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.

Proximal tibial extra-axial chordoma masquerading as renal cell carcinoma metastasis.

Chordomas are rare, locally aggressive notochordal tumors, which most frequently occur in the neuraxis. We describe the case of a 74-year-old male with a history of renal cell carcinoma, who presented with a slowly enlarging mass in his left leg. While the clinical history and imaging suggested metastatic renal cell carcinoma, immunohistochemical staining with brachyury ultimately made the diagnosis of extra-axial chordoma. At 74 years of age, our patient is the oldest ever reported with bony extra-axial chordoma objectively confirmed by brachyury staining. A detailed case discussion and a review of the available literature on this rare clinicopathologic entity are provided.

Tenosynovial chondromatosis of the flexor hallucis longus in a 17-year-old girl.

Tenosynovial chondromatosis is a benign chondrogenic metaplasia of extra-articular synovial tissue. The most common locations for tenosynovial chondromatosis to develop are the hands and feet. The condition has rarely been reported in children. We present a case of tenosynovial chondromatosis of the flexor hallucis longus in a 17-year-old girl. The presentation was unusual not only due to the location and young age of the patient but also the absence of any palpable mass on physical exam and complete lack of calcification of the cartilage bodies. Initial diagnosis was made by MRI. The patient underwent tenosynovectomy with an excellent postoperative recovery at 6-month follow-up. Histopathology confirmed the diagnosis of tenosynovial chondromatosis.

Epithelioid hemangioma occurring in the radial styloid of a 17-year-old boy-an unusual presentation of an uncommon neoplasm.

Presented is a case of epithelioid hemangioma (EH) of bone occurring in the radial styloid of a 17-year-old boy. EH is a benign vascular tumor whose name and classification have changed over the years, adding potential confusion to an already existing diagnostic challenge. Overlapping imaging and histopathologic features with malignant vascular neoplasms and occasional aggressive clinical features have resulted in misdiagnoses and inappropriate treatment. The goal of this case report is to raise awareness of EH and related vascular neoplasms.

Radiographic outcomes of volar locked plating for distal radius fractures.

PURPOSE: To assess the ability of volar locked plating to achieve and maintain normal radiographic parameters for articular stepoff, volar tilt, radial inclination, ulnar variance, and radial height in distal radius fractures. METHODS: We performed a retrospective review of 185 distal radius fractures that underwent volar locked plating with a single plate design over a 5-year period. We reviewed radiographs and recorded measurements for volar tilt, radial inclination, ulnar variance, radial height, and articular stepoff. We used logistic regression to determine the association between return to radiographic standard norms and fracture type. RESULTS: At the first and final postoperative follow-up visits, we observed articular congruence less than 2 mm in 92% of fractures at both times. Normal volar tilt (11°) was restored in 46% at the first follow-up and 48% at the final one. Radial inclination (22°) was achieved in 44% at the first follow-up and 43% at the final one, and ulnar variance (01 ± 2 mm) was achieved in 53% at the first follow-up and 53% at the final one. In addition, radial height (14 ± 1mm) was restored in 14% at the first follow-up and 12% at the final one. More complex, intra-articular fractures (AO class B and C and Frykman types 3, 4, 7, and 8) were less likely to be restored to normal radiographic parameters. However, because of the small sample size for some fracture types, it was difficult to discover significant associations between fracture type and radiographic outcome. CONCLUSIONS: Volar locked plating for distal radius fractures achieved articular stepoff less than 2 mm in most fractures but only restored and maintained normal radiographic measurements for volar tilt, radial inclination, and ulnar variance in 50% of fractures. The ability of volar locked plating to restore and maintain ulnar variance and volar tilt decreased with more complex intra-articular fracture types. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

SARL: shoulder acronyms. A review of the literature.

Acronyms are words formed by taking the first initial or other parts of words from a compound term. They are designed to help communicate ideas efficiently. In the literature pertaining to shoulder surgery, a variety of acronyms have been offered for normal anatomic states, physical examination findings, pathologic conditions, surgical techniques, and outcome instruments, with new acronyms offered each year. The purpose of this article is to review and clearly define acronyms used by shoulder specialists.

Minute amounts of intraarticular gas mimicking torn discoid lateral menisci.

Presented are two cases of minute amounts of vacuum phenomena within the central portion of the lateral compartments of two knee joints, mimicking torn discoid lateral menisci. In each case, only the gradient echo images were able to correctly characterize the minute quantities of intraarticular gas by demonstrating "blooming" magnetic susceptibility artifact. The signal characteristics of the intraarticular gas were identical to those of fibrocartilage on all of the remaining routine, fast spin echo, "sports protocol" magnetic resonance imaging sequences.

The "rising bubble" sign: a new aid in the diagnosis of unicameral bone cysts.

The observation of a bubble of gas at the most non-dependent margin of a lytic bone lesion which has sustained a pathologic fracture implies that the lesion is hollow and can assist the radiologist in making the diagnosis of a unicameral bone cyst. The imaging studies of two patients who sustained pathologic fractures through unicameral bone cysts and exhibited the "rising bubble" sign are shown. The sign's basis, proper utilization, and potential pitfalls are discussed.

Transarticular spread of Ewing sarcoma mimicking septic arthritis.

Transarticular spread of tumor is rare; it has only been reported in the sacroiliac joint, intervertebral disk spaces, and facet joints. The anatomic and kinetic characteristics of the sacroiliac joint, as well as the changes the joint undergoes during a lifetime, make it particularly vulnerable to transarticular tumor invasion. Although extremely rare, Ewing sarcoma can extend through the sacroiliac joint and be virtually indistinguishable radiologically from septic arthritis. Furthermore, the clinical presentation of a child with Ewing sarcoma can be similar to that of a child with osteomyelitis. Laboratory values are quite nonspecific and are not always helpful in differentiating between the entities. Therefore, the possibility of sacroiliac joint transarticular Ewing sarcoma should be considered in a child presenting with hip pain, despite clinical, radiological and laboratory findings suggesting an infectious process.

Inadvertent intraosseous gadolinium injection during pediatric shoulder MR arthrography.

A variety of problems can arise while performing MR arthrography of the shoulder. These have been well documented in the literature and range from improper patient selection to errors in technique or in the choice of imaging sequences. We present a rare case of inadvertent, painless intraosseous injection of dilute gadolinium into the proximal humeral epiphysis of a 13-year-old male athlete. The clinical relevance is discussed and technical recommendations are offered.