Bone fracture
A break in bone continuity requiring medical attention.
Wikipedia / Wikimedia Commons
A bone fracture is when a bone in the body cracks or breaks completely, either partially or all the way through. In serious cases, the bone can shatter into multiple pieces—this is called a comminuted fracture. If the broken bone pierces the skin, it is known as an open or compound fracture. Fractures often happen from a strong impact or stress, but they can also occur from minor trauma if a medical condition like osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta has weakened the bone; this type is called a pathologic fracture. Urgent medical care is usually needed to avoid further damage.
**Signs and symptoms** Even though bone tissue itself lacks pain receptors, fractures hurt for several reasons. The break disrupts the periosteum (and sometimes the endosteum), both of which are rich in pain receptors. Swelling and a hematoma from nearby soft tissues, caused by ruptured bone marrow, create pressure that adds to the pain. Involuntary muscle spasms try to hold the bone fragments in place, causing more discomfort. Damage to nearby structures—like nerves, muscles, blood vessels, the spinal cord, nerve roots (in spine fractures), or cranial contents (in skull fractures)—can produce additional specific symptoms.
**Complications** Some fractures lead to serious problems, such as compartment syndrome. Without treatment, this condition may eventually require amputation of the affected limb. Other complications include non-union, where the bone fails to heal, and malunion, where it heals in a deformed shape. One type of malunion is malrotation, which is especially common after fractures of the femur or tibia. Complications are grouped by when they occur: immediate (at the time of fracture), early (within the first few days), and late (long after the fracture).
**Pathophysiology** Healing begins when the injured bone and surrounding tissues bleed, forming a fracture hematoma. This blood clots into a blood clot between the broken ends. Within days, new blood vessels grow into the clot’s jelly-like matrix, bringing phagocytes that clear away dead material. These vessels also bring fibroblasts, which multiply and produce collagen fibers, replacing the clot with a collagen matrix. Collagen’s rubbery texture allows only slight movement of the fragments unless strong or persistent force is applied. Some fibroblasts then start laying down bone matrix as c
- field
- Orthopedic medicine
- known_for
- Classification, healing process, and complications of bone fractures
- common_causes
- High force impact, stress, or minimal trauma due to conditions like osteoporosis
- healing_time
- Bone callus visible on X-ray within 6 weeks in adults; strength 80% of normal by 3 months
- complications
- Compartment syndrome, non-union, malunion
Lore & Background
A bone fracture occurs when the continuity of a bone is partially or completely broken. The injury may result from high force impact or stress, or from minimal trauma when underlying conditions such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta weaken the bone—termed a pathologic fracture. Although bone tissue lacks pain receptors, fractures are painful due to disruption of the periosteum and endosteum, edema and hematoma from ruptured bone marrow, involuntary muscle spasms, and damage to adjacent structures like nerves or blood vessels.
Reader's Guide
The natural healing process begins with a fracture hematoma, which is replaced by a collagen matrix that mineralizes into bone over weeks to months. Factors such as tobacco smoking hinder healing, while adequate nutrition and weight-bearing stress aid it. Fractures are classified by mechanism (traumatic, pathologic, periprosthetic), soft-tissue involvement (closed or open), displacement, pattern (e.g., transverse, spiral, comminuted), and anatomical location. Complications include compartment syndrome, which may require amputation, and non-union or malunion, where the bone fails to heal or heals deformed. Diagnosis relies on history, physical exam, and radiographic imaging; CT or MRI may be used when needed.
Did You Know?
- Smokers have lower bone density and a higher risk of fractures, and smoking delays bone healing.
- An open fracture carries a risk of infection up to 30%, compared to 1-2% for closed fractures.
- Healing bone callus is usually sufficiently mineralized to show on X-ray within 6 weeks in adults.
- Compartment syndrome from a fracture may eventually require amputation if untreated.
Frequently Asked Questions
What is a bone fracture?
A bone fracture is the loss of structural continuity in a bone, meaning it cracks or breaks either partially or all the way through. In severe cases the bone shatters into multiple fragments, a pattern called a comminuted fracture, and if the broken ends pierce the overlying skin the injury is termed an open or compound fracture.
What causes a bone fracture?
Most fractures result from a high-force impact or repetitive mechanical stress, but they can also occur from very minor trauma when an underlying condition such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta has already weakened the skeletal material. This latter category is specifically classified as a pathologic fracture.
How long does a bone fracture take to heal?
In adults, a visible bone callus typically appears on X-ray within about six weeks after the injury. By roughly three months the healing bone has regained around 80 percent of its original strength, though complete remodeling takes considerably longer.
What complications can a bone fracture lead to?
Serious complications include compartment syndrome, in which trapped swelling raises pressure inside a muscle compartment; non-union, where the bone fails to knit back together; and malunion, where the bone heals in a misaligned position. These outcomes often necessitate additional surgical intervention.
Why is a bone fracture considered an orthopedic emergency?
Because an untreated or improperly managed fracture can rapidly damage surrounding soft tissue, blood vessels, and nerves, urgent medical care is essential to realign the bone and prevent limb-threatening or life-threatening sequelae. Orthopedic medicine is the specialty dedicated to classifying, stabilizing, and managing the long-term healing of these injuries.
More in Surgery & Trauma 1-24
Spotted an error? Know more?
This is a living reference — every entry is fact-audited, and reader corrections feed straight into our audit queue. Suggest an edit · See this site's audit record