Common Tumors and Tumor-like Lesions of the Shoulder.

Shoulder lesions range from tumor-like lesions such as simple bone cysts to aggressive high-grade sarcomas. The clinical presentation is often nonspecific with shoulder pain as the primary complaint, which may lead to a delayed or missed diagnosis. Delayed diagnosis or a poorly planned biopsy of a malignant shoulder lesion can have a detrimental effect on the patient's prognosis and treatment options. Because the initial patient assessment is crucial for successful treatment, knowledge of the key features of common shoulder tumors and tumor-like conditions can help determine the diagnosis and treatment plan. This article reviews the key features and treatment options of the more commonly encountered benign and malignant shoulder bone and soft-tissue tumors and tumor-like conditions.

Florid reactive periostitis ossificans of the humerus: Case report and differential diagnosis of periosteal lesions of long bones.

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.

Prosthetic implant associated sarcomas: a case report emphasizing surface evaluation and spectroscopic trace metal analysis.

Advances with implantation of synthetic biomaterials in the setting of orthopedic surgery have clearly resulted in improvements in patient outcomes. However, all implants have been shown to have associated risks. For example, ionic and particulate debris from implants have been shown to engage in biological interactions with the native tissue, and have been associated with a wide range of metabolic, bacteriologic, immunologic, and oncogenic effects. The propensity of synthetic biomaterials to undergo degradation, producing an inflammatory reaction or other sequelae, has been well recognized. The use of porous implants, which allow for a greater interface area between native tissue and the prosthesis, may magnify the interaction between biologically active tissue and synthetic devices in some situations, giving rise to new and intriguing issues concerning biocorrosion and biocompatibility. In this article, we report the case of a high-grade conventional osteosarcoma occurring at the site of a modular porous-surfaced titanium and cobalt alloy total hip prosthesis 3 years after device implantation. Detailed spectroscopic trace metal analysis was performed and elevated levels of both vanadium and chromium, but not aluminum, nickel, or titanium were identified in the tumor.