Introduction
A fracture is a break in a bone, usually accompanied by injury to the surrounding tissues.
Fractures vary greatly in size, severity, and the treatment needed. They can range from a small, easily missed crack in a hand bone to a massive, life-threatening break of the pelvis. Serious injuries, including injuries to the skin, nerves, blood vessels, muscles, and organs, may occur at the same time as the fracture. These injuries can complicate treatment of the fracture.
Trauma is the most common cause of fractures. Low-energy trauma, such as a fall on level ground, usually causes minor fractures. High-energy trauma, such as high-speed motor vehicle accidents and falls from buildings, can cause severe fractures that involve several bones.
Certain underlying disorders can weaken parts of the skeleton so that breaks are more likely to occur. Such disorders include certain infections, benign bone tumors, cancer, and osteoporosis.
Symptoms and Complications
Pain is the most obvious symptom. Fractures hurt, especially when force is applied, such as when a person tries to put weight on an injured limb. The area around the broken bone is also tender to touch. Swelling of soft tissue around the fracture begins within a few hours. The limb may not function properly, so that moving an arm, standing on a leg, or gripping with a hand is very painful. For a person who cannot speak (for example, a very young child, a person with a head injury, or an older person with dementia), refusal to move an extremity may be the only sign of a fracture. People with pathologic fractures often experience steadily increasing pain beginning weeks before the fracture actually occurs.
Internal bleeding may occur with a closed fracture (one in which the skin is not torn). The bleeding may occur from the bone itself or from surrounding soft tissues. The blood eventually works its way to the surface, forming a bruise, which at first is purplish-black then slowly turns to green and yellow as the blood is broken down and reabsorbed back into the body. The blood can move quite a distance from the fracture, and the entire process takes a few weeks to complete. The blood can cause temporary pain and stiffness in surrounding structures. Shoulder fractures, for instance, can bruise the entire arm and cause pain in the elbow and wrist. Some fractures, especially hip fractures, can lose quite a lot of blood into the surrounding tissues, causing low blood pressure.
The person usually feels some discomfort with activities even after fractures have healed sufficiently to allow full weight bearing. For example, although a fractured wrist may be strong enough to allow some use in about 2 months, the wrist will not have completely undergone remodeling, and it will be painful with forceful gripping for up to 1 year. The person may also notice increased pain and stiffness when the weather is damp, cold, or stormy.
Most fractures heal with few problems. However, sometimes even with proper treatment, fractures can cause serious complications.
 See the sidebar How Bones Heal.
Compartment Syndrome: Compartment syndrome is a serious limb-threatening condition caused by excessive swelling of injured muscles, which may occur as a result of a fracture or crush injury to a limb. Muscles are surrounded by a fibrous covering that forms a closed space (compartment). An injured muscle swells; when the swelling is significantly confined by the muscle's compartment, and particularly when it is further confined by a cast, the pressure within the muscle tissue may increase. This increase in pressure decreases the normal blood flow that provides oxygen to the muscle. When the muscle is deprived of oxygen for too long, further injury to the muscle occurs, which leads to further swelling and higher tissue pressures. After only a few hours, irreversible injury and death of muscle and nearby soft tissues may result.
A doctor becomes concerned about compartment syndrome when the person feels increasing pain in an immobilized limb after a fracture, pain when the fingers of an immobilized arm or toes of an immobilized leg are moved gently, or numbness in the limb. The diagnosis of compartment syndrome can be confirmed using a device that measures pressure in the muscles.
Pulmonary Embolism: Pulmonary embolism is the sudden blocking of a lung artery by an embolus, nearly always resulting from a blood clot that can travel to the lungs, especially from the deep veins of the leg (see Section 4, Chapter 46). Pulmonary embolism is the most common fatal complication of serious hip and pelvic fractures. People with hip fractures are at high risk of pulmonary embolism because of the combination of trauma to the leg, forced immobilization for hours or days, and swelling around the fracture site blocking blood flow in the veins. Of people with a hip fracture who die, about one third die of pulmonary embolism. Pulmonary embolism occurs much less commonly with fractures of the lower leg and very rarely with fractures of the upper body.
Doctors may suspect pulmonary embolism based on a range of symptoms, including chest pain, cough, and shortness of breath. Confirmation may involve chest x-ray, electrocardiogram, and one or more of a variety of imaging studies.
Diagnosis
X-rays are the most important tool for diagnosing a fracture. They not only show the fracture but also help a doctor understand how the fragments of bone are misaligned. Small or nondisplaced fractures can be difficult to see on routine x-rays, and sometimes additional x-rays are taken at special angles. Occult or stress fractures may take days or weeks to show clearly on x-rays. Pathologic fractures are diagnosed by x-rays that show bone abnormalities, such as punched-out (lytic) areas caused by infection, benign tumors, or cancer.
