Orthopaedic Ultrasound Imaging

Physiotherapists along with other clinicians working in musculoskeletal medicine have considerable experience in making clinical assessments and diagnoses. Ultrasound adds an important extra dimension to this by allowing direct visualisation of the soft tissues.

Muscles

Ultrasound imaging has for some time been used by physiotherapists to evaluate muscle activity, but it is also useful in evaluating muscle injury and tears. By examining in multiple planes tears can be localised and their extent assessed, along with the presence of haematomas making it possible to monitor healing objectively. By observing the interfaces between muscles and fascial planes the presence of adhesions causing tethering can be identified.

Ultrasound image of calf tear (medial head triceps)

Tendons

With ultrasound it is possible to look at tendons dynamically to assess not only their internal structure, but also adhesions, subluxations and pathological changes in surrounding tissues, such as tenosynovitis. Where tendons are superficial, ultrasound imaging gives better visualisation and resolution of internal architecture of tendons than MRI. Scanning tendons, though technically challenging, can be particularly enlightening when looking for abnormal changes, such as tendonopathy, partial and full thickness tears, calcinosis and neovascularisation.

EARLY EXPERIENCES OF PHYSIOTHERAPISTS USING SHOULDER ULTRASOUND

Bone

Although ultrasound is not the first choice for scanning bone, it is useful for looking at the periosteum to see if there is any disruption, and myositis ossificans  is also well seen. Visualising bony landmarks is also an important aid to orientation when scanning complex structures such as the rotator cuff (eg. identifying the bicipital groove)

Ultrasound image of left shoulder, transverse view through the bicipital groove. (C) is the coracoid

Nerves

Ultrasound is used to visualise nerves, and their appearance is similar to that of tendons. Some work has been done with ultrasound, examining the movement of nerves in conditions such as carpal tunnel syndrome (CTS). Similarly to tendons and muscle, it may be possible to evaluate adhesions affecting nerves, and subluxation of the ulna nerve is well seen. Pathological changes in nerves such as neuromas, along with thickening and changes in vascularity (seen in CTS) are often evaluated using ultrasound.

Vascular

Vascular structures are examined with the standard grey scale image along with Doppler ultrasound (which displays the blood flow).  It is often used to exclude DVT and to identify pathology within the carotid arteries, along with a range of other examinations.

Interventional

For physiotherapists in the UK, ultrasound imaging has an added role, guiding therapeutic injections and aspirations. Ultrasound allows reliable accurate placement of the needle tip within the desired structure which has been shown shown to improve efficacy.