Contents
Introduction
Permanent failure of healing following a broken bone unless intervention (such as surgery) is performed.
Classification
- Septic nonunion
- Pseudoarthrosis
- Hypertrophic nonunion (by inadequate stability with adequate blood supply and biology)
- Abundant callous formation without bridging bone
- Typically heal once mechanical stability is improved
- Atrophic nonunion (by inadequate immobilization and inadequate blood supply)
- Oligotrophic nonunion (by inadequate reduction with fracture fragment displacement)
Aetiology
Risk factors:
- Old age
- Poor nutritional status
- Nicotine and alcohol consumption
- Hyperparathyroidism
- NF1 genetic predisposition
Diagnosis
Radiography:
No healing between two sets of X-ray (generally after 6–8 months)
Management
Surgical management:
- Surgical removal of all scar tissue from between the fracture fragments
- Immobilization (with internal/external fixation)
- Autologous bone graft (GOLD STANDARD) (graft bone obtained from iliac crest) (osteoinductive)
- Bone is the only tissue that can heal without a fibrous scar
Conservative management:
- Fracture brace immobilization
- Weight-bearing:
- In some circumstances and special patient characteristics (e.g., elderly patients not eligible for operative treatments), nonunions can be treated with weight-bearing and watchful waiting.
- Weight bearing can be coupled with operative methods such as dynamization or bone excision
- Bone stimulation:
- Electrical stimulator/electromagnetic fields: Growth factors are stimulated in response to the electric and electromagnetic fields
- Ultrasound (low-intensity pulsed ultrasound [LIPUS]): Low sine waves will promote bone healing by increasing the osteoblastic response