Classification of Open Fractures

BASIC SKILLS

Classification and management of acute wounds and open fractures

Systematic approach to traumatic wound management C

History: B Location and size of wound? B Associated tissue loss? B Type or velocity of weapon? B Mechanism? B Energy involved? B Associated thermal or chemical injury? B Degree of contamination? B Need for involvement of multidisciplinary teams?

C

Examination: B Associated injuries B Neurovascular involvement B Bone or joint involvement B Visceral involvement

C

Interventions: B RESUSCITATION B Prophylaxis: tetanus, antibiotics B Photograph wound and then cover with dressing B Analgesia/anaesthesia B Exploration/debridement/washout B Haemostasis B Skeletal stabilization B Revascularization? B Fasciotomies?

C

Definitive management: B Multidisciplinary approach B Closure: when, where and how?

C

Rehabilitation: B Dressings B Splints? B Physiotherapy/hand therapy

Livio Di Mascio

Abstract Acute traumatic wounds and open fractures potentially cause significant morbidity and loss of function. Much of the management of these types of injuries has been developed from the experience of military surgeons during times of armed conflict. The approach to management should start on initial assessment using trauma resuscitation protocols. Once life-threatening injuries have been managed, the wound should be thoroughly debrided and the skeleton stabilized. The wound must be reinspected after 48 hours to evaluate whether further debridement is necessary and plans for soft tissue coverage can be made. The approach to management of open fractures should be systematic, involving both orthopaedic surgeons and plastic surgeons from the outset.

Keywords Acute wounds; open fracture classification; open fracture management; traumatic wounds; wound classification; wound management

The aetiology of traumatic wounds is diverse and the mechanism, pattern, location, energy imparted to the tissues and degree of contamination all play a role in their inherent ability to heal. As such, initial assessment and treatment should be systematic, and subsequent management is tailored to each individual wound. The general principles of wound management are outlined in Box 1.

Types of wound To gain a broad overview of wounds in a clinical context, the terms simple and complex can be used:

Box 1

Simple wounds: involve skin and soft tissues without damage to underlying bone or joint or neurovascular structures. They are not heavily contaminated and do not have significant skin or soft tissue loss.

The ASEPSIS scoring system1 assigns a number of scores to various wound characteristics evaluated during serial assessment over a 5-day period. (Additional treatment, Serous discharge, Erythema, Purulent discharge, separation of deep Tissues, Isolation of bacteria, duration of hospital Stay.) If the summated score is greater than 20, this would suggest that wound infection is present. The National Nosocomial Infection Surveillance System Score2 assigns one point for each of the following criteria:  A non-clean wound (clean-contaminated, contaminated or dirty wound).  American Society of Anaesthesiology score of 3 or more.  An operative time more than the 75th centile for similar procedures. The higher the score, the greater the probability there is wound infection. This is primarily a tool for audit but it does highlight the fact that not only wound characteristics, but also pre-existing patient factors, will influence wound healing.

Complex wounds: involve significant loss of skin or soft tissue. The injury may also involve vital structures, bone or joints or communicate with a hollow viscus. There may also be associated neurovascular injury or a compartment syndrome. These types of wounds often are heavily contaminated.

Wound classification The use of scoring systems can be helpful as an audit and research tool and to predict possible complications. There are two scoring systems that are relevant to the acute traumatic wound:

Livio Di Mascio MBBS FRCS(Tr & Orth) is a Specialist Registrar in Trauma and Orthopaedic Surgery at the Royal National Orthopaedic Hospital, Stanmore, UK. Conflicts of interest: none declared.

