A technique for repair of peripheral nerves with the argon laser was
evaluated with regard to functional and histological recovery. The results
were compared with those of reconstruction by a microsurgical
epineurial-suture technique. The terminal branch of the peroneal nerve to
the extensor digitorum longus in thirty-three New Zealand White rabbits
served as the experimental model. Histology and neuromuscular function were
evaluated at one, two, and six months after repair. When the diameters of
the axons and the morphology distal to the site of repair were evaluated,
the nerves that had been repaired with the laser more closely resembled
those of the control rabbits. Examination of the site of repair also
revealed less foreign-body reaction and axonal outgrowth in the
laser-repaired nerves than in those that had been reconstructed with
epineurial suture. Neuromuscular function was evaluated by measurement of
the force of contraction of the extensor digitorum longus after electrical
stimulation of the nerve proximal to the site of repair. Functional
recovery paralleled the histological findings. At one month, there was no
difference in the neuromuscular function that had been achieved with either
technique. At two months, the laser-repaired nerves began to show increased
muscular strength at higher frequencies of stimulation (sixteen and
thirty-two hertz). Six months postoperatively, the nerves that had been
repaired with the laser had consistently better neuromuscular function than
those that had been repaired by epineurial suture. The improvement was most
marked at higher voltages of stimulation (threshold multiplied by ten) and
at frequencies of stimulation of more than sixteen hertz.