Modified Lodwick-Madewell Classification

Concepts (update from previous edition)

Integrates static margin + dynamic changes + “invisible”/occult category so temporal evolution and radiographically occult disease matter.

Use this only to categorise lesion margin/aggressiveness. Patient age and lesion location are still KINGS for differential diagnosis.

Type	Description	Possible entities	Classic lesions
1A	Well-defined, geographic, sclerotic rim	Almost always benign lesions	NOF, SBC, Enchondroma
1B	Well-defined, geographic, sharp margin, no sclerotic rim	Usually benign but can be locally aggresive	GCT, Chondroblastoma
2	Geographic, ill-defined margin (partial/circumferential)	Worrisome for low-grade malignancy or active infection/inflammation	LCH, Low-grade Chondrosarcoma
3A	Any lesion that shows newly ill-defined margins or progressive endosteal scalloping	Dynamic process, increasing aggression	Secondary chondrosarcoma arising from enchondroma
3B	Moth-eaten/permeative	Highly aggressive: Small round blue cell tumours, infection	Ewing sarcoma, Lymphoma, Osteosarcoma, Osteomyelitis
3C	Radiographically occult	Seen only on MRI/CT; can be malignant	Early myeloma, Leukaemia, Early mets

≤2 = Geographic borders that
- 1 = well-defined
  - 1A = with sclerotic rim
  - 1B = without sclerotic rim
- 2 = ill-defined
Key changes from original → modified:
- IC → 2 (geographic, ill-defined)
- II, III → 3B (moth-eaten/permeative)
- add 3A, 3C (new concepts)
Always compare with old images—look for margin change or endosteal scalloping.
- Change over time (3A): Key red flag for malignancy, even if original margin was geographic.
3C (occult): Remember that radiograph-negative does NOT mean benign → Flag for possible marrow infiltrative disease (e.g., myeloma, metastasis).