Percutaneous pinning is a technique used by orthopedic surgeons for the stabilisation of unstable fractures.

Many fractures can be manipulated into wholly satisfactory positions, immobilized in an appropriate cast

Orthopedic cast

An orthopedic cast, body cast or surgical cast, is a shell, frequently made from plaster, encasing a limb to hold a broken bone in place until healing is confirmed...

 and allowed to heal. Some fractures, however, cannot be held in a satisfactory position by this method, and require some additional form of fixation. This is the usual situation with all displaced fractures of the first metacarpal and of the proximal phalanges of the hand, and of about two thirds of fractures of the distal end of the radius.

Pinning involves the manipulation, with X-ray guidance, of the fracture into an acceptable position, and the immediate insertion of metal pins, called Kirschner wire

Kirschner wire

Kirschner wires or K-wires or pins are sterilized, sharpened, smooth stainless steel pins. Introduced in 1909 by Martin Kirschner, the wires are now widely used in orthopaedics and other types of medical and veterinary surgery. They come in different sizes and are used to hold bone fragments...

s, through the skin, into one bone fragment and across the fracture line into the other bone fragment. These pins are normally left in position for some four to six weeks, and are removed when the fracture has healed.