaluation of distal stump segments. Measurements of myelinated fiber size made of distal stump axons revealed no statistical difference between the methods of repair.

Extratemporal facial nerve grafting and radiotherapy

Nineteen patients with extratemporal facial nerve grafting procedures and 13 patients with facial hypoglossal anastomosis were followed up with serial photographs for at least one year. The photographic analysis of the results demonstrates that radiotherapy had a detrimental influence on the return of facial movements after extratemporal facial nerve grafting.

Cross-face nerve transplant

The two stage principle is one of the most important features of the procedure. It allows starting the operation at a very early stage (one to six months). The donor area in the periphery is very well supplied, therefore as many facial fascicles as necessary can be sacrificed on the healthy side. We have never noticed any functional disturbances. The nerves leading to the buccinator muscle and those which innervate the lateral pull of the mouth are especially suitable. This weakening of the strong pull of the mouth is of great value for symmetry but unfortunately relapse to the original state is common. The selection of the nerve fascicles on the healthy side must be executed in a deep layer below the muscles because all large branches are located here. The end of the sural grafts should positioned far back on the paralyzed side to enable easy anastomoses at the second stage. A face lift incision on the paralyzed side and tightening of the skin are of additional value and provide some support to the elongated muscles. The combination of cross-face nerve transplant with other substitutional methods in which muscles are used for reinnervation is very promising. In our experience physiotherapy is a very important measure. It should be started after the onset of the palsy and continued until restoration of the face is complete. It is usually applied three times a week with exponential current and at a strength of 20 to 60 milliamperes. Each group of muscles receives a 2 to 3 minutes dosage. It is helpful if the patient can use a stimulation apparatus at home daily for short treatments.

Neurophysiological studies of autogenous sural nerve grafts

Sixteen autogenous sural nerve grafts used for ulnar and median injuries in the forearm have been studied neurophysiologically up to two and a half years after operation. Motor and sensory nerve conduction studies revealed a slow but sustained improvement during the follow-up period. By two years, motor conduction velocity across the graft itself reached in most cases 40 to 85% of the conduction velocity in the contralateral normal limb. Some reduction of motor conduction velocity was observed in the uninjured nerve proximal to the graft but this was less marked. Sensory nerve action potentials were obtained in 44% of nerves after 18 months although in all cases the amplitude of the potentials and in most cases their velocity, was greatly reduced.

Nerve grafting

By avoiding tension and securing anatomical neurorrhaphy, regeneration of nerve is obtainable. When the gap exceeds a certain limit, the only way to avoid tension is the use of grafts. Experience in animal experiments and clinical practice has demonstrated that regenerating axons can cross 2 optimal suture lines much more easily than one sub-standard one. For bridging a gap autografts are used, because in autografts the fascicular pattern is preserved and its Swann cells survive. With the interfascicular technique the dissection of the nerve stumps proceeds from normal to abnormal tissues and the epineurium is resected. The coaptation must be exact so that the grafts cover the whole cross sectional area of the fascicle. All this can be achieved by the use of one 10--0 or 11--0 nylon suture. The clinical results show that in the median nerve 82%, in the ulnar 80% and in the radial nerve 92% of good functional results can be obtained. Also in brachial plexus injuries the interfascicular nerve grafting procedure opened new ways. Therefore interfascicular nerve grafting, using autografts in cases of nerve repair, where a gap may occur, currently is the method of choice.

Surgical treatment of traction injuries of the brachial plexus

A series of 508 patients with traction injuries of the brachial plexus (birth trauma excluded) has been investigated over a period of 11 years. Severe cases with root avulsions, ruptures of nervous pathways or severe disorganization of funiculi do not heal spontaneously or heal poorly. Whether these patients can benefit from modern microsurgical techniques (neurolyses, autologous nerve grafts and neurotizations with intercostal or other nerves) is presently under investigation. Operations were performed on 164 patients of whom 114 had root avulsions and 16 had 2 level injuries. Surgical treatment was planned according to the severity of the lesion. In about 10% no reconstruction was possible, or was of doubtful value. There is a striking difference in results of supraclavicular and distal, infraclavicular lesions. Only 55% positive of 58 patients of the first group were improved while 85% of 20 patients of the second group were benefited to some extent. None of the patients belonging to the first or second group recovered hand intrinsic function if pathways coming from C8 and T1 were injures. None recovered tactile gnosis. The effect on pain was sometimes ameliorative, but generally unpredictable.

Cross-face nerve transplantation in facial palsy

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Anastomosis between the two facial nerves

A case of traumatic facial palsy incurred during the removal of an acoustic neuroma via a sub-occipital craniectomy is presented. The palsy was rehabilitated to a satisfactory degree by anastomosing the normal to the paralyzed facial nerve using an autoplastic peripheral nerve graft of suitable length to join the two.