Open fracture

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Open fracture
Gustilo type 2 fracture.png
Gustilo Type 2 fracture
Specialty Orthopedics

An open fracture, also called a compound fracture, is a type of bone fracture in orthopedics that is 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.

Contents

Causes

Open fractures can occur due to direct impacts such as high-energy physical forces (trauma), motor vehicular accidents, firearms, and falls from height. [1] Indirect mechanisms include twisting (torsional injuries) and falling from a standing position. [1] 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: [2] [3]

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.[ citation needed ]

Pathological fractures

Result from minor trauma to diseased bone. These preexisting processes include metastatic lesions, bone cysts, advanced osteoporosis, etc. [3]

Fracture-dislocations

Severe injury in which both fracture and dislocation take place simultaneously. [2]

Gunshot wounds

Caused by high-speed projectiles, they cause damage as they go through the tissue, through secondary shock wave and cavitation. [3]

Diagnosis

The initial evaluation for open fractures is to rule out any other life-threatening injuries. Advanced Trauma Life Support (ATLS) 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 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. [4]

There are a number of classification systems 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. [4]

Gustilo open fracture Classification
Gustilo GradeDefinition
IOpen fracture, clean wound, wound <1 cm in length
IIOpen fracture, wound > 1 cm but < 10 cm in length [5] without extensive soft-tissue damage, flaps, avulsions
IIIAOpen fracture with adequate soft tissue coverage of a fractured bone despite extensive soft tissue laceration or flaps, or high-energy trauma (gunshot and farm injuries) regardless of the size of the wound [5] [6]
IIIBOpen fracture with extensive soft-tissue loss and periosteal stripping and bone damage. Usually associated with massive contamination. [5] [6] Will often need further soft-tissue coverage procedure (i.e. free or rotational flap)
IIICOpen 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. [4]

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. [7] Other risks of delayed intervention include long-term complications, such as deep infection, vascular compromise and complete limb loss. [7] 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. [4]

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. [4]

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. [7] 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. [7]

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 (cefazolin) 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 (gentamicin or tobramycin) 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(methyl methacrylate) (PMMA) beads and antibiotic bone cement are helpful in reducing rates of infection. [4] The use of absorbable carriers with implant coatings at the time of surgical fixation is also an effective means of delivering local antibiotics. [8]

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. [4] [9] However, at present, there is only low to moderate evidence for this and more research is needed. [9] 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. [4]

Wound irrigation

There has been no agreement for the optimal solution for wound irrigation. Studies found out that there is no difference in infection rates by using normal saline or other various forms of water (distilled, boiled, or tap). [10] There is also no difference in infection rates when using normal saline with castile soap compared with normal saline together with bacitracin in irrigating wounds. Studies also have shown that there is no difference in infection rates using low pressure pulse lavage (LPPL) when compared to high pressure pulse lavage (HPPL) in irrigating wounds. Optimal amount of fluid for irrigation also has not been established. It is recommended that the amount of irrigation solution to be determined by the severity of the fracture, with 3 litres for type I fractures, 6 litres for type II fractures, and 9 litres for type III fractures. [4]

Wound debridement

The purpose of wound debridement is to remove all contaminated and non-viable tissues including skin, subcutaneous fat, muscles and bones. Viability of bones and soft tissues are determined by their capacity to bleed. Meanwhile, the viability of muscles is determined by colour, contractility, consistency, and their capacity to bleed. The optimal timing of performing wound debridement and closure is debated and dependent on the severity of the injury, resources and antibiotics available, and individual needs. [11] Debridement time can vary from 6 to 72 hours, and closure time can be immediate (less than 72 hours) or delayed (72 hours to up to 3 months). [11] There is no difference in infection rates for performing surgery within 6 hours of injury when compared to until 72 hours after injury. [4] [12]

Surgical management

Early fracture immobilisation and fixation helps to prevent further soft tissue injury and promotes wound and bone healing. This is especially important in the treatment of intraarticular fractures where early fixation allows early joint motion to prevent joint stiffness. Fracture management depends on the person's overall well being, fracture pattern and location, and the extent of soft tissue injury. Both reamed and unreamed intramedullary nailing are accepted surgical treatments for open tibial fracture. [13] Both techniques have similar rates of postoperative healing, postoperative infection, implant failure and compartment syndrome. [13] Unreamed intramedullary nailing is advantageous because it has a lower incidence of superficial infection and malunion compared to external fixation. [14]  However, unreamed intramedullary nailing can result in high rates of hardware failure if a person's weight bearing after surgery is not closely controlled. [14]  Compared to external fixation, unreamed intramedullary nailing has similar rates of deep infection, delayed union and nonunion following surgery. [14] For open tibial fractures in children, there is an increasing trend of using orthopedic cast rather than external fixation. Bone grafting is also helpful in fracture repair. However, internal fixation using plates and screws is not recommended as it increase the rate of infection. [4] Amputation is a last resort intervention, and is determined by factors such as tissue viability and coverage, infection, and the extent of damage to the vascular system. [15]

