Page 166 - ASOP ROT Study Guide
P. 166
Initially, external fixators were designed to be removed once the soft tissues healed and fracture
treatment continued by other means. It is possible to go on to treat the fracture definitively with a
fixator, particularly if the fixator can be adjusted in the later stages to permit some movement at the
fracture site. However, there are still problems, particularly with the pin sites which are an easy
route for infection, a common and often problematic complication.
7.5.3 Internal fixation
Where a high degree of accuracy is required, or other methods fail, internal fixation of fractures is
generally used. Internal fixation involves the holding of the fractured bone with devices such as
screws, nails or plates.
To the beginner the question must come "why not internally fix all fractures?" This will be
discussed at length below. Suffice it to say at this stage that internal fixation of fractures is
technically very demanding, it has many complications and, most important of all, it prevents
natural healing.
If internal fixation is to be used it can be achieved in a number of ways:
♦ Apposition
♦ Interfragmentary compression
♦ Interfragmentary compression plus onlay device
♦ Inlay device
Apposition
Once fractures are realigned they may only need to be held in apposition (i.e.. together in
alignment) for healing to proceed satisfactorily. This is particularly true in children, and can
be achieved simply by using semi-flexible wires known as K or Kirschner wires (see Figure
22). They hold position without producing immobility and so healing occurs by natural callus
formation. They can be left standing proud of the bone and so can easily be pulled out once
union is established and before consolidation.
www.raddaily.com
FIGURE. FRACTURE AROUND THE ELBOW IN A CHILD BEFORE AND AFTER FIXATION WITH
"K" WIRES.
Interfragmentary compression
This consists of holding two bone fragments firmly together. Interfragmentary compression is
usually achieved by screws (Figure 23) or occasionally by tension band wires.