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Open fractures

by the British Orthopaedic Association and British Association of Plastic, Reconstructive and Aesthetic Surgeons in 2009.5 Traditional teaching has been that the timing of definitive debridement should be within 6 hours of the injury. Karl Reyher, in 1881, reported a decrease in mortality rates with the use of early debridement during the Franco-Prussian War. Later in 1898, Freidrich demonstrated in a guinea pig model that the effectiveness of debridement of a soft tissue wound was limited to about 6 hours. This has never been reproduced although it has been demonstrated that starting broad-spectrum antibiotics within 3 hours of injury will reduce infection rates by almost 40%.6 The new guidelines have recognized that the best outcomes are achieved by timely, specialist surgery rather than emergency surgery by less experienced teams. It should be noted that the guidelines are specifically for high-energy lower limb fractures where a significant soft tissue defect, vascular injury or contamination exists. The guidelines also are, however, a very useful tool in guiding treatment in all open fractures.

The presence of a soft tissue wound communicating with an underlying fracture remains a true orthopaedic emergency. The skin acts as a barrier preventing the invasion of microorganisms which would otherwise colonize and infect the fracture site. Infection complicating a fracture may well lead to non-union with subsequent deformity and loss of function and may culminate in chronic deep bone infection which is difficult to eradicate. Current preference in terminology is to describe such fractures as ‘open fractures’ rather than compound injuries. The Gustilo and Anderson3 classification (Box 2) is the most commonly used to describe open fractures. It takes into account a number of factors, not just the size of the associated wound. The presence or absence of a neurovascular injury, the degree of contamination (farmyard injuries are grade III injuries), energy transfer (degree of fragmentation and periosteal stripping) and wound dimensions are used to classify the injury. It has been shown that the grade correlates with the risk of infection.4 The definitive grade should be assigned in theatre after thorough debridement.

Use of antibiotics The use of antibiotics in traumatic wounds that do not involve bone or joint remains controversial. However, antibiotics should be administered as soon as possible in all open fractures, and preferably within 3 hours.6 Organisms that require coverage include: Staphylococcus species, Pseudomonas species, Enterococcus, Escherichia coli, Proteus species, Enterobacter, Klebsiella and Serratia species. The current guidelines recommend the use of co-amoxyclav (1.2 g) or cefuroxime (1.5 g) 8-hourly and are continued until wound debridement. Clindamycin 600 mg 6-hourly can be used if penicillin allergy exists. At the time of first debridement, co-amoxyclav (1.2 g) or cefuroxime (1.5 g) should be given along with gentamicin (1.5 mg/kg) at induction of anaesthesia. This should be continued until soft tissue cover is achieved or for a maximum of 72 hours, whichever is sooner. Gentamicin (1.5 mg/kg) and either vancomycin (1 g) or teicoplanin (800 mg) should be administered at induction of anaesthesia at the time of definitive skeletal stabilization and definitive soft tissue closure. Vancomycin should ideally be given 90 minutes prior to surgery and these agents should not be continued postoperatively.5

Management of traumatic wounds and open fractures Early administration of systemic antibiotics and timely surgical debridement, skeletal stabilization and delayed wound closure are the mainstay principles of treatment in open fractures. Initial guidelines for the management of open fractures were published in 1997. This guidance has subsequently been revised

GustiloeAnderson open fracture classification3 Grade I: The wound is less than 1 cm long. It is usually a moderately clean puncture, through which a spike of bone has pierced the skin. There is little soft-tissue damage and no sign of crushing injury. The fracture is usually simple, transverse, or short oblique, with little fragmentation. Grade II: The laceration is more than 1 cm long, and there is no extensive soft-tissue damage, flap, or avulsion. There is slight or moderate crushing injury, moderate fragmentation of the fracture, and moderate contamination.

Tetanus prophylaxis Grade III: These are characterized by extensive damage to soft tissues, including muscles, skin, and neurovascular structures, and a high degree of contamination. The fracture is often caused by high-velocity trauma, resulting in a great deal of fragmentation and instability. C III A e Soft tissue coverage of the fractured bone is adequate. C III B e Extensive injury to, or loss of soft tissue, with periosteal stripping and exposure of bone, massive contamination, and severe fragmentation of the fracture. After debridement and irrigation a local or free flap is needed for coverage. C III C e Any open fracture that is associated with an arterial injury that must be repaired, regardless of the degree of soft tissue injury.

