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Physiological properties (tetanic tension, single twitch, fatigability) of free autologous muscle transplants in cats were examined in vivo five months after transplantation. After 2 weeks denervation the peroneus longus muscle was placed isometrically in the abdomen with the omentum around the muscle and with the proximal end of a cut branch of the femoral nerve attached to the muscle. (In one case a sensory nerve was used.) Five months after transplantation the function of the muscle was controlled in vivo by nerve stimulation. In the case when a sensory nerve was connected to the muscle no contraction was obtained upon indirect or direct stimulation. All the other muscles contracted when the nerve was stimulated. The mean maximum tetanic tension was 16% of the mean for the control. The twitch-time was about the same as in the control muscle but the contraction time was longer and the half relaxation time shorter compared with the control. The transplanted muscles fatigued more slowly than the normal peroneus longus muscles. In spite of the unphysiological placement of the muscles in the abdomen where they have no natural function to fulfil, they became reinnervated and contracted as late as five months after transplantation.

Free autologous transplants of previously denervated whole muscles in adult cats were studied with histochemical and electromyographical methods. The transplants were placed in contact with normal intercostal muscles in intercostal spaces and removed at intervals from 5 days to 44 weeks after transplantation. Normal muscles as well as transplanted muscles without previous denervation and muscles denervated and left in situ were also studied.. The fibres of the previously denervated grafts survived the first avascular period, but a de-differentiation of enzymatic characteristics of the red and white fibres occurred and endured during the first 6 weeks after grafting. The first signs of reinnervation could be identified with electromyography after 4 weeks and with histochemical techniques after 6. Reinnervation of most of the fibres of the transplants was completed about 14-18 weeks after grafting. No fibrillations were then found electromyographically and in the histochemical preparations most fibres had attained near-normal staining characteristics. Type grouping was apparent but less pronounced than reported after reinnervation through the motor nerve. There was conclusive evidence that previously denervated muscles survived transplantation and became structurally and enzymatically mature whereas muscles transplanted without previous denervation undergo extensive fibrotic changes.

After 2 weeks of denervation, whole leg muscles of adult cats were transplanted to intercostal spaces and removed at intervals from 5 days to 44 weeks after grafting. The connective tissue formation and capillary supply of the grafts were studied histologically and histochemically for connective tissue and ATPase. In addition, normal muscles, denervated muscles left in situ, and muscles transplanted without previous denervation were studied. During the denervation period of 2 weeks the capillary network increased slightly. During the first 6 weeks after grafting only a few, thick-walled, irregularly shaped capillaries were present in the grafts. At 8-12 weeks there was a pronounced increase in the vascular supply, coincident with reinnervation of the grafts, and after 40 weeks the capillary pattern appeared fairly normal. In the early stages a marked increase in perimysial and endomysial connective tissue took place. With increasing reinnervation a gradual disappearance of the endomysial connective tissue occurred and in the most mature grafts a minimal increase of perimysial connective tissue remained. In muscles transplanted without previous denervation, extensive fibrotic changes developed.

To compare the healing time of standardized wounds partly covered with autologous patch skin grafts, and wounds totally covered with a combination of allografts and autologous patch grafts 10 rabbits, each with two standardized wounds, were used. On each rabbit one wound was partially transplanted with 6 autologous patch grafts 9 mm in diameter. The patches covered 6% of the wound area. The second wound was covered with a rabbit skin allograft with six holes 7 mm in diameter. In these holes 6 autologous patch grafts, 9 mm in diameter were placed (intermingled transplantation of auto- and allografts). The average healing time for the ten wounds treated with autografts only was 39.8 days and for the wounds covered with auto- and allografts 21.6 days. This shows that the same amount of autologous skin epithelialized a wound area about 17 times larger than itself nearly twice as fast if the wound surface between the autografts was covered with allografts than if it was protected by a dressing only.

End-plate formation in free autologous transplants of previously denervated whole muscles in adult cats were studied with a histochemical technique for cholinesterase. Grafts from 5 to 40 weeks old have been examined. The original end-plates degenerated and could not be seen in transplants older than 9 weeks. New, immature end-plates formed at many sites in the transplants. They were seen as early as 5 weeks after transplantation. They progressively increased in number during the first 12 weeks. In the oldest transplants the end-plates were relatively mature and appeared in clusters or were scattered.

For reanimation of the cheek in 8 young patients with long-standing facial palsy a method with cross-face nerve grafting followed by free muscle transplantation has been used. The sural nerve was used as nerve graft and placed in a subcutaneous tunnel across the face. In the normal cheek 3-4 fascicles of the nerve were anastomosed to facial nerve branches innervating muscles elevating the angle of the mouth. Four to 13 months later the extensor digitorum brevis muscle to the second toe or the palmaris longus was transplanted to the paralysed cheek. It was attached between the zygomatic arch and the angle of the mouth. The end of the nerve was sutured to the muscle after taking a biopsy. The follow-up period has been 7-30 months. At 7 months 6 patients had positive EMG, either on voluntary movement or on stimulation of the contralateral facial nerve. Three of them had also a slight movement in the cheek. Two patients are as yet only 7 months postoperative. In the remaining two cases, No. 2 and 4, there were no signs of reinnervation. At 18 months 4 out of 6 patients had a synchronous natural contraction in the cheek giving increased balance to the mouth. These patients had a positive EMG. In patients No. 2 and 4 there was neither innervation nor improvement. At 30 months there was additional improvement in two cases but as previously in patients No. 2 and 4 there was neither improvement nor signs of innervation of the muscle on the EMG. The other 4 patients have not reached this postoperative stage.(ABSTRACT TRUNCATED AT 250 WORDS)