Computed tomography (CT) and magnetic resonance imaging (MRI) can show features not seen on routine x-rays. CT can show the fine details of a fractured joint surface or can reveal areas of a fracture hidden by overlying bone. MRI shows the soft tissue around the bone, which helps to detect injury to nearby tendons and ligaments, and can show evidence of cancer. MRI also shows injury (swelling or bruising) within the bone and can thus reveal occult fractures before they appear on x-rays.
Bone scanning (see Section 5, Chapter 59) is an imaging procedure that involves use of a radioactive substance (technetium-99m-labeled pyrophosphate) that is taken up by any healing bone. Occult fractures can be detected on bone scans 3 to 5 days after the injury. If a pathologic fracture is suspected, bone scans help to check for problems in other bones--ones that might not yet be producing symptoms.
Treatment
Fractures require immediate attention because they cause pain and loss of function for the person. After initial emergency care, fractures usually require further treatment, including immobilization with casts or traction, or fixation with surgery.
Fractures in children are often treated differently than those in adults because bones in children are smaller, more flexible and less brittle, and most importantly, still growing. Treatment with casts or traction is often preferred over surgery to avoid damage to the growth plate.
 See the table Types of Fractures.
Initial Treatment: When a fracture is suspected, the person should call his or her doctor, who will determine the appropriate facility for treatment. The choice of a facility depends on the severity of the injury. For example, people with minor wrist and shoulder fractures can be treated in medical offices. Because people with hip fractures are in severe pain and are unable to move, they must be transported by ambulance to a hospital with surgical facilities.
Open fractures need to be treated immediately with surgery to carefully clean and close the wound. Massive open fractures with great losses of the skin, muscle, and blood supply to the bone are the most serious and difficult to treat.
For most closed fractures, treatment with casts or surgery can be delayed up to 1 week without affecting the long-term result. However, there is usually no advantage to waiting, because until they are treated, people are troubled by pain and loss of function. Before seeing a doctor, the person should immobilize and support the injured limb with a makeshift splint, sling, or a pillow; elevate the limb to the level of the heart to limit swelling; apply ice to control pain and swelling; and take only acetaminophen to relieve pain. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) should not be taken because they may worsen bleeding (see Section 6, Chapter 78).
The doctor may recommend the person continue to keep an injured arm or leg elevated to control swelling. For arm fractures, pillows are used for elevation. For leg fractures, the person should periodically lie flat with the leg on a pillow. The doctor compares the swelling of the injured limb with the normal appearance of the uninjured limb to help determine how long or often elevation is needed. During the later stages of healing, elastic stockings may be used during the daytime to help control swelling when the person is sitting or standing.
Immobilization: Most fractures can be treated without surgery. They are immobilized with a splint, sling, or cast until they heal sufficiently. Displaced fractures must be aligned (by a procedure called reduction) before being immobilized. When minor fractures (such as those of the fingers or wrist) are aligned, the person may need an injection of a local anesthetic, such as lidocaine, to prevent pain. When major fractures of the arm, shoulder, or lower leg are aligned, the person may need general or spinal anesthesia; this procedure is called closed reduction.
A splint is a long, narrow slab of plaster or fiberglass applied with elastic wrap or tape. The slab does not completely encircle the limb, which allows for some expansion due to tissue swelling. For this reason, splints are often used for initial treatment of fractures. For finger fractures, aluminum splints covered with foam are commonly used.
A sling by itself provides sufficient support for many shoulder and elbow fractures. The weight of the arm pulling downward helps to keep many shoulder fractures well aligned. A strap passing around behind the back can be added to keep the arm from swinging outward, especially at night. Slings permit some use of the hand.
A cast is made by wrapping rolls of plaster or fiberglass strips that harden once wetted. Plaster is often chosen for the initial cast when a displaced fracture is being treated. It molds well and has less of a tendency to cause painful contact points between the body and cast. Otherwise, fiberglass has the advantage of being stronger, lighter, and more durable. In either case, the cast is lined with soft cottony material to protect the skin from pressure and rubbing. If the cast becomes wet, it is often impossible to completely dry the lining; this can lead to skin softening and breakdown (maceration). For partially healed fractures, a special, more expensive and less protective waterproof lining is sometimes substituted.
After a cast is applied (especially for the first 24 to 48 hours), it should be kept elevated when possible to the level of the heart to combat swelling. Regular flexion and extension of the fingers or wiggling of the toes helps the blood to drain from the limb and also helps to prevent swelling. Pain, pressure, or numbness that remains constant or worsens over time should be reported to a doctor immediately. These conditions may be due to a developing bedsore or compartment syndrome.
See the sidebar Taking Care of a Cast.
Traction: Traction is sometimes used to keep the bones aligned while a fracture heals. An array of ropes, pulleys, and weights are used to continuously pull on the limb. In adults, traction is used only until the fracture can be safely treated with a cast or surgery. In children, certain fractures are best treated with traction because the healing time is shorter than in adults. Also, traction does not injure the growth plate, whereas surgery may do so.
