Emergent General Assessment
The initial evaluation of musculoskeletal (MSK) injuries is dictated by the severity of the injury and risk to limb or life. Presentations of significant mechanisms of injury, such as a fall from 20 feet, are approached using the Advanced Trauma Life Support algorithms to ensure life-threatening injuries are prioritized and stabilized before proceeding to non–life-threatening injuries. See Chapter 20 for an approach to trauma evaluations.
After determining that the patient is stable, a focused MSK examination starts with the visual inspection for gross limb deformities, soft-tissue edema, soft-tissue defects, passive positioning of limbs, limb length discrepancies, and skin tone. Vasculature is assessed by palpating peripheral pulses and checking capillary refill and distal extremity warmth. Loss of a pulse is an orthopedic emergency, and immediate intervention is essential to limb survival. Joints are evaluated for impairments in active and passive range of motion (ROM). Bones are palpated for tenderness or step-offs, and ligamentous laxity is assessed by provocative maneuvers. It is important to thoroughly evaluate injuries at least one joint above and below the site of injury to avoid missing adjacent injuries. Neurologic function is assessed by evaluating strength and sensation.
Immediate General Interventions
Always make sure that a patient is fully undressed and placed in a gown so that they can be thoroughly examined. Remove any jewelry or accessories on or near injured body parts. As the injured region becomes more edematous, circumferential accessories may inadvertently become tourniquets. Jewelry and clothing can also interfere with the interpretation of radiographic imaging by overlying fractures or appearing as foreign bodies.
Immobilization is an essential intervention for MSK injuries, especially those with high risk of nerve or vascular injury. Patients with a high-energy mechanism of injury with midline cervical and/or thoracolumbar vertebral tenderness require a cervical collar and/or logroll precautions, respectively. Fractures, dislocations, and soft-tissue injuries potentially involving bone are commonly immobilized in the prehospital setting, but if not, they should be immobilized as soon as possible in the emergency department (ED). ED technicians (EDTs) can use readily available supplies in the ED including rolled blankets, intravenous (IV) arm boards, or preformed fiberglass/aluminum splints to carefully support the injury while the patient is awaiting a medical provider. Care should be taken to ensure that the extremity remains vascularly intact during movement and immobilization. When possible, elevate the injured body part with 1 or 2 pillows, and place ice packs to reduce edema and pain.
Common Musculoskeletal Injuries
Sprains and Strains
Tendons and ligaments are collagenous connective tissues that are inelastic and can withstand high tension. A tendon attaches muscle to bone, whereas a ligament attaches bone to bone. A sprain involves an injury of ligaments that join two or more bones (e.g., ankle sprain). A strain involves an injury of muscle or tendon (e.g., lumbar strain). Either can result from traumatic or atraumatic etiologies (e.g., overuse injury).
Ankle Sprains
The most common mechanisms of injury of ankle sprains are inversion (foot rolls inward) and eversion (foot rolls outward) at the ankle joint. Tenderness of the lateral aspect of the ankle suggests injury to the anterior tibiofibular ligament and/or calcaneofibular ligament, whereas medial aspect tenderness suggests injury to the deltoid ligament. Plain films (i.e., x-rays) are often used to differentiate an ankle sprain from an ankle fracture.
The Ottawa Ankle Rules ( Fig. 18.1 ) is an evidence-based clinical decision-making tool that helps clinicians to determine whether an x-ray is appropriate and to minimize unnecessary costs and exposure to radiation.
Management of most MSK injuries, including sprains, includes RICE therapy (i.e., rest, ice/immobilize, compression, and elevation).
Rest: Limited weight bearing initially followed by progressive weight bearing as tolerated. Crutches or a cane may be required for weight support.
Ice/Immobilization: Ice over cloth or a cold compress for 10 to 20 minutes three or more times per day for 48 to 72 hours.
Compression: All-cotton elastic (ACE) wrap or premade pneumatic ankle splints.
Elevation: Elevate the area of injury above the level of the heart as often as possible until swelling resolves.
