Diagnostic ultrasound ( PDFDrive )

CHAPTER
24
The Shoulder
Colm McMahon and Corrie Yablon
SUMMARY OF KEY POINTS
• In the diagnosis of full-thickness rotator cuff tears,
ultrasound is of comparable accuracy to magnetic
resonance imaging, although it may be less accurate in the
diagnosis of partial-thickness tears.
• The key to scanning the shoulder is meticulous technique
using a protocol that systematically evaluates the entirety
of the shoulder.
• Understanding of optimal patient positioning, probe
orientation, and shoulder anatomy is critical to effective
diagnostic shoulder ultrasound.
• Ultrasound allows dynamic assessment of subacromial and
subcoracoid impingement, biceps subluxation, and rotator
cuff integrity.
CHAPTER OUTLINE
CLINICAL PERSPECTIVE
SHOULDER ANATOMY
SCAN TECHNIQUE
Biceps Tendon Evaluation
Subscapularis Tendon Evaluation
Supraspinatus Evaluation
Infraspinatus, Teres Minor, and
Posterior Shoulder Evaluation
Rotator Cuff Musculature
Evaluation
ROTATOR CUFF DEGENERATION
AND TEARS
Background
Tendinosis
Full-Thickness Rotator Cuff Tears
Partial-Thickness Rotator Cuff Tears
Postsurgical Rotator Cuff
Muscle Atrophy
Subacromial-Subdeltoid Bursa
Calciic Tendinitis
LONG HEAD BICEPS TENDON
PATHOLOGY
ARTHROPATHY
Degenerative
Inlammatory
PITFALLS IN SHOULDER
ULTRASOUND
CONCLUSION
CLINICAL PERSPECTIVE
he human shoulder represents an intricate balanced anatomic
system capable of exerting force in multiple directions, in multiple
diferent positions, all possible because of a number of static
and dynamic structures, which when functioning well provide
for the competing needs of movement and stability. Proper
function of the shoulder is critical for activities ranging from
the most basic of daily life to many sporting pursuits including
those of the throwing athlete. he shoulder is, however, prone
to injury, related to anatomic factors such as subacromial
impingement. 1,2 Shoulder pain and limitation of motion are
very common causes for quality-of-life impairment, medical
resource use, and loss of workplace productivity. 3-7 In fact,
about 50% of adults have at least one episode of shoulder pain
yearly. 8 Clinical presentation varies from acute injury 9,10 to more
chronic dysfunction, which is more common with advancing
age. 11
Although shoulder pain and dysfunction are common
clinical complaints, the underlying etiology is variable, with
causes including rotator cuf pathology (degeneration, tears,
calciic tendinosis), long head biceps pathology, subacromial
subdeltoid bursa pathology, arthropathy of the glenohumeral or
acromioclavicular joint (which may be of inlammatory or
degenerative cause), or osseous disease. Of these, subacromial
subdeltoid bursitis and rotator cuf pathology are the most
common causes of symptomatic shoulder disease. 12 Correct
diagnosis is crucial for treatment decision making, allowing
appropriate management with surgical or nonsurgical treatment,
which may diminish the personal and societal efect of shoulder
problems. 13,14 Of course, clinical history taking and examination
are intrinsic parts of patient assessment, but the accuracy of
clinical examination in diagnosis of the cause of shoulder pain
is both modest and variable. 15-20
In this clinical and socioeconomic setting, the advantages of
ultrasound as a diagnostic test are myriad, as this technique is
accurate, cost-efective, and well tolerated by patients. In the
diagnosis of full-thickness rotator cuf tears, ultrasound is of
comparable accuracy to magnetic resonance imaging (MRI),
although it may be less accurate in the diagnosis of partialthickness
tears. 21-30 Ultrasound can also determine muscle atrophy,
an important parameter in predicting successful surgical outcome
of rotator cuf repair. 31 Ultrasound is a good alternative to MRI
in patients who are claustrophobic, are of large size, or have
877