The Effect of Distraction Osteogenesis on Peripheral Nerve Regeneration in Rats: A Preliminary Study In Vivo

Figure 4

Transmission electron microscopy results of the sciatic nerves in different groups (n = 2 per group). In the Control, closely arranged lamellar myelin structures (red arrows) were observed with the axonal membrane being smooth and intact containing microtubule microfilaments. At Group 0-week, the myelin lamellae of myelinated nerve fibres were loosely sheeted apart (yellow arrows), with oedema of Schwann cells, vacuolar myelin degeneration, and even compression of axons also visible. Mild reparative changes and new myelination occurred in Group 2-week (yellow arrows). Active proliferation of Schwann cells was identified in Group 4-week, although degenerated nerve fibres were still present (yellow arrows). At Group 6-week and Group 8-week, the arrangement of nerve fibres gradually returned to normal (yellow arrow), with a large number of newly formed myelin sheaths observed and occasionally with myelosphere changes in myelinated nerve fibres (red arrows).