Musculoskeletal Ultrasound
What is Diagnostic Musculoskeletal Ultrasound (MSK-US)?
In veterinary school we learn a lot about joint pathology (e.g. osteoarthritis, OCD) and long bone pathology (e.g. fracture, neoplasia) . We don’t learn as much about so called soft tissue injuries such as tendon, ligament and muscle injury. This is unfortunate because there are SO many soft tissue injuries. These are those nagging injuries that get better with rest and NSAID only to return again and again when activity is resumed. Before long the NSAID doesn’t work at all and rest may or may not help. No one wants to continuously limit their dog’s active lifestyle indefinitely! It’s important to get to the bottom of the problem sooner than later. The longer these soft tissue injuries persist the harder they are to treat and the poorer the prognosis for full recovery. If lameness returns after 1 round of rest and NSAIDs it’s time to dig deeper.
Radiographs are helpful in evaluating joints and long bones. However, once a soft tissue injury is suspected a thorough sports medicine evaluation helps narrow the differential diagnosis list. The next diagnostic tool is musculoskeletal ultrasound.
In order to use this tool properly the following are important:
Specific ultrasound machine settings and probe frequencies for identifying soft tissue injury.
Extensive knowledge of anatomy and pathology.
Training in MSK-US is important. Although Dr. Mich is not a board certified radiologist she is a board certified sports medicine and rehabilitation specialist with specific MSK-US training.
Common tissues affected by soft tissue injury and evaluated with this tool are:
Shoulder: supraspinatus, infraspinatus, biceps brachii, medial shoulder structures
Elbow: extensor and flexor tendons of origin
Carpus: flexor carpi ulnaris
Stifle: long digital extensor origin, meniscus
Achilles mechanism: insertion and muscle bellies
Iliopsoas muscle and insertion at the lesser trochanter
Once a tendon, ligament or muscle injury is diagnosed treatment plan often includes ultrasound guided injection of orthobiologic such as PRP (platelet rich plasma) or ACP (autologous conditioned plasma). Left image normal longitudinal view of supraspinatus tendon. Image right depicts US guided injection of supraspinatus tendon.
For more information see the Shoulder Tendonopathy Mobility Memo Series
