Musculoskeletal trauma is frequently encountered in the prehospital setting. In 2007, extremity injuries accounted for over 14 million emergency department visits within the United States.1 Injuries from falls, motor vehicle accidents, sports activities, and pedestrian versus vehicle accidents are commonly encountered. It is imperative that EMS physicians know how to appropriately stabilize and manage these injuries as many result in limb or life-threatening conditions.
Understand the epidemiology of musculoskeletal extremity injuries in the prehospital environment.
Recognize common injury patterns and their mechanisms.
Be familiar with common immobilization techniques and equipment.
Be familiar with common reduction techniques.
Select appropriate destination facilities based on patients’ injuries.
After ensuring the scene of the injury is safe, it is reasonable to consider adhering to the methodology described by courses such as ATLS and PHTLS (prehospital trauma life support) for performance of the primary and secondary survey. Management of airway compromise, respiratory failure, and life-threatening hemorrhage will be addressed elsewhere in this text.
The secondary survey identifies limb-threatening extremity injuries within its later portion as injuries to the head and thorax take early precedence. ATLS guidelines recommend the “ask, look, and feel” approach to evaluation. “Ask:” Awake and alert patients will help identify painful injuries, bleeding, or deficits. “Look:” Expose the patient’s extremities and look for evidence of injury such as bleeding, swelling, deformity, discoloration, or cyanosis. Swelling, especially over large muscle groups, may be indicative of underlying fractures, hematoma formation, or crush injuries. Discoloration and cyanosis of distal extremities suggests ischemia of the affected limb. “Feel:” Palpate extremities to assess for tenderness, loss of sensation, deformity, crepitus, and distal pulses plus perfusion.2
Prior to manipulating any injured extremities, a distal neurovascular examination should be performed. Assess for key extremity pulses, such as radial artery pulses in the upper extremities and dorsalis pedis and posterior tibial artery pulses in the lower extremity. Compare pulses to the contralateral extremity. Also observe and compare capillary refill in distal nail beds. Capillary refill exceeding 2 seconds is generally abnormal. Evaluation of key sensory and motor groups will also provide important information and should be done during this assessment.
Extremities with grossly contaminated open fractures should have dirt and debris removed by saline irrigation or wiping followed by sterile dressing application. Vaseline dressings may be utilized as an initial layer over an open fracture with soft bulky dressings overlying. Extremities with suspected fractures should be immobilized, preferably with a padded splint.
In general, prehospital reduction of fractures is discouraged. Fracture reduction is a painful process which is best accomplished with the assistance of procedural sedation in the emergency department setting. There are, however, situations where prehospital fracture reduction should be considered. These situations include fractures such as midshaft femur and unstable pelvic fractures, as well as fractures with associated neurovascular compromise or major hemorrhage. If distal pulses are absent in an extremity, immediate field assessment for reduction of a related fracture or dislocation by a trained provider should be considered.
Field reduction is controversial. The National Association of EMS Physicians condones fracture reduction by nonphysicians only if a prolonged transport to the hospital exists, while PHTLS recognizes that one to two attempts at prehospital reduction may be attempted if there is evidence of reduced circulation distal to the deformed extremity.3 Generally, fracture reduction is done by recreating the forces which created the fracture followed by continuous axial traction at the distal portion of the extremity until it can be placed back into an anatomically neutral position. Should new neurologic deficit or worsened vascular examination occur after an attempted reduction, return the extremity to its initial position, immobilize it, and transport the patient immediately to a higher level of care.4 Fracture and dislocation management of several selected fractures are reviewed later in this chapter.
Any extremity with obvious or suspected injury following trauma should be immobilized. Without radiographs, it can be difficult to diagnose all but the most obvious fractures. Pain, deformity, open wounds, hematoma formation, or crepitus on palpation along an extremity is suggestive of an underlying fracture.
Splinting offers the benefit of reducing pain and preventing further vascular, muscle, and nerve damage to an injured extremity. It also prevents transforming closed fractures into open fractures.3 On-scene extremity immobilization should not be conducted if it will delay transport of a patient with life-threatening injuries or prevent successful hemorrhage control in major bleeding. Often extremity immobilization can be conducted en route to the hospital, thus not delaying transport time.
Many types of commercially available splints now exist and it is important that each provider be experienced with the appropriate use of the various splinting and immobilization devices they intend to utilize. Splints can be divided into three major types: rigid, soft, and traction splints. The use of lower extremity traction splints is discussed within this chapter’s section on femur fractures.
Rigid splints are manufactured out of plastic, malleable metals, wood, wire, or other materials. They tend to be less flexible and more supportive than soft splints and are usually padded. Rigid splints are usually secured to patients via circumferentially applied tape, bandages, or straps. The joints above and below the injury should be immobilized. In transporting, it is recommended, when possible, to leave the distal portion of the extremity (toes or fingers) outside of the splint so distal perfusion can be reassessed en route.