The introduction of a comprehensive infant vaccination programmes in the 1960s has dramatically reduced the incidence of tetanus in the UK although there are still approximately 10 cases per year.7 Tetanus contamination is more likely in wounds that are contaminated with soil or manure, and deep wounds that contain devitalized tissue, especially muscle. Current guidelines are illustrated in Table 1.

Timing of surgery Unless heavily contaminated by marine, agricultural or sewage material the initial debridement should take place by a senior orthopaedic and plastic surgeon on a dedicated routine trauma operating list. Some patients who are multiply injured and have open fractures may also require urgent surgery. Where possible,

Box 2

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Guidelines for tetanus prophylaxis Immunization status

Give tetanus diphtheria toxoid?

Give tetanus immune globulin?

Yes

No

No (unless >10 years since booster)

No

Yes

Yes

No (unless >5 years since booster)

No

Clean/minor wound Unknown or 3 doses of absorbed tetanus toxoid All other wounds Unknown or 3 doses of absorbed tetanus toxoid Table 1

initial debridement and surgical stabilization should only take place at specialist centres unless the patient cannot be transferred safely. Other indications for immediate surgery include vascular compromise, requiring repair and revascularization, and compartment syndrome. Lower limb fasciotomy should be performed via a two-incision technique (Figure 1a and b) and must not be delayed. It is important to appreciate that both open and closed fractures are equally at risk from this complication, and the presence of an open wound does not prevent raised intracompartmental pressure from developing.

Debridement Debridement is the removal of foreign material, devitalized soft tissue and bone and necrotic tissue from the wound. The use of a tourniquet should be avoided. The skin edges should be excised and appropriate wound extensions should be made so that all parts of the wound can be adequately explored and the bone ends delivered. The aim is to achieve a healthy, well-perfused and stable tissue bed with a low bacterial count. Skin flaps or undermining should be avoided so as not to compromise vascularity. The viability of muscle is assessed by the four Cs: colour, consistency, contractility and capacity to bleed. The use of fluid irrigation reduces bacterial count; at least 6 litres should be used,8 but only after a clean wound is obtained. The use of high-pressure pulsatile lavage is not recommended as this may damage tissues further or embed contamination into the soft tissues themselves.9 If possible bare bone and exposed articular surfaces should be covered with fascia. The skin should not be closed, although wound extensions performed during debridement can be closed as long as there is no soft tissue tension. An important part of traumatic wound management is the ‘second look’ procedure. This is a further inspection of the wound prior to closure and usually should take place approximately 48 hours following initial debridement. During this procedure, further debridement is performed if devitalized/necrotic tissue has declared itself. Again, a thorough irrigation is performed. If the initial wound is heavily contaminated a ‘third look’ or even more may be required.

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Figure 1 a A cross-sectional representation of the leg illustrating all four compartments. b An illustration of the recommended incisions for fasciotomy and wound extensions in the leg. The subcutaneous border of the tibia is marked in green and the fasciotomy incisions are marked in blue. The perforators arising from the posterior tibial artery are shown in red. (From Standards for the Treatment of Open Fractures of the Lower Limb, by kind permission of BOA/BAPRAS.)

It is important to highlight that it is recommended that senior orthopaedic and plastic surgeons perform these procedures in conjunction, as inadequate initial debridement has been shown to contribute to poor outcomes following open fractures. The use of antibiotic-loaded beads or vacuum foam dressings can be extremely useful in dead-space management, whilst definitive soft tissue cover is achieved (Figure 2). They themselves, however, should not be used for definitive management.

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Secondary closure: healing by ‘secondary intension’ is employed where a wound is left open and heals mainly by the formation of granulation tissue and wound contraction. This process can be lengthy and the cosmetic result is less favourable but is employed where a tissue defect is present and local plastic cover is inappropriate (for example: ulcers and abscess cavities). Tertiary closure: healing by ‘third intension’ involves delayed closure of a wound. The wound edges are left open and then closed after a variable period of time. This technique is used for open fractures and contaminated wounds and requires thorough debridement and wound irrigation as previously described.

