Radiology Case Reports

Volume 8, Issue 3, 2013

Intramedullary : An incidental sclerotic lesion in a trauma patient

Bethany Casagranda, DO; Matthew T. Heller, MD; and Joanna Costello, MD

Intramedullary osteosclerosis, a rare entity, is usually diagnosed after the exclusion of more sinister eti- ologies. It typically affects the lower extremity and is more common in females. While the lesion may be discovered incidentally during imaging, presenting symptoms may include pain in the affected that is exacerbated with physical activity. Laboratory values are normal, and the lesion is not associated with familial skeletal dysplasias. Common imaging findings include a mono-ostotic or polyostotic sclerotic le- sion that lacks a periosteal reaction, soft-tissue component, and nidus. We present a case of intramedul- lary osteosclerosis that was incidentally discovered in a trauma patient.

Case report A 22-year-old female patient presented to the Emergency Department following a motor vehicle crash in which she was a restrained driver. Her vital signs were normal, and she remained hemodynamically stable during her assess- ment in the Emergency Department. No laboratory ab- normalities were reported. She reported no past medical history and denied knowledge of any familial diseases. On review of systems, she described mild, intermittent pain in her left hip during periods of extended activity. The pa- tient’s chief presenting complaints consisted of pain in the right shoulder and the right side of the pelvis. Physical examination revealed tenderness in the right shoulder and hip, but was otherwise normal. Radiographs of the chest, right arm/shoulder, and pelvis (Fig. 1) were also obtained. The patient underwent contrast-enhanced CT examinations of the chest, abdomen, and pelvis (Fig. 2). No acute abnormalities were identified on any imaging

Citation: Casagranda B, Heller MT, Costello J. Intramedullary osteosclerosis: An Figure 1. 22-year-old woman with intramedullary osteosclerosis. incidental sclerotic lesion in a trauma patient. Radiology Case Reports. (Online) Supine pelvic radiograph shows a sclerotic lesion in the left femoral 2013;8:878. head and neck (arrows). There is artifact from the underlying Copyright: © 2013 The Authors. This is an open-access article distributed under the trauma board. terms of the Creative Commons Attribution-NonCommercial-NoDerivs 2.5 License, which permits reproduction and distribution, provided the original work is properly cited. Commercial use and derivative works are not permitted. examinations. However, a solitary sclerotic lesion was iden- Dr. Casagranda is in the Department of Radiology at Allegheny General Hospital/ Temple University School of Medicine, and Drs. Heller and Costello are both in the tified in the left femur involving the head, neck, and proxi- Department of Radiology at the University of Pittsburgh Medical Center, all in Pitts- mal shaft. The sclerosis involved the medullary space and burgh PA. Contact. Dr. Heller at [email protected]. did not result in any cortical sclerosis or thickening. No Competing Interests: The authors have declared that no competing interests exist. periosteal reaction or soft-tissue abnormality was identified. DOI: 10.2484/rcr.v8i4.878

RCR Radiology Case Reports | radiology.casereports.net! 1! 2013 | Volume 8 | Issue 4 Intramedullary osteosclerosis: An incidental sclerotic lesion in a trauma patient

