For the past 15 years, high-resolution ultrasonography (US) is being routinely and increasingly used for initial evaluation and treatment follow-up of rheumatologic diseases. This imaging technique is performed by using high-frequency linear transducers and has proved to be a powerful diagnostic tool in evaluation of articular erosions, simple and complex joint and bursal effusions, tendon sheath effusions, and synovitis, with results comparable to those of magnetic resonance imaging, excluding detection of bone marrow edema. Crystal deposition diseases including gouty arthropathy and calcium pyrophosphate deposition disease (CPPD) have characteristic appearances at US, enabling differentiation between these two diseases and from inflammatory arthropathies. Enthesopathy, which frequently accompanies psoriatic and reactive arthritis, also has a characteristic appearance at high-resolution US, distinguishing these two entities from other inflammatory and metabolic arthropathies. The presence of Doppler signal in examined joints, bursae, and tendon sheaths indicates active synovitis. Microbubble echo contrast agents augment detection of tissue vascularity and may act in the future as a drug delivery vehicle. Frequently, joint, tendon sheath, and bursal fluid aspirations and therapeutic injections are performed under US guidance. The authors describe the high-resolution US technique including gray-scale, color or power Doppler, and contrast agent-enhanced US that is used in evaluation of rheumatologic diseases of the wrist and hand and the ankle and foot in their routine clinical practice. This article demonstrates imaging findings of normal joints, rheumatoid arthritis, gouty arthritis, CPPD, psoriatic and reactive arthritis, and osteoarthritis.

Perilunate dislocations, perilunate fracture-dislocations (PLFDs), and lunate dislocations are high-energy wrist injuries that can and should be recognized on radio-graphs. These injuries are a result of important sequential osseous and ligamentous injuries or failures. Prompt and accurate radiographic diagnosis aids in the management of patients with perilunate dislocations, PLFDs, and lunate dislocations while assisting orthopedic surgeons with subsequent surgical planning. CT may better show the extent of the injury and help in treatment planning particularly in cases of delayed treatment or chronic perilunate dislocation. A CT examination with coronal, sagittal, and 3D reformatted images is ordered at our institution in cases in which the extent of the carpal injuries is poorly shown on radiographic examination.

Primary osteoarthritis (OA) involving the thumb carpometacarpal (CMC) joint is a common and frequently debilitating disease. Clinical examination and radiographs are usually sufficient for diagnosis; however, familiarity with the cross-sectional anatomy is useful for diagnosis of this condition. The most widely used classification system for the radiographic staging of thumb carpometacarpal joint OA was first presented by Eaton and Littler, ranging from mild (stages I and II) to severe (stage IV) disease. If conservative treatment fails, surgical treatment is considered. A variety of surgical techniques have been developed and implemented for the management of this pervasive and disabling condition. The purpose of this article is to review the anatomy of the basal joints of the thumb, pathophysiology, preoperative imaging, and various surgical techniques that are utilized in the treatment of OA of the basal joints of the thumb with emphasis on normal postoperative radiographic findings and possible postoperative complications.

ABSTRACT. We present an 80-year-old man with multiple medical problems, and acute abdominal pain with feculent emesis. An unenhanced CT examination of the abdomen and pelvis demonstrated jejunal diverticulitis and findings of high-grade small bowel obstruction caused by a large enterolith. Enterolith ileus has rarely been reported in the radiology literature. This phenomenon has occasionally been reported in the surgical and gastroenterology literature. We highlight the CT findings associated with enterolith ileus in the setting of jejunal diverticulitis, to alert radiologists to this unusual diagnosis. Case reportWe present an 80-year-old man with a medical history of hypertension, diabetes, left below-the-knee amputation for arterial disease, coronary arterial stent placement, myocardial infarction, Parkinson's dementia and splenectomy. The patient presented with a 1 day history of sharp, non-radiating left lower quadrant abdominal pain and feculent emesis. The patient was afebrile on presentation. Laboratory values were notable for a leukocytosis of 27 000 and acute renal failure.An unenhanced CT examination of the abdomen and pelvis was performed to evaluate the patient's abdominal pain. The study demonstrated a large-mouth jejunal diverticulum measuring 4.1 cm by 3.9 cm (Figure 1a,b,d,e). There was inflammation and oedema of the mesentery. The findings were diagnostic of jejunal diverticulitis. A second, although not inflamed, jejunal diverticulum was noted proximally (Figure 1c). Additionally, there was a 2.9 cm by 2.1 cm lamellated and partially-calcified enterolith (Figure 2a-d). The enterolith was not located within the above-mentioned inflamed jejunal diverticulum; however, it was noted more distally within the mid-small bowel lumen causing a high-grade small bowel obstruction with a transition point at the enterolith. Collapsed small bowel loops were noted distally. CT examination from 7 years earlier showed the jejunal diverticula in retrospect although they were smaller and did not contain any enteroliths (not shown). The CT findings were then prospectively reviewed with the attending surgeon.A nasogastric tube was then placed, and approximately 1.5 l of feculent material was removed. The patient underwent laparoscopic abdominal surgery which was subsequently converted to an exploratory laparotomy after finding adherent loops of small bowel, scarring and adhesions secondary to the patient's remote splenectomy. After running the small bowel proximal to the transition point of obstruction, an enterolith was palpated and was milked intraluminally to a proximal loop of jejunum, which was also noted to have a gross perforation at the inflamed jejunal diverticular site. A 38 cm segment of small bowel was resected. Pathological evaluation of the resected small bowel demonstrated chronic diverticular disease, an ulcerated/perforated diverticulum, mesenteric microabscesses and a 3 cm enterolith. The patient was post-operatively managed in the surgical intensive care unit secondary to intra-operative hypoten...

