Internal Fixation In Open Fractures

The use of internal fixation devices in open fractures is a controversial subject, but cases which pose real difficulty for the uncommitted are in practice rather uncommon. The following points should be noted:

1. In children, internal fixation seldom needs to be considered: in most fractures, if angulation and axial rotation are controlled, the remarkable powers of remodelling can usually be relied upon, and an anatomical reduction is only occasionally required. It is useful to remember, as in the adult, that if the wound is more than technical, advantage should be taken of it to reduce the fracture under vision; a stable reduction is often attainable.

2. In the adult, where a fracture is undisplaced, conservative methods of treatment can generally be followed without difficulty; once skin healing has occurred, any secondary procedure can be carried out with comparative security.

3. Where a fracture is unstable, and is open from within out with minimal tissue contamination (Type I open fractures), internal fixation may be carried out in reasonable safety once the wound has been adequately dealt with.

In the case of the tibia, intramedullary nailing with reaming may be undertaken without especial risk of infection in Type II open fractures. In Type 111 open fractures, the use of intramedullary nails is said to carry no greater risks than other methods of treatment, although many would advocate the use of a solid intramedullary nail without reaming, or seek an alternative method of holding the fracture (such as with an external fixator).

In the case of the femur, intramedullary nailing with reaming may be attempted in both Type I and II fractures; but this procedure carries a very high risk of serious infection in Type III injuries, and therefore is contraindicated.

4. Where there has been extensive skin and soft tissue damage or loss, and the wound has been badly contaminated, as a general rule internal fixation should be avoided; the fracture should be supported by a plaster cast or preferably by an external fixator. In the case of the femur, skeletal traction in a Thomas splint may be used. Note that if an external fixator has been applied, and there is no sign of pin-track infection, it may be possible to convert this (if considered to be to the patient's advantage) to intramedullary nail fixation within the first week without there being a greatly enhanced risk of infection. If there has been a pin-track infection, reamed secondary intramedullary nailing is generally contraindicated, the risks of infection being unacceptably high. However, in a few cases, if the pins are removed, pin site debridements carried out, antibiotics administered, and full skin healing obtained and held for some weeks, intramedullary nailing may be reconsidered. Generally speaking, however, when an external fixator is employed, it should be retained until the fracture is united or until a supporting plaster cast can be substituted; alternatively, conversion to llizarov fixation may be a possibility, the fine wires being relatively well tolerated.

Difficulty lends to occur in the handling of the unstable fracture where skin cover is perhaps poor and/or the risks of infection are appreciable but not certain. Against the use of internal fixation in these circumstances is:

1. The risk of wider dissemination of infection into uncontaminated tissue by the greater exposure required for the insertion of some internal fixation devices.

2. The greater risks of wound breakdown.

3. The greater difficulty in obtaining healing if infection becomes established, because of the presence of the fixation device acting as a foreign body.

In favour of internal fixation are the following:

1. The chance of obtaining a good reduction.

2. The possibility of holding that reduction for as long as required.

3. The better prospects of securing bone union and soft tissue healing.

It is also important to note that in the case of multiple injuries the prognosis is best when the circumstances allow early rigid fixation of all lower limb long bone fractures. (This is mainly due to the avoidance of respiratory complications by early mobilisation.) The eventual decision rests on the particular circumstances of the case, and the surgeon's individual assessment of the factors discussed.

Was this article helpful?

0 0

Post a comment