Basic principles of treatment

Certain principles must be followed when treating conditions of the hand and wrist.

Avoiding swelling and stiffness

The hand swells following injury, surgery or infection (Fig. 30.1); as it swells it tends to fall into a position with the wrist flexed, the metacarpophalangeal joints extended and the interphalangeal joints flexed. This position becomes perma­nent as the collateral ligaments shrink and the oedematous tissues fibrose. The hand then cannot function properly. To avoid this, one must obey the following three principles.

1.Elevation. The hand must be elevated in a high sling or roller towel (Fig. 30.2), care being taken that the venous drainage is not occluded by too much elbow flexion.

2.Splintage. The wrist should be splinted initially in the position of safety — the ‘Edinburgh’ position described by James (Fig. 30.3). Dressings must not be too tight.

3.Movement. As many joints as possible of the wrist and hand should be moved as early as possible. Rehabilitation should be planned so that the fewest possible joints and tendons are immobilised.

Anaesthesia

Many procedures on the wrist and hand can be performed using local anaesthesia either proximally (scalene block, axillary block) or more distally (Bier’s block, wrist block, digital nerve block or tendon sheath block). In general, if a tourni­quet is used for more than about 20 minutes it becomes un­comfortable and so a proximal block or general anaesthetic is preferred.

For a digital nerve block, local anaesthetic is introduced into the palm at the level of the distal palmar crease; this is preferable to surrounding the base of the finger with a poten­tially occlusive ‘ring block’. An alternative is to instill about 1 ml of 2 per cent lignocaine beneath the flexor tendon sheath. This takes a little more time to work than a digital nerve block, but lasts for longer and is equally effective.

Tourniquet

A bloodless field is essential for accurate surgery. A well-padded tourniquet above the elbow, inflated to 75 mmHg pressure over the systolic blood pressure, is usually satisfac­tory. The time should not exceed 2 hours. An Esmarch bandage or a rubber-tube exsanguinator are effective, but should be avoided for tumour or infection cases lest the pathology is spread systemically. In the finger, a tourniquet can be made by placing a sterile glove on the patient, snipping off the tip and then rolling the glove down to the base of the finger.

Incisions

Incisions which cross a flexion crease may produce an un­comfortable and restrictive contracture. Therefore, surgical incisions should be planned to cut across flexor creases at 450 or to lie in neutral areas, such as the midlateral line of the finger. An alternative is to close a straight incision across a flexor crease with a Z-plasty (Fig. 30.4).

Splints

Splints can broadly be described as resting, static or dynamic (Fig. 30.5). Resting splints are used to immobilise the hand when there is active inflammation, for example after injury, after surgery or during a flare-up of rheumatoid arthritis or infection. Static splints can be used continuously (e.g. for a fracture until healed), serially (e.g. gradually changing the angle of a splint to overcome a joint contracture) or period­ically (e.g. a wrist extension splint at night to reduce symp­toms of carpal tunnel syndrome). Dynamic splints allow movement of one group of tendons but not the antagonist, for example to protect either the flexor tendons or extensor tendons after repair.