Chapter 31: Orthopedic Injuries

Skeletal muscles

* Also called striated muscle (because of its characteristic stripes) or voluntary muscle (because it is under direct voluntary control of the brain)
* Attaches to the bones and usually crosses at least one joint
* Movement is the result of several muscles contracting and relaxing simultaneously.
* Skeletal muscle tissue is attached directly to the bone by tough, ropelike structures known as tendons, which are extensions of the **fascia** that covers all skeletal muscle.
* Fascia surrounds and supports the muscles and neurovascular structures.

Fascia

the fiberlike connective tissue that covers arteries, veins, tendons, and ligaments

Smooth muscles

* Also called involuntary muscle because it is not under voluntary control of the brain
* Performs much of the automatic work of the body
* Found in the walls of most tubular structures of the body, such as the gastrointestinal tract and the blood vessels
* Contracts and relaxes to control the movement of the contents within these structures

Cardiac muscles

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* A specially adapted involuntary muscle with its own regulatory system

Skull

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* A solid, vaultlike structure that surrounds and protects the brain

Thoracic cage

* Protects the heart, lungs, and great vessels; the lower ribs protect the liver and spleen
* The bony spinal canal encases and protects the spinal cord.

Pectoral girdle

* Also referred to as the shoulder girdle
* Consists of:
* Two scapulae (shoulder blades)
* Flat, triangular bones held to the rib cage by powerful muscles that buffer it against injury
* Two clavicles (collarbones)
* Slender, S-shaped bones attached by ligaments to the sternum on one end and to the acromion process on the other
* Act as a strut to keep the shoulder propped up
* Because they are slender and very exposed, these bones are vulnerable to injury.

Upper extremity

* **Extends from the shoulder to the fingertips**
* humerus, elbow, and radius and ulna
* The upper extremity **joins the shoulder girdle at the glenohumeral joint and begins with the humerus**
* The humerus connects with the bones of the forearm—the radius and ulna—at the elbow to form the hinged elbow joint.
* The radius, the larger of the two forearm bones, lies on the thumb side of the forearm.
* The ulna is narrow and is on the little-finger side of the forearm.
* Because the radius and the ulna are parallel, when one is broken, often the other is broken as well.
* The hand contains three sets of bones:
* Wrist bones (carpals)
* The carpals are vulnerable to fracture when a person falls on an outstretched hand.
* Hand bones (metacarpals)
* Finger bones (phalanges)
* Phalanges are more apt to be injured by a crush injury, such as being slammed in a door.

Pelvis

* Supports the body weight and protects the structures within the pelvis: the bladder, rectum, and female reproductive organs
* The pelvic girdle is actually three separate bones—the ischium, ilium, and pubis—fused together to form the innominate (or hip) bone.
* The two iliac bones are joined posteriorly by tough ligaments to the sacrum at the sacroiliac joints.
* The two pubic bones are connected anteriorly by equally tough ligaments to one another at the pubic symphysis.
* These joints allow very little motion, so the pelvic ring is strong and stable.

Lower extremity

* Consists of the bones of the thigh, leg, and foot
* The femur (thighbone) is a long, powerful bone that connects in the ball-and-socket joint of the pelvis and in the hinge joint of the knee.
* The lower leg consists of two bones:
* Tibia (shinbone)
* Fibula
* The foot consists of three classes of bones:
* Ankle bones (tarsals)
* The largest of the tarsal bones is the heel bone, or **calcaneus**, which is subject to injury with axial loading injuries, such as when a person jumps from a height and lands on the feet.


* Foot bones (metatarsals)
* Toe bones (phalanges)

Tibia

the shinbone; the larger of the two bones of the lower leg, responsible for supporting the major weight-bearing surface of the knee and the ankle

Fibula

the outer and smaller bone of the two bones of the lower leg

Calcaneus

the heel bone

Joints

places where two bones come into contact

Ligaments

a band of fibrous tissue that connects bones to bones. It supports and strengthens a joint

Articular cartilage

a pearly white layer of specialized cartilage covering the articular surfaces (contact surfaces on the ends) of bones in synovial joints

Zone of injury

the area of potentially damaged soft tissue, adjacent nerves, and blood vessels surrounding an injury to a bone or a joint

Significant force may be applied to the limb in any of the following ways:

* Direct blows
* Indirect forces
* Twisting forces
* High-energy injuries

Fracture

a break in the continuity of the bone, often occurring as a result of an external force

Closed fracture

any break in a bone in which the overlying skin is not broken

Open fracture

any break in a bone in which the overlying skin has been broken

Nondisplaced fracture

(also known as a hairline fracture) is a simple crack of the bone that may be difficult to distinguish from a sprain or simple contusion

Dispalced fracture

a fracture in which bone fragments are separated from one another, producing deformity in the limb

Comminuted

a fracture in which the bone is broken into more than two fragments

Epiphyseal

a fracture that occurs in a growth section of a child’s bone and may lead to growth abnormalities.

