Chapter 27 Wilderness Orthopedics

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The textbook discussion of orthopedic trauma in wilderness medicine has traditionally focused on discrete musculoskeletal injury to individuals or small groups in the mountain, sea, or desert setting. The scope of wilderness medicine today has widened significantly to include terrorism, military engagement, and the forces of nature. Recent disasters, such as the Great Indian Ocean tsunami of 2004, Hurricane Katrina in August 2005, and the Haitian and Chilean earthquakes of 2010, serve as powerful examples of situations in which orthopedic injuries were myriad and the provision of care limited in significant part by the remoteness of setting or inaccessibility of resources.

The wilderness practitioner needs to approach trauma outside the normal clinic or hospital setting with a sense of anticipation and improvisation. One needs to be prepared for a scenario of chaos, inadequate medical supplies or support, sepsis, and limited or delayed evacuation potential. The tidy fractures of individual sport injury or accidental trauma in civilized society share little in common with massive crush injuries, limb mangling with segmental loss, and severed limbs of natural or terroristic disasters. Issues of triage and prioritization become paramount. The successful organization of resources and effective mobilization of personnel skills often determine the outcome of the operation. Improvisation in splinting to stabilize or immobilize shattered limbs can minimize neurovascular compromise and reduce morbidity and mortality (Figure 27-1). Although most of us will hopefully not experience such large-scale tragedy, readiness and focus are required of the modern wilderness caregiver!

FIGURE 27-1 Improvised traction following the 2010 earthquake in Haiti.

(Courtesy Sam Slishman.)

Problem Scope

Musculoskeletal injuries account for 70% to 80% of injuries that occur in a wilderness setting.^11,¹⁸ Presumably as a result of the use of flak jackets and core protective gear that shield axial and central anatomic structures, bone and soft tissue injuries have also accounted for 70% of injuries in the Iraq and Afghanistan wars.¹⁶ In the initial management of a musculoskeletal injury that occurs in a wilderness or nondeveloped setting, the following must be considered: etiology and time of the injury, direction of the causative force in relation to the individual or limb, and environment where the accident occurred. These factors may indicate the severity of the injury and help determine examination and treatment priorities that can affect outcome.

Stabilization of a victim’s cardiovascular and pulmonary status is critical. Once this has been accomplished, examination of the musculoskeletal system should be undertaken in a systematic manner. Careful initial attention should be devoted to the spine. After the cervical, thoracic, and lumbar spine are evaluated and stabilized, the focus is brought to bear on the pelvis and extremities.

Physical Examination

The physical examination should address respiratory, circulatory, nerve, skeletal, and joint function.

Potentially Life-Threatening Musculoskeletal Injuries

Spinal Injuries

Cervical Spine

In the wilderness, cervical spine fractures or dislocations can be the result of a fall from a height, a high-velocity ski crash, in a combat setting, or a diving accident. Because head and cervical spine injuries are highly associated, a victim with a significant head injury should be considered to have a cervical spine injury, especially if the individual is unconscious. Ideally, a person with a suspected cervical spine injury is placed on a backboard with neck immobilization to prevent further injury and promptly evacuated. Approximately 28% of persons with cervical spine fractures also have other spinal fractures.³ Therefore the person providing care must protect the entire spine.

When a cervical spine injury is suspected, the field examination involves grading motor strength, documenting sensory response to light touch and pinprick, and noting the presence or absence of the Babinski reflex (see Figure 27-3). When appropriate supplies are available, a rectal examination should be done. Complete lack of tone and failure of the sphincter muscles to contract when pulling on the penis or clitoris (the bulbocavernosus reflex) indicates spinal cord injury.