Discussion Intramedullary osteosclerosis is associated with abnormal bone formation in the medullary cavity of long and was first described as a distinct entity in 1988 (1). It typi- cally affects the lower extremities and is most commonly found in the ; it occurs in adults and shows a female predilection. Intramedullary osteosclerosis is not associated with skeletal syndromes or familial diseases. While some cases may be discovered incidentally, most patients endorse a history of chronic, intermittent leg pain that is exacer- bated by periods of increased physical activity (1). Imaging plays a key role in diagnosis, while correlation to the pa- tient’s demographics, medical history, and family history facilitates differentiation from other osseous lesions. The imaging findings of intramedullary osteosclerosis consist of homogeneous sclerosis that primarily affects the medullary cavity. In most cases, the cortex remains normal or is only minimally thickened. There is no associated bone deformity, and the periosteum is also unaffected. While there may be mild soft-tissue swelling adjacent to the af- fected bone, there is no discreet soft-tissue lesion. Intrame- dullary osteosclerosis may be bilateral and polyostotic; in these cases, the lesions are asymmetric. Intramedullary sclerotic lesions often have nonspecific imaging findings and may be due to hereditary skeletal dysplasia, acquired skeletal dysplasia, malignancy, benign neoplasm, infection, or injury (2-5). However, specific im- aging and clinical findings may allow differentiation of intramedullary osteosclerosis from several other conditions. Intramedullary osteosclerosis lacks the periosteal reaction that is commonly caused by malignancies such as osteosar- coma, lymphoma, and osteoblastic metastases (6). Osetoid osteoma is associated with a radiolucent nidus, whereas intramedullary osteosclerosis results in homogeneous scle- rosis (7). Chronic should be considered only when the patient’s medical history, clinical, and laboratory parameters are appropriate (8). A healing is often a consideration, since the presentation and imaging findings are often similar to intramedullary osteosclerosis; however, the absence of a discreet cortical fracture line usually allows differentiation (9). Several metabolic and Figure 2. 22-year-old woman with intramedullary osteosclerosis. endocrine disorders, such as and Axial CT of the pelvis demonstrates the sclerotic lesion (arrows) pseudohypoparathyroidism, can usually be differentiated affecting the left femoral (a) head, (b) neck, and (c) proximal shaft. from intramedullary osteosclerosis by laboratory abnor- Note the lack of periosteal reaction, fracture line, and soft-tissue malities and more diffuse osteosclerosis. Of the numerous abnormality. sclerosing bone dysplasias, only Camurati-Engelmann dis- ease and Ribbing disease have imaging findings that closely The diagnostic considerations for the sclerotic femoral parallel those of intramedullary osteosclerosis; however, lesion were broad and included sclerosing bone dysplasias, since both of these dysplasias are genetic diseases, do not overlap syndromes simulating bone dysplasias (osteoblastic preferentially affect women,and manifest earlier, they can neoplasms, Paget’s disease, myelofibrosis, Erdheim-Chester typically be differentiated from intramedullary disease, sickle cell disease), severe stress response/healed osteosclerosis (10, 11). fracture, and osteoid osteoma. Due to the patient’s demo- graphics and lack of past medical and familial history, a References diagnosis of intramedullary osteosclerosis was made. The patient was discharged without any specific followup in- 1. Abdul-Karim FW, Carter JR, Makley JT, Morrison structions. Followup radiography performed approximately SC, Helper SD, Joyce MJ, Linke TF. Intramedullary one year later showed that the lesion has remained stable. osteosclerosis. A report of the clinicopathologic fea-

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tures of five cases. Orthopedics. 1988 Dec;11:1667-75. 7. Swee RG, McLeod RA, Beabout JW. Osteoid osteoma. [PubMed] Detection, diagnosis, and localization. Radiology. 1979 2. Ihde LL, Forrester DM, Gottsegen CJ, Masih S, Patel Jan;130:117-23. [PubMed] DB, Vachon LA, White EA, Matcuk GR, Jr. Sclerosing 8. Collert S, Isacson J. Chronic sclerosing osteomyelitis bone dysplasias: review and differentiation from other (Garre). Clin Orthop Relat Res. 1982 Apr;136-40. [Pub- causes of osteosclerosis. Radiographics. 2011 Med] Nov-Dec;31:1865-82. [PubMed] 9. Anderson MW, Greenspan A. Stress fractures. Radiol- 3. Jacobson HG. Dense bone--too much bone: radiologi- ogy. 1996 Apr;199:1-12. [PubMed] cal considerations and differential diagnosis. Part II. 10. Kaftori JK, Kleinhaus U, Naveh Y. Progressive dia- Skeletal Radiol. 1985 13:97-113. [PubMed] physeal dysplasia (Camurati-Engelmann): radiographic 4. Greenspan A. Sclerosing bone dysplasias--a target-site follow-up and CT findings. Radiology. 1987 approach. Skeletal Radiol. 1991 20:561-83. [PubMed] Sep;164:777-82. [PubMed] 5. Chanchairujira K, Chung CB, Lai YM, Haghighi P, 11. Shier CK, Krasicky GA, Ellis BI, Kottamasu SR. Rib- Resnick D. Intramedullary osteosclerosis: imaging fea- bing's disease: radiographic-scintigraphic correlation tures in nine patients. Radiology. 2001 Jul;220:225-30. and comparative analysis with Engelmann's disease. J [PubMed] Nucl Med. 1987 Feb;28:244-8. [PubMed] 6. Balkissoon AR, Hayes CW. Case 14: intramedullary osteosclerosis. Radiology. 1999 Sep;212:708-10. [Pub- Med]

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