Open fracture
An open fracture, also called a compound fracture, is a type of bone fracture that has an open wound in the skin near the fractured bone. The skin wound is usually caused by the bone breaking through the surface of the skin. An open fracture can be life threatening or limb-threatening due to the risk of a deep infection and/or bleeding. Open fractures are often caused by high energy trauma such as road traffic accidents and are associated with a high degree of damage to the bone and nearby soft tissue. Other potential complications include nerve damage or impaired bone healing, including malunion or nonunion. The severity of open fractures can vary. For diagnosing and classifying open fractures, Gustilo-Anderson open fracture classification is the most commonly used method. This classification system can also be used to guide treatment, and to predict clinical outcomes. Advanced trauma life support is the first line of action in dealing with open fractures and to rule out other life-threatening condition in cases of trauma. The person is also administered antibiotics for at least 24 hours to reduce the risk of an infection.
Cephalosporins, sometimes with aminoglycosides, are generally the first line of antibiotics and are used usually for at least three days. Therapeutic irrigation, wound debridement, early wound closure and bone fixation core principles in management of open fractures. All these actions aimed to reduce the risk of infections and promote bone healing. The bone that is most commonly injured is the tibia and working-age young men are the group of people who are at highest risk of an open fracture. Older people with osteoporosis and soft-tissue problems are also at risk.
Epidemiology
Crush injuries are the most common form of injuries, followed by falls from standing height, and road traffic accidents. Open fractures tend to occur more often in males than females at the ratio of 7 to 3 and the age of onset of 40.8 and 56 years respectively. In terms of anatomy location, fractures of finger phalanges are the most common one at the rate of 14 per 100,000 people per year in the general population, followed by fracture of tibia at 3.4 per 100,000 population per year, and distal radius fracture at 2.4 per 100,000 population per year. Infection rates for Gustilo Grade I fractures is 1.4%, followed by 3.6% for Grade II fractures, 22.7% for Grade IIIA fractures, and 10 to 50% of Grade IIIB and IIIC fractures.Signs and symptoms
There are a range of characteristics of open fractures as the severity of the injury can vary greatly. Most open fractures are characterized by a broken bone that is sticking out of the skin, but there can also be a broken bone that is associated with a very small "poke-hole" skin wound. Both of these injuries are classified as open fractures. Some open fractures can have significant blood loss. Most open fractures have extensive damage to soft tissues near and around the bone such as nerves, tendons, muscles, and blood vessels.Causes
Open fractures can occur due to direct impacts such as high-energy physical forces, motor vehicular accidents, firearms, and falls from height. Indirect mechanisms include twisting and falling from a standing position. These mechanisms are usually associated with substantial degloving of the soft-tissues, but can also have a subtler appearance with a small poke hole and accumulation of clotted blood in the tissues. Depending on the nature of the trauma, it can cause different types of fractures:Common fractures
s result from significant trauma to the bone. This trauma can come from a variety of forces – a direct blow, axial loading, angular forces, torque, or a mixture of these. There are various fracture types, including closed, open, stress, simple, comminuted, greenstick, displaced, transverse, oblique.Pathological fractures
Result from minor trauma to diseased bone. These preexisting processes include metastatic lesions, bone cysts, advanced osteoporosis, etc.Fracture-dislocations
Severe injury in which both fracture and dislocation take place simultaneously.Gunshot wounds
Caused by high-speed projectiles, they cause damage as they go through the tissue, through secondary shock wave and cavitation.Diagnosis
The initial evaluation for open fractures is to rule out any other life-threatening injuries. Advanced Trauma Life Support is the initial protocol to rule out such injuries. Once the patient is stabilised, orthopedic injuries can be evaluated including determining the severity of injury using a classification system. Mechanism of injury is important to know the amount energy that is transferred to the patient and the level of contamination. Every limb should be exposed to evaluate any other hidden injuries. Characteristics of the wound should be noted in detail. Neurology and the vascular status of the affected limb are important to rule out any nerve or blood vessels injuries. High index of suspicion of compartment syndrome should be maintained for leg and forearm fractures.Classification