Neurologic deficit often results from cervical spine fracture. Complete neurologic injury from the occiput to the C4 level is usually fatal because of paralysis of the phrenic nerve, diaphragm, and respiratory muscles. The corollary to this is that surviving victims generally have partial deficits or are neurologically intact. Axial cervical spine fractures may result from flexion forces (most common), extension forces, rotational forces, or a combination of these. Cervical spine fractures most commonly occur at C5-6.³ Fracture of the C1-2 complex results from axial loading (a C1 ring fracture, or Jefferson’s fracture) (Figure 27-4) or from an acute flexion injury (a C2 posterior element fracture, or hangman’s fracture) (Figure 27-5). A pure flexion event may dislocate one or both posterior facets, producing neck pain and limitation of motion. Because the interspinous ligament is ruptured and this fracture dislocation is highly unstable, victim transport must be done with the neck rigidly immobilized to reduce the risk for posterior motion.

FIGURE 27-4 C1 ring, Jefferson’s fracture.

FIGURE 27-5 C2 hangman’s fracture.

Fractures and dislocations may result in neurologic insult distal to the bony injury. Because flexion injuries are the most common cervical spine injuries, the neurologic deficit is generally an anterior cord syndrome. In this setting, the victim suffers complete motor loss and partial sensory loss but retains proprioception.

Thoracolumbar Spine

Thoracolumbar spine fractures occur most frequently at the T12-L1 junction. Because the thoracic spine is well splinted by the thoracic cage, when an axial or flexion load is applied, the ribs diminish forces on the thoracic vertebral bodies and transmit the force to the upper lumbar levels. In the wilderness, falls from significant heights or a high-velocity sporting vehicle crash may produce these fractures (Figure 27-6). Thoracolumbar spine fracture may also be associated with other fractures that occur with axial loading, such as femoral neck fractures (Figure 27-7) and calcaneus fractures (Figure 27-8). These injuries commonly occur when there is an axial force, such as a fall onto the lower limbs from a height. Therefore an individual who sustains a presumed hip fracture or calcaneus fracture as the result of a fall from a height generally should be transported under spinal precautions.

FIGURE 27-6 Wedge compression fracture from axial or flexion loading at the thoracolumbar junction.

FIGURE 27-7 High-energy basicervical femoral neck fracture with greater trochanter fracture after a 40-foot fall while rock climbing.

FIGURE 27-8 Calcaneus fracture.

When a thoracolumbar spine fracture is suspected, a careful neurologic examination should be performed as part of the secondary survey, and close attention should be paid to the dermatomal response to light touch and pinprick, motor function, and the presence or absence of cord level reflexes. Because significant fluctuations in sympathetic tone may occur, the rescuer should monitor blood pressure and body temperature, taking appropriate steps to cool or warm the victim. If evacuation cannot be performed immediately, hemodynamic and neurologic function should continue to be noted and documented. The victim should be logrolled, maintaining perfect spinal alignment, and carefully placed on a backboard. The scoop stretcher may be used in this situation (see Chapter 19).

Pelvic Injuries

A study of mortality in the wilderness setting in Pima County, Arizona, between 1980 and 1992 demonstrated that most deaths occurred as a result of falling or drowning.¹² Pelvic fractures generally occur with a fall from significant height, high-velocity ski accident, or vehicle crash. The Young and Burgess classification of pelvic fractures is based on the mechanism of injury. Pelvic fractures are categorized as anteroposterior compression injuries, lateral compression injuries, and vertical shear injuries.⁵ These fracture patterns have been shown to correlate with blood loss, associated injuries, multisystem morbidities, and mortality.^5,^7,³¹ Anteroposterior compression injuries can result in rotational instability if there is greater than 2.5 cm (1 inch) of pubis symphysis separation (Figure 27-9). Furthermore, if the posterior pelvic ring is disrupted, this can lead to both rotational and vertical instability. These fractures, which may include acetabular fractures, are often accompanied by hemorrhagic, neurologic, urologic, gynecologic, and gastrointestinal injuries (Figures 27-10 and 27-11).

FIGURE 27-9 Pelvic injury after being thrown from a horse. Pubic symphysis widening of greater than 2.5 cm (1 inch) is generally considered to be unstable.

FIGURE 27-10 Highly unstable pelvic ring injury with pubic rami fractures and displaced iliac wing fracture. This patient also had a severe bladder injury.

FIGURE 27-11 Right hip dislocation with acetabular and femoral head fractures.