Wound management

Early wound closure is recommended to reduce the rates hospital-acquired infection. For Grade I and II fractures, wound can be healed by secondary intention or through primary closure. There is conflicting evident to suggest the effectiveness of Negative-pressure wound therapy (vacuum dressing), with several sources citing a decreased risk in infection, [15] [16] and others suggesting no proven benefit. [17]

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. [4] 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. [18]

History

Before the 1850s, surgeons usually amputated the limbs for those with open fractures, as it was associated with severe sepsis and gangrene which can be life threatening. It was only until the 20th century, when Joseph Lister adopted the aseptic technique in surgeries, that the rate of death from open fractures reduced from 50% to 9%. [4]

Related Research Articles

Bone healing Healing from bone injury

Bone healing, or fracture healing, is a proliferative physiological process in which the body facilitates the repair of a bone fracture.

Tenosynovitis

Tenosynovitis is the inflammation of the fluid-filled sheath that surrounds a tendon, typically leading to joint pain, swelling, and stiffness. Tenosynovitis can be either infectious or noninfectious. Common clinical manifestations of noninfectious tenosynovitis include de Quervain tendinopathy and stenosing tenosynovitis

Bone fracture Physical damage to the continuity of the bone

A bone fracture is a medical condition in which there is a partial or complete break in the continuity of the bone. In more severe cases, the bone may be broken into several pieces. A bone fracture may be the result of high force impact or stress, or a minimal trauma injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, osteopenia, bone cancer, or osteogenesis imperfecta, where the fracture is then properly termed a pathologic fracture.

Clavicle fracture

A clavicle fracture, also known as a broken collarbone, is a bone fracture of the clavicle. Symptoms typically include pain at the site of the break and a decreased ability to move the affected arm. Complications can include a collection of air in the pleural space surrounding the lung (pneumothorax), injury to the nerves or blood vessels in the area, and an unpleasant appearance.

External fixation

External fixation is a surgical treatment wherein rods are screwed into bone and exit the body to be attached to a stabilizing structure on the outside of the body. It is an alternative to internal fixation, where the components used to provide stability are positioned entirely within the patient's body. It is used to stabilize bone and soft tissues at a distance from the operative or injury focus. They provide unobstructed access to the relevant skeletal and soft tissue structures for their initial assessment and also for secondary interventions needed to restore bony continuity and a functional soft tissue cover.

Nonunion Failure of a bone to heal after breakage

Nonunion is permanent failure of healing following a broken bone unless intervention is performed. A fracture with nonunion generally forms a structural resemblance to a fibrous joint, and is therefore often called a "false joint" or pseudoarthrosis. The diagnosis is generally made when there is no healing between two sets of medical imaging, such as X-ray or CT scan. This is generally after 6–8 months.

Knee replacement

Knee replacement, also known as knee arthroplasty, is a surgical procedure to replace the weight-bearing surfaces of the knee joint to relieve pain and disability. It is most commonly performed for osteoarthritis, and also for other knee diseases such as rheumatoid arthritis and psoriatic arthritis. In patients with severe deformity from advanced rheumatoid arthritis, trauma, or long-standing osteoarthritis, the surgery may be more complicated and carry higher risk. Osteoporosis does not typically cause knee pain, deformity, or inflammation and is not a reason to perform knee replacement

Distraction osteogenesis

Distraction osteogenesis (DO), also called callus distraction, callotasis and osteodistraction, is a process used in orthopedic surgery, podiatric surgery, and oral and maxillofacial surgery to repair skeletal deformities and in reconstructive surgery. The procedure involves cutting and slowly separating bone, allowing the bone healing process to fill in the gap.

Ollier disease

Ollier disease is a rare sporadic nonhereditary skeletal disorder in which typically benign cartilaginous tumors (enchondromas) develop near the growth plate cartilage. This is caused by cartilage rests that grow and reside within the metaphysis or diaphysis and eventually mineralize over time to form multiple enchondromas. Key signs of the disorder include asymmetry and shortening of the limb as well as an increased thickness of the bone margin. These symptoms are typically first visible during early childhood with the mean age of diagnosis being 13 years of age. Many patients with Ollier disease are prone to develop other malignancies including bone sarcomas that necessitate treatment and the removal of malignant bone neoplasm. Cases in patients with Ollier disease has shown a link to IDH1, IDH2, and PTH1R gene mutations. Currently, there are no forms of treatment for the underlying condition of Ollier disease but complications such as fractures, deformities, malignancies that arise from it can be treated through surgical procedures. The prevalence of this condition is estimated at around 1 in 100,000. It is unclear whether the men or women are more affected by this disorder due to conflicting case studies.

