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(For vertebral compression fractures, see Osteoporosis: Secondary osteoporosis; for dental fractures, see Dental Emergencies: Fractured and Avulsed Teeth; for spinal fractures, see Spinal Trauma; for fractures of the temporal bone, jaw and contiguous structures, and nose, see Facial Trauma: Fractures of the Nose; for metatarsal stress fractures, see Sports Injury: Stress Fractures; for orbital fractures, see Eye Trauma: Blowout fracture, and for fractures that occur during birth, see Perinatal Problems: Fractures.)
Fractures are cracks in bones. Symptoms include pain, swelling, ecchymosis, crepitation, deformity, and abnormal motion. Occasional complications include fat embolism, arterial injury, compartment syndrome, nerve injuries, and infection. Diagnosis is by clinical criteria and usually plain x-rays. Treatment involves analgesics, immobilization, and sometimes surgery.
Most fractures result from a single application of significant force to otherwise normal bone. Pathologic fractures result from application of mild or minimal force to a bone weakened by a disorder such as cancer, cysts, or osteoporosis. Stress fractures (eg, metatarsal stress fracture—see Sports Injury: Stress Fractures) result from repetitive application of force.
Pathophysiology
If Ca and vitamin D levels are adequate and bone tissue is healthy and the fracture edges are kept reasonably close to each other and with little or no relative motion, most fractures heal within weeks or months via remodeling. New tissue (callus) is produced within weeks, and bone reshapes at variable rates during the first weeks or months. Ultimately, optimal remodeling requires gradual resumption of normal motion and load-bearing stress. However, remodeling can be disrupted and refracture can occur if force is applied or the joint moves prematurely; thus, immobilization is usually needed.
Serious complications are unusual. Arteries are injured occasionally in closed supracondylar fractures of the humerus and femur but rarely in other closed fractures. Compartment syndrome or nerve injury may occur. Open fractures predispose to bone infection (see Infections of Joints and Bones: Osteomyelitis), which can be intractable. Fractures of long bones may release fat (and other marrow contents) that embolizes to the lungs and causes respiratory complications (see Sidebar 1: Pulmonary Embolism: Nonthrombotic Pulmonary Embolism ). Fractures that extend into joints usually disrupt articular cartilage; misaligned articular cartilage tends to scar, causing osteoarthritis and impairing joint motion. Occasionally, fractures do not heal (called nonunion); rarely, nonunion occurs even when treatment is expeditious and correct. If the vascular supply is injured by the initial injury (such as a scaphoid fracture), aseptic necrosis may ensue even if the fracture was properly immobilized.
Symptoms and Signs
Pain is usually immediate. Swelling increases for several hours. Children may not exhibit significant soft-tissue swelling in the presence of a fracture (buckle [torus] fracture or greenstick fracture). Pain and swelling usually begin to resolve after 12 to 24 h; worsening pain after this period suggests compartment syndrome. Other symptoms and signs may include bone tenderness, ecchymosis, decreased or abnormal motion, deformity, and crepitation. With some fractures (eg, rib fractures), motion can be sensed by the patient and is described as a popping or cracking sensation.
Diagnosis
Patients with findings that suggest fracture are examined for ischemia, compartment syndrome, and nerve injury. If a wound is close to a fracture, open fracture is assumed. Fractures are diagnosed by imaging, beginning with plain x-rays. If no fracture line is obvious, bone density, trabecular pattern, and cortical margins are examined for subtle clues to fracture. If a fracture is not visible on plain x-rays but is strongly suspected or if more detail is needed to guide treatment, MRI or CT is done. Some experts recommend imaging the joints proximal and distal to the fracture.
A fracture's appearance on x-rays can be described precisely using 5 terms:
Location may be the bone's head (sometimes involving the articular surface), neck, or shaft (proximal, middle, or distal third).
Treatment
Immediate treatment includes analgesics and, for suspected unstable fractures or fractures of long bones, splinting. Suspected open fractures require sterile wound dressings, tetanus prophylaxis, and broad-spectrum antibiotics (eg, a 2nd-generation cephalosporin plus an aminoglycoside).