Wrist Sprains
A fall on outstretched hand (FOOSH) is the most common mechanism of wrist sprains. Other common mechanisms include hyperflexion/extension at the wrist and overuse injuries stemming from poor ergonomics at work. Plain films may be performed depending on the mechanism or injury. Management of wrist sprain includes RICE therapy. Immobilization is achieved with premade wrist splints (e.g., cock-up wrist, thumb spica splints). Chapter 19 covers splints in detail.
Knee Sprains
Minor trauma of the knee involving hyperflexion/extension or varus/valgus may result in knee sprain. Initial assessment includes looking for obvious deformity, patellar displacement, weakness, joint laxity, and effusion. ROM assessment is done through a series of specific examinations in which the provider assesses individual ligaments, as well as possible injury to the joint cartilage. Redness or erythema of the joint and warmth to touch suggest an inflammatory response requiring evaluation, potentially including blood work and analysis of joint fluid obtained by arthrocentesis, to evaluate for potential infection (septic joint).
In the case of significant knee strains and sprains, immobilization of the knee joint may be required. This is accomplished with an elastic bandage or a premade knee immobilizer and accompanying crutches. Patients should implement RICE therapy and may bear weight as tolerated.
Tendon and Ligament Ruptures
More serious injuries can result in the complete disruption of tendons and ligaments or avulsion of the bone where a tendon or ligament inserts.
Achilles Tendon Rupture
The Achilles tendon has the primary function of plantar flexion. The mechanism of injury commonly involves sudden and forceful ankle dorsiflexion (e.g., landing after a jump shot). Risk factors for Achilles tendon rupture include chronic steroid use, fluoroquinolones, male gender, and chronic high heel use. The examination may reveal a palpable defect along the Achilles tendon, and diagnosis is supported by inability to plantarflex and a positive Thompson test (i.e., no passive plantarflexion with calf squeeze by examiner) ( Fig. 18.2 ). Management includes RICE, immobilization with a short posterior mold splint with the ankle at 110 degrees plantarflexion to reapproximate the separated tendon, crutch walking with no weight bearing, and referral to orthopedics for nonoperative versus surgical repair for the tendon.
Knee Ligament and Tendon Ruptures
There are four ligaments responsible for maintaining the stability of the knee joint: the medial and lateral collateral ligaments and the anterior and posterior cruciate ligaments ( Fig. 18.3 ). As mentioned earlier, each knee ligament and tendon is tested by specific maneuvers that challenge the integrity of the structures. Any perceived laxity or instability suggests a ligamentous injury, which can be confirmed by magnetic resonance (MR) imaging, typically on outpatient follow-up.
The quadriceps tendon, inserting at the proximal patella, and the patellar tendon, inserting at the distal patella, are responsible for leg extension. Ruptures to either of these structures may result in a palpable defect and inability to lift and extend at the knee. Partial and complete tendon ruptures can be confirmed by ultrasound or MR imaging.
Ligament and tendon ruptures of the knee require orthopedic evaluation, which may occur in the ED, and follow-up. Acute management includes RICE, knee immobilization, and crutch walking.
Fractures
Fractures involve a break in the cortex of the bone and are categorized as follows ( Fig. 18.4 ):
Nondisplaced: There is no disruption of bone alignment.
Displaced: The bone alignment is disrupted.
Angulated: The distal portion of the bone is tilted away from the axis of the proximal portion of the bone.
Intraarticular: The fracture extends through the articular surface.
Comminuted: The bone is fragmented into three or more pieces.
Avulsion: There is separation of bone at the site of tendon insertion.
Pathologic: The fracture occurs with a low-energy mechanism and is accompanied by an underlying condition that predisposes to fracture (e.g., osteoporosis, bone metastasis).
Open: There is a soft-tissue defect overlying the fracture, thereby exposing the fractured bone to contamination and infection. Almost all open fractures require copious sterile irrigation, IV antibiotics, and ED orthopedic consult.
Pediatric fractures can occur along growth plates, thereby affecting bone growth. These types of fractures are categorized by the Salter-Harris classification system ( Fig. 18.5 ). Other fractures common in children include greenstick fractures, which involve a rupture of one side of bone with intact periosteum of the opposite aspect of the bone, and buckle fractures, which involve a compaction mechanism resulting in flaring out of unilateral or bilateral aspects of the bony cortex on plain films.
