Extremity Injuries and Open Fractures

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A great war leaves the country with three armies – an army of cripples, an army of mourners, and an army of thieves

German Proverb

Although you may have visions of operating night and day in the chest and abdomen in a combat setting, the truth is that you will be dealing with extremity injuries much more frequently than anything else. Because of modern combat mechanisms and improved protective equipment and vehicles, the extremities remain the most vulner-able area to injury (Fig. 19.1). You have most likely dealt with some extremity trauma in the civilian setting, but probably have left most of it to the orthopedic surgeons to manage. In combat you will see extremity injuries unlike anything you have seen

R.C. Rooney (*) William Beaumont Army Medical Center, El Paso, TX, USA

Chapter 19Extremity Injuries and Open Fractures

Richard C. Rooney

Deployment Experience:

Richard C. Rooney Orthopedic Surgeon, Theater Consultant for Spine Surgery, 28th Combat Support Hospital, Baghdad, Iraq, 2007–2008

BLUF Box (Bottom Line Up Front)

1. Know the extremity anatomy. You will be operating on them more than any other body part.

2. If there is any question about a wound, wash it out.3. Adequate washouts of combat wounds are not done in the ER. Do them in the

OR with proper equipment, lighting, and sedation.4. Irrigation, debridement and broad coverage of antibiotics are the key to wound

management success.5. Fracture stabilization is the key to pain control and open wound management.6. Even general surgeons should know how to apply basic external fixation.7. Decisions about amputation rarely need to be made at the first operation.8. Get a second opinion if you are debating amputation and document your

thought process clearly.9. You can quickly place a shunt for major extremity vascular injuries prior to frac-

ture stabilization, and then do the definitive repair with a stable bony platform.

M. Martin and A. Beekley (eds.), Front Line Surgery: A Practical Approach, DOI 10.1007/978-1-4419-6079-5_19, © Springer Science+Business Media, LLC 2011

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in the civilian arena, and you will often not have the luxury of an orthopedic surgeon immediately available to handle it. Review the upper and lower extremity anatomy before you deploy to a combat setting – you will definitely need it.

Combat extremity trauma is not too dissimilar to combat truncal trauma. It is mostly caused by penetrating or blast mechanisms in contrast to the blunt mecha-nisms of civilian medicine. The principles of open wound management such as irrigation and debridement and early antibiotics are perhaps more important in the extremity than the trunk. The simple reason for this is the presence of bone. Bone is slow-growing and slow-healing and its susceptibility to latent infection is more significant than soft tissue.

Anatomy

The first thing to realize as a general surgeon going into combat is that there will be much more extremity trauma than non-extremity trauma. This is simply from the exposed nature of the extremities. So before you do anything, review your anatomy, primarily the vascular system of the extremities. Arterial injury – not bone, muscle, or tendon injury – is what will cause a patient to die in the field or at your facility. Have a good idea how you will gain proximal control of injuries in the various parts of the extremity. Sometimes this even means going into the abdomen to control groin or high leg injuries and into the chest to control shoulder injuries. You should have a clear idea what is going to be the trigger that prompts you to explore the thorax or abdomen to control hemorrhage.

Fig. 19.1 Anatomic distribution of injuries during combat from Operation Iraqi Freedom and Operation Enduring Freedom (Figure courtesy of COL Brian Eastridge, US Army)

25919 Extremity Injuries and Open Fractures

The other surgical anatomy points to review and bring with you are amputation strategies, compartment syndrome releases, and even external fixator placement. Multiple severe extremity injuries are common with combat mechanisms; you may need to use more than one of these techniques on the same patient (Fig. 19.2). If you show up in theatre comfortable with anatomy, the rest of the trauma manage-ment will be based on familiar surgical principles augmented by some basic ortho-pedic expertise that any surgeon can rapidly acquire.

