Point-of-care ultrasound brings great value to patient care in orthopedic practice, especially for soft tissue problems. It offers safe, cost effective, and real-time evaluation for soft tissue pathologies and helps narrow down the differential diagnosis.
There are variety of soft tissue lesions in orthopedic practice with classic clinical presentation that may not necessitate ultrasound examination for confirmation of diagnosis, for example ganglion cyst. However, there is value in performing an ultrasound scan for these common soft tissue lesions.
Ganglion cyst on the dorsum of the wrist or radial-volar aspect of the wrist are confirmed based on clinical examination and presentation. Adding ultrasound examination can help differentiate classic ganglion cyst from some rare findings like Lipoma, anomalous muscles, or soft tissue tumors. Ultrasound examination may also be helpful in finding the source of the ganglion cyst or the stalk of the ganglion cyst. This can help pre-surgical planning if resection of the ganglion cyst is desired by the patient and recommended by the surgeon, because arthroscopic or traditional surgical approach may be needed based on the location of the stalk or neck of the cyst.
Images 1 and 2 show examples of two different patients with similar presentation of slow growing mass on the digit. Image 1 from patient 1 shows a solid tumor overlying the flexor tendons of the digit, where the mass was palpated. Image 2 from patient 2, shows a cystic mass overlying the tendons of the digit. In both of the cases, masses were painless and slow growing with minimal to no discomfort. Ultrasound is a great tool in differentiating solid vs cystic lesions and can help avoid attempted aspiration of a solid mass when the mass is presented in an area of classic ganglion cyst’s usual presentation.
Another soft tissue problem, where ultrasound is a superior imaging tool is tendon pathology. Ultrasound can help differentiate tendinosis, tenosynovitis, or tendon tears.
In tenosynovitis, tendon by itself shows normal echotexture and uniform appearance but the tenosynovium that surrounds the tendon gets inflamed and appears as hypoechoic halo around the tendon, for example, in image 3, tendons of the first dorsal compartment of the wrist show uniform thickness and fibrillar echotexture, however there is hypoechoic swelling around the tendons, this is an example of tenosynovitis of first dorsal compartment of the wrist.
In tendinosis, tendon loses its fibrillar pattern and appears swollen and may show vascularity on color ultrasound, which is suggestive of neoangiogenesis or angiofibroblastic proliferation. For example, in Image 4, the tendons of the first dorsal compartment of the wrist show focal enlargement, hypoechoic swelling, and loss of normal fibrillar echotexture and tendon appears disorganized with evidence of increased vascularity on color ultrasound. This is an example of tendinopathy or tendinosis.
Focal tendon tears appear as anechoic or hypoechoic focal defects in tendon substance. Image 5 shows partial tear of the triceps tendon from the olecranon process. The partial tear appears as a focal hypoechoic defect in the tendon, which is confirmed in the long and short axis scan of the tendon.
In full thickness tears, the tendon is seen retracted proximally with no fiber attachment at the tendon foot print. Image 6 shows example of a full thickness complete tear of the supraspinatus tendon from its bony attachment at the greater tubercle. The tendon has retracted proximally and the retracted stump is not visible on ultrasound examination.
Point-of-care ultrasound adds significant value to clinical examination in orthopedic setting. It enhances the understanding of a patient’s problem, increases confidence in care provided, and high patient satisfaction is reported.
In what unexpected ways do you find ultrasound to be useful? Do you have additional tips for using ultrasound in orthopedics? Comment below or let us know on Twitter: @AIUM_Ultrasound.
Mohini Rawat, DPT, MS, ECS, OCS, RMSK, is program director of Fellowship in Musculoskeletal Ultrasonography at Hands On Diagnostics and owner of Acumen Diagnostics. She is ABPTS Board-Certified in Clinical Electrophysiology; ABPTS Board-Certified in Orthopedics; registered in Musculoskeletal Sonography, APCA; and has an added Point-of-Care MSK Soft Tissue Clinical Certificate.