Because the posterior pelvic ring accounts for about 60% of pelvic stability, in a suspected pelvic fracture, it should be determined whether there is an injury to the posterior pelvis. Posterior pelvic fractures are identified by instability of the pelvis associated with posterior pain, swelling, and ecchymosis. This victim should be immediately evacuated on a backboard, taking care to minimize leg and torso motion.

Hemodynamic instability may occur with pelvic fractures, especially if the injury is the result of translational or shear forces or if the posterior pelvic structures are primarily involved. Bleeding associated with a pelvis injury is usually from cancellous bone at fracture sites, a retroperitoneal lumbar venous plexus injury, or, rarely, pelvic arterial injuries. Medical antishock trousers, the portable SAM sling, or even a bedsheet wrapped around the pelvis of an individual with a suspected unstable pelvic fracture may provide stability and accomplish adequate tamponade of bleeding from the fracture ²² (Figure 27-12). Other similar devices are available or may be improvised. The applied sling belt (pelvic binder) or similar contrivance should be left in place until definitive care is available (Figure 27-13). Degloving injuries can also be seen in high-energy pelvis injuries (Figure 27-14).

FIGURE 27-12 SAM sling.

FIGURE 27-13 Appropriate application of a sheet for an unstable pelvic fracture (centered at the greater trochanters, as opposed to the iliac wings).

FIGURE 27-14 Prone patient with an unstable pelvic fracture and a large degloving (Morel-Lavallée) flank lesion.

In addition to these high-energy injuries, simple, nondisplaced inferior or superior ramus fractures and avulsion fractures can occur. On clinical examination, these pelvic fractures are generally appreciated as areas of tenderness without instability. Lateral compression injuries are usually stable, with impaction of the posterior structures.

Extremity Injuries—General Considerations

Splinting Techniques

Splinting in the wilderness is performed so that alignment is maintained and further soft tissue injury is minimized. A victim with suspected cervical or thoracolumbar spine trauma should be transported on a hard surface. Backboards or scoop stretchers (see Chapter 19) are most effective, but improvisation with hard pieces of wood, fiberglass, or straight tree limbs lashed together may be needed. If cervical spine injury is suspected, a roll of clothes or a water bottle can be placed as high as the victim’s midface on either side of the head to prevent rotational movement. Tape applied from the supporting stretcher across the objects and the victim’s forehead adds stability. A child with a suspected spine injury should be transported on a backboard with the child’s body slightly elevated relative to his or her head (Figure 27-15). Any victim with a suspected major pelvic injury is transported in a similar fashion, stabilizing the pelvis with a circumferential sheet or piece of clothing or special belt and holding the lower extremities as immobile as possible, with the knees slightly flexed (see Figure 27-12).

FIGURE 27-15 Child with suspected spine injury should be transported on a backboard with the child’s body slightly elevated relative to his or her head.

Many different extremity splints are available for use in the wilderness setting. These splints are lightweight, compact, and easy to use. They are, of course, more elaborate than a hiking pole or branch that is more readily available. These more intricate devices have considerable advantages for larger-scale evacuations in the setting of natural disasters. They are designed to provide traction through the injured extremity while using the intrinsic properties of the splint and the injured limb to apply the traction. With proper splint application, the injured limb can be immobilized securely in a functional position until definitive care is reached (Figure 27-16).

FIGURE 27-16 Lower extremity splints.

Air splints may be of some benefit, but they are generally manufactured in one shape. Especially in the setting of injured tissues and in environments that might include wide temperature variability, these splints can cause compressive damage to an already injured extremity. Therefore, in more extreme conditions, an air splint is used only if it has an automatic adjustment valve to account for atmospheric variability. Also, these splints should be stored in a minimally inflated state when the temperature is below freezing, to prevent ice from causing splint dysfunction. Beaded vacuum splints can also be used. However, temperature and altitude considerations can make adequate and consistent inflation less reliable. When beaded vacuum splints and air splints are used, vigilance is required to ensure that no excessive pressure is applied to already injured soft tissues.

