Topic 3 the shoulder Flashcards
What are the attachments of the supraspinatus muscle?
Supraspinous/fossa of the scapula
Upper facet of the greater tuberosity of the humerus
What are the attachments of the infraspinatus?
Infraspinous fossa of the scapula
Middle facet of the greater tuberosity of the humerus
What are the attachments of teres minor?
Infero medial border of the scapula
Lower facet of the greater tuberosity of the humerus
What are the attachments of the subscapularis?
Subscapula fossa of the scapula
Lesser tuberosity of the humerus
What are the attachments of the biceps brachii long head?
Supragelnoid tubercle’
Radial tuberosity
and fibrous lacertus
List some causes of shoulder pain
- rotator cuff pathology (degeneration, tears, calcific tendinosis) (most common)
- long head biceps pathology
- subacromial subdeltoid bursa pathology (most common)
- arthropathy of the glenohumeral or acromioclavicular joint (which may be of inflammatory or degenerative cause)
- osseous disease.
What is the typical presentation of rotator cuff pain?
- painful restricted arc
- pain along the deltoid insertion, and often into the elbow
- pain which disturbs the patient’s sleep
- a traumatic event which has caused the pain
- focal pain
What is ultrasound able to assess dynamically in the shoulder?
subacromial impingement, subcoracoid impingement, and biceps tendon subluxation dynamically. Dynamic compression of rotator cuff tears can aid in the assessment of cuff integrity.
What is MRI more useful at assessing in the shoulder?
instability, ligamentous injury, or suspected glenoid labral injury
When should xray be used?
Ultrasound is also of limited value in the evaluation of bony disorders, and plain radiography should be considered.
Ultrasound can be used to assess a long list of shoulder pathology. Name 5
• Rotator cuff tears • Full-thickness tear • Partial-thickness tear • Rotator cuff tendinopathy • Tendinitis • Calcific tendinitis • Mucoid degeneration • Attrition Effusions/synovitis • Subacromiodeltoid bursa • Subacromial impingement • Glenohumeral effusion • Long biceps tendon sheath • "Geyser" sign of acromioclavicular joint • Long head of the biceps tendon • Tenosynovitis • Tendinitis • Subluxations (see notes for more)
What history should you gather before commencing a shoulder scan?
- initial injury
- time period over which the problem has been present
- site of tenderness
- movements which cause maximum discomfort
- activities which bring on the pain
- previous treatment
- results of treatment
How would you ergonomically scan a shoulder?
- Seat the patient on an armless swivel chair, facing the sonographer, with both shoulders exposed to facilitate side to side comparison.
- The patient stool should be lower than yours, so you can comfortably extend your scanning hand to their shoulder height, maintaining your elbow tucked in as close to your side as possible.
What three categories should be used to describe tears?
Thickness, size, location
What are the different ways of describing the thickness of a supraspinatus tear?
• complete • full thickness • partial thickness o articular surface o bursal surface o insubstance/delamination
How do you describe the size of a supraspinatus tear?
• measure length x width
How do you describe the location of a supraspinatus tear?
- distance from biceps groove; or anterior, mid or posterior
* describe as proximal, mid or insertional (distal)
What is a global tear?
A shoulder which has tears in a number of tendons
Describe the possible appearances of a full thickness supraspinatus tear
- a hypoechoic or anechoic gap within the rotator cuff
- may also have a concave contour at its bursal border
- a greatly retracted tear can result in nonvisualization of the rotator cuff tendon
What can make visualisation and demonstration of the full thickness tear difficult?
- the gap between the retracted tendon end and the greater tuberosity or distal tendon stump may be filled with hypoechoic fluid or echogenic debris and granulation tissue.
- Alternatively, the subacromial-subdeltoid bursa (frequently thickened) and the deep surface of the deltoid muscle the defect created by the tear may occupy.
- Small foci of debris within the tear gap may give the appearance of mobile or “floating” bright spots
How can dynamic assessment help in classifying a full thickness tear?
one may be uncertain as to whether abnormal echotexture in the location of the rotator cuff represents a partial tear or a full-thickness tear with intervening granulation tissue and debris. Dynamic compression of the abnormal area may clarify this confusion by causing complex fluid and debris to swirl within the rotator cuff tear.
What is the cartilage interface sign?
• Fluid within the tear gap my accentuate visualization of the underlying humeral head articular cartilage owing to enhanced through transmission of the ultrasound beam, referred to as the “cartilage interface sign”
What are some ways of differentiating acute from chronic tears?
the findings of glenohumeral and bursal effusions are more common in acute tears.
