Mechanism of fracture

A fracture can be caused either by direct violence or indirect
violence. Direct violence causes a fracture at the site of impact of the force.
Indirect violence fracture is one that is transmitted to a bone away from the
site of impact and producing the fracture there.

Torsion produces spiral or oblique fracture. It is important to understand the mechanism of fracture as it helps in deciding the manoeuvres for reducing further damages. When a man falls down from a building or from a coconut tree he sustains a fracture on bones and the spine. The fracture of bone is caused by direct violence and the fracture spine is caused by indirect violence.

Healing of Bones in fracture

It involves three phases, viz.,
1. Inflammatory phase 2. Reparative phase and 3. Remodelling phase.

1. Inflammatory Phase

When a fracture occurs, at the site of fracture the blood vessels get broken and the blood fills up the gap of the bone. This blood clots to form a haematoma. This process takes place in one to two days. The soft tissue of this region undergoes inflammation.

2. Repairative Phase

A stage of callus is formed. It bridges the gap and establishes contact between the ends of fractured bone. The callus is nothing but granulation of tissues around the site of fracture. This phase takes place about eight to twelve weeks.(Fig. 1.7)

3. Remodelling phase

Once the fracture is bridged by the callus tissue, the site of fracture undergoes remodelling by muscular and weight bearing stresses and slight deformity gets corrected by moulding. This remodelling takes up to one year.

Physiotherapy and rehabilitation

Physiotherapy is the therapaeutic exercise to make the limbs work
normally. Therapaeutic exercise is carried out by physiotherapists under the supervision of orthopaedic surgeon. The commom problem at the end of
fracture treatment is the wasting of muscles and stiffness of joints. These
two problems can be rectified by physiotherapy, by gradual exercises.