How to apply a cast for forearm fractures.

Abstract

The forearm bones (radius and ulna) are the two most commonly broken bones in the body.1 Immediate management of these injuries includes applying a plaster cast—called a back slab—to the dorsal aspect of the forearm. These casts are a simple and effective way of providing temporary stabilisation of the fracture and pain relief. All medical students and junior doctors should know how to apply a dorsal back slab.2 It is usually applied in the emergency department or orthopaedic theatre, but it might also be required during expeditions or in remote settings on elective placement. The back slab bridges the gap in treatment until definite fracture fixation takes place—that is, an operation is planned within a few days or a full circumferential cast is applied once swelling has settled. In both cases, a fracture of a forearm bone will take about six weeks to heal. It is important that a back slab does not encircle the limb to allow for some expansion secondary to swelling, and it should be easy to remove. A back slab can be applied with or without manipulation of the fracture, and it can play an important part in managing a fracture conservatively. However, application of the back slab is not without its risks. Circulatory or nerve impairment can occur if a back slab is applied too tightly, and pressure ulcers can develop if padding at bony prominences is not applied appropriately.23 Practice is all that is required to become proficient in applying a cast, and the fracture clinic or emergency department plaster room can be a source of training and support. The principles learnt from casting the forearm can be applied to other parts of the body. The British Orthopaedic Association’s patient liaison group states that they expect that anyone who requires …