Bone Cyst: Bone Tumour? Easy MBBS
- Bone Cyst occurs mostly in children (one of the common bone tissue disease)
- In the metaphysis of one of the long bones
- Occasionally in the small bones (adult carpus)
- Bone Cyst is not a tumour (Non-neoplastic bone disease)
- Heals spontaneously and seldom seen in adult
- It is discovered after a pathological fracture or as an incidental finding on x-ray.
Pathology of Bone Cyst:
It begins as a spherical lesion but as it enlarges it tends to become oblong. It tends to lie centrally rather than grow eccentrically. The remaining cortex may appear expanded in all direction. The lining membrane consists of flimsy fibrous tissue and often containing giant cell. After a pathological fracture, the lesion often heals spontaneously.
Clinical Features of Bone Cyst:
Symptom less-Unless a pathological fracture occurs.
X-ray of Bone Cyst:
Well demarcated radiolucent area in the metaphysis, often extended up to the metaphyseal plate. The cortex may be thinned and the bone expanded.
Differential Diagnosis of Bone Cyst:
- Non ossifying fibroma
- Fibrous dysplasia
- Cartilage tumour
Investigation of Bone Cyst:
Needle inserted under x-ray control. The straw colored fluid will be withdrawn.
Treatment of Bone Cyst:
Asymptomatic lesion:
Left alone.
Advised to avoid injury.
Active bone Cyst: Sequential x-ray shows the cyst is abutting against the physical plate.
- Aspiration
- Injection Methylprednisolone 80-160mg
- Autogenous bone marrow.
Bone Cyst with pathological fracture:
- Cavity cleaned by curettage and packed with bone chips. Care should be taken not to damage the epiphyseal plate.
- Prophylactic internal fixation can be done.
- There is the risk of cyst recurrence. More than one operation may be needed.