Open Fractures

The keys to success in the management of open fractures are early antibiotics, temporary stabilization, and irrigation and debridement (I&D) until clean prior to closure of wound and definitive stabilization. Early fracture stabilization has multiple benefits in the trauma patient. It will significantly decrease fracture related pain and can often stop bony and soft tissue bleeding. It will decrease the systemic inflam-matory response and may provide protection against fat embolization. In addition, the surrounding nerve and vascular structures will be protected from further injury due to the mechanical instability. Appropriate stabilization is absolutely required before you begin mobilization or transportation to another facility.

There is no consensus on timing for open fracture I&D, timing on fixation, amount of irrigation to use, what type of irrigation, or what, when, and how long to give antibiotics. There is no right answer. What makes sense and is supported to varying degrees in the lab is that the sooner you give antibiotics and the sooner you do an irrigation and debridement, the better. Circumstances will likely dictate whether you are irrigating with power equipment or by hand and with what type of antibiotics are available. There is some current evidence implicating high pressure irrigation (pulse lavage) with adverse wound outcomes, so low pressure irrigation should be your first choice.

Fig. 19.2 Patient injured by explosive mechanism with resultant right traumatic below knee amputation and open left tibial-fibular fractures. Left leg and ankle stabilized with placement of an external fixation device

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Historically, for “dirty” open fractures the recommendations are a first or second generation cephalosporin along with an aminoglycoside. In a “barnyard” setting, penicillin is added. Assume that everything in the modern combat setting is a barn-yard. 2 g Cefazolin q 8 h, 240 mg Gentamicin q 24 h, and 2 million Units Pen G q 6 h was our pharmacy standard in Baghdad.

It is important to take open fractures or potentially open fractures to the OR and wash them out, stabilize them however you can, and start the antibiotics. There is no practical role for culturing acute fracture wounds. Plan on washing open frac-tures out every 24–48 h or arranging for that to be done through the evacuation chain. If you are evacuating the casualty to a higher level of care, do a final washout and debridement the day of transfer. Clearly mark the dressing with the date of the last operative debridement so that your colleagues who receive the patient will be aware.

Often one of the puzzling issues is whether a fracture is truly open or is closed with just a local abrasion. There is a fair amount of disagreement regarding how to treat these. In combat, treat them as open fractures until proven otherwise.

Stabilization

There are all sorts of courses and labs set up for the military surgeon to understand external fixation. The fact is that the evacuation chain is so mature that at some point they will see an orthopedic surgeon with a C-arm available prior to going out of theatre. Splinting any extremity in a reasonable anatomic position will serve the purpose of immobilization as well as allow the potentially inexperienced forward-deployed general surgeon to avoid flailing through an external fixator. However, you should be adept at applying a basic external fixator particularly if you are going to be with a far forward unit or in a very remote location. You will NOT always have an orthopedic surgeon available to guide you.

Splinting is very straightforward. The plaster will typically come in strips about 5 × 30 in. The easiest way I have found to make a splint is to get 10–15 thicknesses and pad it with 3–4 thicknesses of Webril or equivalent cotton padding that comes in rolls. The plaster tears pretty easily when it is dry so figure out what length you need before you get it wet. For instance, for a posterior splint for an arm, you may need to tear the last 5 in. off. Tear or cut it to length. Tear or cut 3–4 thicknesses of Webril for the side that faces that patient and one for the outside. Get room temperature water. Warmer water and normal saline will expedite the plaster cure time but also can create enough heat to burn the patient. Until you get a good idea of the temperature that it will generate, start with room temperature water. As you get more comfortable you may use a little warmer water. The key to slick splint application is having everything set out first. Have Ace wraps ready to go.

Hold onto one end of the plaster in one hand (leave the Webril on the Mayo stand or side – it doesn’t get dipped) and dip the plaster with bare hands in the water. Soak it and then squeeze all the water out. Hold up the splint with one hand from the end

and take the other hand and run two fingers down the splint like a squeegee. Do this to both sides to get all remaining water out. Lay the splint on the 3–4 thicknesses of Webril and cover it with the single layer of Webril. This is your splint, ready to be applied and wrapped with Ace wraps.

