Musculoskeletal Ultrasound

Musculoskeletal ultrasound is an imaging test that uses sound waves to produce real-time pictures of muscles, tendons, ligaments, joints, and soft tissues anywhere in the body.

A small handheld device called a transducer (a probe that sends and receives sound waves) is pressed gently against your skin. The sound waves bounce off internal structures and return as signals that a computer turns into moving images on a screen. Because the images update live, the doctor can watch a tendon or joint in motion, which is something X-rays and MRI cannot do. No radiation is involved at any point.

Doctors in rheumatology (the specialty that treats joint and autoimmune diseases) and sports medicine use musculoskeletal ultrasound to diagnose a wide range of conditions affecting the moving parts of the body. It is especially useful when the problem lies in soft tissue rather than bone.

• Tendon injuries — tears, thickening, or inflammation (tendinopathy) in structures such as the rotator cuff in the shoulder, the Achilles tendon at the heel, or the patellar tendon at the knee
• Ligament sprains and partial tears around any joint
• Muscle tears or haematomas (pockets of blood that form after an injury)
• Bursitis — swelling of the small fluid-filled sacs (bursae) that cushion joints
• Joint effusion — excess fluid inside a joint, which can be drained using ultrasound guidance
• Synovitis — inflammation of the membrane lining a joint, common in rheumatoid arthritis
• Carpal tunnel syndrome — compression of the nerve in the wrist
• Ganglion cysts — benign (non-cancerous) fluid-filled lumps near joints or tendons
• Gout and calcium crystal deposits detected as bright spots within a joint or tendon
• Nerve compression or thickening in any part of the body
• Guiding injections of anti-inflammatory medication or joint aspirations (fluid removal) in real time

This scan is generally not the right first choice when the problem is suspected to be primarily inside a bone (for example, a stress fracture deep within the bone), when a detailed picture of the spine or spinal cord is needed, or when cartilage damage inside a large joint needs precise measurement. In those situations, your doctor will usually recommend X-ray or MRI instead.

• Deep bone injuries or suspected fractures inside the bone shaft
• Detailed assessment of spinal discs or the spinal cord
• Precise staging of cartilage loss inside a joint (where MRI gives more detail)
• Any area where thick bone blocks the path of sound waves, making images unclear

Musculoskeletal ultrasound used purely for imaging is considered one of the safest diagnostic tests available. It does not use radiation and nothing enters the body, so there are very few risks to report.

• Mild skin discomfort from the pressure of the probe, especially over a bruised or inflamed area — this is temporary
• A small number of patients find the cool gel applied to the skin slightly uncomfortable
• Rarely, an unclear image if the area being examined is very deep or if the patient has a large body frame — in this case the doctor may request a different scan
• If the ultrasound is being used to guide an injection or fluid drainage at the same time, additional risks related to that procedure apply (such as temporary soreness at the injection site, a small risk of infection, or bruising) — your doctor will explain these separately

Preparation for a musculoskeletal ultrasound is usually minimal. In most cases, no fasting is required, and there is no need to stop routine medications before the scan. However, if the ultrasound will be combined with an injection or fluid drainage, your doctor may give specific instructions about blood thinners or other medications beforehand.

On the day of the scan, wear loose, comfortable clothing that gives easy access to the area being examined — for example, a sleeveless top for a shoulder scan or shorts for a knee scan. Remove any jewellery near the area. No special diet, smoking restrictions, or alcohol guidelines are typically needed for the imaging alone.

Some clinics may ask for recent relevant X-rays or MRI images to be brought along so the radiologist or rheumatologist can compare them. Bring a list of your current symptoms, how long you have had them, and any previous diagnoses related to the joint or muscle being examined.

The scan itself usually follows these steps, though the exact order and duration vary by clinic and body part:

• You are positioned on an examination table — lying down, seated, or with the limb placed in a specific angle — so the area of interest is easy to reach
• A water-based gel is applied to the skin over the area to be scanned; the gel helps sound waves travel smoothly between the probe and your skin
• The sonographer (imaging technician) or doctor moves the transducer slowly over the skin in different directions to capture images from multiple angles
• You may be asked to move the joint, contract a muscle, or hold a position so the doctor can watch the tissue in motion
• If the scan is guiding a procedure such as an injection, the doctor will use the live image on screen to direct the needle accurately
• The gel is wiped off and you can usually dress and leave straight away

When the scan is used for imaging only, there is essentially no recovery period. You can eat, drink, drive, and return to your normal activities immediately after leaving the clinic. The gel leaves no mark and washes off easily. If the ultrasound was combined with a procedure such as a joint injection or fluid aspiration (draining excess fluid from the joint), some additional aftercare will apply and your doctor will explain those instructions before you leave.

• No restrictions on diet, exercise, or daily activities after a scan performed for imaging alone
• If a joint injection or aspiration was performed at the same time, rest the affected joint for the remainder of that day and watch for unusual swelling, warmth, or redness — report these to your doctor promptly
• Your images will usually be reviewed by the doctor during or shortly after the scan; in some clinics a written report is sent to your referring doctor within a few days
• Attend any follow-up appointment your rheumatologist or sports medicine doctor schedules to discuss the results and plan next steps
• If the scan confirmed a tendon or muscle injury, your doctor may recommend physiotherapy (exercise-based rehabilitation) and will advise on how to protect the area while it heals
• Keep records of your scan images and report — these are useful for tracking changes over time if repeat scans are needed in the future