Abstract
- The treatment goals of damage control surgery in orthopedics (DCO) include:
- Give priority to other more severe, life-threatening associated injuries.
- Improving vascular flow and subsequent tissue perfusion by reducing and realigning long bone fractures.
- Temporary stabilization of long bone fractures, definitive fixation semi-electively, when the general condition of the patient improves.
- Give priority to other more severe, life-threatening associated injuries.
General Principles
The treatment goals of damage control surgery in orthopedics (DCO) include:
Give priority to other more severe, life-threatening associated injuries.
Improving vascular flow and subsequent tissue perfusion by reducing and realigning long bone fractures.
Temporary stabilization of long bone fractures, definitive fixation semi-electively, when the general condition of the patient improves.
Special Equipment
Damage control surgery in orthopedics is centered around the placement of external fixators for long bone fractures and selected pelvic fractures. Placement of this hardware requires a set of specialized tools, generally available in any facility that treats patients with orthopedic injuries.
Instrument trays are manufactured by several different companies, but all will share similar components.
Pins – Placed into the cortex of the bone as the anchor point for the external fixator.
Pin Clamps – Secured around two pins, providing the bridge between the pins and the connecting rods. Each pin clamp can be affixed with two posts (straight, 30°, 90°) and can be rotated into 12 different positions, thus giving maximal flexibility to the structure of the external fixator.
Pin to Rod Coupler – Can connect a pin to a connecting rod, when a pin clamp is not used.
Rod to Rod Coupler – Can connect a connecting rod to a post or another connecting rod.
Drill – Can be either pneumatic-driven or battery powered.
For pin selection, the choice is between a blunt and a self-drilling pin. Blunt pins require pre-drilling of holes in the cortex. Self-drilling pins can be mounted directly onto the drill and drilled into place.
Another screw that may be necessary is a centrally threaded pin. This long pin has a self-drilling tip, but the threads are located in the middle of the pin, not at the end. This pin is placed across the calcaneus, when an ankle-bridging external fixator must be placed.
Positioning of Patient
Placement of external fixators on the lower extremities requires the patient to be in the supine position with the legs in a neutral position.
Management of Specific Fractures
Mid-Shaft Tibia Fracture
After the decision has been made to stabilize a tibial fracture with an external fixator, the locations of the anchoring pins must be decided. Two pins should be placed on each side of a fracture site. One is inadequate to provide stability.
When choosing a location, the pin closest to the fracture site must be greater than 2 cm away. Pin placement too close to the fracture could prevent adequate stabilization.
Care must be taken to avoid placing a pin in the metaphysis or intra-articular.
If the fracture is very proximal or distal and there isn’t adequate tibial shaft to place pins, an articular-spanning fixator must be placed (see below). The safest area to place pins into the tibia is anywhere between the anterior tibial ridge to 60° medially.
Figure 45.3 Pin site placement in relation to the fracture. Safe placement is along the anterior aspect of the tibia, with pins placed >2 cm from fracture. Avoid the metaphysis.
Make a 4 mm incision over the pin sites with a scalpel and carry down through the periosteum. With the self-drilling pin loaded on the drill, place the tip of the pin directly on the cortex. Apply partial power to the drill until the pin adequately engages. Then, increase power on the drill. After the tip of the pin passes through the first layer of cortex and into the medulla, there will be decreased resistance. As the tip engages to far cortex, the resistance will increase again. Be sure to allow for several more revolutions of the pin to be sure that there is secure bicortical purchase. Without bicortical purchase, the pins can come loose and the external fixator can fail to adequately hold reduction.
Repeat the above process with the second pin. When judging how far to place the second pin from the first, use a 5- or 10-hole pin clamp as your guide. You should place the pins as far apart as possible, but still be able to fit into one clamp. The second pin should be placed parallel to the first.
Repeat the above process with the distal pins.
Figure 45.4
(a) Drilling the pin into the tibia. It is important that the pin has a bicortical purchase for maximum stability.
(b) Placement of the second pin. The pin should be placed roughly parallel to the first, with the largest gap allowed between pins to be placed within the pin clamp.
