Musculoskeletal trauma involves injury to one or more of the
- Bone: A unit of the skeleton composed of the hardest variety
of connective tissue. Bones give shape and support to the body.
In addition to surrounding and protecting vital organs, they serve
as points of attachment for the muscles of the limbs, making movement
- Joint: The area where two or more bones articulate with one
another. Joints are usually classified in terms of the amount of
motion permitted at the articulation. Most joints of the extremities
are synovial joints, which allow the greatest amount
- Ligament: A bundle of connective tissue forming part of the
fibrous capsule surrounding a joint and attached to it. Every joint
of the extremities is reinforced by two or more ligaments, whose
purpose is to stabilize the joint by confining its movements to
specific planes and preventing movement beyond limits along those
- Tendon: The fibrous structure connecting a voluntary muscle
to bone, cartilage, or ligaments. Tendons enable muscles to produce
motion in the joint or body area to which they are attached.
Orthopedic injuries to these structures include the following:
- Fracture: A disruption of bone tissue. Fractures may be
caused by: (1) an application of force exceeding the strength of
the bone, (2) repetitive stress, or (3) an invasive process that
undermines the bone’s integrity.
- Dislocation: Complete disruption of a joint, such that the
articular surfaces of the bones that comprise the joint are no longer
in contact with one another.
- Subluxation: Partial disruption of a joint, in which some
degree of contact between the articular surfaces remains.
- Fracture-dislocation or fracture-subluxation: Disruption of
a joint combined with fracture of at least one of the bones involved
in the articulation.
- Strain: A tearing injury to muscle fibers resulting from excessive
tension or overuse.
- Sprain: A tearing injury to one or more ligaments of a joint,
which occurs when the joint is forced beyond the limits of its normal
plane of motion.
Properly assessing and treating bony injuries in the ED requires
an understanding of the physiologic processes by which fractures
are created and by which they heal. Practical knowledge of fracture
pathophysiology may provide the index of suspicion needed to diagnose
an injury that might otherwise be missed. It also may help prevent
or minimize complications and sometimes may form the basis for advising
the patient regarding the outlook for recovery of function.
Although fractures are sometimes classified in terms of the mechanism that
created them, they also may be described in terms of the physiology involved.
Most fractures are the result of significant trauma to healthy
bone. The bony cortex may be disrupted by a variety of forces, including
a direct blow, axial loading, angular (bending) forces, torque (twisting
stress), or a combination of these.