Surgical Treatment: Fractures sometimes require surgical treatment. For instance, the doctor must explore and carefully clean open fractures to ensure that no foreign material has contaminated the bone ends. When a bone fragment or a tendon is trapped in the bone ends, a doctor may not be able to align a displaced fracture and surgery is needed. Comminuted fractures are often too unstable for a cast to maintain alignment against the forces of muscle contraction, which can cause the bone to shorten or angle. Joint fractures require a near-perfect alignment of the joint surfaces or the person will later develop arthritis. If possible, pathologic fractures are stabilized surgically before they break through completely. This approach avoids the pain, disability, and the more complex surgery involved with a displaced fracture. Finally, if fractures of the femur (thighbone), which includes most hip fractures, are not treated surgically, they would require months of immobilization in bed before the person is strong enough to bear weight. In contrast, surgical stabilization usually permits the person to walk with crutches or a walker within days.
Surgical stabilization involves first accurately reducing the fracture to restore the bone's original shape and length. The surgeon uses anesthesia to relax the muscles and x-ray equipment to help align the bones. A surgeon exposes the fracture to see and manipulate the fragments with special instruments. Then, the bone fragments are securely fixed using some combination of metal wires, pins, screws, rods, and plates. Metal plates are contoured and fixed to the outside of the bone with screws. Metal rods are inserted from one end of the bone into the marrow cavity. These implants are made of stainless steel, high-strength alloy metal, or titanium. All such implants made in the last 15 years are compatible with the strong magnets that are used for magnetic resonance imaging (MRI). Most will not set off security devices at airports.
A joint replacement procedure (arthroplasty) may need to be performed when fractures severely damage the upper end of the femur (thighbone) or humerus (armbone) that form the outer half of the hip and shoulder joints.
Bone grafting may be used to assist healing of fractures initially, if the gap between fragments is too large, or later, if the healing process has slowed (delayed union) or stopped (nonunion).
Treatment of Complications: For compartment syndrome, initial treatment consists of immediately removing or loosening anything that may be confining the limb, such as a splint or a cast. When the muscle compartment continues to cause increased pressure, an emergency surgery called fasciotomy must be performed to open this constricting tissue. Otherwise, the muscles and nerves could die because of a lack of oxygen. If this occurs, it may be necessary to amputate the limb.
Pulmonary embolism can be prevented with drugs such as heparin, low-molecular-weight heparin, warfarin, and fondaparinux (a new drug similar to heparin). These drugs reduce the tendency of the blood to clot, and are given to people with fractures that put them at risk of forming a pulmonary embolism. If an embolus occurs, emergency treatment is needed (see Section 4, Chapter 46).
Rehabilitation and Prognosis
Children's fractures heal much faster and more perfectly than adult fractures do. Several years after most fractures in children, the bone can look almost normal on x-ray. In addition, children develop less stiffness with cast treatment and are more likely to regain normal motion if a fracture involves a joint.
Healing in older people is often slower than in younger adults. Fractures significantly impair an older person's ability to perform normal daily activities. Diminished strength, flexibility, and balance can impair a person's independence in eating, dressing, bathing, and even walking (if the person is dependent on a walker). Nonuse of muscles can lead to stiffness, weakness, and further impairment. Nurses and caregivers must assist older people in regaining their ability to perform normal daily activities.
Older people with poor circulation are at risk for bedsores when an injured limb rests on the cast (see Section 3, Chapter 34). The areas in which the skin is in contact with the cast (contact points)--especially the heels--should be padded and inspected diligently for any sign of skin breakdown. Nurses and caregivers should be sure an older person periodically changes position to avoid stiffness. For example, prolonged sitting can lead to the hip and knee becoming fixed in a bent position. Periods of standing and walking or, in someone who is bedridden, lying down supine with the legs straight, alternating with periods of sitting with the knees bent, can help to prevent stiffness.
After surgery, people with leg fractures usually start walking with crutches or a walker for a time. Sometimes supplemental casting is needed as well. Healing time varies from days to weeks to months, depending on the nature of the fracture. People with arm fractures have similar initial activity restrictions.
Stiffness and loss of strength are natural consequences of immobilization. A joint of a fractured limb immobilized in a cast becomes progressively stiffer each week, eventually losing its ability to fully extend and flex. Wasting away of muscle (atrophy) also can be severe. For instance, after wearing a long leg cast for a few weeks, most people can insert their hand into the formerly tight space between the cast and their thigh. When the cast is removed, the weakness resulting from muscle atrophy is very apparent.
Daily exercise using range-of-motion and muscle-strengthening exercises (see Section 1, Chapter 7) helps to combat stiffness and regain strength. While the fracture is healing, the joints outside the cast can be exercised. The joints within the cast cannot be exercised until the fracture has healed sufficiently and the cast can be removed. When exercising, the person should pay attention to how the injured limb feels and avoid exercising too forcefully. Passive exercises (in which a therapist applies external force (see Section 1, Chapter 7)) must be used when muscles are too weak for effective motion and when strong muscle contractions might displace a fracture. Ultimately, active exercise (in which the person uses his own muscle force) against gravity or weight resistance is necessary to regain full strength of an injured limb.
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