Midsubstance tears, medial to the bone-tendon junction, are more likely to be acute
Severely retracted tears are more likely to be chronic.
What is one aspect of full thickness chronic tears that may make diagnosis difficult?
In chronic full-thickness tears, the tendon gap may be filled with noncompressible, complex echogenic debris and granulation tissue that are contiguous with the subacromial subdeltoid bursa, and this may give the false impression of rotator cuff volume
IN what demographic to partial thickness tears mot commonly occur?
- occur more commonly than full-thickness tears in younger patients
- most commonly occur in young athletes
What is the most common sub type of partial thickness tears?
• Partial articular-sided supraspinatus tears are the most common subtype
What is the most common cause of partial tears in the older population?
Tendon degeneration
What are the partial thickness tear sub types?
o Bursal sided
o Articular sided
o Intrasubstance
o Rim rent tear
What is a rim rent tear?
occurs at the articular side of the supraspinatus tendon, extending into the tendon footprint on the greater tuberosity
• most commonly seen in athletes who engage in overhead-throwing activities
What are the different grades of partial thickness tears?
Grade 1 <25%
Grade 2 25-50%
Grade 3 >50%
What is the ultrasound appearance of a bursal partial thickness tear?
o flattening of the bursal contour of the tendon
o may lead to an hourglass-like diameter shift between areas of normal and attenuated tendon
What ultrasound appearances are common to full and partial thickness tears?
o cortical irregularity of the greater tuberosity
o 75% positive predictive
o more severe in full-thickness tears
o represents bony remodeling with irregularity, pitting, and erosion
o A second sign that can be seen in both partial articular-sided and full-thickness tears is the “cartilage interface” sign
What is the correct way to measure a tear?
• Always measure the medial to lateral tear length should be made in long axis, and a measurement of the anterior to posterior tear width should be made on short-axis imaging.
After surgery what is the best way to diagnose a re tear?
• A gap within the tendon and nonvisualization of the tendon owing to retraction are the most reliable signs for a recurrent tear
What are some normal post surgical changes?
- loss of normal soft tissue planes and abnormal echotexture of the rotator cuff tendon
- Bony irregularity at the site of anchor placement is expected
- echogenic suture material within the tendon may contribute to the heterogeneous appearance
• A thinned tendon or one with subtle contour abnormality is considered intact.
What is shoulder tendinosis?
- degenerative process that may be associated with shoulder pain
- There is mucoid degeneration and frequently chondroid metaplasia
How does shoulder tendinosis appear on ultrasound?
o heterogeneous or hypoechoic
o tendon thickening
o loss of the normal fibrillar pattern
• Although discrete defects or tears are not encompassed by this diagnosis, they may coexist.
How does degenerative arthropathy appear on ultrasound?
- Osteoarthritis is common at the AC joint
- characterized by bone spurs—osteophytes—at the margin of articular surface
- may be small associated joint effusions
- echogenic intraarticular bodies, which may be calcified, can be observed
How does shoulder inflammatory arthropathy appear on ultrasound?
- including rheumatoid arthritis and ankylosing spondylitis
- may have glenohumeral effusion
- best assessed posteriorly, and a thickness of 3 mm or more from the humeral head to the capsule may represent effusion and/or synovial thickening
- Colour Doppler can help separate thickened synovium from complex intraarticular fluid.
- Bone erosions may also be present, characterized by bony cortical surface rounded or steplike deformations, often at the humeral head margins
What else may patient with inflammatory arthropathy present with?
• Patients with inflammatory arthritis may also be affected by subacromial-subdeltoid bursitis, in addition to rotator cuff and biceps tendon tears.
IN what demographic to partial thickness tears mot commonly occur?
- occur more commonly than full-thickness tears in younger patients
- most commonly occur in young athletes
What is the most common sub type of partial thickness tears?
• Partial articular-sided supraspinatus tears are the most common subtype
What is the most common cause of partial tears in the older population?
Tendon degeneration
What are the partial thickness tear sub types?
o Bursal sided
o Articular sided
o Intrasubstance
o Rim rent tear
What is a rim rent tear?
occurs at the articular side of the supraspinatus tendon, extending into the tendon footprint on the greater tuberosity
• most commonly seen in athletes who engage in overhead-throwing activities
What are the different grades of partial thickness tears?
Grade 1 <25%
Grade 2 25-50%
Grade 3 >50%