Wrist fractures--more specifically, distal radius fractures--occur when the distal end of the radius, or the end closest to the wrist, is subjected to forces typically from a fall onto the outstretched hand and wrist. Data from the National Osteoporosis Risk Assessment showed that 170,000 women were studied over a three-year period and that 4.2, or 1.4 percent, of every 1,000 women in the 50 to 59 age group suffered a fracture, with wrist fractures being the most common type. Treatments for wrist fractures vary and are determined by the type and severity of the injury.
Splinting
Splints are supportive devices used to immobilize and protect a wrist fracture. They're typically thought of as half-casts, or partial casts, in that they don't completely cover or provide circumferential immobilization to an extremity. Splints can be made of virtually any material--cardboard, wood or metal, plaster, fiberglass or fabric combinations. Splints are designed mainly to offer protection and immobilization while being removable. Plaster and fiberglass splints are typically applied using an elastic bandage; commercially made splints offer Velcro strap closures and may be adjustable.
Casting
A cast is a circumferential immobilization device used to treat wrist fractures. Casts are typically applied over a cotton wrap base and applied using rolls of the desired material. Most cast rolls are of either plaster or fiberglass material, and are activated by immersing the roll in water. Casts provide a rigid, comprehensive and cylindrical mode of protection, and can be molded to form-fit the shape of the forearm as well as allow for hardening with the extremity in a pre-determined position. Casts are often used for long-term wear, as well as for more difficult fracture treatment. Casts provide optimal external protection from bumping the injured extremity. Patients with casts are educated to look for signs of pressure areas against bony prominences of the wrist as well as the skin, and for signs of cast loosening and breakdown.
Reduction
The term reduction, refers to the act of setting a fractured bone. When reducing a fracture, the bone fragments are manipulated manually until they are in an acceptable, anatomic position and alignment. Reduction of a fracture is typically accomplished by one of two methods: closed reduction, in which the bone/fragments are set without opening the skin; and open reduction, in which the skin and tissues are opened and the bone fragments are reduced under direct vision.
Closed reduction is performed on fractures that are typically not in need of any formal fixation, such as screws and plates. However, this method is frequently used in combination with insertion of pins through the skin for additional fixation. This is called a closed reduction with percutaneous, or through the skin, pin fixation. Open reduction is almost always used in conjunction with some additional means of fixation, such as plates and screws or pins.
Pin Fixation
Pin fixation involves the use of sterile, stainless steel pins that are drilled into the bone fragments and across fracture lines to achieve fixation. Use of these pins is mostly a temporary measure, and they are usually removed between four to six weeks after the injury, when sufficient healing has taken place. Pins come in smooth and threaded varieties, and are chosen based upon fracture type and type of fixation required. After insertion, which is performed under sterile technique in an operating room, pins may be cut off just under the skin or left prominent outside the skin and covered with some form of cap.
Plating
Plate fixation refers to the use of specially designed metallic plates that are positioned directly over a fracture and secured with multiple screw insertion. This is done under open surgical exposure. Plates are rarely removed after surgery and are designed to be permanent. They come in a wide variety of shapes and sizes to fit almost any fracture need. The use of plates and screws often allows for less restrictive external support. In many cases, patients are placed into splints or bulky dressings instead of casts due to the exceptional holding power of the internal plates.
External Fixation
In some instances, wrist fractures may be extremely comminuted, or broken into many pieces, so that reduction by any of the above means would be inadequate to achieve optimum position and alignment. Devices called external fixators are used to immobilize the wrist without violating the skin or deep tissues. Pins are inserted into the second metacarpal, or bone of the hand, and also into the radius, or forearm bone. These pins are then connected to each other by way of adjustable clamps and the fracture is bridged with a long rod--typically made of a material, such as carbon fiber--that allows X-ray beams to pass through for visualization of the fracture during healing. Clamps on an external fixator are adjustable in all directions, allowing for external fine-tuning of position and alignment during the early healing phase if necessary.
References
- Women toWomen: How Common are Wrist Fractures?
- Lucile Packard Children's Hospital: Cast Types and Maintenance
- Wheeless Online: External Fixators for Distal Radius Fractures
- Miami Hand Center: Volar Plate Fixation of Distal Radius Fractures
- Pub Med Central: Treatment of Distal Radius Fractures with Percutaneous Pinning
