Bone cysts

(1) Aneurysmal vs (2) Unicameral
Differentiate by: Site, Pathology, Sx, Radiology, Tx
Aneurysmal is bloody painful and hits mainly the legs. (why me? why anyone?)
Unicameral... camera filled with water -> gets broken.

Site:

1. femur, tibia
2. femur, humerus

Pathology

1. bloody contents
2. serous contents

Symptoms

1. painful
2. painless (unless pathologic fracture)

Radiology

1. expansile lesion, sclerotic rim
2. expansile lesion with intact cortex

Treatment

1. currettage
2. steroid injection, curretage

Aneurysmal Bone Cyst

1. Reactive lesion of bone: Rapidly growing expansile lesion
2. Common sites: femur, tibia, spine; may involve adjacent vertebrae
3. Symptoms: Pain and swelling
4. Radiology: Expansion, Lytic destruction, –Thin, sclerotic rim
5. Treatment: curettage, bone grafting, excision

---

Unicameral Bone Cyst

1. Fluid filled lesion
2. Cause unknown
3. Common sites: proximal humerus & femur
4. Symptoms: painless (presents with pathologic fracture after a minor injury)
5. Radiology:
   • Solitary, central location
   • Cortical expansion and thinning
   • Does not interrupt physis
6. Treatment: injection with methylprednisolone or curettage