Rotational malalignment or significant angulation or displacement is corrected with reduction (realignment of bone fragments by manipulation). Exceptions include some diaphyseal fractures in children. In these fractures, remodeling gradually corrects some types of significant angulation, and end-to-end realignment of fractured bone fragments can stimulate bone growth, which may then be excessive.
Closed reduction (without skin incision) is done when possible; if not, open reduction (with skin incision) is done.
In open reduction and internal fixation (ORIF), fracture fragments are aligned and held in place using hardware. ORIF is usually indicated for the following:
Surgery is required when injury to a major vessel is suspected (for vessel repair) or when the fracture is open (for irrigation and debridement to prevent infection). Open reduction may be done without using hardware when closed reduction is ineffective.
Fractures, whether they require reduction, surgery, or neither, are typically immobilized, as are the proximal and distal joints. Usually, a cast is applied for weeks or months, but a splint may be used instead, particularly for fractures that heal faster when mobilized early. Home care for fractures includes supportive measures such as RICE (rest, ice, compression, elevation—see Fractures, Dislocations, and Sprains: RICE).
Patients are told to seek care immediately if symptoms of compartment syndrome occur (see Fractures, Dislocations, and Sprains: Compartment Syndrome).
Geriatrics Essentials
The elderly are predisposed to fractures because of osteoporosis, a tendency to fall frequently, drug adverse effects, and impaired protective reflexes during falls. Age-related fractures tend to affect the metaphysis (the flared area between the end and shaft). They include fractures of the distal radius, proximal humerus, proximal tibia, proximal femur, pubic ramus, and vertebrae.
The goal of treatment is rapid return to activities of daily living rather than restoration of perfect limb alignment and length. Because immobilization (joint immobilization or bed rest) is more likely to cause adverse effects in the elderly, use of ORIF is increasing. Early mobilization and physical therapy are essential to recovery of function. Coexisting disorders (eg, arthritis) can interfere with recovery.
Specific Fractures
Stress fractures:
Stress fractures are small and result from repetitive force (eg, from overuse); they occur most often in the metatarsals (usually in runners—see Sports Injury: Stress Fractures), followed by the fibula and tibia. Symptoms include gradual onset of intermittent pain that worsens with weight bearing and eventually becomes constant. Sometimes swelling occurs.
Examination detects localized bone tenderness. Plain x-rays are done but may not show the fracture at first. Thus, many such fractures are treated presumptively, and plain x-ray is repeated 2 to 3 wk later when callus may be visible. Treatment is rest, elevation, analgesics, and sometimes immobilization. CT or MRI is rarely needed.
Growth plate fractures:
Bone grows as tissue is added proximally by the epiphyseal disk (growth plate), which is bordered by the metaphysis proximally and the epiphysis distally (see Fig. 4: Fractures, Dislocations, and Sprains: Epiphyseal disks (growth plates). ). The age at which the growth plate closes and bone growth stops varies by bone, but the growth plate is closed in all bones by the end of puberty. If there is question about a growth plate injury or if a fracture is suspected, opposite side comparison x-rays may be helpful.
The growth plate is the most fragile part of the bone and thus is usually the first structure disrupted when force is applied. Growth plate fractures are classified by the Salter-Harris system (see Fig. 5: Fractures, Dislocations, and Sprains: Salter-Harris classification of epiphyseal disk (growth plate) fractures.). Disruption of future bone growth is common with types III, IV, and V but uncommon with types I and II.
Growth plate fractures are suspected in children with tenderness localized over the growth plate. These fractures cause circumferential tenderness and thus can be clinically differentiated from contusions. In fracture types I and V, x-rays may appear normal. If so, these fractures can sometimes be differentiated from each other by injury mechanism—eg, distraction (separation in longitudinal axis) vs compression.
Closed treatment is usually sufficient for types I and II; ORIF is often required for types III and IV. Patients with type V injuries should be referred to a pediatric orthopedist because such injuries almost always lead to growth abnormalities.
