Orthopedic Considerations of the Polytrauma Patient

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Orthopedic Considerations of the Polytrauma Patient

Management of lower-extremity fractures & dislocations

Orthopedic injuries comprise a large portion of emergency response requests to EMS agencies. Having a complete understanding of how these injuries present is critical for appropriate and timely management. The purpose of this article is to highlight important aspects of the prehospital assessment and management of fractures and dislocations in the lower extremities.

Obtaining a thorough understanding of the incident’s circumstances and mechanism of injury is critical. Care for the injured patient starts with a complete history and physical examination. The assessment must include a primary trauma survey to ensure all life-threatening concerns are immediately identified and managed. Any active hemorrhage from an extremity must also be dealt with.

Once the primary trauma survey is complete and any significant hemorrhage or airway concerns are addressed, a secondary survey is started at the head and continued to the neck, thorax, abdomen and pelvis prior to examining the extremities. Focusing only on an isolated orthopedic injury may allow other problems to be overlooked. For example, pain from deformed limbs can often distract caregivers from internal organ damage and hemorrhage.

Wounds & Fractures
Inspection is the first part of an extremity examination. Expose the entire length of the affected limb to enable a complete eval‎uation of the skin’s integrity. Identification of bruising and areas of redness should raise clinical suspicion for fractures. You should also identify and make note of any abrasions or lacerations in the skin, as this could indicate an open fracture. (See Figure 1.)

In high-energy trauma, open wounds may be the result of a broken bone fragment that punctured the skin (see Figure 2, p. 52) or of penetration by an outside object into an extremity. (See Figure 3a and 3b, p. 52.) These breaches in the skin provide an opportunity for environmental bacteria and foreign material to enter the body, which increases the risk of infection and orthopedic infections involving bone and soft tissue. This can lead to loss of function and possible permanent disability, and therefore all open wounds should be treated with sterile dressings.

Fractures aren’t only injuries to bones, but also to the surrounding soft tissue structures that provide valuable protection and nutrition to the involved bones. During assessment and care of orthopedic injuries, providers must be aware that when the bone continuity is broken, other vital structures such as nerves and blood vessels are at risk for injury. For example, a patient may lose a significant percentage of their blood volume if the femoral vessels are lacerated in association with a femur fracture. Therefore, assessing for adequate perfusion to the entire length of a limb is a vital part of the extremity examination.

Test for any neurovascular injury by assessing the patient’s distal pulses along with their ability to sense touch throughout the affected limb. You can also determine circulatory delays or impairment by lightly grasping an area of the extremity and watching how fast the compressed area refills with blood—much like when checking circulatory status with capillary refill.

In displaced fractures with shifted and angulated bone fragments, as well as with dislocations, understanding the pre- and post-splinting status is necessary to not further exacerbate any deficiencies. If a limb is misaligned, manipulation should be performed to position the extremity into its anatomic alignment prior to splinting. However, the maneuver should be stopped if you meet resistance. If you meet resistance and the extremity can’t be positioned appropriately, yet there’s still adequate circulation, the deformity should be splinted as positioned because a forced reduction may cause more harm.

While manipulating any injured bone, appropriate care should be taken not to break the skin’s surface. All motions should be slow and deliberate, and appropriate padding used against all bony prominences to ensure proper splinting and patient comfort, especially in the pediatric and elderly populations, where the skin is more fragile.

Injured limbs should always be placed in an appropriate splint unless a threat to life exists that requires rapid transport without it. Board splints, malleable splints and articulating splints—the latter of which allows you to adjust the length and angle to fit the deformity—should be applied so that they immobilize the joint above and below the suspected injury site. Doing so eliminates motion at the fracture site, prevents further trauma to the injury site and allows the soft tissues surrounding the break to relax. By limiting the motion of two bone ends and reducing the tension of the muscular deforming forces, pain should be significantly reduced or may even subside completely.

Dislocations
Joint dislocations occur when there’s complete displacement of the bone from its normal joint position; this results in a noticeable deformity. Several EMS texts now include the procedures for reducing unstable dislocations that present with neurovascular compromise—something not emphasized in early EMS textbooks.

The knee joint is often injured in high-speed motor vehicle crashes as well as falls from a significant height. As a joint, the articulating bones of the knee consist of the femur, tibia and patella. The joint complex has various ligaments and cartilaginous structures within it.

During a knee dislocation, connecting ligaments between the femur and tibia are torn. (See Figure 4a and 4b.) Injury to these stabilizing ligaments puts the neurovascular structures that traverse the knee at risk as well. Without stabilizing restraints, which normally restrict certain motion, the knee is capable of moving through all extremes, ultimately tethering blood vessels and nerves. Therefore, knee dislocations can be extremely dangerous and require rapid stabilization.

Splints for dislocated knees are easy to apply, but are often not utilized or applied properly because some EMS crews get intimidated by the grotesque appearance of the knee or are unfamiliar with ways to properly immobilize it.

