Kirschner Wire

wire pin bone
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A Kirschner wire (also called a K-wire) is a thin wire or pin that can be used to stabilize bone fragments. These wires can be drilled through the bone to hold the fragments in place. They can be placed percutaneously (through the skin), or can be buried beneath the skin.

K-wires come in different sizes, and as they increase in size, they become less flexible.  K-wires are often used to stabilize a broken bone, and then removed in the office once the fracture has healed.

  The wires can also be threaded to help prevent movement or backing out of the wire, although that can also make them more difficult to remove.

K-wirse used to be used more commonly when traction was a common treatment for certain types of fractures.  When traction is used, a K-wire is often inserted into a bone to provide a rigid anchor to the bone, and then weight is pulled on the bone (through the wire) to pull the broken extremity into alignment.

Problems With Pins

There are possible complications associated with the use of K-wires:

  • Infection: The location of pin insertion can be a source for infection to enter the body.  If left through the skin, bacteria can travel along the pin tract and get deeper into the body, and possibly to the bone.  For this reason, patients with K-wires that are left exposed are typically instructed on techniques for pin care to prevent infection.
  • Breakage: Pins can provide stable fixation of a fracture, but most pins are relatively thin in diameter and they can break if there is insufficient fixation to support the broken bone.
  • Fracture Movement: K-wires generally provide less rigid fixation of fractures than some other techniques such as plates and screws, and metal rods.  Therefore, it is sometimes possible for the fracture to shift its position when only K-wires are used for fixation.
  • Migration: One of the most concerning complications is pin migration.  For this reason, extreme care must be used especially when using K-wires in the chest or abdominal area.  There are case reports of placing K-wires in bones around the shoulder only to find them migrating into the chest cavity weeks or months later.

    Pin Removal

    Most often, K-wires are removed sometime after the bone has healed sufficiently.  There are exceptions if the wire is buried deep inside a bone, but the majority of the pins are removed once healing is complete (or at least to a point where the broken bone is stable).  The smooth pins can often be removed in the office without special anesthesia.  Pin removal should not cause too much discomfort for most patients.  However, pins that are under the skin, threaded K-wires, or pins that are otherwise difficult to remove may have to come out in an operating room under and anesthetic.

    Also Known As: K-Wire

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