Rotator Cuff Imaging Techniques.
Last updated Wednesday, January 26, 2005
Cuff tendon imaging
A number of different studies are available for imaging the rotator cuff.Deciding to order tests Each of these tests adds both information and expense to the
evaluation of the patient; health care resources can be conserved by
only ordering imaging tests if the results are likely to change the
management of the patient. Patients under the age of 40 without a major
injury or weakness are unlikely to have significant cuff defects; thus
cuff imaging is less likely to be helpful in their evaluation. At the
other extreme, patients with weak external rotation and atrophy of the
spinatus muscles whose plain radiographs show the head of the humerus
in contact with the acromion (see figures 16 and 17) do not need cuff
imaging to establish the diagnosis of a rotator cuff defect. Finally,
the initial management of patients with nonspecific shoulder symptoms
and an unremarkable physical examination is unlikely to be changed by
the results of a cuff imaging test. Cuff imaging is strongly indicated
when it would affect treatment, such as in the case of a 47-year-old
with immediate weakness of flexion and external rotation after a major
fall on the outstretched arm or shoulder dislocation. Imaging the cuff
is also important when symptoms and signs of cuff involvement do not
respond as expected, for example, symptoms of "tendinitis" or
"bursitis" that do not respond to three months of rehabilitation.
A review of the literature suggest that, in experienced hands,
arthrography, MRI, ultrasound and arthroscopy each yield sufficient
accuracy for making the diagnosis of a full thickness cuff tear.
(Chiodi and Morini, 1994, Crass, Craig, 1984, D'Erme, DeCupis, 1993,
Grana, Teague, 1994, Mack, Nyberg, 1988, Owen, Iannotti, 1993,
Paavolainen and Ahovuo, 1994, Palmer, Brown, 1993, Quinn, Sheley, 1995,
Robertson, Schweitzer, 1995, Tuite, Yandow, 1994, van-Moppes, Veldkamp,
1995, Wang, Shih, 1994) Arthrography For many years the single contrast shoulder arthrogram has been the
standard technique for diagnosing rotator cuff tears. In this test,
contrast material is injected into the glenohumeral joint (see figure
18); after brief exercise, radiographs are taken to reveal
intravasation of the dye into the tendon (see figures 18 and 19) or
extravasation of the contrast agent through the cuff into the
subacromial subdeltoid bursa (see figure 21). In 1933, Oberholzer
(Oberholtzer, 1933) used air as a contrast agent, injecting it into the
glenohumeral joint prior to radiographic evaluation. Air contrast is
still useful in those patients allergic to iodine. In 1939, Lindblom
used opaque contrast opaque medium. (Lindblom, 1939a, Lindblom, 1939b,
Lindblom and Palmer, 1939) Since then iodinated contrast media have
been the standard for single-contrast arthrography. A number of
extensions of the basic technique have been published. (Ahovou,
Paavolainen, 1984, Kerwein, Rosenburg, 1957, Killoran, Marcove, 1968,
Neer, 1983, Neviaser, 1980, Resnick, 1981, Samilson, Raphael, 1961)
Pettersson (Pettersson, 1942) and Neviaser et al (Neviaser,
Neviaser, 1994) demonstrated the effectiveness of arthrography in
revealing deep surface partial-thickness cuff tears (see figures 19 and
20), however, arthrography cannot reveal isolated midsubstance tears or
superior surface tears. Craig (Craig, 1984) described the "geyser sign"
in which dye leaks from the shoulder joint through the cuff into the
acromioclavicular joint. The presence of this sign suggests a large
tear with erosion of the undersurface of the acromioclavicular joint
(see figures 22 and 23). Double-contrast arthrography using both air
and iodinated material may enhance the resolution of arthrography.
(Ahovou, Paavolainen, 1984, Ellman, Hanker, 1986, Ghelman and Goldman,
1977, Kerwein, Rosenburg, 1957) Berquist and associates (Berquist,
McCough, 1988) reported on the use of single- and double-contrast
arthrograms to evaluate the size of the cuff tears seen at surgery.
