Month: January 2011

Dr Amy Hughes, Medical Director of Expedition Medicine and Pre-Hospital Emergency Medicine Registrar with Kent Helicopter Emergency Medical Team gives a brief overview of managing femur fractures in an expedition environment, in the first article in a series examining  pre-hospital expedition trauma care and associated kit..

Management of a mid-shaft fractured femur in the field and use of the Kendrick Traction Device

Expeditions have become more and more adventurous over the past years, both in destination and the participants involved. As a result, the frequency and pattern of injury is changing and the demand on the medical team thus increased. Having a broad knowledge of fracture management, including mechanism of injury, clinical findings, reduction techniques and splinting is essential.  Although one of the most enjoyable challenges of being a medic on an expedition team is improvisation regarding kit used to manage various ailments and injuries, practice and competence in the use of non-improvised kit such as the Kendrick Traction Device is vital.

Mechanism of injury

Fractured femurs form only a small percentage of common injuries on expeditions but can be associated with significant morbidity and mortality. Early effective management is vital in view of the risk of significant blood loss, pain, long term complications and compartment syndrome. In assessing and managing femur injuries, it is also very important to exclude associated injuries such as chest, axial skeleton, pelvis and head. This article will focus only on mid shaft femur injuries, further discussion on management of multi-trauma will be examined in another article.

A high energy force is often needed to fracture the femur in a young, fit individual unless they have a pre- existing medical condition predisposing them to reduced bone density (osteoporosis, malignancy, malnutrition, muscle atrophy, previous fracture). Road Traffic Collision are the one of the most common risks to participants on an expedition and a common mechanism for high energy transfer resulting in fractures of the femur – especially dashboard injuries. Other mechanisms of injury include falls from height, pedestrian versus vehicle and direct trauma to the leg. As mentioned above, associated injury need to be considered and managed appropriately, especially pelvic injuries.

Mid shaft femur fractures

These fractures are almost always the result of high energy trauma, the mechanisms of which have been mentioned above. As the femur is very vascular, injury can result in significant blood lost and a requirement for haemorrhage control and clot preservation pre-hospitally until definitive care can be reached is paramount. The pattern of femur injury often results from the direction of force applied. For example, a perpendicular force results in a transverse fracture pattern, an axial force may damage the knee or hip and rotational forces may cause spiral or oblique fracture patterns ⁽¹⁾ . Again, understanding the mechanism of the injury is fundamental in determining the resultant pathology. Further complications from mid-shaft femur fractures include deep vein thrombosis, fat emboli, nerve palsies and rarely compartment syndrome.

Clinical Features

Pain is the initial most significant feature. The leg may be shortened and rotated and/or visually deformed with swelling and fullness to the thigh. If the injury is compound (or open) then there will be a wound over the fracture site communicating with the bone / bony fragments. The person will be unable to weight bear. A neurovascular assessment should always be done, with distal pulses felt (often worth marking the pulse with an ink cross) and distal perfusion monitored both after the initial injury, following any intervention and throughout the course of the casevac.

Management

It is vitally important to ensure there are no other traumatic injuries, and an ATLS management approach to the patient should be made.

The ultimate aim of management of a femur fracture is to return the limb to its normal anatomical position. This not only helps reduce pain by bringing the bony fragments into alignment and reducing muscle spasm and soft tissue involvement, it also reduces bleeding, improves clot preservation and helps improve distal perfusion. In the pre-hospital expedition environment resources are limited but if there are no formal traction devices available, improvised devices can easily be used.

Traction is needed on the limb to help bring the proximal and distal ends of the fracture back into alignment, reduce bleeding and pain.

Steps to management of mid shaft femur fractures on an expedition

ANALGESIA – depending on what you have available:

1. Paracetamol
2. NSAIDs
3. Morphine.

IRRIGATION

1. If the injury is a compound fracture (open) or has a wound associated with it, it must be irrigated. This does not have to be done with sterile water – water from drinking bottles or taps can be suitable for preventing wound infection ^{(2, 3)} . The wound must be irrigated thoroughly to reduce the risk of infection. It is likely that it will be some length of time before the injury is dealt with in definitive care and re-irrigated. This applies to any wounds sustained to the patient. A dressing can be applied to the area. Irrigation can be undertaken at the same time as traction is being applied.