Vacuum splints are another type of splint used in the prehospital environment. Vacuum splints are very flexible and can be applied in a multitude of different positions. To apply this splint, one provider supports the injured extremity in the position desired for splinting, while the other provider wraps the splint along the length of the extremity and then secures it with a series of straps. Once applied longitudinally and strapped, a hand pump is attached to a small valve stem on the splint and is used to evacuate air from the splint. As air is evacuated, the splint forms to the shape of the injured extremity and becomes rigid. Vacuum splints have the advantage of being able to be applied to injured extremities found in a multitude of positions; this allows for minimal pain to the patient as movement of the extremity is minimized during the splinting process.
Soft splints include slings, bulky immobilizers, and air splints. Slings are used to immobilize suspected clavicle or shoulder injuries, as well as to support the weight of upper extremity splints for patient comfort. They are easy to apply and provide moderate immobilization of the upper extremity.
Bulky splints, such as a sheet of foam, pillow, or towel, can be wrapped around an injured extremity and secured with tape or ties when needed. Most often bulky splints are used to support an injured hand, wrist, or forearm injury.
Air splints come in a variety of shapes and sizes to fit different extremities. They are initially deflated and placed around the injured extremity and then inflated with air to provide support. It is important to note that air splints apply circumferential pressure to wounded extremities. This may exacerbate pain and may further distal ischemia. These splints should not be applied over open fractures. When transportation involves atmospheric pressures changes, as with aeromedical or mountain transport, expansion or decompression of the splint may occur and the pressure should be monitored. Due to some of the concern over these complications air splints may not be the best option for standard prehospital care.
The majority of extremity injuries can be treated with a general approach involving hemorrhage control, gross decontamination, immobilization, and pain control. However, unique approaches to immobilization and reduction techniques are required for some injuries. Several specific injuries that may require specific immobilization or reduction are discussed within this section.
Dislocated shoulders are frequently encountered in the prehospital setting and account for half of all dislocations seen in emergency department. Prehospital reduction of dislocations should be avoided by nonphysician providers unless there is a compelling neurovascular deficit associated, such as loss of distal pulses with an anticipated prolonged transport time. Traumatic injuries which need immobilization, such as a proximal humerus fracture, may appear similar on physical examination to a shoulder dislocation.
The three main subtypes of shoulder dislocations are anterior, posterior, and inferior. The most common dislocation is anterior (90%) and patients usually present with the arm supported on their effected side with a large defect inferior to the acromion (Figure 56-1). The injury usually occurs when a force is transmitted through an externally rotated and abducted arm. The axillary nerve can be injured in up to 15% to 55% of shoulder dislocations and should be assessed by checking sensation over the lateral deltoid.5 Vascular injury is uncommon with shoulder dislocations, but radial pulses should always be assessed. Sling and swath immobilization is appropriate for transport of patient’s with suspected shoulder dislocations.
FIGURE 56-1.
A patient whose right shoulder is anteriorly dislocated. There is a large defect inferior to the acromion on visual examination. (Photo contributor: Frank Birinyi, MD; Reprinted with permission from Knoop KJ, Stack LB, Storrow AB, Thurman RJ. The Atlas of Emergency Medicine. 3rd ed. McGraw-Hill; 2010. Figure 11.1.)
If reduction is required due to the presence of distal ischemia and anticipated prolonged transport, one or two attempts at shoulder reduction may be attempted. There are a number of commonly used techniques for shoulder reduction including external rotation (modified Kocher), scapular manipulation, Milch, traction and counter traction, Stimson, FARES, Cunningham, and Hippocratic.
The external rotation technique is recommended for reduction in the field as this approach has few complications, can be easily employed in the prehospital setting, and often requires little analgesia if performed early. The scapular manipulation, Milch, traction and counter traction, Stimson, and FARES methods are impractical in most prehospital settings. The Cunningham technique is an excellent option, but does require a calm, cooperative patient and is best performed in a controlled and settling environment. The Hippocratic method should never be used, as it is associated with the significant threat of axillary nerve injury. To perform a shoulder reduction with the external rotation technique, the patient should be seated upright or at a 45° angle with arm adducted at their side. The practitioner supports the affected arm at the elbow with one hand and holds the patient’s wrist with the other hand. Slow and steady force is applied to bring the patient’s arm into 90° of external rotation. The shoulder may reduce (generally a “clunk” is felt or shoulder deformity disappears) at this point. If not reduced, the patient’s arm should slowly be raised vertically until either resistance is met or the humerus is elevated to approximately 20° above the horizontal plane (Figure 56-2).
FIGURE 56-2.
External rotation technique reduction of anterior shoulder dislocations. (Reprinted with permission from Tintinalli JE, Stapczynski JS, Ma OJ, Cline DM, Cydulka RK, Meckler GD, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th ed. New York, NY: McGraw-Hill; 2011. Figure 268-14.)
Posterior shoulder dislocations are frequently missed and commonly occur after generalized seizures and electrical injuries. Patients generally note severe shoulder pain and there is often posterior prominence of the shoulder with limited external rotation of the arm on examination. Neurovascular compromise is rare with posterior dislocations.
