Introduction

Open fractures are a unique subset of fractures because of the exposure of bone to contamination from the environment and the disruption of soft-tissue integrity, which increases the risk for infection, delayed union, and even amputation. Infection is considered to be the major cause of both nonunion and poor function after such injuries, and therefore the aim of primary treatment is to create the ideal biological environment for the prevention of infection.

Initial Stabilisation

Open fractures are usually the result of high-energy trauma. This should alert the clinician to the possibility of associated injuries, making detailed evaluation and appropriate resuscitation of the patient a necessity.

Classification of the Injury

Open fracture classification schemes describe the relationship and degree of soft-tissue damage and are designed to correlate with treatment guidelines and prognosis. The most common classification method is the Gustilo-Anderson classification scheme.¹

 Type 1: An open fracture with a wound smaller than 1 cm. Surrounding soft tissues are mildly/moderately contused. Frequently the external wound is created from the inside out.

 Type 2: An open fracture with a wound larger than 1 cm without extensive soft-tissue damage, flaps, or avulsions. The external wound typically is created from the outside in.

 Type 3: An open fracture with extensive soft-tissue damage. Soft-tissue avulsion, de-gloving injury, and bone loss are frequently noted. These include fractures with accompanying neurovascular injury requiring repair, gunshot injuries, and traumatic partial amputations.

Systemic Antibiotic Therapy

Antibiotic use has long been considered the standard of care. Benefit was confirmed by a Cochrane review demonstrating that antibiotic administration after an open fracture reduced infection rates by 59%.² The importance of prompt initiation of intravenous antibiotics has also been documented. A significant decrease in infection rate has been noted when antibiotics are administered within three hours of injury when compared to four hours or longer.³

Although in the past, cultures were routinely performed before and after debridement of open fractures, their utility has been questioned. The organisms that are found contaminating an open fracture on presentation do not represent those that will eventually cause infection, and most authors no longer recommend these to guide antibiotic choice.

Systemic antibiotics selected for initial treatment should be directed toward a wide range of gram-positive and gram-negative organisms. The degree of soft tissue compromise and increased contamination in type 3 fractures puts them at an increased risk for infection, and they require broader antimicrobial coverage.⁴ Initial use of a first- or second-generation cephalosporin for type 1 and 2 fractures and the combination of a cephalosporin and a fluoroquinolone for type 3 fractures are recommended.⁴

Irrigation

Preventing further contamination and soft tissue trauma is of the utmost importance. A temporary sterile covering should be applied until debridement and irrigation can be performed. Copious amounts of sterile, water-soluble lubrication should be placed into the wound and the hair clipped widely. Bordering skin is aseptically cleansed with a 4% chlorhexidine solution.

Irrigation is a key component of the effort to prevent infection, as it decreases bacterial load and removes foreign bodies. There has been significant debate regarding the optimal pressure for irrigation and whether sterile saline alone should be used or whether additives such as antiseptics, antibiotics, or soaps are appropriate.

Recommendations vary, but a recent review⁵ made the following recommendations:

 Normal saline should be used routinely for fracture irrigation.

 Antibiotics and antiseptics as additives should be limited because of inconclusive evidence and potential risks.

 Low-pressure irrigation methods should be used routinely.

 Surgeons who continue to use high-pressure pulsed lavage systems should limit the pressure to 50 lb psi.

Debridement

Emergency operative treatment has long been the standard of care for open fractures with a "six-hour window" often being mentioned. The origin of this window, however, is unclear. Many studies have called the "six-hour window" into question, having found either no significant difference in infection rates between fractures operated before or after six hours or no correlation between time to first debridement and likelihood of infection.

In the prevention of infection, the time from injury to debridement is probably less important than other factors, such as adequacy of debridement and timeliness of soft-tissue coverage. Treatment decisions and prognosis should be based on assessment of soft-tissue damage, viability, contamination, and infection - not on a time interval.

Wound Management

Once the wound has been irrigated, cleaned, and thoroughly debrided, early aggressive treatment with rigid bone fixation and soft tissue reconstruction is widely accepted as the treatment of choice.

Historically, the closure of open fracture wounds has been delayed to prevent infection with contaminating organisms. While this strategy remains the generally accepted approach in settings characterized by substantial contamination, many orthopaedic surgeons have begun to consider earlier closure of open fracture wounds that have been adequately debrided. Based on the human literature, early closure of thoroughly debrided wounds is safe and may improve outcomes.

