The Colles' fracture results from a fall on the outstretched arm (The Smith's fracture from a fall on the bent wrist), the patient experiences severe sudden pain and there is often obvious deformity of the wrist associated with angulation of the bones. Colles' described this as a "dinner fork" deformity, as this is just as it looks. The wrist is examined to ensure the blood supply and nerve supply is in tact, the latter can cause numbness of the fingers and is not uncommon after these fractures.
The wrist is then X-rayed and generally there are three features:
- Dorsal angulation (angulation of the fragment towards the back of the hand).
- Radial angulation (angulation of the fragment towards the thumb).
- Impaction (shortening of the bone as the fragments collapse into each other).
There are many classifications of wrist fractures, some of which are useful and some not. The most important factors are:
- Fracture displacement - how out of alignment it is on the X-ray
- Radial shortening - due to impaction the bone can shorten
- Intra-articular/Extra-articular - if the fracture goes into
The joint, it is more serious and an operation is more likely.
- Fracture stability - an unstable fracture is difficult to maintain in a good position an operation is more likely.
The fracture must be reduced (the bones re-aligned) and held in position. The can be done by non-operative or operative means.
Under some form of local anaesthetic the wrist is manipulated straight (the local anaesthetic can be put directly into the fracture site or can be via a Bier's block. The latter is where the blood is drained from the hand by elevation and tourniquet applied and then the veins in the hand are filled with local anaesthetic). The deformity has first to be worsened before it can be bettered. The wrist is put in a below elbow cast and an X-ray is taken to confirm the position. The arm is then elevated in a sling, advice given about movement of the fingers, elbow and shoulder. Generally another X-ray is taken in the fracture clinic at one week. The cast is normally maintained for 6 weeks.
If the fracture is unstable, displaced, intra-articular (into the joint), in lots of pieces, or the radius is very short then operative treatment may be advised. Also if the fracture that was treated initially conservatively, when X-rayed at a week, is found to have lost position then further conservative treatment is a waste of time.
The operative options are:
All require anaesthetic of some kind (see anaesthetic). Pinning involves manipulating a fracture and then passing 3 or so pins (known as K wires) across the fracture as an internal splint. These wires are generally buried under the skin and left for 6 weeks. This form of treatment is obviously easier for the patient, but a cast still has to be worn for the 6 weeks and a further minor procedure is necessary to remove the wires.
- Percutaneous pinning
- Dorsal plating
- Volar plating
Plating involves putting a metal plate on the back (dorsal) or front (palmar side) of the bone. Both these are more extensive operations than the pinning and hence may have more complications, however the advantages are stabilising the fracture in a more rigid fashion and hence the possibility of reducing the time necessary in a cast.
Mr. Field is an advocate of Volar plating rather than dorsal, because the tendons on the back of the wrist are more difficult to rehabilitate after the operation.