Primary: initial blast wave energy dissipated onto the body.
b. Secondary: fragments emitted from the explosive device lodge into the body.
c. Tertiary: resulting injury from victim being projected against ground or solid objects.
II. Classification
A. Gustilo–Anderson classification
1. Originally based on open tibial fractures and the size of associated soft-tissue wound but commonly applied to all open fractures. Classification is made in the operating room at time of the final debridement. Infection rates increase dramatically between lower types and IIIB and IIIC fractures.
a. Type 1—skin laceration < 1 cm in length and low-energy fracture pattern.
b. Type 2—1 to 10 cm wound length without extensive soft tissue damage or high-energy fracture pattern.
c. Type 3A—open wound > 10 cm in length that can be closed primarily or with a skin graft. Smaller wounds are included if extensive stripping of periosteum, heavy contamination, or high-energy fractures (segmental or highly comminuted) are present.
d. Type 3B—extensive soft tissue loss, typically a wound that requires rotational or free tissue transfer for closure when bone is at anatomic length. A fracture would be considered to be classified as a 3B type if shortening of the limb is required to allow for wound closure.
e. Type 3C—arterial vascular injury in the affected extremity that requires vascular repair for limb viability. Repairs to vessels in limbs that have adequate perfusion are not 3C injuries.
B. Orthopaedic Trauma Association open fracture classification
1. Initially it was utilized in research setting to describe soft-tissue injuries in greater detail.
2. Numerical score from 1 (least severe) to 3 (most severe) for each of the following five categories of open fracture assessment: skin injury, muscle injury, arterial injury, degree of contamination, and bone loss.
III. Principles of Open Fracture Management in the Emergent Setting
A. Clinical assessment and initial management
1. Neurovascular evaluation:
a. Vascular compromise is common.
b. Abnormal pulse exam following fracture reduction necessitates further evaluation with ankle brachial indices (ABI) and/or computed tomography angiogram to diagnose vascular injury.
c. Assess for neurologic deficit.
d. Limbs with open fractures can still develop compartment syndrome.
2. Soft tissue assessment:
a. Careful evaluation of all wounds and abrasions in fractured limbs is done for making the diagnosis of an open fracture. Be aware that the wound may be at some distance from the fracture location as the bone may have displaced during the injury.
b. Evaluate degree of contamination, wound size, and potential need for soft tissue reconstruction (rotational flap, free tissue transfer). High level of contamination may warrant more urgent operative debridement.
c. Entrapped tendons may prevent joint or fracture reduction.
d. Completely devitalized bone should be removed, unless it contains articular cartilage.
e. Sterile gauze should be applied to open wound either alone or with antiseptic solution. Consider packing wound with mild compression to control bleeding when clinically warranted.
B. Role of antibiotic treatment
1. There is level 1 evidence to support that antibiotic treatment prior to the operation has a protective effect against early infection compared to no antibiotics or placebo.
2. Antibiotics should be started as soon after injury as possible.
3. Weak evidence to support the best type of antibiotic to be administered, but consensus opinion is an intravenous administration of first-generation cephalosporin for all open fractures. Local differences or protocols may exist at trauma centers.
4. Gentamicin or equivalent is frequently supplemented for more contaminated injuries to give additional coverage against gram-negative bacteria.
a. Aminoglycosides carry an increased risk of nephrotoxicity in trauma patients.
5. Consider adding penicillin G or equivalent for gross contamination (fecal/soil/marine) for additional anaerobic bacterial coverage.
6. Clindamycin is an alternative to cephalosporin treatment in penicillin-allergic patients.
7. Piperacillin/tazobactam are acceptable alternative to cefazolin and gentamicin.
8. No consensus on length of antibiotic treatment warranted for therapeutic benefit. Many centers recommend 24 to 48 hours of treatment after each debridement until definitive soft-tissue closure or coverage.
C. Radiographic evaluation
1. X-rays should be performed primarily to assess the extent of osseous injury and guide the appropriate immobilization needed to stabilize the injury.
2. Consider CT imaging if further bone detail is warranted prior to surgical intervention.
IV. Surgical Management of Open Fractures
A. Goals of debridement
1. Open fractures are contaminated. Consider the level of contamination, severity of the wound, and the health of the patient when determining the risk of infection.
2. Timing of surgical debridement:
a. A recent meta-analysis found no difference between debridements performed before and after 12 hours from time of injury.
b. Data from the LEAP study found no difference in timing of debridement; however, timing of arrival to the definitive treatment center was correlated with infection.
c. It is recommended that open fractures should undergo surgical irrigation and debridement within the first 24 hours after injury when the patient is appropriately resuscitated and medically optimized for surgery, but this time point is based mostly on expert opinion. There may be open fractures where more urgent debridement is necessary such as associated vascular injuries or grossly contaminated wounds.
3. Surgical approach:
a. Removal of all devitalized and contaminated tissue to minimize infection.
b. Excision of bone fragments devoid of soft tissue attachment except when that bone has significant portions of the joint attached to it.
c. There is wide variation among surgeons regarding the extent of osseous debridement necessary. For example, aggressive debridements may reduce the risk of infection, but large bone defects create challenges with initial limb stabilization and may be associated with
