What are the commonly used transducers in musculoskeletal Ultrasound?
The transducer frequency is one important determinant of image quality. The higher the frequency, the greater the spatial resolution of the images and the lower the degree of tissue penetration. It is important to select the transducer with the highest frequency that still allows penetration to the depth of the structure being imaged. Linear probes are preferable to curved probes for musculoskeletal US because the ultrasound waves are propagated parallel to the transducer surface, limiting artifacts during evaluation of linear structures such as tendons. The linear 12-5 MHz is the workhorse transducer for musculoskeletal US, while the linear 17-5 MHz transducer may be used for the evaluation of more superficial structures. The compact or “hockey stick” linear transducer is ideally suited for the evaluation of small joints and guiding procedures performed on the distal extremities where sharp contours allow for limited contact with the probe surface. The 5-9 MHz curvilinear transducer is less commonly used in musculoskeletal US but has a role in the evaluation of deep structures or patients with larger body habitus.