So far surgeons have used tissue expansion exclusively to attain coverage of skin defects. Most previous studies involving expanders investigated changes in cutaneous tissues and blood vessels. Frequently we encounter in the process of insertion of tissue expander that major nerves and vessels lie just above either beneath of it. Up to date, there is seldom reports concerning its effects of long-term compression on the nerve trunk. This has led us to investigate whether tissue expander can be applied to locate adjacent to major nerve trunk without damaging its function and integrity.
50cc rectangular silicone tissue expanders (McGhan) were implanted under the gluteal muscles right above sciatic nerve of the thigh of 20 4kg. white rabbits. After 4, 8 and 12 weeks of full expansion, sciatic nerve functions were investigated by nerve conduction velocity and amplitute study and animals were sacrificed, obtained sections of sciatic nerve to clarify the possible pathologic changes.
Results of the experiments were as followings;
1. Nerve conduction velocity was 74.8 ± 13.8 m/sec in control group, 65.8 ± 4.7 in 4 weeks group, 68.8 ± 6.2 in 8 weeks group, 73.4 ± 10.1 12 weeks group respectively, but without significant statistics.
2. Amplitude was 9.50 ± 1.50 my in control group, 8.20 ± 2.17 in 4 weeks group, 8.80 ± 1.92 in 8 weeks group, 9.00 ± 1.58 in 12 weeks group, but without significant statistics.
3. Focal segmental demyelination and secondary axonal degeneration were observed
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