[Use of clinical ultrasound in primary care: ultrasound in posterior leg pain].

Back leg pain is a common complaint in primary care and is especially linked to the sports and work field. The most common cause is trauma, which can lead to injuries that can range from tendinosis to ruptures, although other causes may imply more complex and serious pathology, such as venous thrombosis or arterial injuries. This type of pathology is also important because it can be the manifestation of neoplastic, infectious, or rheumatic disease. Current technical advances in ultrasound equipment, added to increased availability, good cost-effectiveness ratio, good patient tolerance, and the chance to execute a real-time dynamic assessment, have made ultrasonography the technique of choice in leg pathology evaluation. For this reason, our current objective is to carry out a clear description of the technique that allows it to extend its use in routine clinical practice.