Rib fractures:
Typically, rib fractures result from blunt injury to the chest wall, usually involving a strong force (eg, from high-speed deceleration, a baseball bat, a major fall); however, sometimes in the elderly, only mild or moderate force (eg, in a minor fall) is required. Concomitant injuries may include
Pain is severe, is aggravated by movement of the trunk (including coughing or deep breathing), and lasts for several weeks. Inspiratory splinting (incomplete inspiration due to pain) can cause atelectasis and pneumonia, especially in the elderly or those with multiple fractures. Young, healthy patients and those with 1 or 2 rib fractures rarely develop these complications.
Palpation of the chest wall may identify some fractures, and sometimes the patient and the examining clinician can feel the broken ribs move when the lungs are expanded. A chest x-ray is taken routinely to check for concomitant injuries (eg, pneumothorax, pulmonary contusion). Many rib fractures are not visible on a chest x-ray; specific rib views may be needed, but identifying all rib fractures by x-rays is not always necessary. Other tests are done to check for concomitant injuries that are clinically suspected.
Treatment requires opioid analgesics, which can depress respiration and worsen atelectasis. To minimize pulmonary complications, patients should consciously and frequently (eg, hourly) breathe deeply or cough while awake. Holding (essentially splinting) the affected area with the flat palm of the hand or a pillow can help minimize the pain during deep breathing or coughing. Patients are hospitalized if they have ≥ 3 fractures or underlying cardiopulmonary insufficiency. Immobilization (eg, by strapping or taping) should usually be avoided; it constricts respiration and may predispose to atelectasis and pneumonia.
Clavicle fractures:
The usual injury mechanism is a fall on an outstretched arm or a direct blow. About 80% involve the middle 1⁄3 of the bone and are immobilized with a sling. Previously used figure-of-eight braces are no more helpful (and are more uncomfortable) than a simple sling. Reduction is not necessary even for greatly angulated fractures. Clavicle fractures that significantly tent the skin or that involve areas other than the middle 1⁄3 of the bone may require additional intervention.
Proximal humeral fractures:
The usual injury mechanism is direct force or a fall on an outstretched arm. Usually, displacement and angulation are minimal. Contractures may develop after only a few days of immobilization, particularly in the elderly. Minimally displaced or angulated fractures are treated with immobilization in a sling and swathe (see Fig. 1: Fractures, Dislocations, and Sprains: Joint immobilization as acute treatment: some commonly used techniques.) and early range-of-motion exercises. More severe fracture may require ORIF or surgery to insert a prosthetic joint (shoulder replacement).
Distal humeral fractures:
The usual injury mechanism is direct force or a fall on an outstretched arm. The brachial artery or radial nerve may be damaged. Angulation, if present, must be corrected. Casting with closed reduction may be tried, but ORIF may be necessary.
Radial head fractures:
The usual injury mechanism is a fall on an outstretched arm. The radial head is palpated on the lateral elbow as a structure that rotates during pronation and supination. Routine anteroposterior and lateral x-rays usually show a joint effusion or a displaced anterior fat pad (sail sign) but often do not show the fracture. Patients with localized radial head tenderness and effusion require oblique views (which are more sensitive for fracture) or presumptive treatment of a fracture. For fractures with only minimal angulation and displacement, treatment is a splint with the elbow flexed 90° or a sling. Arthrocentesis to remove blood from the joint often helps relieve pain and facilitate recovery. Starting range-of-motion exercises 10 days after the injury maximizes joint flexibility.
Distal radial fractures:
The usual injury mechanism is wrist hyperextension, usually during a fall. Dorsally displaced or angulated fractures (sometimes called Colles' fractures) are common. Treatment is reduction and immobilization at 15 to 30° of wrist extension. ORIF may be necessary if the joint is disrupted or if there is excessive impaction or shortening.
Metacarpal neck fractures (except thumb):
The usual injury mechanism is an axial load (eg, from punching with a clenched fist). If wounds are near the metacarpophalangeal joint, contamination with human oral flora should be considered, and measures to prevent infection are often required (see Bites and Stings: Antimicrobials). Reduction is necessary for fractures of the 2nd and 3rd metacarpals but is unnecessary for dorsal or volar angulation of < 35° for the 4th metacarpal or of 45° for the 5th metacarpal. Treatment is a splint (eg, an ulnar gutter splint for fractures of the 4th or 5th metacarpal—see Fig. 1: Fractures, Dislocations, and Sprains: Joint immobilization as acute treatment: some commonly used techniques.).
