Open fracture
Open fracture is a type of bone fracture in orthopedics, frequently caused by high energy trauma. It is a bone fracture associated with a break in the skin continuity which can cause complications such as infection, malunion, and nonunion. Gustilo open fracture classification is the most commonly used method to classify open fractures, 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. Cephalosporins are generally the first line of antibiotics. The antibiotics are continued for 24 hours to minimize the risk of infections. Therapeutic irrigation, wound debridement, early wound closure and bone fixation are the main management of open fractures. All these actions aimed to reduce the risk of infections.
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
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.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. 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 is important to rule our any nerve or blood vessels injuries. High index of suspicion of compartment syndrome should be maintained for leg and forearm fractures.There are a number of classification system attempting to categorise open fractures such as Gustilo open fracture classification, Tscherne classification, and Müller AO Classification of fractures. However, Gustilo 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 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 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.