Musculoskeletal Ultrasound – The Facts
Ultrasound imaging involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. Ultrasound exams do not use radiation (as in x-rays). Because ultrasound images are captured in real-time, they can show the structure and movement of the body’s internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions by providing images that show normal and abnormal muscles, tendons, ligaments, joints and soft tissue structures throughout the body.
What are some common uses of the procedure?
Ultrasound images are typically used to help diagnose:
- Shoulder: rotator cuff injuries, tendonitis, bursitis, impingement
- Elbow: medial epicondylitis (golfer’s elbow), lateral epicondylitis (tennis elbow)
- Knee: meniscal tears, ligament strains, Baker’s cyst
- Hip: bursitis, tendonitis
- Ankle sprains
- Carpal tunnel syndrome
- Stress fractures
Benefits
- Performed quickly in-office
- Non-invasive
- Comfortable
- Exam is performed in real-time with dynamic motion
- Can be easily compared to the non-injured side
- Instant results
- Differentiates between new and old injuries
- Cheaper than an MRI
- Can be used for guided injections directly into a problem spot
Risks
- For standard diagnostic ultrasound there are no known harmful effects on humans
Limitations
Ultrasound has difficulty penetrating bone and therefore can only see the outer surface of bony structures and not what lies within. For visualizing internal structure of bones or certain joints, other imaging modalities such as MRI,CT, and plain x-rays are typically used.
Procedure
For most ultrasound exams of the musculoskeletal system, the patient is seated on an examination table or a swivel chair. For some ultrasound exams, the patient is positioned lying face-up on an examination table.
A clear water-based gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The ultrasound technologist or physician then presses the transducer firmly against the skin in various locations, sweeping over the area of interest or angling the sound beam from a farther location to better see an area of concern.
During the examination, the technologist or physician is often able to point out problem areas in real-time (big difference compared to MRI). This ultrasound examination is usually completed within 15-30 minutes but may occasionally take longer.