F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) has been shown to be useful in the evaluation of many tumors due to its high sensitivity and specificity. However, false-positive interpretations may occur from benign subcutaneous and cutaneous etiologies. At our institution we have encountered FDG-PET scans which demonstrated a variety of cutaneous and subcutaneous lesions including stomas, hernias, rhinophyma, dose infiltrations, physiologic muscle uptake, and tophaceous gout. Additionally, malignant cutaneous and subcutaneous malignant lesions may also demonstrate substantial F-18 FDG uptake on PET scans, including lymphoma, skin metastases, and melanoma. The purpose of this atlas article is to demonstrate and review key features of various cutaneous and subcutaneous lesions, both benign and malignant, which can result in hypermetabolism on FDG-PET or PET-CT scans.

Hand injuries are common, accounting for up to 20% of emergency department visits nationwide. An understanding of the complex and detailed anatomical relationships of small joints facilitates the accurate diagnosis of many common sports-related injuries of the hand. We review the common ligamentous and tendinous injuries of the hand including collateral ligament injuries, gamekeeper's thumb, extensor mechanism injuries, pulley injuries, boutonniere deformities, and mallet and jersey lesions. The mechanism of injury, clinical presentation and treatment, pertinent anatomy, and imaging findings are discussed.

We report a case of a 70-year-old man with a history of prostatic adenocarcinoma and a 3-month history of right hemiscrotal swelling. The patient underwent a CT scan, scrotal ultrasound, and F-18 FDG-PET scan to evaluate for metastatic prostate cancer. The CT scan demonstrated an ill-defined soft-tissue mass extending along the right gonadal vein. Scrotal ultrasound revealed a heterogeneous right testicular mass. The F-18 FDG-PET scan demonstrated intense hypermetabolic activity along the course of the right gonadal vein extending to the right hemiscrotum. Subsequent right radical orchiectomy and pathologic examination revealed a B-cell lymphoma, infiltrating the testicular parenchyma, spermatic cord, gonadal vessels, and adjacent soft-tissues. Lymphoma or other tumors rarely infiltrate the spermatic cord, and have only very rarely been demonstrated on PET imaging.

).High-resolution ultrasonography (US) has proven to be a powerful diagnostic tool in the evaluation of musculoskeletal trauma including injuries of the tendons, ligaments, muscles, and nerves, as well as musculoskeletal diseases including joint effusions, synovitis, bursitis, articular erosions, joint bodies, soft tissue infections, and soft tissue tumors and tumor-like conditions. It can also diagnose radiographically occult fractures and joint and bone infections. 1 This imaging modality provides results in the diagnosis of musculoskeletal trauma and diseases comparable with MR imaging. 2 Rapid advances in US technologies in the past 10 years have resulted in significant improvement in image quality. Development of a variety of US transducers, compound imaging, improved focusing, and transducers with large and small fields of view are available for different musculoskeletal applications, resulting in better B-mode gray-scale image quality and information from Doppler imaging. AbstractDuring the past 2 decades, high-resolution ultrasonography (US) has been increasingly utilized in the diagnosis of musculoskeletal trauma and diseases with results comparable with MR imaging. US has an advantage over other cross-sectional modalities in many circumstances due to its superior spatial resolution and ability to allow dynamic assessment. When performing musculoskeletal US, the examiner has to be knowledgeable in the complex anatomy of the musculoskeletal system and US imaging technique. Additionally, he or she must be familiar with several common imaging artifacts in musculoskeletal US that may be mistaken for pathology, as well as several artifacts that frequently accompany pathologic conditions. These artifacts may occur with both Bmode gray-scale and Doppler imaging. In this article, we discuss common artifacts seen in musculoskeletal US and techniques to avoid or minimize these artifacts during clinical US examinations.