There are a number of classification systems attempting to categorise open fractures such as Gustilo-Anderson open fracture classification, Tscherne classification, and Müller AO Classification of fractures. However, Gustilo-Anderson open fracture classification is the most commonly used classification system. Gustilo system grades the fracture according to energy of injury, soft tissue damage, level of contamination, and comminution of fractures. The higher the grade, the worse the outcome of the fracture.| Gustilo Open Fracture Classification | |
| Gustilo Grade | Definition |
| I | Open fracture, clean wound, wound <1 cm in length |
| II | Open fracture, wound > 1 cm but < 10 cm in length without extensive soft-tissue damage, flaps, avulsions |
| IIIA | Open fracture with adequate soft tissue coverage of a fractured bone despite extensive soft tissue laceration or flaps, or high-energy trauma regardless of the size of the wound |
| IIIB | Open fracture with extensive soft-tissue loss and periosteal stripping and bone damage. Usually associated with massive contamination. Will often need further soft-tissue coverage procedure |
| IIIC | Open fracture associated with an arterial injury requiring repair, irrespective of degree of soft-tissue injury. |
However, Gustilo system is not without its limitations. The system has limited interobserver reliability at 50% to 60%. The size of injury on the skin surface does not necessarily reflect the extent of deep underlying soft tissue injury. Therefore, the true grading of Gustilo can only be done in operating theatre.
Management
Acute management
Urgent interventions, including therapeutic irrigation and wound debridement, are often necessary to clean the area of injury and minimize the risk of infection. Other risks of delayed intervention include long-term complications, such as deep infection, vascular compromise and complete limb loss. After wound irrigation, dry or wet gauze should be applied to the wound to prevent bacterial contamination. Taking photographs of the wound can help to reduce the need of multiple examinations by different doctors, which could be painful. Limb should be reduced and placed in a well-padded splint for immobilization of fractures. Pulses should be documented before and after reduction.Wound cultures are positive in 22% of pre-debridement cultures and 60% of post-debridement cultures of infected cases. Therefore, pre-operative cultures no longer recommended. The value of post-operative cultures is unknown. Tetanus prophylaxis is routinely given to enhance immune response against Clostridium tetani. Anti-tetanus immunoglobulin is only indicated for those with highly contaminated wounds with uncertain vaccination history. Single intramuscular dose of 3000 to 5000 units of tetanus immunoglobulin is given to provide immediate immunity.
Another important clinical decision during acute management of open fractures involves the effort to avoid preventable amputations, where functional salvage of the limb is clearly desirable. Care must be taken to ensure this decision is not solely based on an injury severity tool score, but rather a decision made following a full discussion of options between doctors and the person, along with their family and care team.
Antibiotics
Administration of broad-spectrum intravenous antibiotics as soon as possible is necessary to reduce the risk of infection. However, antibiotics may not provide necessary benefits in open finger fractures and low velocity firearms injury. First generation cephalosporin is recommended as first line antibiotics for the treatment of open fractures. The antibiotic is useful against gram positive cocci and gram negative rods such as Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae. To extend the coverage of antibiotics against more bacteria in Type III Gustilo fractures, combination of first generation cephalosporin and aminoglycoside or a third generation cephalosporin is recommended to cover against nosocomial gram negative bacilli such as Pseudomonas aeruginosa. Adding penicillin to cover for gas gangrene caused by anaerobic bacteria Clostridium perfringens is a controversial practice. Studies has shown that such practice may not be necessary as the standard antibiotic regimen is enough to cover for Clostridial infections. Antibiotic impregnated devices such as tobramycin impregnated Poly beads and antibiotic bone cement are helpful in reducing rates of infection. The use of absorbable carriers with implant coatings at the time of surgical fixation is also an effective means of delivering local antibiotics.There has been no agreement on the optimal duration of antibiotics. Studies has shown that there is no additional benefits of risk of infection when giving antibiotics for one day, when compared to giving antibiotics for three days or five days. However, at present, there is only low to moderate evidence for this and more research is needed. Some authors recommended that antibiotics to be given for three doses for Gustilo Grade I fractures, for one day after wound closure in Grade II fractures, three days in Grade IIIA fractures, and three days after wound closure for Grade IIIB and IIIC.