Greenstick

an incomplete fracture that passes only partway through the shaft
 of a bone but may still cause substantial angulation; occurs in children

Incomplete

a fracture that does not run completely through the bone; a nondisplaced partial crack

Oblique

a fracture in which the bone is broken at an angle across the bone. This is usually the result of a sharp, angled blow to the bone

Pathologic

a fracture of weakened or diseased bone, seen in patients with osteoporosis, infection, or cancer; often produced by minimal force

Spiral

a fracture caused by a twisting or spinning force, causing a long, spiral-shaped break in the bone. This is sometimes the result of abuse in young children

Transverse

a fracture that occurs straight across the bone. This is usually the result of a direct-blow injury

Deformity

* The limb may appear to be shortened, rotated, or angulated at a point where there is no joint.
* Always use the opposite, uninjured limb as a mirror image for comparison.

Point tenderness

tenderness that is sharply localized at the site of the injury, found by gently palpating along the bone with the tip of one finger

Guarding

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* An inability to use the extremity is the patient’s way of immobilizing it to minimize pain. 
* The muscles around the fracture contract in an attempt to prevent any movement of the broken bone.
* Guarding does not occur with all fractures; some patients may continue to use the injured part for a time.

Swelling

* Rapid swelling usually indicates bleeding from a fracture and is typically followed by substantial pain.
* Often, if the swelling is severe, it may mask deformity of the limb.
* Generalized swelling from fluid buildup may occur several hours after an injury.

Bruising

* Fractures are almost always associated with **ecchymosis** (discoloration) of the surrounding soft tissues.
* Bruising may be present after almost any injury and may take hours to develop; it is not specific to bone or joint injuries.
* The discoloration associated with acute injuries is usually redness.
* Within hours or days, blue, purple, and black discoloration will appear, followed by yellow and green.

Ecchymosis

blue or black discoloration associated with a closed wound; signifies bleeding within or under the skin; also see contusion

Crepitus

a grating or grinding sensation caused by fractured bone ends or joints rubbing together; also air bubbles under the skin that produce a crackling sound or crinkly feeling

False motion

movement that occurs in a bone at a point where there is no joint, indicating a fracture; also called free movement

Exposed fragments

* in open fractures, bone ends may protrude through the skin or be visible within the wound.
* *Never* attempt to push the end of a protruding bone back into place. This will increase the risk for infection.

Pain

* Pain, along with tenderness, bruising, and bleeding, commonly occurs in association with fractures.
* Remember to use the OPQRST mnemonic to assess pain: Onset, Provocation/palliation, Quality, Region/radiation, Severity, and Time (duration).

Locked joint

* A joint that is locked into position is difficult and painful to move.
* Crepitus and false motion appear only when a limb is moved or manipulated and are associated with injuries that are extremely painful.
* Do not manipulate the limb excessively in an effort to elicit these signs.
* This sign is more commonly the result of a soft-tissue injury within the joint (typically the knee or elbow), but the presence of a locked joint should alert you to the possibility of an underlying fracture.

Dislocation

a disruption of a joint in which the bone ends are no longer in contact

Reduce

to return a dislocated joint or fractured bone to its normal position; to set

The signs and symptoms of a **dislocated joint** are similar to those of a fracture and include:

* Marked deformity
* Swelling
* Pain that is aggravated by any attempt at movement
* Tenderness on palpation
* Virtually complete loss of normal joint 
motion (locked joint)
* Numbness or impaired circulation to the limb or digit

Sprain

when a joint is twisted or stretched beyond its normal range of motion

The supporting capsule and ligaments are stretched or torn, resulting in injury to the:

* Ligaments
* Articular capsule
* Synovial membrane
* Tendons crossing the joint

Signs and symptoms of a sprain include:

* The patient is unwilling to use the limb (guarding).
* Swelling and ecchymosis are present at the injured joint as a result of torn blood vessels.
* Pain prevents the patient from moving or using the limb normally.
* Instability of the joint is indicated by increased motion, especially at the knee; however, this may be masked by severe swelling and guarding.

Strain (pulled muscle)

a stretching or tearing of the muscle and/or tendon, causing pain, swelling, and bruising of the soft tissues in the area.

