Nora’s lesion, a distinct radiological entity?
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
To describe the radiological findings of “Bizarre parosteal osteochondromatous proliferation”(BPOP)—otherwise known as Nora’s lesion, to describe the natural evolution of BPOP and to assess radiologically if BPOP is indeed part of a spectrum of reactive lesions including florid reactive periostitis and turret exostosis.
Four experienced musculoskeletal radiologists studied plain radiographs and other imaging documents of histologically-proven Nora’s lesions, looking for soft-tissue changes, periosteal reaction/calcification and calcified/ossified pseudotumours, and compared those findings with findings on pathology reviewed by a peer group of pathologists.
Twenty-four Nora’s lesions originating from a series of 200 consecutive, histologically-verified bone (pseudo)tumours of the hand, seen by the “Netherlands Committee on Bone Tumours” for review and second opinion.
Nora’s lesions have a recognised presentation on radiographs without specific MR characteristics. Natural evolution could be assessed retrospectively in four cases. Recurrent lesions were seen in seven cases and are difficult to differentiate from primary lesions.
Nora’s lesion, defined as a “well-marginated mass of heterotopic mineralization arising from the periosteal aspect of an intact cortex, without medullary changes” has a distinct radiological presentation and is part of a spectrum of reactive lesions which includes florid reactive periostitis and turret exostosis. As it has a distinct radiological appearance, differential diagnosis of malignant lesions such as osteosarcoma and chondrosarcoma should be clear. It does not require immediate biopsy unless the natural evolution is unspecific.
- Nora FE, Dahlin DC, Beabout JW. Bizarre parosteal osteochondromatous proliferations of hand and feet. Am J Surg Pathol 1983;7:245–250 CrossRef
- Torreggiani WC, Munk PL, Al-Ismail K, et al. MR imaging features of bizarre parosteal osteochondromatous proliferation of bone (Nora’s lesion). Eur J Radiol 2001;40:224–231 CrossRef
- Sundaram M, Wang L, Rotman M, Howard R, Saboeiro AP. Florid reactive periostitis and bizarre parosteal osteochondromatous proliferation: pre-biopsy imaging evolution, treatment and outcome. Skelet Radiol 2001;30:192–198 CrossRef
- Meneses MF, Unni KK, Swee RG. Bizarre parosteal osteochondromatous proliferation of bone (Nora’s lesion). Am J Surg Pathol 1993;17 7:691–697 CrossRef
- Bandiera S, Bacchini P, Bertoni F. Bizarre parosteal osteochondromatous proliferation of bone. Skelet Radiol 1998;27:154–156 CrossRef
- Cooper PN, Malcolm AJ. A bizarre parosteal osteochondromatous proliferation of the radius. Histopathology 1993;22:78–80 CrossRef
- Dahlin DC, Unni KK. Bone tumours: general aspects and data on 8542 cases. Springfield, IL: Charles C. Thomas; 1986
- Abramovici L, Steiner GC. Bizarre parosteal osteochondromatous proliferation of bone (Nora’s lesion) : a retrospective study of 12 cases, 2 arising in long bones. Human Pathol 2002;33:1205–1210 CrossRef
- Orui H, Ishikawa A, Tsuchiya T, Ogino T. Magnetic resonance imaging characteristics of bizarre parosteal osteochondromatous proliferation of the hand: A case report. J Hand Surg 2002;27A:1104–1108 CrossRef
- Dorfman HD, Czerniak B. Bone tumors. St. Louis, MO: Mosby; 1998
- Yuen M, Friedman L, Orr W, Cockshott WP. Proliferative periosteal processes of phalanges: a unitary hypothesis. Skelet Radiol 1992;21:301–303 CrossRef
- Rosenberg L. Chemical basis for histological use of Safranin O in the study of articular cartilage. J Bone Joint Surg 1971;A53:69–82
- Nora’s lesion, a distinct radiological entity?
Volume 35, Issue 7 , pp 497-502
- Cover Date
- Print ISSN
- Online ISSN
- Additional Links
- Florid reactive periostitis
- Bizarre parosteal osteochondromatous proliferation
- Nora’s lesion
- Turret exostosis
- Industry Sectors
- Author Affiliations
- 1. Department of Radiology and Pathology(•), Leiden University Medical Center, Albinusdreef 2, P.O. Box 9600, 2300, RC Leiden, The Netherlands