Metaphyseal Enchondroma
Arise from the metaphyseal cortex of long bones
- most common in the proximal humerus
Difficult to DDx from Chondrosarcoma
Masses of cartilage nestling in a shallow crater in the periphery of the cortex
Don't ossify
- remain as immature cartilage
Non Ossifying Fibroma
A hamartomatous defect in the metaphyseal cortex of skeletally-immature adolescents
Fibrous cortical defect
- < 2cm in diameter
Non ossifying fibromas
- > 2cm
Benign lesion with a wide spectrum of behavior characterized by stromal cells and giant cells
Common
- 20% of benign tumours
More common females
- F:M = 1.5:1
- most tumours M>F
Usually patient in 20's
- usually after skeletal maturity
- 3% < epiphyseal closure
Langerhan's Cell Histiocytosis
- non-neoplastic disorder
- characterised by infiltration by histiocytic cells (Monocyte / macrophage lineage)
Group of granulomatous inflammatory processes of unknown aetiology
- involve the reticuloendothelial component of the bone marrow, parenchymal organs, and skin
E - H - L
Benign neoplasm of cartilaginous origin composed primarily of myxoid cartilage
Previously thought to be Chondrosarcoma
Very rare tumour
- young adults 10-30
- M:F 2:1
Common upper tibia
- metaphysis of long bones
- lower limb predilection
Tenderness
Rare cartilage tumour
1% of bone tumours / rare
- typically in adolescents
Usually benign
- but aggressive / frankly malignant behaviour reported
- locally aggressive
- can have pulmonary metastasis
Rare low-grade malignant tumour
- cell of origin unknown
Usually second or third decade of life
90% diaphysis of tibia
Mandible
Most common anterior cortex of tibia
Expansile pseudotumor of reactive hemorrhagic tissue arising in bone
- characterised by blood filled spaces separated by fibrous tissue
Primary 50%
- arise de novo
Secondary 50%
- in association with other tumours
- probably secondary to haemorrhage into 1° tumour
- GCT / chondroblastoma / osteoblastoma / osteosarcoma
Stage the infection, the host & the management
1. Stage host / maximise healing potential
2. Stage infection / MCS / sensitivities
3. Debride all infected bone and ST
4. Stabilise skeleton
5. Eliminate dead space
6. Soft tissue coverage
Definition
Infection of bone 2° blood-borne bacteria
Most common children
- peak 10 years
True haematogenous OM rare in adults
- usually involves spine
M: F 2:1
Most common femur & tibia