The Lodwick classification is a system for describing the margins of a lytic bone lesion (or lucent bone lesion). The terms used in the description suggest the level of concern for an aggressive, and possibly malignant, process.
type 1: geographic
- 1A: thin, sclerotic margin
- 1B: distinct, well-marginated border, but not sclerotic
- 1C: indistinct border
- type 2: moth-eaten
- type 3: permeative
The classification scheme is vaguely ordinal, with higher numbers representing more aggressive disease, but the terminology should be used more as a way to suggest a range of differential diagnoses than as an indication of malignancy (for instance, benign osteomyelitis could have a type 3 appearance).
Type 1A is usually indicative of a benign lesion with slow growth kinetics (e.g. unicameral bone cyst). Treated metastases may also show a sclerotic rim, however.
The differential for type 1B lesions contains malignant lesions.
In 2016 the "modified Lodwick-Madewell grading system" was proposed in an attempt to better reflect the risk of malignancy in each category 4 .
This new system has several differences in comparison to the old system. In this new modified classification system all grade I and II lesions are geographic, with IA including a sclerotic rim and IB without. Grade II lesions are no longer classified moth-eaten lesions but geographic ones with some areas of ill defined margins. Grade III now includes a grade IIIa with changes in the margin over time, grade IIIb with permeative and/or moth eaten edges and a grade IIIc for radiographically occult lesions.
Differentiation between types II and III in the original Lodwick classification system may be difficult, but often the distinction is not essential, and further imaging (CT or MRI) should be pursued.
Mixed types are possible in some scenarios (for instance transformation of a benign lesion into a malignant lesion).
In addition to the Lodwick classification, periosteal reaction may help characterize a bone lesion.
- 1. Lodwick GS, Wilson AJ, Farrell C et-al. Determining growth rates of focal lesions of bone from radiographs. Radiology. 1980;134 (3): 577-83. doi:10.1148/radiology.134.3.6928321 - Pubmed citation
- 2. Lodwick GS, Wilson AJ, Farrell C et-al. Estimating rate of growth in bone lesions: observer performance and error. Radiology. 1980;134 (3): 585-90. doi:10.1148/radiology.134.3.6986621 - Pubmed citation
- 3. Morrison WB, Sanders TG. Problem solving in musculoskeletal imaging. Mosby. ISBN:0323040349. Read it at Google Books - Find it at Amazon
- 4. Jamie T. Caracciolo, H. Thomas Temple, G. Douglas Letson, Mark J. Kransdorf. A Modified Lodwick-Madewell Grading System for the Evaluation of Lytic Bone Lesions. (2016) American Journal of Roentgenology. 207 (1): 150-6. doi:10.2214/AJR.15.14368 - Pubmed