If you are splinting an arm, have someone hold the arm and the splint at the wrist and support the splint under the tricep while you roll the ace wrap around it. Cut a hole in the ace wrap if you are wrapping over the thumb and if you fold the splint like a cuff at the ends it will look professionally done. Hold the extremity until it hardens. Be careful not to squeeze too hard as it hardens or you will leave indenta-tions. If you feel compelled to place an external fixator, first ask yourself why a splint won’t work.

External Fixation

External fixators used in the provisional stabilization of combat casualties are typi-cally “spanning external fixators” which gain control of the unstable segment of the limb by inserting threaded Schantz pins into bone remotely above and below the zone of injury, and connecting these pins with carbon fiber or metal rods external to the body to neutralize the forces across the zone of injury, thereby stabilizing it. The minimally invasive nature of this technique also minimizes the risk of infection due to implanted orthopedic devices and allows access to the wounds for follow on care without having to destabilize the limb. The specific steps required to insert Schantz pins into bone vary according to which system you are using, some require pre-drilling others do not – become familiar with the external fixation devices you will have at your disposal downrange and the recommended insertion techniques. Image intensification is desirable, but not required to apply a resuscitative external fixation device.

Schantz pins must be inserted through safe zones of access to the long bones which minimize the risk to the neurovascular structures. In general, these safe zones include the anterolateral surface of the proximal humerus, the lateral surface of the distal humerus about the elbow, the subcutaneous border of the ulna, and dorsal sur-faces of the metacarpals in the upper extremity. In the lower extremity, the anterior and lateral surfaces of the femur are available, as is the anteromedial surface of the tibia, and the calcaneal tuberosity (Fig. 19.3). Despite the relatively superficial nature of these safe zones, major neurovascular injury can occurs at any of these levels in the absence of proper technique. An excellent reference for the deploying combat surgeon who may need to apply an external fixator is The Atlas for the Insertion of Transosseous Wires and Half Pins. Get a copy and put it in your duffle bag.

A minimum of two pins are usually required to gain control of a long bone/limb segment. Insert two pins in the same bone above the zone of injury and two below. Meticulous pin insertion technique should be used: the skin is incised sharply directly over the region of intended pin placement, and sharp and blunt dissection is used to gain access to the bony surface. A saline cooled drill bit is used to drill a

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pilot hole through a drill sleeve utilized to minimize injury to the local soft tissue (some systems use self drilling half pins). The pin is then inserted through the sleeve deep enough to engage the far cortex of the bone and obtain bicortical purchase (Fig. 19.4). Image intensification is very useful in ensuring proper pin placement and depth, but pins can be placed without fluoroscopy if careful attention is paid to local anatomy and the “feel” of the bone on pin insertion. When the tip of the pin engages the far cortex, increased torque is required to insert the pin further. This information along with the knowledge of thread pitch (and therefore how many “turns” are required to advance the pin into bone after initial engage-ment) allows for safe bicortical pin placement without image intensification. After two pins are placed in each bone, they are connected with a multiple pin-bar clamp

Fig. 19.4 Example of a spanning external fixator stabilizing a femur fracture. The inset shows ideal bicortical pin placement (Reproduced from Emergency War Surgery Manual 3rd revision 2004, Borden Institute, Washington, DC.)

Fig. 19.3 Safe zones for pin placement in the femur (a) and tibia (b) (Reproduced from Emergency War Surgery Manual 3rd revision 2004, Borden Institute, Washington, DC.)

or to a bar isolated to that segment, the fracture reduced (under fluoroscopic control if possible), and the two segments connected with additional bars and bar-bar clamps as required. The sequence of pin placement and frame assembly varies according to the experience of the surgeon, treatment goals, and local anatomy. There are several commercially available external fixator devices, each with their own nuances (Fig. 19.5). Find out which you will have and become familiar with them before you deploy. An important step in the application of spanning external fixators is to verify there has been no change in the neurovascular examination after the injury has been reduced and stabilized. When discovered, the etiology of the change in the neurovascular status must be determined and rectified.

