Review of appendicitis: routine, complicated, and mimics.

Appendicitis is one of the most common sources of abdominal pain in the emergency setting and is generally considered a straightforward diagnosis. However, atypical appearances, non-visualization, and inconclusive features can make these cases more complicated. The objectives of this article are to review the differential diagnoses for right lower quadrant pain, discuss the imaging characteristics of simple appendicitis on computed tomography (CT), and provide guidance for equivocal cases, complicated appendicitis, and appendicitis mimics. This review will also discuss the identification and management of neoplasms of the appendix.

MRI of the Wrist Ligaments.

Technological advances in magnetic resonance imaging (MRI) have improved radiologists' ability to evaluate wrist ligaments. MRI interpretation often guides clinical management. This article aims to review the normal and pathologic appearance of intrinsic and extrinsic wrist ligaments with a focus on MRI. Variant anatomy, imaging pearls, and clinical significance are also discussed. Special attention is paid to key wrist ligaments that play a role in carpal stability.

Septic Arthritis: An Evidence-Based Review of Diagnosis and Image-Guided Aspiration.

OBJECTIVE. The purpose of this evidence-based review is to equip radiologists to discuss and interpret findings obtained with various imaging modalities, guide patient selection for percutaneous aspiration, and safely perform arthrocentesis to assess for infection in both native and prosthetic joints. CONCLUSION. Septic arthritis is an emergency that can lead to rapidly progressive, irreversible joint damage. Despite the urgency associated with this diagnosis, there remains a lack of consensus regarding many aspects of the management of native and periprosthetic joint infections.

Avulsion Injuries of the Hand and Wrist.

Injuries of the hand and wrist are frequently encountered in radiology. Avulsions of the hand and wrist are a heterogeneous group of injuries, but they often have a characteristic imaging appearance that relates to the intricate bone and soft-tissue anatomy and the mechanism of injury. The imaging appearance and this intricate form and function dictate treatment of hand and wrist avulsions. This article reviews frequently and infrequently encountered avulsion injuries and describes abnormalities that may mimic the imaging appearance of avulsions. Specifically discussed entities include the Bennett and reverse Bennett fracture, ulnar collateral ligament avulsion, radial and ulnar styloid process avulsion, triquetral avulsion, mallet and jersey finger, central slip avulsion, and acute and chronic volar plate avulsion injuries. Uncommon avulsion injuries are also described and include avulsions of the scapholunate ligament, extensor carpi radialis longus and brevis tendons, trapeziometacarpal ligament, radial collateral ligament, and flexor digitorum profundus tendon. Emphasis is placed on the relevant anatomy and typical imaging findings for each diagnosis, with pertinent clinical history, pathophysiologic evaluation, and treatment discussed briefly. Understanding the anatomy and expected imaging findings can aid the radiologist in recognizing and characterizing these injuries.©RSNA, 2020.

Intramuscular Placement of Birth Control Device: A Multimodality Case and Review.

Implantable forms of birth control have been used as a means for convenient and effective medication delivery. Nexplanon® (Merck Sharp & Dohme B.V., Haarlem, the Netherlands) is an implantable birth control device placed in the subcutaneous tissue of the upper medial arm during an in-office procedure. The location of the device is usually confirmed by palpation during a physical exam. In cases where the device is non-palpable, imaging may aid in localization. Implantable birth control devices have a characteristic radiologic appearance, and the location of the device can be confirmed by utilizing ultrasound and/or radiography. Occasionally, sonographic and radiographic studies may have equivocal results necessitating advanced imaging with computed tomography (CT) and/or magnetic resonance imaging (MRI). Subcutaneous location of the device is essential for efficacy and safety. An intramuscular position of the device is inappropriate and may lead to insufficient medication delivery and/or injury to the deep soft tissues. This case reviews the imaging features of a Nexplanon device which had been inappropriately placed into the muscle.