Anatomy and Physiology Review
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- The skeleton
- Types of bones
- Ligaments and tendons
Pathophysiology
- Musculoskeletal injuries occur when traumatic forces are applied to bones, joints and connective tissues.
- Traumatic forces that cause musculoskeletal injuries include:
- Direct force—Trauma applied to a specific area
- Indirect force—Trauma applied to one area that damages a different area (as when someone falls and lands feet first but the pelvis breaks as trauma is transmitted up the bones of the leg)
- Twisting/rotational forces
- Crush mechanisms
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- Fracture occurs when the bone is broken:
- Comminuted fractures are characterized by shattered bone or bone broken into several pieces.
- Greenstick fractures are incomplete fractures and cracks in the bone.
- Angulated fractures occur when the fracture of a long bone creates an angle or bend that normally would not be present.
- Extremities and fractures may be open or closed.
- Open extremity injuries are characterized by bone exposed through broken skin or penetrating wounds that injure the bone.
- Injuries to the joint are classified as follows:
- Dislocation—The joint is disrupted and the bones of the joint are now misaligned.
- Subluxation—The joint was temporarily disrupted, but the bones of the joint are now back in place.
- Sprain—The ligaments connecting the bones together were stretched or torn by excessive motion.
- Strain—The tendons connecting muscle to bone were stretched or torn by excessive motion.
- Swelling and bleeding within an extremity can cause compression of soft tissue and diminished blood flow. This condition is called compartment syndrome.
Signs and Symptoms
- Mechanism of injury
- Obvious fractures, including exposed bone ends, angulation and crepitus
- Pain and tenderness
- Loss of function of joint, decreased range of motion
- Bruising
- Swelling
- Loss of distal circulation and sensory or motor function
- Especially with hip fractures, leg shortening or unnatural rotation of the foot
- Signs of impending compartment syndrome, include the “six Ps”
- Paralysis of the extremity
- The sensation of pressure
- Increase in pain
- The sensation of paresthesia (pins and needles)
- Pallor in the extremity
- Diminished or absent pulses
Treatment
- Consider the need for advanced life support for pain management.
- Recognize critical loss of circulation and make transport decisions appropriately.
- Realign angulated fractures with gentle traction. Stop the realignment process if the patient’s pain increases significantly or if you feel resistance.
- Realign joints only if circulation is impaired.
- When splinting:
- Splint musculoskeletal injuries in position of function.
- Splint in a long bone such that the joint above and the joint below the injury are immobilized.
- Splint in a joint injury such that the bone above and the bone below are immobilized.
- Assess circulatory, sensory and motor function before and after splinting.
- Use a traction splint to immobilize an isolated femur fracture.
- Use a pelvic wrap or pelvic binder to immobilize a potentially fractured pelvis.
Important Concepts
- Beware of allowing grotesque musculoskeletal injuries to distract your attention from more immediate life threats.
- For all musculoskeletal injuries, including those in pediatric patients, consider the need for pain management.
- Fractures of the pelvis and femur can pose a risk of internal bleeding and hypovolemic shock.
- Be creative with splinting and do not allow standardized procedures to limit possible methods. It’s the principle, not the application itself, that is important.
- Remember to reassess. As with compartment syndrome, musculoskeletal injuries occasionally change and worsen over time.