Upper extremity splints may also be made from plaster or fiberglass, which can be applied over a soft cotton roll. Lightweight fiberglass splints, such as Ortho-Glass and FareTec, are easy to use and effective in the initial management of these injuries (Figure 27-17). These splints are prepadded and can be applied with either cold or warm water. The warmer the water, the faster the fiberglass sets and the greater the exothermic reaction. Hot water should be avoided because it may generate an excessively exothermic reaction and possibly burn the skin. The fiberglass is immersed in water, excess water is gently squeezed out, and the splint is applied. An elasticized bandage helps hold the splint where desired until the fiberglass is hard. Air splints, when inflated, can adequately splint the upper extremity in a stable position. Wooden or metal splints, custom made or improvised, also can be used to stabilize an injured extremity. New thermoplastic casts and braces may be used in a wet outdoor environment and immersed in water without compromising function or stability (Figure 27-18).

FIGURE 27-17 Water-activated FareTec splint for distal radius fracture, with wrist and hand in position of function.

FIGURE 27-18 Swimmer in Exos fracture brace.

Hand splints are applied with the metacarpophalangeal (MCP) joints flexed to 70 to 90 degrees and the interphalangeal (IP) joints extended. This position places the collateral ligaments at maximal length and prevents joint contracture (Figure 27-19). Wrist or forearm splints are applied with the wrist in a neutral position; excessive wrist flexion or extension might detrimentally affect median or ulnar nerve function in an already compromised limb. The elbow is positioned in a splint or sling at 90 degrees, if possible.

FIGURE 27-19 Hand and wrist in position of function.

For shoulder fractures or dislocations, a commercially available sling or improvised triangular bandage should be used to take the weight of the arm off the injured structures. Although it may be difficult to place an injured elbow in 90 degrees of flexion and neutral rotation, the upper extremity should be splinted in the position of comfort and function whenever possible.

For the lower leg, air splints provide adequate immobilization of tibia or fibula fractures and of ankle fractures and dislocations. Splints made from plaster or fiberglass may be applied over cotton padding and held in position with elasticized bandages. The SAM Splint, an excellent first-aid item that may be molded to immobilize a wide variety of injuries, provides stability and strength through its aluminum and foam core (Figures 27-20 and 27-21). The aluminum structure can be bent into three configurations to provide different degrees of stability, flexibility, and immobilization. The ankle is held in neutral position and the splint applied firmly. For transport, the lower extremity is positioned with the hip and knee extended and the ankle in neutral position. Victims with unstable lower extremity fractures or dislocations are transported in the recumbent position with the afflicted limb elevated.

FIGURE 27-20 SAM Splint.

FIGURE 27-21 Versatile splint for upper or lower extremity.

For hip or femur fractures or dislocations, traction is applied whenever possible, improvising as necessary. For suspected hip, femur, or knee injury, one of multiple splints can be used. The basic principle guiding application of these is to provide traction of the lower extremity using a lightweight device (Figures 27-22 and 27-23). The ischium and/or pubis are proximal structures against which the splint is set. The ankle is usually the structure through which traction is applied (Figure 27-24). Lightweight splints that may be of use in the wilderness setting include those known either by their manufacturer or developer, such as Donway, Thomas, Kendrick, Slishman, Reel, FareTec, Sager, CT-6, and Hare (see Chapter 19). It behooves a backcountry health care provider to be familiar with whichever splinting device he is carrying. If commercial splints are unavailable, the injured leg is strapped to the noninjured leg, with a tree limb or walking stick placed between them. If possible, the victim is transported on a backboard.

FIGURE 27-22 Slishman splint applied for femur fracture following the 2010 earthquake in Haiti.

(Courtesy Sam Slishman.)

FIGURE 27-23 Lower extremity splint.

FIGURE 27-24 Improvisation of an ankle wrap to be used for traction.