Their ability to accurately predict one of four cuff tear sizes (small,
medium, large, and massive) was just over 50 per cent. The reported
incidence of false-negative arthrograms in the presence of surgically
proven cuff tears ranges from 0 to 8 per cent. (See references Hawkins,
Misamore, 1985, Hazlett, 1971, Mink, Harris, 1985, Neviaser, 1971,
Post, Silver, 1983, Samilson and Binder, 1975, Wolfgang, 1978.) The
anatomical resolution of shoulder arthrography can be enhanced to a
certain degree by obtaining tomograms with the contrast material in
place to give information about the size and location of the tear and
the quality of the remaining tissue. Further resolution can be obtained
by performing double-contrast arthrotomography. (Freiberger, Kaye,
1979, Goldman, Dines, 1982, Goldman and Gehlman, 1978, Kilcoyne and
Matsen, 1983) Kilcoyne and Matsen (Kilcoyne and Matsen, 1983) used
arthropneumotomography to evaluate the size of the cuff tear and the
quality of the residual tissue. They found a good correlation with the
surgical appearance.
The accuracy of arthrography does not seem to be enhanced by digital subtraction. (Farin and Jaroma, 1995b)
The subacromial injection of contrast material (bursography) has
been used to evaluate the subacromial zone and the upper surface of the
rotator cuff. (See references Fukuda, 1980, Fukuda, Mikasa, 1987, Lie
and Mast, 1982, Lindblom, 1939a, Lindblom, 1939b, Lindblom and Palmer,
1939, Mikasa, 1979, Nelson, 1952, Strizak, Danzig, 1982) Fukuda
reported six patients having normal arthrograms and positive
bursograms, which he defined as pooling of the subacromially injected
contrast in the cuff tissue. He reported an overall accuracy for
bursography of 67 per cent when compared with operative findings.
Although lesions can be identified on this type of examination,
criteria for making diagnoses have not been rigorously defined. Magnetic resonance imaging Magnetic resonance imaging can reveal information about the tendon
and muscle. Seeger and coworkers (Seeger, Gold, 1988) and Kneeland and
associates (Kneeland, Middleton, 1987) provided initial information on
the use of magnetic resonance to image the cuff; however, they did not
document the sensitivity and selectivity of this method. Crass and
Craig (Crass and Craig, 1988) concluded that the accuracy of MRI in
diagnosing cuff pathology is unknown. Kieft and associates (Kieft,
Bloem, 1988) reported on 10 patients with shoulder symptoms evaluated
with MRI and arthrography. Arthrography showed a tear in three
patients, whereas MRI detected none of them.
In a recent retrospective study by Robertson et al (Robertson,
Schweitzer, 1995), the authors found that full-thickness tears of the
rotator cuff can be accurately identified at MR imaging with little
observer variation; however, consistent differentiation of normal
rotator cuff, tendinitis, and partial thickness tears is difficult.
Iannotti et al recently described the sensitivity, specificity and
predictive value of MRI for different clinical conditions. (Iannotti,
Zlatkin, 1991) Ultrasonography In experienced hands, ultrasonography can noninvasively and non
radiographically reveal not only the integrity of the rotator cuff, but
also the thickness of its various component tendons. In 1982, one of us
(FAM) observed during prenatal ultrasonography that movement
dramatically enhanced the resolution during real-time imaging of a
fetal hand. Similarly, adding a dynamic element to the sonographic
evaluation of the rotator cuff significantly improves its resolution:
moving the shoulder through even a small arc helps to distinguish the
cuff tendons from the humeral head, deltoid and acromion. The
importance of movement during the ultrasound examination was recently
reemphasized by Drakeford et al. (Drakeford, Quinn, 1990) Our initial
series of ultrasound examinations of the shoulder was presented in
1983. (Farrer, Matsen, 1983 March 10-15) Since that time the criteria
for diagnosing cuff lesions have evolved, as have the quality of the
equipment and the technique. Much of this work was carried out by and
as a result of the stimulation of the late Lawrence Mack. (Mack and
Matsen III, 1995, Mack, Matsen III, 1985, Mack, Nyberg, 1988) He
demonstrated that by careful positioning and by knowledge of the
dynamic anatomy of the cuff the experienced ultrasonographer can image
selectively the upper and lower subscapularis, the biceps tendon, the
anterior and posterior supraspinatus, the infraspinatus, and the teres
minor. Defects are revealed as absence of the normal tissue echoes and
failure of the tissue to move appropriately with defined humeral
movements (see figures 22 and 23). In his series of 141 patients from
the University of Washington Shoulder Clinic (Mack, Matsen III, 1985),
Mack demonstrateda specificity of 98 per cent and a sensitivity of 91
per cent in comparison to surgical findings. Most of the false-negative
results occurred in patients found to have tears less than 1 cm in
size. (Mack, Matsen III, 1985)
Ultrasonography has the advantages of speed and safety. In addition,
it provides the important benefit of practical bilateral examinations
(which, although theoretically possible with arthrography, MRI and
arthroscopy, are usually not done for reasons of cost, risk and time).