In the lower extremity the most practical insertion position of the pins will be straight anterior. Since spreading out the pins will give you the most stability, put them just above the ankle, just below or above the knee and just below the greater trochanter. The position of the fracture will determine where the intervening pins go. The long bones are about 2–3 cm in diameter so once you engage the anterior cortex make a visual cue so you roughly go in that much. You won’t be able to feel the second cortex reliably with the primitive drill that comes with the usual combat orthopedic sets.

Fig. 19.5 Instructions for applying a simple box external fixation frame (Figure courtesy of Synthes Corporation, Philadelphia, PA)

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Add as many longitudinal bars as you need for stability (Fig. 19.6). Remember that you are doing something in a combat environment to save someone’s extremity so don’t be frustrated if your contraption looks silly. Keep in mind that almost every extremity can be splinted adequately to evacuate to an echelon of care where someone has all the equipment to apply external fixators appropriately. So keep things simple.

Example fixation situation: Assume you MUST apply an external fixator to an open tibia fracture. It is safe to put all the pins anterior. The tibial crest is thick so don’t be alarmed if you have to drill 2 cm just to get through it. Pin spread increases stability so you want to put pins as close to the knee and ankle without putting them into the joint and then as close the fracture as you can without going into the frac-ture site. Make a little knick in the skin with a knife and spread down to the bone. Put your pin where you want it and tap it gently. This will create a little divot so your pin won’t spin away from its target when you start to drill. The pin should be solid when it is in. It should feel like a nail in a solid piece of wood. If it seems like it toggles too much, it may not be in the bone or deep enough. The long bones are somewhere between the size of a broom handle and a tennis racket handle. Make sure you drill the pin into a depth somewhat near this. When the pins are in, pull the leg gently straight so it looks reasonably well-aligned and connect all the bars.

If treating a fractured femur, you can place the pins in safely from the side or straight from front to back (see Fig. 19.3). The lateral pins seem to snag on the gurney so anterior is a little more convenient. One difference with the femur is that the bone is deeper. Near the hip, the easiest way to find your pin location is to feel the greater trochanter. A proximal femur fracture can present significant challenges because the proximal part is hard to get a solid anchor point. In this setting it is probably worth taping the legs together instead.

Arm and forearm external fixation is no different except the bones are smaller. For example, if you have done a vascular repair at the elbow and need it to remain stable, you can apply an external fixator from the humerus to the wrist. The distal radius will accept pins directly lateral (pretty easily on the thumb side) and the humerus will accept pins laterally as well. Use the same placement and drilling technique as the lower extremity. Make a little incision, bluntly dissect to bone and then drill. The radius will need a much smaller pin, however, and the thickness of the radius can be very deceiving. Hence, try to stay as shallow in the bone as possible.

Fig. 19.6 Addition of a second longitudinal bar increases the stability of the external fixator construct (Reproduced from Emergency War Surgery Manual 3rd revision 2004, Borden Institute, Washington, DC.)

Feel your own wrist to notice how superficial the bone is under the tendons and how superficial the pin will feel if it is barely under the dorsal cortex of the radius.

Compartment Syndrome: A Contrarian Opinion

You will hear a lot about compartment syndrome and fasciotomies before and during any combat trauma deployment. Most of the discussion will be focused on never missing a potential or existing compartment syndrome. You will hear the recommendation to be extremely liberal about doing fasciotomies, particularly on patients with extremity injury who are being placed into the evacuation chain. Compartment syndrome, in my opinion, is talked about too much. In 6 months in Iraq, I performed no more than a handful of fasciotomies and most of them were not on the leg. However, I have also seen some patients with devastating morbidity due to failure to do a fasciotomy. In these cases it was usually clearly indicated, but overlooked by the managing surgeon.

