Bone Cyst


Differential diagnosis of a solitary bone lesion (A very High yielding Table for MD Entrance)


Giant cell Simple bone Aneurysmal Fibrous
tumour cyst bone cyst dysplasia

•     Age

20-40 yrs. < 20 yrs. 10-40 yrs. 20-30 yrs.

»    Common

Lower femur, Upper humerus Tibia Neck of the femur


Upper tibia Upper femur Humerus Tibia
Lower radius

•     Location

Epiphysis Metaphysis Metaphysis Metaphysis

•     X-ray

Soap-bubble Maximum width Distending Multi-loculated
appearance, less than width lesion, Ground-glass
eccentrically of the growth plate ‘ballooning’ the bone appearance
placed Trabeculations++

•     Treatment

Excision Curettage Curettage Curettage


and bone graft and bone graft and bone graft


    • This is the only true cystof the bone
    • ends of the long bones arc the favourite sites
    • commonest site being the upper-end of the humerus (MCQ)
    • X-rays show a well-defined, lobulated, radiolucent zone in the metaphysis or diaphysis of a bone
    • Maximum width of the lesion is less than the width of the epiphyseal plate (MCQ)
    • Treatment:
      • The cyst is known to undergo spontaneous healing, particularly after a fracture.
      • One or two injections of methylprednisolone into the cyst results in healing.
      • Some cases need curettage and bone grafting
  • Anuerysmal bone cyst
    • a benign bone lesion
    • consists of a blood-filled space enclosed in a shell, ballooning up the overlying cortex – hence its name.
    • common between 10-40 years of age. (MCQ)
    • Common sites are the long bones, usually at their ends.
    • A gradually increasing swelling is the predominant presentation
    • There is little pain(MCQ)
    • Often it presents with a pathological fracture
    • Typical radiological features (MCQ)
      • Eccentric well-defined radiolucent area.
      • Expansion of the overlying cortex.
      • Trabeculation within the substance of the tumour.
    • Treatment
      • curettage and bone grafting. (MCQ)
      • Recurrence occurs in 25 per cent cases
      • Some surgeons prefer to excise the lesion en bloc and fill the gap with bone grafts. (MCQ)