Introduction

A fracture is defined as a disruption in the integrity of living bone. It involves injury to bone marrow, periosteum, and adjacent soft tissues. Fractures can be classified as closed or open. In closed fractures the enveloping skin and soft tissue are intact but the area may be bruised and swollen. When fractures are classified as open, the integrity of the skin is lost and the fracture haematoma communicates with the external environment. In a complete fracture, the bone is broken completely into two or more fragments. In an incomplete fracture, the bone is divided but with periosteal continuity remaining. In a greenstick fracture, seen most commonly in children, the bone is buckled or bent. Intra-articular fractures are those where the fracture line involves the joint.

Fractures are also described in terms of the fracture patterns, such as transverse, oblique, or spiral. In comminuted fractures there are more than two broken fragments. Compressive forces may result in impacted or crush fractures; avulsion fractures are caused by traction forces, and spiral or oblique fractures are due to rotational forces. Fracture segments are defined by looking for displacement (described as: translation, angulation or tilt, and finally rotation). If a trivial force was needed to produce the injury then a pathological fracture must be ruled out as the bone may be diseased with osteoporosis, Paget's disease or malignancy (primary or secondary).

Fracture healing

Occurs in four different stages (Figure 54):

1. Haematoma formation

2. Granulation tissue and soft callus formation

3. Bony callus

4. Bone remodelling.