EMT-Basic Exam: The Basics of Trauma - Musculoskeletal Care

Musculoskeletal injuries are very common in emergency medical care. The majority of musculoskeletal injuries are relatively simple and do not require advanced treatment. Most of these injuries will only need assessment, splinting, and transport to a medical facility. Some severe musculoskeletal injuries, however, may be life threatening and can necessitate emergency treatment.

1. The Muscular and Skeletal Systems
The musculatory system has three chief duties. Muscles give us shape, protect our internal organs, and allow us to move. There are three kinds of muscles in the body:
- Voluntary muscles, or skeletal muscles, are connected to bones and account for most of the body’s muscle mass. These muscles are commanded by the nervous system and can be voluntarily contracted or relaxed.
- Involuntary muscles, also called smooth muscles, are located in the walls of the gastrointestinal tract, urinary system, blood vessels, and bronchi. These muscles are responsible for automatic tasks such as the flow of blood and bodily fluids and cannot be consciously controlled. Involuntary muscles respond independently to stimuli like external temperature and the stretching that occurs when an organ is full.
- Cardiac muscles are exclusive to the heart and can contract entirely on their own, a property known as automaticity. These involuntary muscles have their own blood supply delivered through the coronary artery system and can only withstand an interruption in this supply for a very brief period.

The skeletal system is composed of the bones of the skull, face, spinal column, thorax, pelvis, and the upper and lower extremities. The purpose of the skeletal system is similar to that of the muscular system in that it also provides body shape, protection for internal organs, and assistance with movement. Muscles and bones, along with various connective tissues, work in conjunction to make movement possible. Movement of the extremities occurs at the joints, the points where bones connect to other bones. The two most common types of joints are ball-and-socket joints, such as the hip; and hinge joints, such as the knees.

2. Injuries to Bones and Joints
In order to effectively treat bone and joint injuries, you must understand the forces that cause these injuries. The greater the force of an injury, the more likely that severe bodily damage will result. These forces are known as the mechanism of injury. You can often use the mechanism of injury to predict the most likely injury, but only a physical examination can determine the severity of a musculoskeletal injury.

Elderly patients are at higher risk of skeletal injuries than other patients because of conditions like osteoporosis, which causes brittle, weakened bones. Arthritis can make immobilization of these patients difficult because they may have angulations that you cannot straighten, such as a spinal curvature. Children, on the other hand, usually have much more flexible and resilient bones. Because of this, the bones may flex instead of fracture, allowing the force to be applied to internal structures. In this way, children can receive internal injuries without sustaining any bone damage at all.
Most musculoskeletal injuries occur as the result of a force applied to a particular part of the body. These injuries are called direct injuries. An example of a direct injury would be someone being hit by projectile, such as a baseball.
Indirect injuries occur away from the point of impact. An example of this type of injury would be a dislocated hip that results from a patient falling from a height and landing on his feet. The bones of the leg are very strong. When force is applied along the leg’s axis, the force is transmitted up the bones of the leg to the hip, which may fracture or dislocate.
Twisting injuries occur when an extremity is pulled and turned beyond its typical range of motion. A typical twisting injury is a sprained ankle.

A musculoskeletal injury can be either open or closed. Open injuries involve a break in the skin and may present with external bleeding. Open injuries also carry a risk of infection. Closed injuries do not include any breaks in the skin, but may be accompanied by internal bleeding.
There are a number of common signs of bone and joint injuries. The injury site may be deformed, angulated, or tender. The patient may experience pain when movement is attempted. In cases where bone ends are separated, you may hear or feel crepitation, or grating, which occurs when the bone ends rub together. Swelling and discoloration are also common. In the event of open bone injuries, the broken end of an injured bone may protrude from the skin. In some cases, the bone may retract back under the skin after protrusion, leaving an open flesh wound with no visible bone. Joint injuries can sometimes result in the affected joint becoming locked and unmovable.

A common type of musculoskeletal injury is a fracture. Fractures result when bones are actually broken or cracked. In addition to fractures, you may encounter dislocations, sprains, and strains. Dislocations occur when the bone ends become separated at the joint. Sprains are partial ligament tears, and strains are tendon injuries. It is generally impossible to differentiate between these injuries in the field and all should be treated as if they were fractures.