Amputation

an injury in which part of the body is completely severed

Often, the likelihood of a complication is related to the following:

* The strength of the force that caused the injury
* The injury’s location
* The patient’s overall health

Tourniquet

the bleeding control method used when a wound continues to bleed despite the use of direct pressure and elevation; useful if a patient is bleeding severely from a partial or complete amputation

Examination of the injured limb should include the 6 Ps of musculoskeletal assessment:

* Pain
* Paralysis
* Paresthesia (numbness or tingling)
* Pulselessness
* Pallor
* Pressure

Caring for musculoskeletal injuries

COMPLETE ON OWN TIME

Splint

a flexible or rigid device that is used to protect and maintain the position of an injured extremity

3 basic types of splints are:

* Rigid
* Formable
* Traction

Applying a rigid splint

There are two situations in which you must splint the limb in the position of deformity:

* When the deformity is severe
* When you encounter resistance or extreme pain when applying gentle traction to the fracture of a shaft of a long bone

Applying a zippered air splint

Applying an unzippered air splint

Applying a vacuum splint

Traction

the most effective way to realign a fracture of the shaft of a long bone so that the limb can be splinted more effectively

Several different types of lower extremity traction splints are commercially available, such as:

* Hare traction splints
* Sager splints
* Reel splints
* Kendrick splints

Do not use traction splints for:

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* Injuries of the upper extremity
* Injuries close to or involving the knee
* Injuries of the pelvis
* Partial amputations or avulsions with bone 
separation
* Lower leg, foot, or ankle injuries

Applying a hare traction splint

Applying a sager traction splint

Reel splints

* **a traction splint that is also used by the US military.**
* Many devices used in combat eventually appear in the ambulance and are used by EMTs in the field.
* This splint is designed to be used on a lower extremity.

Pelvic binders

a device to splint the bony pelvis to reduce hemorrhage from bone ends, venous disruption, and pain

Hazards associated with the improper application of splints, including:

* Compression of nerves, tissues, and blood vessels
* Delay in transport of a patient with a life-threatening injury
* Reduction of distal circulation
* Aggravation of the injury
* Injury to tissue, nerves, blood vessels, or muscles as a result of excessive movement of the bone or joint

Two instances when you should splint a limb in the position of the deformity:

1\.) When you encounter resistance or extreme pain when applying traction

2\.) When the deformity is the result of a dislocation and is severe

Acromioclavicular (AC) joint

a simple joint where the bony projections of the scapula and the clavicle meet at the top of the shoulder

Swathe

a bandage that passes around the chest to secure an injured arm to the chest

Sling

a bandage that passes around the chest to secure an injured arm to the chest

Glenoid fossa

the part of the scapula that joins with the humeral head to form the glenohumeral joint

Fracture of the distal humerus

* Also known as a supracondylar or intercondylar fracture
* Common in children
* Frequently, the fracture fragments rotate significantly, producing deformity and causing injuries to nearby vessels and nerves.
* Swelling occurs rapidly and is often severe.

Dislocation of the elbow

* Typically occurs in athletes and rarely in young children
* It can occur in toddlers when they are lifted or pulled by the arm (sometimes called “nursemaid’s elbow”), although it is not technically a joint dislocation.
* The ulna and radius are most often displaced posteriorly relative to the humerus.
* The ulna and radius join the distal humerus.
* The posterior displacement makes the olecranon process of the ulna much more prominent.
* The joint is usually locked, with the forearm moderately flexed on the arm; this position makes any attempt at motion extremely painful.
* There is swelling and significant potential for vessel or nerve injury.

Elbow joint sprain

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* This diagnosis is often mistakenly applied to an occult, nondisplaced fracture, as it can be difficult to distinguish between sprains and fractures.

Fracture of the olecranon process of the ulna

* This can result from direct or indirect forces and is often associated with lacerations and abrasions.
* The patient will be unable to actively extend the elbow.

Fracture of the radial head

* Often missed during diagnosis, this fracture generally occurs as a result of a fall on an outstretched arm or a direct blow to the lateral aspect of the elbow.
* Attempts to rotate the forearm will cause discomfort.

Splinting the hand and wrist

Goals of in-line traction?

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Stabilize the fragments to prevent movement

Avoid neurovascular compromise

Align the limb for splinting

Retroperitoneal space

the space between the abdominal cavity and the posterior abdominal wall, containing the kidneys, certain large vessels, and parts of the gastrointestinal tract

Hematuria

blood in the urine

Sciatic nerve

the largest nerve in the lower extremity; it controls the activity of muscles in the posterior thigh and below the knee and the sensation in most of the leg and foot

Compartment syndrome

swelling within a confined anatomic compartment that produces dangerous pressure, characterized by extreme pain, decreased pain sensation, pain on stretching of affected muscles, and decreased power; frequently seen in fractures below the elbow or knee in children

Musculoskeletal injuries:

* Fractures
* Dislocations
* Amputations
* Sprains
* Strains