Calcaneal fracture

A calcaneal fracture is a break of the calcaneus. Symptoms may include pain, bruising, trouble walking, and deformity of the heel. It may be associated with breaks of the hip or back.

Gunshot wound Form of physical trauma sustained from the Discharge of arms or munitions

A gunshot wound (GSW) is physical trauma caused by a bullet from a firearm. Damage may include bleeding, broken bones, organ damage, infection of the wound, or loss of the ability to move part of the body. Damage depends on the part of the body hit, the path the bullet follows through the body, and the type and speed of the bullet. Long-term complications can include lead poisoning and post-traumatic stress disorder (PTSD).

Taylor Spatial Frame

The Taylor Spatial Frame (TSF) is an external fixator used by podiatric and orthopaedic surgeons to treat complex fractures and bone deformities. The medical device shares a number of components and features of the Ilizarov apparatus. The Taylor Spatial Frame is a hexapod device based on a Stewart platform, and was invented by orthopaedic surgeon Charles Taylor. The device consists of two or more aluminum or carbon fibre rings connected by six struts. Each strut can be independently lengthened or shortened to achieve the desired result, e.g. compression at the fracture site, lengthening, etc. Connected to a bone by tensioned wires or half pins, the attached bone can be manipulated in three dimensions and 9 degrees of freedom. Angular, translational, rotational, and length deformities can all be corrected simultaneously with the TSF.

Intramedullary rod

An intramedullary rod, also known as an intramedullary nail or inter-locking nail or Küntscher nail, is a metal rod forced into the medullary cavity of a bone. IM nails have long been used to treat fractures of long bones of the body. Gerhard Küntscher is credited with the first use of this device in 1939, during World War II, for soldiers with fractures of the femur. Prior to that, treatment of such fractures was limited to traction or plaster, both of which required long periods of inactivity. IM nails resulted in earlier return to activity for the soldiers, sometimes even within a span of a few weeks, since they share the load with the bone, rather than entirely supporting the bone.

The Gustilo open fracture classification system is the most commonly used classification system for open fractures. It was created by Ramón Gustilo and Anderson, and then further expanded by Gustilo, Mendoza, and Williams.

Femoral fracture

A femoral fracture is a bone fracture that involves the femur. They are typically sustained in high-impact trauma, such as car crashes, due to the large amount of force needed to break the bone. Fractures of the diaphysis, or middle of the femur, are managed differently from those at the head, neck, and trochanter

Pilon fracture

A pilon fracture, is a fracture of the distal part of the tibia, involving its articular surface at the ankle joint. Pilon fractures are caused by rotational or axial forces, mostly as a result of falls from a height or motor vehicle accidents. Pilon fractures are rare, comprising 3 to 10 percent of all fractures of the tibia and 1 percent of all lower extremity fractures, but they involve a large part of the weight-bearing surface of the tibia in the ankle joint. Because of this, they may be difficult to fixate and are historically associated with high rates of complications and poor outcome.

The following outline is provided as an overview of and topical guide to trauma and orthopaedics:

Early appropriate care (EAC) is a system in orthopaedic trauma surgery aiming to identify serious major trauma patients and treat the most time-critical injuries without adding to their physiological burden.

Tibia shaft fracture

Tibia shaft fracture is a fracture of the proximal (upper) third of the tibia. Due to the location of the tibia, it is frequently injured. Thus it is the most commonly fractured long bone in the body.

Bone malrotation refers to the situation that results when a bone heals out of rotational alignment from another bone, or part of bone. It often occurs as the result of a surgical complication after a fracture where intramedullary nailing (IMN) occurs, especially in the femur and tibial bones, but can also occur genetically at birth. The severity of this complication is often neglected due to its complexity to detect and treat, yet if left untreated, bone malrotation can significantly impact regular bodily functioning, and even lead to severe arthritis. Detection throughout history has become more advanced and accurate, ranging from clinical assessment to ultrasounds to CT scans. Treatment can include an osteotomy, a major surgical procedure where bones are cut and realigned correctly, or compensatory methods, where individuals learn to externally or internally rotate their limb to compensate for the rotation. Further research is currently being examined in this area to reduce occurrences of malrotation, including detailed computer navigation to improve visual accuracy during surgery.

References

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