You must know the anatomy and how to do a fasciotomy before you go. This includes both upper and lower extremity (see Chap. 18). The actual fasciotomy is not too difficult. You incise the skin, and the fascia covering the muscle is a very distinct tissue and the plane is very easy to identify. You make a knick in the fascia and slide your Mayo/Metzenbaum scissors or whatever sharp instrument you choose up the length of the muscle belly.

In the upper extremity, it is a little more involved because the incision potentially crosses the elbow and wrist joints. Nevertheless, open the length of the compartment under direct vision and if it looks like a vessel or nerve, don’t cut it. If it looks like a separate muscle belly that is tight, release it. Know the number of compartments in each section of the extremity, and make sure you have addressed them all. The most common missed compartment is the deep posterior compartment in the calf.

Vessel loops and staples are a popular provisional closure technique. Retention type sutures work as well. Again, there is no right answer. The wound is washed out until ready to close which is dictated by swelling and cleanliness. Skin grafting for coverage is not uncommon, but can be avoided in over 80% of cases by appro-priate attention to wound management and progressive early closure.

I think there are many more fasciotomies performed than really need to be. I don’t think that this is wrong; it just means that some surgeons have a different threshold. You have to use your best judgment. Fasciotomies are not benign and can often complicate prosthetic fitting so it is not something to done without thought. Also remember that often times the injury itself has done an adequate decompressive fasciotomy, and adding additional incisions will only serve to increase the limb morbidity. If the patient has a relatively normal appearing extremity and benign exam, then fasciotomy is usually not necessary. Even among patients being evacuated – the evacuation system is much faster now and with more medical attention paid to the wounded during the entire process. You patient will not sit for days without medical attention, so you can trust that expert eyes will be re-examining the extremity shortly. If the case is borderline or you have doubts, then either do the fasciotomy or keep the patient at your level for another 24 h to watch them closely before transportation.

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Nerve and Tendon

You will frequently encounter injured nerves and tendons during your exploration and debridement of extremity wounds. Sometimes it is difficult to tell tendon from nerve; the best way is to look directly at the cut end (after debriding devitalized segments). Nerves will be yellow-white and contain multiple round fibers while tendons will be blue-white and have crosshatching (like wood). These are typically massive wounds with significant contamination and non-viable tissue, so there is not really a role for immediate primary repair. Tendon repairs can wait until the wound is cleaner, and most combat nerve injuries will be repaired in a delayed fashion. Always leave hand tendon repair for someone with adequate training. Tag the ends of the nerve for easy identification later.

Occasionally you will encounter a very clean and sharp major nerve transection suitable for immediate primary repair and no orthopedic or neurosurgeon immedi-ately available. Common examples are median or ulnar nerve transections (often associated with brachial artery injury). Make sure you align the nerves properly, sharply debride the ends, and reapproximate the epineurium only using fine prolene or nylon sutures (Fig. 19.7). Ensure adequate tissue coverage of the repair and you may need to splint the extremity in flexion to prevent tension on the repair. It will take months to determine the success of repair and ultimate degree of return of function.

Fig. 19.7 Technique of epineurial primary nerve repair. The ends of the nerve are sharply debrided (a), two stay sutures are placed (b), anterior (c) and posterior (d, e) approximating sutures are placed, and the anastomosis is completed with multiple interrupted sutures (f). Note that sutures pass through the epineurium only (g) (Reprinted with permission from “Injuries to Vessels, Nerves, and Tendons” in Primary Surgery Volume 2, German Society for Tropical Surgery 2008, illustration by Peter Bewes.)

Final Thoughts

Don’t lose sight of the fact that the first trip to the OR often is for resuscitation and stabilization. Don’t prolong a trip in the OR to chase every little laceration and piece of charred tissue. Get them in, get them stabilized and get them out. If they are grossly contaminated you may have to bring them back in 24 h or less. Think of the patient as a whole. There are no gurus of combat surgery. Most surgeons in combat are within 5 years of their residency. It is harrowing and unfamiliar. Prepare, be definitive and do your best

Extremity Injuries and Open Fractures

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