Imaging Studies
Note the following:
-
Standard radiographic studies are used to rule out glenohumeral/acromioclavicular arthritis and os acromiale.
Anteroposterior view of the glenohumeral joint
Internal rotation view of the humerus with a 20° upward angulation to show the acromioclavicular joint
Axillary view - Most useful to rule out subtle signs of instability (eg, glenoid avulsion, Hill-Sachs lesion) and to visualize the presence of an os acromiale
Stryker notch view - Potential os acromiale is easily visualized and assessed when viewed through the humeral head
Supraspinatus outlet view - Most useful to assess the supraspinatus outlet space (If < 7 mm, the patient is more at risk for impingement syndrome.) and helps assess morphology of the acromion (A hooked acromion is more at risk for impingement.)
-
MRI is considered the imaging study of choice for shoulder pathology.
Advantages
Noninvasive
No radiation
Can detect intrasubstance tendon degeneration or partial rotator cuff tears
Can detect inflammation, edema, hemorrhage, and scarring
Can be used with an intra-articular contrast agent (eg, gadolinium), improving its ability to detect partial rotator cuff tears
Disadvantages
Often cannot accommodate patients with claustrophobia
Often cannot accommodate larger patients
Cannot accommodate patients with pacemakers, other metal implants, or particles
Dependent on quality of the MRI machine
Dependent on the skill of the technician performing the imaging and the radiologist interpreting the images
High cost
-
For arthrography, dye is injected into the glenohumeral joint and postinjection radiographs are taken to assess the integrity of the glenohumeral joint.
Can be used to evaluate rotator cuff tears (A finding of dye escaping out of the joint and into the subacromial space is diagnostic of a full-thickness rotator cuff tear.)
Advantages - Can be used in conjunction with a CT scan to evaluate intra-articular pathology (eg, Bankart tears) and has a low cost
Disadvantages - Size of the tears cannot be quantified, patient is exposed to radiation and contrast dye, procedure is invasive
-
Diagnostic arthroscopy
Minimally invasive, visual, surgical procedure to assess shoulder pathology
Can visualize and assess most shoulder pathology
May afford the patient and physician a chance to diagnose and treat the pathology with one procedure
Disadvantage - May miss capsular-sided, partial-thickness tears
-
Note: A workup for other, more systemic processes may be included as clinically indicated.
Sonoelastography (SE) is a new technique that can assess differences in tissue stiffness. A study investigated the performance of sonoelastography (SE) for the differentiation of supraspinatus (SSP) tendon alterations of tendinopathy compared to magnetic resonance imaging (MRI) and conventional ultrasonography (US). The study concluded that SE is valuable in the detection of the intratendinous and peritendinous alterations of the SSP tendon and has excellent interobserver reliability and excellent correlation with MRI findings and conventional ultrasonography findings. [9]
A study by Lee et al evaluated the relationship between tendon stiffness on sonoelastography and the MRI tendinosis grade in patients with rotator cuff tendinopathy. The study found that the MRI tendinosis grade is associated with stiffness assessed using sonoelastography in patients with rotator cuff tendinopathy. [10]