Reduction and Relocation Maneuvers

Even in the wilderness, the four principles of fracture reduction should be followed:

• Traction: in-line or longitudinal force application

• Fracture fragment disengagement; included in this step is recreation of the forces that created the fracture

• Reapposition of fracture ends

• Counteraction of forces that lead to deformity

Steady traction and patience are the mainstays of fracture and dislocation reduction maneuvers.⁴

For distal radius fractures, the usual dorsiflexion deformity is reproduced and a flexion force is applied through the fracture. Steady traction can also assist with reduction of these fractures (Figures 27-25 to 27-27 ).

FIGURE 27-25 Reduction maneuver for the most common distal radius fracture (dorsally angulated).

FIGURE 27-26 Distal radius fracture with distal radioulnar joint dislocation sustained after a fall on an outstretched hand.

FIGURE 27-27 Reduced fracture dislocation.

For ankle fractures, traction is applied. Most fractures are the result of an eversion, external rotation force. Therefore reduction is undertaken and a splint applied so that the ankle is in inversion and internal rotation, known as the Quigley maneuver. Care must be taken in the absence of diagnostic imaging so that excessive force on a limb, which has already sustained significant vascular or nerve injury, is not exerted (Figure 27-28).

FIGURE 27-28 Quigley maneuver for ankle fracture reduction. Anterior and inversion forces on the foot and ankle created by hanging leg by the great toe, held medial to midline of the body (or hung with stockinette as depicted.)

Traction Pins

Skeletal traction is applied in the setting of pelvis or acetabular fracture or lower extremity fractures, such as femur or tibia fracture. This mode of stabilization can be used for temporary or more definitive treatment. This technique can be used in a setting such as a natural disaster (see Figure 27-1).

Distal femoral traction pins are inserted from medial to lateral. The knee is flexed during insertion to facilitate access to the medial aspect of the distal femur and to allow for flexion of the knee once the pin has been placed; if the pin is placed with the knee in extension, the iliotibial band might be tethered and thereby prevent knee flexion. The pin is placed approximately two finger breadths proximal to the adductor tubercle. If the pin is placed too distally, it can enter the intercondylar notch of the knee. If the pin is placed too proximally, it can injure the superficial femoral artery near its exit from the adductor hiatus, or one of the branches of the superficial femoral artery, near the knee.

Proximal tibial traction pins are inserted from lateral to medial. The pin is placed approximately two finger breadths distal to the tibial tubercle and two finger breadths posterior to the anterior tibial crest. These pins should not be placed in children, if possible; proximity of the tibial tubercle physis puts this important structure at risk during insertion of a proximal tibial traction pin (Figure 27-29).

FIGURE 27-29 Proper positioning of distal femoral and proximal tibial traction pins.

A calcaneal pin can also be used for applying lower extremity traction. This type of traction pin may be of particular benefit in the setting of ipsilateral femur and tibia injuries. It is usually placed medial to lateral, with care taken to avoid the posterior tibial neurovascular bundle. The pin is driven through the calcaneus and exits laterally (Figure 27-30).

FIGURE 27-30 Calcaneal traction pin placement—slightly more anterior than is usually desired—in the setting of subtalar dislocation.

If possible, balanced traction should be maintained. This helps to counteract deforming forces and to allow for relatively comfortable movement in bed. There are no hard-and-fast rules for the amount of weight to apply. If balanced traction is employed, the rule of thumb is for enough traction to be applied that the ipsilateral buttock is elevated just barely off the bed. When radiography is available, traction is applied until the fracture fragments are well aligned and nearly out to length. For an average-sized adult, this likely will be between 6.8 and 13.6 kg (15 and 30 lb).

Open Fractures

Recognizing an open fracture is imperative; without prompt surgical treatment, the incidence of osteomyelitis in this setting is high.¹⁴ In an open fracture, the fractured bone communicates with a break in the skin. With subcutaneous bones (e.g., tibia), open fractures are easily identified, but with other bones that have more surrounding soft tissue (e.g., humerus, femur, pelvis), identification is more difficult because the fractured bone end usually retracts once it punctures the skin and is then covered by soft tissue. A laceration near a fracture may be an indication of an open fracture. Most open fractures persistently ooze blood or fat globules from the laceration, which may facilitate diagnosis (Figure 27-31). Clothes should be split and skin examined.