Key Insights On Managing Open Ankle Fractures

Open ankle fractures account for approximately 1.5 percent of all ankle fractures and they are associated with soft tissue damage, an increased risk of infection, and possible vascular compromise.¹ The management of these fractures has drastically improved over the past century, leading to a decrease in amputations as well as mortality. This is due to the advancements in antimicrobial therapy as well as improved surgical techniques. Although outcomes have improved, there is still debate regarding multiple aspects in the overall care of these complex and challenging ankle fractures.

Several classification systems have emerged in an effort to grade these injuries. In 1976, Gustilo and Anderson described the most widely used classification system, which Gustilo and colleagues later modified in 1984.^2,3 The system is based on the laceration length, extent of soft tissue damage and the amount of comminution and contamination.

Several studies have examined factors that predict the development of infection, including pre- and post-injury variables. A study by Bowen and coworkers examined 14 immune system compromising factors, including tobacco use, diabetes and malnutrition.⁴ The authors found that patients with one or more compromising factors have a markedly increased risk of infection. The most influential factor affecting the incidence of infection after an open fracture is the severity of the local soft tissue injury, which correlates with the Gustilo and Anderson classification system. In a study by Patzakis and Wilkins, infection rates progressively increased from 1.4 percent for group I injuries to 3.6 percent for group II injuries to 22.7 percent for group III injuries.⁵

Although open fractures have been classically associated with high-energy trauma, it is our experience that open ankle fractures are becoming more common with low-energy injuries, such as a fall or a twist, particularly in patients with diabetic neuropathy. Following initial evaluation and resuscitation according to Advanced Trauma Life Support protocols, the surgeon should aim to prevent infection, promote fracture healing and restore function.⁶

What The Literature Reveals About Antibiotic Management
Consider all open fractures contaminated given that there is communication of the bone with the outside environment. This contamination, along with the presence of devitalized tissue and possible foreign materials, promotes infection.

In 1974, Patzakis and colleagues showed a statistically significant increase in infection rate with open fractures when the patient received no antibiotic versus when the patient received a first-generation cephalosporin.⁷ In 2004, a Cochrane Review confirmed the benefits of antibiotics following open fractures by reporting a 59 percent reduction in the risk of developing an infection.⁸

We now consider intravenous antibiotics to be the standard of care for open fractures and one should start patients on them as soon as possible. Although no definitive algorithm exists for which antibiotics to use for which classification group, it is our recommendation to use a first-generation cephalosporin (or ciprofloxacin in patients with documented penicillin allergies) for group I and II fractures, and add an aminoglycoside for those with group III fracture types. Also add penicillin when conditions favor the development of an anaerobic infection (soil contamination, farm injury, vascular damage).

The duration of these therapies is also an area of debate. Dellinger and colleagues showed that a five-day course of antibiotics had no greater benefit than a one-day course in the prevention of fracture site infection.⁹ Most authors recommend a maximum of three days of antibiotic therapy with repeat three-day courses at the time of subsequent surgical procedures.¹⁰ One should avoid prolonged antibiotic therapy past three days as it may promote the development of resistance as well as other systemic toxicities.

Is There A ‘Golden Period’ For Surgical Intervention With Open Fractures?
Most surgeons learn in their academic and surgical training that they should surgically manage open fractures within six hours in accordance with the “golden period.”

The origin of this period, however, is unclear. In 1973, Robson and coworkers reported that 10⁵ organisms per gram of tissue was the open fracture infection threshold, which patients reached in an average of 5.17 hours.¹¹ A number of studies have shown no significant infection rate in those treated surgically within six hours and those treated at seven hours or later.^12,13

Due to conflicting reports in the literature, it is impossible to argue for or against the “golden period.” In the prevention of infection following open ankle fractures, the time from injury to surgical debridement is likely less crucial than antibiotic administration, adequate debridement and soft tissue coverage.

Managing Wounds To Prevent Post-Op Infection
Many have considered irrigation and debridement of the wound as key to preventing infection following open fractures. The goals are removing necrotic tissue and debris from the wound bed as well as decreasing the bacterial load.

Researchers have discussed the amount of irrigation and specific additives. Anglen proposed a protocol utilizing 3 L for grade I injuries, 6 L for grade II injuries and 9 L for grade III injuries.¹⁴ Although there is no outcome data to support these recommendations, it is the protocol we follow for open fractures of the foot and ankle at our institution. While authors have advocated a variety of irrigation additives, the scientific literature shows no conclusive evidence of their efficacy.

A recent prospective randomized controlled study showed no significant difference with respect to infection and bone healing when comparing non-sterile castile soap with bacitracin solution for the irrigation of 398 lower extremity open fractures.¹⁵ Following irrigation, perform a thorough surgical debridement to remove any nonviable tissue and bone. Loose bone fragments are avascular and one should remove them during the debridement. However, preserve large intra-articular fragments for use in possible reconstruction.

Lee addressed the value of bacterial wound cultures in open fractures in 1997.¹⁶ Only 8 percent of organisms grown on pre-debridement cultures caused an infection and 7 percent of cases with negative pre-debridement cultures went on to become infected. He also found post-debridement cultures to have a greater prognostic value than pre-debridement cultures although it was less than 50 percent.

We recommend obtaining a post-debridement culture to possibly aid in subsequent infection management as well as for medicolegal purposes. After completing irrigation and debridement, one should partially close the wound with the use of retention sutures and a drain to reduce the risk of clostridial myonecrosis. Patients may receive repeat debridement after one to two days based on intraoperative findings, the viability of the soft tissue and the surgeon’s discretion.

