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Differential Diagnosis of Musculoskeletal Disorders

Bubbly Bone Lesion!!navigator!!

mnemonic: FOGMACHINES

  • Fibrous dysplasia, Fibrous cortical defect
  • Osteoblastoma
  • Giant cell tumor
  • Myeloma (plasmacytoma), Metastases from kidney, thyroid, breast
  • Aneurysmal bone cyst / Angioma
  • Chondromyxoid fibroma, Chondroblastoma
  • Hyperparathyroid brown tumor, Hemangioma, Hemophilia, Histiocytosis X
  • Infection (Brodie abscess, Echinococcus, coccidioidomycosis)
  • Nonossifying fibroma
  • Eosinophilic granuloma, Enchondroma, Epithelial inclusion cyst
  • Solitary bone cyst

mnemonic: FEGNOMASHIC

  • Fibrous dysplasia
  • Enchondroma / Eosinophilic granuloma
  • Giant cell tumor
  • Nonossifying fibroma
  • Osteoblastoma
  • Metastasis, Myeloma
  • Aneurysmal bone cyst
  • Simple bone cyst
  • Hyperparathyroidism
  • Infection
  • Chondroblastoma, Chondromyxoid fibroma

Infectious Bubbly Lesion

  1. Brodie abscess (Staph. aureus)
  2. Coccidioidomycosis
  3. Echinococcus
  4. Atypical mycobacterium
  5. Cystic tuberculosis

Blowout Lesion

  1. METASTASES
    Carcinoma of thyroid, kidney, breast
  2. PRIMARY BONE TUMOR
    1. Fibrosarcoma
    2. Multiple myeloma (sometimes)
    3. Aneurysmal bone cyst
    4. Hemophilic pseudotumor

Nonexpansile Well-demarcated Bone Defect!!navigator!!

Unilocular Well-demarcated Bone Defect

  1. Fibrous cortical defect
  2. Nonossifying fibroma
  3. Simple unicameral bone cyst
  4. Giant cell tumor
  5. Brown tumor of HPT
  6. Eosinophilic granuloma
  7. Enchondroma
  8. Epidermoid inclusion cyst
  9. Posttraumatic / degenerative cyst
  10. Pseudotumor of hemophilia
  11. Intraosseous ganglion
  12. Histiocytoma
  13. Arthritic lesion
  14. Endosteal pigmented villonodular synovitis
  15. Fibrous dysplasia
  16. Infectious lesion

Multilocular Well-demarcated Bone Defect

  1. Aneurysmal bone cyst
  2. Giant cell tumor
  3. Fibrous dysplasia
  4. Simple bone cyst

Expansile Unilocular Well-demarcated Osteolysis!!navigator!!

  1. Simple unicameral bone cyst
  2. Enchondroma
  3. Aneurysmal bone cyst
  4. Juxtacortical chondroma
  5. Nonossifying fibroma
  6. Eosinophilic granuloma
  7. Brown tumor of HPT

Poorly Demarcated Osteolytic Lesion!!navigator!!

Osteolytic Lesion without Periosteal Reaction

  1. NONEXPANSILE
    1. Metastases from any primary neoplasm
    2. Multiple myeloma
    3. Hemangioma
  2. EXPANSILE
    1. Chondrosarcoma
    2. Giant cell tumor
    3. Metastasis from kidney / thyroid

Osteolytic Lesion with Periosteal Reaction

  1. Osteomyelitis
  2. Ewing sarcoma
  3. Osteosarcoma

Mixed Sclerotic and Lytic Lesion!!navigator!!

Mixed Bone Lesion without Sequestrum

  1. Osteomyelitis
  2. Tuberculosis
  3. Ewing sarcoma
  4. Metastasis
  5. Osteosarcoma

Mixed Bone Lesion with Button Sequestrum

  • bone opacity surrounded by a well-defined lucent area

common:

  1. Osteomyelitis
  2. Eosinophilic granuloma
  3. Fibrosarcoma, desmoplastic fibroma, MFH
  4. Lymphoma

uncommon:

  • partially calcified intraosseous lipoma, tuberculous osteitis, radiation necrosis, metastatic carcinoma, fibrous dysplasia, dermoid & epidermoid cyst, hemangioma, meningioma

Trabeculated Bone Lesion!!navigator!!

1. Giant cell tumor:delicate thin trabeculae
2. Chondromyxoid fibroma:coarse thick trabeculae
3. Nonossifying fibroma:lobulated
4. Aneurysmal bone cyst:delicate, horizontally oriented trabeculae
5. Hemangioma:striated radiating trabeculae

Lytic Bone Lesion Surrounded by Marked Sclerosis!!navigator!!

mnemonic: BOOST

  • Brodie abscess
  • Osteoblastoma
  • Osteoid osteoma
  • Stress fracture
  • Tuberculosis

Multiple Lytic Lesions!!navigator!!

mnemonic: FEEMHI

  • Fibrous dysplasia
  • Enchondromas
  • Eosinophilic granuloma
  • Metastases, Multiple myeloma
  • Hyperparathyroidism (brown tumors), Hemangiomas
  • Infection

Multiple Lytic Lesions in Child

  1. Histiocytosis X
  2. Metastatic neuroblastoma / leukemia
  3. Fibrous dysplasia
  4. Enchondromatosis
  5. Rare: cystic angiomatosis, multifocal osteomyelitis

Lytic Bone Lesion in Patient <30 Years of Age!!navigator!!

mnemonic: CAINES

  • Chondroblastoma
  • Aneurysmal bone cyst
  • Infection
  • Nonossifying fibroma
  • Eosinophilic granuloma
  • Solitary bone cyst

Lytic Bone Lesion on Both Sides of Joint!!navigator!!

mnemonic: SAC

  • Synovioma
  • Angioma
  • Chondroid lesion

Multiple Bone Lesions with Soft-tissue Tumor!!navigator!!

  1. Neurofibromatosis & fibroxanthomas
  2. Maffucci syndrome = enchondromatosis & hemangioma
  3. Mazabraud syndrome = fibrous dysplasia & myxoma
  4. Metastases
    1. Multiple myeloma
    2. Malignant melanoma
    3. Lymphoma

Osteoblastic Bone Lesion!!navigator!!

  1. BENIGN
    1. Bone island
    2. Osteoma
    3. Osteoid osteoma
  2. MALIGNANT
    1. Osteosarcoma
    2. Parosteal sarcoma

Widespread Osteosclerotic Lesions!!navigator!!

  1. Metastases: prostate, breast, lung, bladder, pancreas, stomach, colon, carcinoid, brain
  2. Paget disease
  3. Sarcoma
  4. Myelofibrosis
  5. Mastocytosis

Outline