Soft tissue coverage Figure 2 The wound edges have been excised and the wound debrided of all devitalized tissues and foreign material in this open tibial fracture. A bridging external fixator has been applied to achieve initial skeletal stability. This will be exchanged for alternative definitive fixation at a later date. Antibiotic-loaded cement beads have been employed to assist in dead-space management.

If there is a soft tissue defect present and soft tissue coverage is necessary and cannot be achieved then many options exist. The simplest method which will yield predictable soft tissue coverage is the most appropriate. The simplest technique for reconstruction is a partial or full-thickness skin graft; however this must be placed on a stable healthy bed of muscle and is not suitable for coverage of exposed bone, tendon or hardware. In these situations local skin flaps, region skin flaps or free tissue transfers may be necessary and highlight the importance of a joint approach of open fracture management with orthopaedic and plastic surgeons. A

Soft tissue cover should be achieved if possible within 72 hours and should not be delayed beyond 7 days.

Skeletal stabilization Loose fragments of bone that are devitalized and have lost their soft tissue attachment and blood supply are removed. Fracture ends and large segments that fail to demonstrate signs of viability are also removed. Major articular fragments are preserved as long as they can be reduced and fixed with absolute stability. Fracture stabilization may consist of temporary spanning external fixation at the time of initial debridement (Figure 2). If this is then converted to internal fixation this should be done as soon as possible. Ideally this can be done at the planned ‘second look’ but should not be delayed beyond 10 days. Beyond this, infection is a risk. Internal fixation with intramedullary devices or plates and screws is safe if there is minimal contamination and soft tissue cover is achieved at the same time as insertion of the implant. Modern multiplanar and circular fixators can be used if there is a significant contamination, or segmental bone loss. When external fixators are used, ‘safe corridors’ for pin placement should be utilized to avoid damaging underlying structures of compromising later plastic surgical reconstruction.

REFERENCES 1 Byrne DJ, Malek MM, Davey PG, Cuschieri A. Postoperative wound scoring. Biomed Pharmacother 1989; 43: 669e73. 2 Culver DH, Horan TC, Gaynes RP, et al. Surgical wound infection rates by wound class, operative procedure, and patient risk index. National Nosocomial Infections Surveillance System. Am J Med 1991 Sep 16; 91: 152Se7. 3 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 Jun; 58: 453e8. 4 Sorger JI, Kirk PG, Ruhnke CJ, et al. Once daily, high dose versus divided, low dose gentamicin for open fractures. Clin Orthop Relat Res 1999 Sep; 366: 197e204. 5 Nanchahal J, Nayagam D, Moran C, Barrett S, Sanderson F, Pallister I. Standards for the management of open fractures of the lower limb. BOA and BAPRAS guidelines, 2009. 6 Patzakis MJ, Wilkins J. Factors influencing infection rate in open fractures wounds. Clin Orthop Relat Res 1989 Jun; 243: 36e40. 7 Rushdy AA, White JM, Ramsay ME, et al. Tetanus in England and Wales, 1984e2000. Epidemiol Infect 2003 Feb; 130: 71e7. 8 Gustilo RB, Simpson L, Nixon R, et al. Analysis of 511 open fractures. Clin Orthop Relat Res 1969 SepteOct; 66: 148e54. 9 Draeger RW, Dirschl DR, Dahners LE. Dt of cancellous bone: a comparison of irrigation methods. J Orthop Trauma 2006 NoveDec; 20: 692e8.

Wound closure There are three types of wound healing which depend on the timing and technique involved: Primary closure: in this method wounds heal by ‘first intention’. The wound edges are approximated without delay and the advantages are that there is a shorter time to healing and the cosmetic result is good. Not all traumatic wounds should be closed in this way due to either the presence of contamination, tissue loss or an underlying bone injury.

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