Inferior shoulder dislocations also known as Luxatio Erecta are very rare and result from hyperextension injury. The patient’s arm will be positioned in roughly 180° of abduction. The head of the humerus is prominent and often palpable within the axilla. Vascular complications are highest among inferior dislocations most often affecting flow within the axillary artery. Reduction of inferior shoulder dislocations is often complicated with a frequent need for general anesthesia or surgical intervention for open reduction.
Elbow dislocations present with severe pain, swelling, and elbow deformity. Posterior elbow dislocations are the most common (90%) and often result from falls onto an extended arm (Figure 56-3). Brachial artery injury and ulnar nerve injury may occur in up to 12% of elbow dislocations.6 Reduction of a suspected elbow dislocation is not recommended in the prehospital environment unless critical limb ischemia is present with an associated prolonged transport time. Differentiating elbow dislocations from fractures requires radiographs as up to 60% of patients with elbow dislocations have an associated fracture.7 Attempted reduction of a dislocation when a fracture exists can worsen injury. Fracture dislocations of the elbow generally require surgical management. Padded board or vacuum splints are well suited for immobilization of suspected elbow dislocations or fractures in the field. Attempts at elbow reduction are not recommended in the field.
Clavicle fractures are very common. They are often seen with sports injuries or seat belt injuries when force is applied directly over the clavicle or when the shoulder is forced into the chest. Clavicle injuries present with pain, swelling, and possible skin tenting at the site of injury. Roughly 80% of fractures occur midclavicle, 15% distal, and 5% proximal.8 Mid and distal clavicle fractures rarely have an associated neurovascular injury. Proximal clavicle fractures require large forces to the chest to fracture and have a higher incidence of thoracic vascular injuries, brachial plexus injury, and pneumothorax. Suspected clavicle fractures are stabilized in the field by immobilization of the affected upper extremity with a sling and swath.
Humerus fractures result from direct blows to the upper arm or via axial loading. Proximal humerus fractures make up nearly 6% of all fractures and humeral diaphyseal fractures less than 2%.9 Falls and motor vehicle injuries account for a large percentage of humerus fractures in the youth. Pathologic fractures can result from relatively minimal injuries in the elderly population. Proximal humerus fractures present with pain, swelling, and limited range of motion at the shoulder, making them difficult to differentiate from shoulder dislocations. Diaphyseal fractures often present with midshaft deformity. A low incidence of neurovascular injury is reported with humerus fractures. The radial nerve is most often injured, although median and ulnar nerve injuries can occur, while brachial artery involvement is rare.10 Proximal humerus fractures are difficult to fully immobilize, but are well suited to immobilization with a sling and swath in the prehospital setting. Diaphyseal fractures should have a rigid splint applied for immobilization. Should neurovascular compromise exist with a prolonged transport, reduction using longitudinal traction may be attempted and followed by application of a padded board splint.
Distal humerus fractures cause pain and swelling, often with associated deformity and instability of the elbow joint. These include supracondylar, intercondylar, and epicondylar fractures. Radial nerve injury is present in about 18% of distal humerus fractures as the radial nerve emerges from the spiral groove of the humerus and is tethered within the intramuscular septum.11,12 Appropriate field management includes splinting with a padded board splint.
Wrist and forearm fractures are frequently encountered after falls onto an outstretched hand. Distal radius fractures are the most common. Patients present with pain and often deformity. Fractures such as Colles fractures are recognized for their classical “dinner fork” appearance where the wrist and hand are notably angulated dorsally. In other instances, the mechanism of injury, such as a direct blow perpendicular to the forearm to defend against an attack, will suggest an ulnar midshaft fracture (night-stick fracture). However, field examination is limited in discriminating many other wrist and forearm fractures plus proximal forearm fractures are often associated with dislocations at the elbow. Neurovascular examination should test function of the median, ulnar, and radial nerves plus assess radial and ulnar pulses. Field immobilization of simple wrist injuries suspicious for carpal involvement may only be splinted with a volar splint. Forearm injuries may be immobilized with a padded board splint.
Radial head subluxation, also referred to as nursemaid’s elbow, is an injury often seen in young children. Subluxation is thought to occur when traction is placed on the extended arm of a child, such as by swinging a child by an arm or grabbing their arm to keep them from falling. The annular ligament of the radial head slips upward, allowing for subluxation at the radiocapitellar joint. It often presents acutely as inability of the child to use the affected arm.11,12 Distressing pain is not associated, but the child will often support their arm at the side with the elbow pronated and have mild tenderness at the radial head. Basic field examination includes palpation of the injured extremity and distal neurovascular examination. In the prehospital environment, reduction is not recommended; rather the injured extremity should be splinted and treated with the presumption that a fracture or other injury exists.
Prehospital care of hand injuries involves four main fundamentals: splinting and prevention of further injury, hemorrhage control, pain control, and care for amputated digits.12 Examination of the hand should assess for gross injury, perfusion, and function initially. Radial and ulnar pulses should be palpated and evidence of distal perfusion to each digit of the affected hand should be assessed by observing capillary refill.