TRACTION

1. The leg needs to be put under traction. Whilst kit is being assembled, the leg can be held in traction by any member of the team. The foot and ankle can be held, and the leg pulled out to anatomical alignment and held in position. This is immensely painful for the patient, and thus adequate analgesia is essential. Once the leg is under traction, pain is often reduced.
2. Kendrick Traction Device Use: The Kendrick Splint is an excellent lightweight piece of kit used widely in pre-hospital care and expedition medicine. It is easy to use, effective and relatively cheap. The pictures below demonstrate correct use of the splint:

The Kendrick Traction Device (KTD). Lightweight and very effective. Approx weight 0.5kgThere is also a boot hitch strap (see final images)

Step 1:

Place upper thigh strap high into groin with the pole holes on the outside of the leg. This strap must sit as high as possible. Measure out the length of the pole against the leg. The bottom of the pole should extend approximately one section length below the foot. The pole can be shortened and lengthened in a similar manner to a tent pole.NOTE : Manual inline traction of the limb should be undertaken as soon as possible and throughout the KTD application

Step 2:

Example of manual in-line traction of the limb.Prior to the ankle strap being positioned, the yellow Velcro strap can be applied just above the knee. This may need tightening after traction has been applied.

Step 3:

Apply ankle strap. The padded part of the strap sits behind the ankle. Tighten using the green strap. The yellow strap fits over the pole end (black part) and traction can be applied gently by tightening the red strap. Traction should be applied until the leg is comfortably under traction and in anatomical alignment. Check distal perfusion.

Step 4:

Whilst pulling the red strap, a small amount of counter traction needs to be applied to the KTD

Step 5:

Apply the two other Velcro straps…..the red strap at the top of the thigh, the green on the lower leg. Manual in-line traction can now be released.

Step 6: Boot hitch

The KTD comes with the option of a boot hitch which can sit over a walking boot if the decision is made not to remove the shoe. The boot hitch strap is laid under the ankle, the white label on the inside of the strap lying closest to the boot.

Step 7: Boot Hitch

The hook is done up over the boot

Step 8: Boot hitch

The same process as per the ankle strap can then occur, although there are only two straps – the yellow attaches over the end of the pole, the red strap is used for tractioning the splint with a small amount of counter-traction.

Other splints:

i.      Sager traction splint – this is bulkier to carry as part of an expedition medical kit but is effective and allows traction of both femurs simultaneously.

ii.      Improvised splints

Walking pole or sturdy wooden stick braced and secured to either side of fractured limb (the outside length up to the pelvis, the inside length up to groin) and extending a good 15cm below the ankle. A cross pole positioned across distal end of the poles below the ankle and tied into place. A figure of eight strapping around the ankle, extending down over the cross pole and tightened on itself thus pulling traction down the length of the leg. Alternatively, the figure of eight strapping can be tied to the cross bar and a small piece of wood or metal can be used on the length of strapping between the foot and the cross bar to twist the strapping and tighten the traction on the limb. Important to ensure traction is comfortable and foot remains perfused with a good distal pulse.

The injured leg splinted against the non-injured leg using a walking pole or sturdy stick and strapping (crepe bandage, clothing, rope). This doesn’t allow for traction but may be the only option available to provide some comfort to the patient prior to evacuation.

IV FLUIDS

Providing the patient is cerebrating and has a good radial pulse, intravenous fluids are not required unless there are significant signs of haemorrhagic  shock. Permissive hypotension is not discussed in this article and further reading is advised regarding the changes and advances in fluid management in trauma. Do not run 2 litres of fluid into the patient!!

IV Antibiotics for compound (open) fracture and Tetanus prophylaxis

Open fractures are tetanus prone wounds, and most participants on expeditions should be up to date with there tetanus vaccinations. However, it is vital to check with the participant when their last booster was and documenting it for handover when definitive care is reached. If a patient is not vaccinated, of if they are unsure, the vaccine should be administered. The current UK guidelines state that a patient is considered Tetanus immune if they have received five doses of vaccine in their lifetime ⁽³⁾.

Intravenous antibiotics should certainly be considered in the expedition environment. A Cochrane systematic review of the use of antibiotics in open fractures as an adjunct to irrigation and further care found that administering antibiotics did reduce the incidence of early wound infections ^{(3, 4)} . Depending on what you carry, a first generation cephalosporin can be used.

References

1. F. Gaynor Evans; Herbert E Pedersen, H.R Lissner; The role of tensile strength in the mechanism of femoral fractures; Journal of Bone and Joint Surgery, 1951; 33; 485 – 501
2. Fernandez R, Griffiths R 2008; Water for wound cleansing. Cochrane Database of Systemic Reviews, Issue 1, CD003861
3. Barnard AR, Allison K; The Classification and principles of management of wounds in trauma. Trauma 2009; 11; 163-176
4. Gosselin RA, Roberts I, Gillespie WJ; Antibiotics for preventing infection in open limb fractures; Cochrane Database of Systematic  Reviews 2004, issue 1, Art No CD 003764