However, assessing the adequacy of debridement can be difficult, and, if there is any doubt as to whether there has been adequate debridement, the wound should not be closed, as this can lead to future complications. There are multiple options for wound treatment prior to closure, including the placement of antibiotic beads and negative pressure wound therapy. Once the bone is covered by healthy tissue, local skin, transposition flaps, axial pattern flaps, or free skin grafts can be used for definitive closure.

Fracture Stabilisation

Controversy regarding the most appropriate method of fixation is vast. A number of stabilisation methods are available, and success has been reported with both internal and external fixation methods. In any given situation, the best option for fixation depends on a number of factors including the bone involved, the fracture site and type, the wound location, the skin vascularity, and the condition of the patient. Ideally, a surgical approach away from the initial wound is selected.

Conventionally, the use of metallic implants to stabilise open fractures was avoided because of the supposedly higher infection risk. However, ongoing instability at the fracture site constitutes a higher infection risk than ensuring stability with a sterile implant.^6-8 Stability is beneficial to revascularization, leads to increased tissue microperfusion, reduces dead space, and decreases hematoma formation. Conversely, instability at a fracture site may provide conditions favouring bacterial proliferation, namely local necrosis of surrounding soft tissues and exudate formation. Metal does not stimulate or promote wound sepsis, and the benefits of fracture stability override any potential harmful effects of implants.

It is a common misconception that open fractures preclude the use of internal fixation and necessitate the use of external skeletal fixation. All forms of internal fixation remain options in most fractures including interlocking nails and plates and screws. The severity of the soft-tissue injury rather than the choice of implant appears to be the main factor influencing infection and bone healing.

Bone plates have been used to treat type 1 through 3 open fractures with satisfactory final results. If internal fixation is elected, owners should be warned that the implants may require removal in the future. External fixation at a distance from the open fracture has been a popular choice previously, but external fixators are cumbersome and have several disadvantages. They limit access to the wound and pin track sepsis is common. The results of a retrospective study on plate fixation of open fractures in people concluded that the traditional fear of plating a grade 1 or 2 open fracture was unjustified.⁹ However, plate fixation is not appropriate for all open fractures, and it is recommended that this still be avoided in grade 3 open fractures since the incidence of infection is high.⁹ External fixation is an alternative method of stabilisation in these severe injuries, but whichever the chosen method, adequate wound debridement and early skin cover are essential to reduce septic complications.

Generally type 1 open fractures can be treated using the same method of fixation as would be used for a closed fracture of similar configuration. Type 2 fractures that are properly managed often can be treated using the same method of fixation as would be used for closed fractures, but appropriate, experienced judgement is necessary. Extensive soft-tissue damage associated with type 3 open fractures may preclude internal fixation.

Complications and Followup

Postoperatively, frequent and regular checks are necessary to assess the wound and limb function. Radiographic evaluation may be required more frequently than for a closed fracture to monitor for signs of a deep-seated infection.

Potential complications include infection, delayed union or nonunion, and soft-tissue necrosis with breakdown of soft-tissue repair. Amputation may be necessary with type 3 fractures, fractures with multiple complications, and those associated with severe neurovascular injury. Septicemia and death may result from infections that are not treated appropriately.

References

1.  Gustilo RB, Anderson JT. Prevention of infection in the treatment of one thousand and twenty-five open fractures of long bones: retrospective and prospective analyses. J Bone Joint Surg Am. 1976;58:453–458.

2.  Gosselin RA, Roberts I, Gillespie WJ. Antibiotics for preventing infection in open limb fractures. Cochrane Database Syst Rev. 1 2004:CD003764.

3.  Patzakis MJ, Wilkins J. Factors influencing infection rate in open fracture wounds. Clin Orthop Relat Res. 1989;243:36.

4.  Patzakis MJ, Bains RS, Lee J, et al. Prospective, randomized, double-blind study comparing single-agent antibiotic therapy, ciprofloxacin, to combination antibiotic therapy in open fracture wounds. J Orthop Trauma. 2000;14:529.

5.  Crowley DJ, Kanakaris NK, Giannoudis PV. Irrigation of the wounds in open fractures. J Bone Joint Surg Br. 2007;89B:580–585.

6.  McLaughlin HL. Internal fixation of fractures. Surgery. 1956;39:892.

7.  Muller ME, Allgower M, Schneider R, Willenegger H, eds. Manual of Internal Fixation. 2nd ed. Berlin, Heidelberg, New York: Springer-Verlag; 1979.

8.  Allgower M, Border JR. Management of fractures in the multiple trauma patient. World J Surg. 1983;7:88.

9.  Clifford RP, Beuchamp CG, Kellam JF, et al. Plate fixation of open fractures of the tibia. J Bone Joint Surg. 1988;70B:644–648.