3. Emergency Care of Bone and Joint Injuries
If you encounter a bone or joint injury, you should begin, as always, by ensuring a patent airway. When the airway is secure, you should determine if the injury needs to be splinted. Splinting helps protect the patient against further injury from bone ends or fragments. Broken bones or bone fragments can damage muscles, nerves, and blood vessels. Splinting reduces the risk of these injuries. Splinting can also stop a closed injury from becoming an open injury. A splint may reduce the pain associated with a bone injury. The risk of paralysis can also be reduced by splinting.
When applying a splint to an extremity, it is important to note the patient’s pulse, motor function, and sensation distal to the injury before and after the splint is applied. This will help to ensure that the splint has been applied properly and is not interfering with circulation. Before applying the splint, cut away clothing to increase the splint’s effectiveness and properly dress and bandage any open injuries.

Tip: Remember to include the bones and joints above and below the injury site in the splint. This helps to minimize the movement of muscles around the injury site.

In cases where there is severe deformity or when the distal extremity has no pulse, you should align the injury with gentle traction only as far as is necessary to restore circulation. If you feel resistance, it is best to splint the extremity in the position you found it. If distal pulse does not return, rapid transport is indicated to prevent the loss of the limb.
If the patient has an open injury with the bone protruding from the skin, you shouldn’t attempt to replace the bone. In some cases, these bones will move back into place by themselves when the splint is in place. When you apply a splint to a hand or a foot, you should immobilize it in the position of function, which is the relaxed position of the extremity where there is minimal movement or stretching of the muscles.
Lifesaving interventions, including transporting the patient, should never be delayed to apply a splint. In many cases, a patient can be immobilized to a long backboard, which can be used to quickly splint multiple fractures and still allow for rapid transport.

Tip: You may not always be able to tell if an extremity is fractured. Be safe and splint the injury in case a fracture is present.

There are various types of splints used for immobilization.
Rigid splints are nonformable splints that support an injured extremity and immobilize the surrounding joints and bones.
Traction splints are used specifically for femur injuries when there are no accompanying joint or lower-leg injuries. Traction splints should not be used if the injury is near or includes the knee or ankle, there are bone ends protruding from the skin, or there are partial amputations or avulsions.
Pneumatic splints are flexible, conforming splints that are often used with angulated injuries. Some examples of pneumatic splints are air splints, pneumatic antishock garments, and vacuum splints. These types of splints are applied and then filled with or emptied of air.
When using an air splint, you should first cover all wounds with clean dressings. Next, place the extremity inside the splint and inflate with air. Inflation may be achieved by pumping or by blowing into a valve.
Pneumatic antishock garments are often used to immobilize the lower extremities in the event of pelvic instability or injuries to the long bones of the legs that result in shock. In most cases, the garment is placed on the backboard and the patient is rolled or moved on top of it. The necessary compartments can then be inflated. There are various techniques for using pneumatic antishock garments based on the type and location of injury.
Vacuum splints work in the opposite fashion of pneumatic antishock garments and air splints. An already-inflated splint is placed on the injured extremity and a vacuum removes the air, allowing the splint to conform to the area.

There are also a variety of possible improvised splints. Pillows can be used as splints for joint injuries, particularly ankle injuries. A pillow can be wrapped entirely around the ankle and secured. Remember to leave the toes accessible so that you can continue to assess pulse, motor function, and sensation. The sling-and-swathe technique is commonly used for shoulder injuries. The patient’s arm is placed into the sling and the swathe is then wrapped around the arm and body to immobilize the arm and shoulder.
Improper use or application of splints can lead to further injury. Splints can cause the compression of nerves, tissues, and blood vessels. A splint that is applied too tightly or incorrectly can cause a reduction in distal circulation, increased bleeding, or tissue damage. A poorly applied splint can also cause a closed injury to open.
With the splint properly in place, you are ready to begin transport. While transport is in progress, you may apply cold packs to reduce swelling and pain. Unless other injuries or pain prevent it, you should elevate injured extremities to decrease blood flow.

Related Topics You Should Review:
- Skeletal anatomy
- Muscular anatomy
- Types of fractures