Progressive, double-blind, randomized pragmatic study of the effect of the plaster casting position in the treatment of a distal radius fracture

Treatment of bone fractures by immobilization, i.e. by supporting the broken limb against an external support, has its roots in ancient history. Even today, fracture treatment is attempted conservatively without surgery, i.e. by immobilization, if at all possible. Fractures of the lower part of the radial bone are very common, especially among the older population. Conservative treatment of these patients is recommended, because the risk of open reduction and surgery grows as the patient becomes older and sicker. Despite the centuries-old tradition of conservative therapy for the fractures of the lower part of the radial bone, we still do not know what is the most optimum immobilization or casting position of this fracture type.

Historically, the most common position is probably the so-called “Cotton–Loder position”, i.e. maximal flexion of the wrist and turning the palm of the hand toward the ulna. The casting position was described in literature already more than 100 years ago, in 1910. Later, however, it was discovered that this combination of two extreme positions exposes the median nerve to a clamp and thereby to further problems. About half a century later, British orthopaedics and traumatology pioneer Sir John Charnley published a fracture treatment guide, which is still one of the defining works of fracture treatment. In terms of treating fractures of the lower part of the radial bone, he recommended a mild flexion of the wrist and turning the hand toward the ulna. The position was therefore similar to “Cotton–Loder,” but tried to avoid extreme positions. The particular casting guide described by Charnley has been preserved to this day as the most widely-used casting position in the treatment of wrist fractures in, for instance, Finland.

Despite the avoidance of an extreme position, this casting position is associated with a number of problems, such as stiffness of the triceps tendons of the fingers. Wrist flexion and turning to the ulnar side prevents the active extension of fingers during plaster treatment, which may result in significant small joint stiffness and pain. This is highly common particularly in the target group of conservative treatments, i.e. among older patients, due to the wear of joints and tendons already before the fracture. Moreover, avoiding extreme positions does not entirely eliminate the development of a clamp of the median nerve.

When plastering a fracture of the lower part of the radial bone, other plastering positions have been used, of which the so-called functional position has recently been favoured. In this method, the wrist is placed in a light extension and in line with the forearm. There are only so-called low-screen studies, i.e. descriptive or retrospective comparative studies, on the treatment of different plastering positions. There are no so-called high-screen studies or randomized, blinded studies on the subject.

Due to the varying treatment practices and a lack of high-quality research evidence, our study aims to be “a progressive, double-blind, randomized pragmatic study of the effect of the plastering position in the treatment of distal radial fracture” to examine the best possible plastering position of the fracture of the lower part of the radial bone in conservative treatment.