Musculoskeletal Ultrasound: An Update - This article provides an update regarding the field of musculoskeletal ultrasound. Because of recent technologic improvements, including high-resolution linear array and matrix probes, tissue harmonic imaging, extended field of view capability, and improved Doppler sensitivity, the field of musculoskeletal ultrasound is rapidly evolving, improving, and expanding around the world. In addition, continued emphasis on health care cost containment has heightened interest in the modality. Examination technique and interpretation of ultrasound of the rotator cuff is emphasized, followed by a discussion of a variety of other emerging applications including ultrasound of the hand and wrist, hip, elbow, and ankle and foot./