How To Stabilize Open Ankle Fractures
Adequate stabilization across the ankle joint protects the soft tissue from further injury, improves healing and promotes early patient mobilization. A number of methods are available for stabilization including cast immobilization, plates and screws, and external fixators.

A temporary delta frame (DePuy Synthes) is beneficial for open ankle fracture management because it keeps the Schanz screws away from the damaged soft tissue, the calcaneal Steinmann pin can aid in fracture reduction and the delta frame allows for access to the wound while maintaining stability. After a thorough irrigation and surgical debridement, apply a delta frame with the primary goal being skeletal stability and not perfect anatomic reduction. The decision on when to perform a definitive open reduction and internal fixation is based on the soft tissue envelope, the absence of soft tissue and bone infection, and surgeon preference.

As we previously stated, we are seeing an increase in open ankle fractures associated with low-energy trauma in patients with diabetic neuropathy. With this in mind, one may need to employ supplemental internal fixation techniques, such as a fibular cage or multiple syndesmotic screws to prevent non-unions and malunions. Also be aware of the potential development of ankle Charcot neuroarthropathy as this can lead to potential postoperative complications with hardware failure or infection.

A Closer Look At A Fracture Management Algorithm
Management of open fractures of the foot and ankle can become complicated, particularly in the presence of polytrauma. An algorithm provides a logical, stepwise reproducible approach that can ultimately decrease complications and optimize outcomes. Surgeons should only initiate this algorithm after completing the primary and secondary surveys according to the Advanced Trauma Life Support protocol.⁶

1. Emergency room management
-Initiation of antibiotic therapy
-Tetanus prophylaxis
-Neurovascular assessment
-Radiographic analysis
-Fracture reduction with splint immobilization
-Surgical planning based on radiographic findings

2. Surgical management
-Classification of injury using the Gustilo and Anderson system intraoperatively
-Thorough and aggressive irrigation and debridement
-Post-debridement deep wound cultures
-Temporary fracture stabilization with external fixator
-Continued local wound care or repeat debridement until wound is clean and soft tissue swelling is minimal

3. Definitive fixation
-Removal of temporary external fixator
-Anatomic reduction with internal fixation (with or without grafting)
-Supplemental fixation in patients with osteoporotic or neuropathic bone
-Continued local wound care
-Rehabilitation

In Summary
Open ankle fractures require urgent attention from the foot and ankle surgeon. Combining antibiotic therapy with a thorough irrigation and debridement is now considered the standard of care. These fractures require immediate stabilization, preferably with an external fixator, to prevent further soft tissue and vascular damage. Perform a definitive open reduction and internal fixation when residual infection has cleared and the soft tissue envelope is adequate, tailoring it to the patient and the nature of the fracture.

Dr. Patel is a third-year foot and ankle surgical resident at Beaumont Hospital-Wayne in Wayne, Mich.

Dr. Fallat is the Program Director of the foot and ankle surgical residency at Beaumont Hospital-Wayne in Wayne, Mich. He is a Fellow of the American College of Foot and Ankle Surgeons.

References

1. Bugler KE, Clement ND, Duckworth AD, et al. Open ankle fractures: who gets them and why? Arch Orthop Trauma Surg. 2015; 135(3):297-303.
2. 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(4):453-458.
3. Gustilo RB, Mendoza RM, William DN. Problems in the management of type III (severe) open fractures: a new classification of type III open fractures. J Trauma Acute Care Surg. 1984; 24(8):742-746.
4. Bowen TR, Widmaier JC. Host classification predicts infection after open fracture. Clin Orthop Rel Res. 2005; 433:205-211.
5. Patzakis MJ, Wilkins J. Factors influencing infection rate in open fracture wounds. Clin Orthop Rel Res. 1989; 243:36-40.
6. Jayaraman S, Sethi D, Wong R. Advanced training in trauma life support for ambulance crews. Cochrane Database Syst Rev. 2014; CD003109.pub3
7. Patzakis MJ, Harvey JP, Ivler D. The role of antibiotics in the management of open fractures. J Bone Joint Surg Am. 1974; 56(3):532-541.
8. Gosselin RA, Roberts I, Gillespie WJ. Antibiotics for preventing infection in open limb fractures. Cochrane Database Syst Rev. 2004;(1):CD003764.
9. Dellinger EP, Caplan ES, et al. Duration of preventative antibiotics administration for open extremity fractures. Arch Surg. 1988; 123(3):333-339.
10. Zalavras CG, Patzakis MJ, Holtom PD, Sherman R. Management of open fractures. Infect Dis Clin North Am. 2005; 19(4):915-929.
11. Robson MC, Duke WF, Krizek TJ. Rapid bacterial screening in the treatment of open wounds. J Surg Res. 1973; 14(5):426-430.
12. Spencer J, Smith A, Woods D. The effect of time delay on infection in open long-bone fractures: a 5-year prospective audit from a district general hospital. Ann Royal Coll Surg Engl. 2004; 86(2):108
13. Bednar DA, Parikh J. Effect of time delay from injury to primary management on the incidence of deep infection after open fractures of the lower extremities caused by blunt trauma in adults. J Orthop Trauma. 1993; 7(6):532-535.
14. Anglen JO. Wound irrigation in musculoskeletal injury. J Am Acad Orthop Surg. 2001; 9(4):219-226.
15. Anglen JO. Comparison of soap and antibiotic solutions for irrigation of lower-limb open fracture wounds. A prospective, randomized study. J Bone Joint Surg Am. 2005; 87(7):1415-1422.
16. Lee J. Efficacy of cultures in the management of open fractures. Clin Orthop Rel Res. 1997; 339:71-75.