Scaphoid (navicular) fractures:
The usual injury mechanism is wrist hyperextension, usually during a fall on the outstretched hand. Avascular necrosis is a common complication, even when initial care is ideal, and can cause disabling, degenerative arthritis of the wrist. Fracture signs include pain with axial compression of the thumb, pain with wrist supination against resistance, and, particularly, tenderness in the anatomic snuffbox with ulnar wrist deviation. The anatomic snuffbox is palpated just distal to the radius between the extensor pollicis longus, extensor pollicis brevis, and abductor pollicis longus tendons. The initial plain x-ray is often normal. If a fracture is still suspected, MRI, which is more sensitive than x-rays, is done, or fracture is presumed and treated with a thumb spica splint see Joint immobilization as acute treatment: some commonly used techniques, with a follow-up plain x-ray taken in 1 to 2 wk. Rarely, this subsequent x-ray is falsely normal.
Fingertip (tuft of the distal phalanx) fractures:
The usual mechanism is a crush injury. Subungual (beneath the nail) hematoma usually occurs and produces a blue-black, tender bruise, which may elevate the nail; hematoma indicates a nail bed laceration. Most fingertip fractures are treated symptomatically with a protective covering (eg, commercially available aluminum and foam splint material) wrapped around the fingertip. Subungual hematomas can be drained to relieve pain by puncturing the nail (trephination), usually with an 18-gauge needle in a rotatory motion or, if no nail polish is on the nail, with an electrocautery device. If trephination is done gently and rapidly, anesthesia is often unnecessary. Large displaced fractures are rarely repaired surgically. Markedly disrupted nail beds are repaired with sutures but are best left alone if the nail is closely adherent to the nail bed. Hyperesthesia frequently persists long after a large fracture has healed and requires desensitization therapy.
Pelvic fractures:
Pelvic fractures may be stable or unstable. Compression of the pubic symphysis or simultaneous compression of both anterior superior iliac spines is often painful, particularly in severe fractures. For pelvic fractures, CT is more sensitive than plain x-rays.
Stable fractures do not disrupt the pelvic ring. Some (eg, symphyseal or pubic ramus fractures) result from minor injuries (eg, falls at home), especially in patients with osteoporosis. Treatment is often symptomatic, particularly if patients can walk unaided.
Unstable fractures disrupt the pelvic ring in ≥ 2 places; disruptions can be fractures within bones or separations between the fibrous joints (syndesmoses) between bones. Unstable fractures usually result from substantial forces (eg, high-speed motor vehicle crashes). Intestinal injuries may occur. Concomitant GU injuries (eg, urethral or bladder tears) are common, particularly with anterior pelvic fractures. Vascular injuries may occur and cause hemorrhagic shock, especially with posterior pelvic fractures. Mortality rate is high. Initial evaluation and treatment are directed at associated injuries. The fracture often requires surgical repair.
Hip fractures:
Hip fractures are most common among the elderly, particularly those with osteoporosis (mostly women—see Osteoporosis). Most fractures result from falls, but in the elderly, seemingly minimal force (eg, rolling over in bed, getting up from a chair, walking) can result in hip fracture, usually because osteoporosis has weakened bone. Subcapital femoral neck and intertrochanteric fractures are the most common types. Hip fractures often cause referred pain in the knee and thus may be misinterpreted as a knee abnormality. Pubic ramus fractures can cause hip pain.
Subcapital fractures may result from a single injury but often result from repeated stress or minimal force, resulting in a small or large stress fracture. A fall after the initial fracture may worsen or displace the fracture. Patients with small fractures may be ambulatory and have only mild pain. However, such patients may be unable to flex the entire lower limb against resistance with the knee extended. Passive hip rotation with the knee flexed aggravates the pain, helping to differentiate hip fracture from extra-articular disorders such as trochanteric bursitis. Large or displaced fractures tend to limit hip motion more, shorten the leg, and cause the leg to rotate externally. Displacement predisposes to osteonecrosis of the femoral head and fracture nonunion.
