Case Report
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Aug 18, 2015; 6(7): 559-563
Published online Aug 18, 2015. doi: 10.5312/wjo.v6.i7.559
Florid reactive periostitis ossificans of the humerus: Case report and differential diagnosis of periosteal lesions of long bones
Abha Soni, Alec Weil, Shi Wei, Kenneth A Jaffe, Gene P Siegal
Abha Soni, Shi Wei, Gene P Siegal, R.W. Mowry, Endowed Professor of Pathology, the Division of Anatomic Pathology, University of Alabama at Birmingham, Birmingham, AL 35249, United States
Alec Weil, Kenneth A Jaffe, Alabama Orthopaedic Center, Birmingham, AL 35209, United States
Author contributions: All authors contributed to the acquisition of data, writing, and revision of this manuscript.
Supported by The University of Alabama at Birmingham, Alabama and The Orthopaedic Center, Birmingham, AL, United States.
Institutional review board statement: This case report was exempt from the Institutional Review Board standards at The University of Alabama at Birmingham.
Informed consent statement: The patient involved in this study gave her written informed consent authorizing use and disclosure of her protected health information.
Conflict-of-interest statement: All the authors have no conflicts of interest to declare.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Gene P Siegal, MD, PhD, R.W. Mowry, Endowed Professor of Pathology, the Division of Anatomic Pathology, University of Alabama at Birmingham, HSB149K, 618 18th Street South, Birmingham, AL 35249, United States. gsiegal@uab.edu
Telephone: +1-205-9346608 Fax: +1-205-9757284
Received: February 28, 2015
Peer-review started: March 2, 2015
First decision: May 14, 2015
Revised: June 6, 2015
Accepted: June 18, 2015
Article in press: June 19, 2015
Published online: August 18, 2015
Processing time: 172 Days and 14.2 Hours
Abstract

A case of florid reactive periostitis ossificans (RPO) arising in a long bone is presented. This is a rare bone proliferation with a pronounced periosteal reaction. Less than 100 cases have been described in the literature with far fewer outside the bones of the hand, feet, fingers, and toes. Although the etiology is unknown, a relationship to preceding trauma is suggested. The imaging and histologic features show an overlap with other bone lesions including bizarre parosteal osteochondromatous proliferation, subungual exostosis, and malignant surface tumors of bone and cartilage which include, periosteal and parosteal osteosarcoma. It is important to recognize the clinical presentation and diagnostic features of RPO as a benign entity so that it is not mistaken for a more aggressive neoplasm. We present a case of a right distal humeral lesion that on histopathological review revealed florid RPO. This diagnosis was not suspected on imaging studies, but was made on open biopsy of the mass. The patient remains disease free, years postoperatively. In addition to presenting this unique case report, we review the pertinent literature, and offer a differential diagnosis and treatment strategy for its management.

Keywords: Bizarre parosteal osteochondromatous proliferation (Nora’s lesion); Reactive tumor-like lesions of long bones; Florid reactive periostitis ossificans; Periosteal and parosteal osteosarcomas

Core tip: Florid reactive periostitis ossificans (RPO) is a rare benign entity that is classically localized to the phalanges of the distal extremities. This lesion is often clinico-radiologically and histologically confused for malignant entities, like osteosarcoma and chondrosarcoma. We report a rare presentation of this lesion arising from the posterior aspect of the right elbow in a 38-year-old woman, diagnosed on biopsy. Recognizing the key similarities and differences between florid RPO, and other similar appearing disorders discussed in this paper, can prevent the pitfall of misdiagnosis and unnecessary aggressive surgery.