Common Tread

Ask the doc: Did Spurgeon and friends handle the leg fracture the right way?

May 01, 2018

We recently learned of Spurgeon’s friend’s ill-fated off-road wreck at the junction of public and private land. While we were all glad he was safely rescued and no one was arrested, his injury and readers' comments raised a few key issues that are worth exploring.

  • If you fracture your leg below the knee, should you remove the boot to look at it?
  • Should you brace the boot to limit motion at the ankle joint?
  • Are there risks if getting to care is going to be prolonged?
  • When should you call for helicopter rescue?

These all have mostly straightforward answers.

First, let's assume that you or your riding buddy went down and heard or felt the proverbial crack somewhere between your knee and your ankle. We will also assume that you have purchased excellent gear (from of course!) and are sporting a fine pair of off-road boots. This leaves your fractured lower leg encased in a helpful boot splint. There may be a period of little pain that will tempt you to remove your boot and see what has happened. This is a bad plan, a very bad plan.

x-ray of broken tibia
This X-ray of a fractured tibia shows how bone fragments can be created. Movement of the leg can cause more damage as those fragments shift inside the broken leg. Photo from open access case report.
First, it will remove the support you have for whatever is fractured, allowing the fragments to move around. This will hurt — a lot. It may also induce bleeding or worsen any bleeding that already exists, since the edges of the fragments are sharp. Also, you may pass out from pain or just from seeing pieces of bone protruding through your skin (also known as a vagal reaction). If this happens, lie down as a means of helping your blood pressure recover.

When you awaken, or you buddies awaken you, they will need to resplint your broken leg, likely by putting it back into the boot. This will hurt much more, and there's the risk of not being able to drive your leg back into the boot, as well. While an external splint can be fashioned, the boot also helps limit heat loss, and due to its non-expansile nature, may limit blood loss, too. For all these reasons, leave the boot in place.

Second, if you must be moved by your buddy and not by trained professionals using a stretcher by ground or air, splinting the ankle joint is reasonable. So is splinting the knee joint. In general, we immobilize the joint above and below a fracture to limit motion and minimize additional injury across the fracture line(s). Clearly knee immobilization would not have worked for Spurgeon’s buddy, as he was ridden out as a pillion passenger. It would have been reasonable to limit motion at the ankle more than the boot already did. Judicious use of duct tape to help prevent the flexing at the ankle (point the toes) can be helpful in terms of stabilization.

If you're not wearing great off-road boots and have a lot of flexing ability throughout, external splints along either side of the boot and across the ankle, secured with duct tape, rope, or even Rok straps, can be useful in stabilizing the fracture site. Swelling of the lower leg as a result of the injury will also occupy space within the boot and be a temporary aid, as well. Be aware, swelling is also potentially dangerous. This leads to the third point.

Prolonged extrication and rescue does carry important risks, and they are often highest with fractures that do not puncture the skin (aka “closed fractures”). As a result of the blunt forces, the fracture and the bleeding into the surrounding tissue, the spaces in your lower leg can come under a lot of pressure. There are four such spaces that we call compartments. Each compartment has muscle, blood vessels and nerves. Your muscle gets blood and oxygen as a result of the blood pressure in the very small blood vessels being higher than the pressure in the tissue. With injury, bleeding and swelling, the compartment pressure can rise and ultimately be higher than the pressure leading into the compartment. As a result, there is not enough oxygen to keep the tissues alive and they start to die. This is an emergency and is the lower leg fracture equivalent of a heart attack. With a heart attack, minutes are essential, and with compartment syndrome, hours are important.

The treatment is to relieve the pressure by opening up the compartment and allowing blood to flow as it should once again. Does this happen to everyone with a lower leg fracture? Absolutely not. It is however, hard to predict to whom it will happen. After about six hours of poor blood flow, muscle viability is seriously threatened, even with restored blood flow. Worse, the restored blood flow can create its own injury, called reperfusion injury! Clearly, early stabilization helps limit bleeding and can help limit swelling, as well.

If there is a lot of bleeding that rapidly flows over the top of the boot, you have a life-threatening emergency. Still, leave the boot in place. Remember that tourniquet for your emergency kit? Here is where you use it. This should also prompt rapid rescue by the fastest means possible, be it by ground or air.

off-road boots
Off-road boots provide a lot of support. If the leg inside is broken, don't take the boot off to look at the injury. Photo by Spurgeon Dunbar.

Fourth, when should you call for air ambulance evacuation? This one is a bit more difficult and straightforward all at the same time. This kind of rescue is not cheap, but can be lifesaving for those in difficult-to-reach places (no roads, on a mountainside, etc.), when ground transport is not available in a reasonable period of time (think I-95 traffic jam after a bridge collapse), and when there are life-threatening injuries where air transport time is significantly less than the available ground transport time (long distance to the nearest trauma center). Of course, when there is truly foul weather, air ambulance evacuation is generally not available and conventional rescue is your sole option.

Regardless of how you are rescued, remember that the EMS workers who have come to your aid also embrace some degree of risk, whether it is a high-speed race to the ED or a dangerous rescue in a confined space leading to helicopter transport. If you have been the recipient of their care, remember to thank them every opportunity you get. You never know when you will need them next!