Plain x-rays are occasionally normal when fractures are small or impacted or when osteoporosis is severe. If a fracture is still suspected, MRI is done; if MRI is unavailable or contraindicated, CT is done. If patients are expected to resume walking and have no contraindication to surgery, treatment is usually surgical repair (typically ORIF—see Fig. 6: Fractures, Dislocations, and Sprains: Open reduction with internal fixation (ORIF).) and early ambulation.
If patients are elderly, are not active, and have displaced fractures, treatment is often prosthetic replacement of the femoral head, typically with a Moore prosthesis, or total hip replacement. Occasionally, the femoral head must be replaced when the fracture is displaced in younger adults, particularly those who are inactive. Usually, prolonged bed rest should be avoided in elderly patients. Bed rest increases the risk of deep venous thrombosis, a common complication of hip fractures. Prophylactic anticoagulation may reduce the incidence of post−hip fracture venous thrombosis.
Intertrochanteric fractures usually result from falls or direct blows. Patients have tenderness, ecchymosis, and swelling over the hip; usually, the leg is shortened and rotates externally. Plain x-rays are usually diagnostic. Treatment is usually ORIF and early mobilization.
Femoral shaft fractures:
The usual injury mechanism is severe direct force or an axial load to the flexed knee. Fracture due to trauma causes obvious swelling, deformity, and instability. Up to 1.5 L of blood for each fracture may be lost. Treatment is immediate splinting, then ORIF.
Ankle fractures:
The ankle bones and ligaments form a ring that connects the tibia and fibula to the talus and calcaneus. Within the ring, stability is provided by 2 bones (the medial malleolus of the tibia and lateral malleolus of the fibula) and 2 ligament complexes (medially, the deltoid ligament; laterally, mainly the anterior and posterior talofibular ligaments and calcaneofibular ligament—see Fig. 7: Fractures, Dislocations, and Sprains: Ligaments of the ankle.). Ankle fractures are common and can result from multiple injury mechanisms. Fractures that disrupt the ring in one place often disrupt it in another (eg, if only one bone is fractured, a ligament is often simultaneously and severely torn). If fractures disrupt ≥ 2 of the structures stabilizing the ankle ring, the ankle is unstable. Disruption of the medial deltoid ligament also causes instability. For unstable injuries, surgery may be required, and prognosis is guarded. Most stable ankle fractures without other indications for surgery can be treated with a cast for 6 wk; prognosis is good.
Fractures of the 2nd metatarsal bone base with dislocation (Lisfranc's fracture-dislocation):
The usual mechanism is a fall on a foot in plantar flexion. Usually there is significant soft-tissue swelling. These rare fractures are difficult to appreciate on plain x-rays and are often misdiagnosed, leading to sometimes serious complications, such as osteoarthritis and rarely compartment syndrome. A plain x-ray can show a fracture at the base of the 2nd metatarsal or chip fractures of the cuneiform but may not show disruption of the tarsometatarsal joint, which should be suspected even if it is not visible on plain x-rays. Dislocations often spontaneously reduce, but immediate referral, usually for closed reduction, which requires general anesthesia, may be warranted.
Fractures of the 5th metatarsal bone base (dancer's fracture):
The usual injury mechanism is a twist (typically, inversion) or crush injury. These fractures usually heal relatively quickly; nonunion is uncommon. Treatment is a protective walking shoe.
Fractures of the 5th metatarsal bone diaphysis (Jones fracture):
The usual injury mechanism is a crush injury. These fractures are less common than those of the metatarsal bone base, and delayed union or nonunion occurs more commonly. Treatment is a cast that immobilizes the ankle. Avulsion fractures of the base of the fifth metatarsal can occur with inversion ankle injuries and are less significant than a true Jones fracture, the latter being predisposed to nonunion.
Toe fractures:
The usual injury mechanism is a crush injury. Unless rotational deformity or joint involvement is suspected or the proximal phalanx of the great toe is injured, x-rays are usually unnecessary. Treatment is taping the injured toe to an adjacent toe (dynamic splinting or buddy taping). Markedly displaced toe fractures should be reduced to restore alignment.
Last full review/revision October 2007 by James R. Roberts, MD
Content last modified February 2012
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