The successful application of an Ilizarov-type circular fixator—or any external skeletal fixation system, for that matter—demands meticulous wire and pin insertion techniques. The objectives for both types of implants are the same:
• Avoid tissue necrosis during insertion, whether due to tension on the skin or wrapping up of fascia or other limb structures around the implant.
• Avoid impalement of nerves, vessels or tendons. Use a cross-section atlas as a guide to safe pin insertion.
• Transfix muscles at their maximum length by proper positioning of the limb at the time of wire or pin insertion. Flex the adjacent joints during extensor muscle transfixion and extend these joints as a pin or wire passes through flexor muscle groups.
• Prevent thermal injury to bone during insertion, the cause of chronic pin tract osteomyelitis.
A slow stop—start drilling technique, irrigation during insertion, and avoidance of intracortical (rather than transmedullary) placement are the basic measures. Any drillbit or wire tip emerging with blackened bone has burned the osseous tissue around the hole; the site must be changed.
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