Special Focus
Discussion of the popliteal artery as well as the peroneal nerve, unfortunately, is not covered well, if at all, in most EMT or paramedic textbooks or training programs. However, prehospital mismanagement of a knee injury may result in significant morbidity. Such clinical manifestations include a dropped foot or sensory loss to the foot because of a peroneal nerve injury along with vascular insufficiency or complete limb ischemia due to a popliteal artery injury.

Popliteal artery: The popliteal artery is the major blood vessel traversing the back of the knee. It’s a continuation of the femoral artery and serves as the feeder vessel for the geniculate arteries, which supply nutrients to structures within the knee. The popliteal artery courses through the popliteal fossa and is less mobile, due to its anatomic restraints, than blood vessels in other joints. Therefore, a dislocation—or excessive handling by an EMS crew after an injury has occurred—can easily injure it.

Peroneal nerve: The peroneal nerve originates from the sciatic nerve in the posterior aspect of the upper leg and travels around the fibula bone at the fibular neck, just below the knee, on its way to the foot. The peroneal nerve supplies sensation to the lower leg and motor function to the foot and toes.

It’s subject to injury due to its superficial location and proximity to bone. Any major alteration to the knee joint’s alignment or bony continuity of the proximal fibula places the peroneal nerve at risk. Injury to the peroneal nerve may be in the form of a stretch or complete disruption. This will potentially lead to weakness or complete loss of motor function of the foot.

Drop foot: A peroneal nerve dysfunction may occur when the nerve becomes compressed, entrapped, stretched or lacerated and is characterized by loss of movement or sensation in the leg and foot. When the foot is unable to dorsiflex, it’s termed a “dropped foot.” When the patient tries to walk they won’t be able to lift their foot and toes off the ground. They’ll need a high-stepping gait from increased hip and knee flexion in order to avoid dragging the foot. Treatment for this motor paralysis includes appropriate bracing and waiting for resolution. Unfortunately, injury to this nerve may result in permanent dysfunction.

Proper Immobilization
There are many splints that work well to immobilize fractures and dislocations. These include adjustable or malleable splints, such as: scissor, ladder, SAM, air and vacuum splints. Immobilize dislocations in the position found unless distal circulation is disrupted. If the limb is flexed, it should be splinted above and below the joint in a sandwich manner with two rigid splints, one placed medially and one laterally. Cross-wrap and secure the limb in position to prevent any movement.

Tourniquet Use
There are many products available to aid in controlling hemorrhage before you should have to resort to the use of a tourniquet on an extremity. However, there are times when tourniquets can be extremely beneficial, preventing a patient from going into shock or exsanguinating.

It’s important to remember exsanguination can occur rapidly depending on the size of the injured vessel and the amount of blood already lost.

Tourniquets have been found to be most beneficial on extremities that are amputated or so badly traumatized that hemorrhage can’t be controlled. Such instances include a plane crash or explosion, gunshot wounds where bleeding cannot be controlled by other means, or when there is significant, uncontrollable arterial damage.1–2

Tourniquets should be applied proximal to the closest joint to the injury—preferably the long bone. (See Figure 5.) The pressure against the long bone has the greatest chance of impairing vascular flow.

Tourniquets are more difficult to apply to lower extremities because of the limb’s circumference as a result of increased muscle mass and adipose tissue in the area, chiefly the uppermost thigh region.

If you do apply a tourniquet, you must ensure there’s nothing impeding its use, such as items in the patient’s pocket or bunched clothing. Application over these objects can cause tourniquet failure, isolated trauma below the object, pressure ulcers, and skin breakdown from direct pressure of the object onto overlying skin.

For the latest research on tourniquet use, see the JEMS War on Trauma supplement at www.jems.com/special/war-trauma.

Conclusion
The CDC estimates that unintentional injuries involving crashes and accidents are to blame for a large portion of deaths in the United States.3 Orthopedic injuries, while rarely cited as a cause of death, often are involved in these events.

Understanding orthopedic injuries leads to appropriate treatment and limits secondary complications and further morbidity. This article serves to reinforce early and appropriate assessment and field management of fractures and knee joint dislocations.

Remember that dislocations are not minor injuries. If confronted with an extremity fracture or knee dislocation locked in an unusual position, make sure basic splinting needs are not neglected or overshadowed by the zeal to perform ALS care.

References
1. Markenson D, Ferguson JD, Chameides L, et al. Part 17: First aid: 2010 American Heart Association and American Red Cross guidelines for first aid. Circulation. 2010;122(18 suppl. 3):S934–S946.
2. Welling DR, Burris DG, Hutton JE, et al. A balanced approach to tourniquet use: Lessons learned and relearned. J Am Coll Surgeons. 2006;203(1):106–115.
3. Ten leading causes of death and injury. (Aug. 8, 2013.) In Centers for Disease Control and Prevention. Retrieved Feb. 9, 2

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