Diagnostic imaging
Musculoskeletal ultrasound
Musculoskeletal ultrasound uses high-frequency sound waves to image soft tissues — tendons, ligaments, muscles, nerves and the surfaces of joints. Two features distinguish it from other imaging: it is dynamic, so structures can be watched while the limb moves, and it is interactive, so the person scanning can ask where it hurts and place the probe there. It involves no ionising radiation and can be performed during the consultation.
What it images well
Superficial soft-tissue structures are where ultrasound performs best.
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Tendons
Thickening, degenerative change, partial and full-thickness tears. Rotator cuff, Achilles, patellar and elbow tendons are all readily assessed.
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Bursae and fluid
Bursal distension and joint effusion are shown clearly, and fluid can be sampled under direct vision where that is needed.
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Nerves
Swelling of a nerve at a site of entrapment, such as the median nerve at the carpal tunnel, can be seen and measured.
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Guidance for procedures
Needle placement for injections and aspirations can be watched in real time, which improves accuracy at small or deep targets.
Why dynamic assessment matters
This is the capability that other imaging does not have, and it changes what some questions can be answered.
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Structures under load
A tendon can be watched as the joint moves, which can reveal impingement or abnormal movement that a static image taken at rest does not show.
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Comparison with the other side
The unaffected limb can be scanned in the same session, which is useful where normal appearances vary between individuals.
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Correlation with symptoms
The probe can be placed exactly where the pain is, so a finding can be matched to the symptom rather than inferred from a report.
Limitations
Ultrasound is not a substitute for MRI, and treating it as one leads to missed diagnoses.
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It cannot see through bone
Structures inside a joint — the meniscus, the cruciate ligaments, the labrum — and bone marrow are not assessable. MRI remains the standard test for these.
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Depth is a constraint
Deep structures, particularly in larger patients, are harder to image well. The hip and the spine are less suited to it than the shoulder or the wrist.
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It is operator-dependent
Image quality and interpretation depend substantially on the person performing the scan, more so than with cross-sectional imaging.
Common questions
Is it as good as an MRI?
For superficial tendons and bursae it is comparable and has the advantage of dynamic assessment. For structures inside a joint, for bone, and for deep tissue, MRI is superior. They answer different questions.
Is it safe?
Yes. It uses sound waves rather than ionising radiation and has no known harmful effects at diagnostic intensities, so it can be repeated as often as needed.
Does it hurt?
No. Pressure from the probe over a tender area can be briefly uncomfortable, and that discomfort is itself part of the information.
Do I need to prepare?
No preparation is required for musculoskeletal scans. Clothing that allows access to the area is helpful.
General reference information, and not advice about your own case. It may not reflect the most recent guidance or what is offered on a given day — call (201) 408-5151 to check.
Schedule an appointment
Dr. Yoo Rehab Clinic welcomes new patients from across Northern New Jersey and New York City, including Englewood, Teaneck, Fort Lee, Palisades Park and Ridgefield. Call today to learn more about insurance, scheduling, and how we can help.
