Evaluation of a simplified technique for nerve repair by means of entubulation by flexible controlled release glass

Abstract

The experiments presented in this thesis are a study in which the use of a biodegradable glass wrap was compared with microsurgical epineurial suturing as a means of repairing cleanly divided median nerves in a sheep model.

Twelve sheep were used in a control group and in each of four repair groups in which the following procedures were carried out:

1. Neurotmesis and repair using microsurgically placed epineurial sutures of 10/0 polyamide

2. Neurotmesis and repair by entubulation with the biodegradable glass wrap secured by 6/0 polyglactin macrosutures

3. Neurotmesis and repair by entubulation with the biodegradable glass wrap secured by fibrin (Tisseel) glue

4. Neurotmesis and repair by entubulation with the biodegradable glass wrap secured with polycaprolactone glue.

No gap was left between the proximal and distal stumps. Electrophysiological tests on the median nerve, flexor carpi radialis muscle and flexor digitorum superficialis muscle were carried out seven months after the repair and a portion of the median nerve distal to the repair site was excised for morphometric examination after all electrophysiological testing had been completed.

The main conclusions of the present study were:

1. Nerves repaired with the biodegradable glass wrap and fibrin glue displayed distal neuronal regeneration that was no different from that which occurred after a tensionless microsurgical epineurial suture. This biodegradable glass wrap, secured with fibrin (Tisseel) glue, could therefore be used in humans to repair simple nerve divisions.

2. Using the wrap in nerve repair is simple and is quicker and less expensive than microsurgical epineurial suture.

3. Nerve regeneration after nerve repair could be assessed in humans by measuring maximum conduction velocity (CVmax) (m s⁻¹) and transcutaneous stimulated jitter (TSJ) (μs)