Ultrasonography also allows the shoulder to be examined dynamically and
provides the opportunity to show the results to the patient in real
time. Yet another advantage is its low cost: a bilateral shoulder
ultrasound is usually half the cost of a unilateral arthrogram and
one-eighth the cost of a unilateral shoulder MRI. While some series
have reported less accuracy with ultrasonography than arthrography,
others have pointed to its high degree of accuracy, noninvasiveness,
and effectiveness in experienced hands. (Brenneke and Morgan, 1992,
Collins, Gristina, 1987, Crass and Craig, 1988, Crass, Craig, 1984,
Middleton, Edelstein, 1985, Middleton, Reinus, 1986a, Middleton,
Reinus, 1986b, Olive and Marsh, 1992, Paavolainen and Ahovuo, 1994,
Taboury, 1992, Wiener and Seitz, 1993) Ultrasonography has been applied
to the evaluation of recurrent tears, (Crass, Craig, 1986) as well as
incomplete tears. (Crass, Craig, 1985) Seitz and coworkers (Seitz,
Abram, 1987 Jan) compared arthrography, ultrasonography, and MRI for
the detection of cuff tears in 25 patients. They found that
ultrasonography was the most helpful study in accurately documenting
the size and location of the tear when it existed. MRI suffered from
problems of image resolution. Arthrography was reliable in determining
full-thickness tears, but correlation with size and location of the
tear was difficult. Middleton (Middleton, 1994) concluded that
"Shoulder sonography is a valuable means of evaluating the rotator cuff
and biceps tendon. In experienced hands, it is as sensitive as
arthrography and magnetic resonance imaging for detecting rotator cuff
tears and abnormalities of the biceps tendon. Because sonography is
rapid, noninvasive, relatively inexpensive, and capable of performing
bilateral examinations in one sitting, it should be used as the initial
imaging test when the primary question is one of rotator cuff or biceps
tendon abnormalities."
In a recent review of the literature, Stiles and Otte concluded that
the accuracy of ultrasound in experienced hands was at least as good as
that of MRI. (Stiles and Otte, 1993)
Recent investigations have again confirmed the value of sonography.
In a study of 4588 shoulders, Hedtmann and Fett (Hedtmann and Fett,
1995) found that the overall sensitivity in diagnosing cuff tears was
97% in full thickness tears and 91% in partial thickness tears. The
false negative rate was less than 2% for an overall accuracy of 95%.
The supraspinatus was involved in 96%, the infraspinatus in 39%, the
subscapularis in 10% and the long head of the biceps in 34%. The
authors also developed an approach for measuring the degree of
retraction of the torn tendon. Farin and Jaroma (Farin and Jaroma,
1995a) examined 184 patients for possible acute traumatic tears.
Ultrasonography demonstrated 42 (91%) of 46 full-thickness tears and
seven (78%) of nine partial-thickness tears. Ultrasonography showed
more extensive tears than were found at surgery in four (4%) of 98
patients and less extensive tears in seven (7%) of 98 patients.
Sonographic patterns consisted of a defect in 31 (63%), focal thinning
in 10 (21%), and nonvisualization in 8 (16%).
Van-Holsbeeck et al (Van-Holsbeeck, Kolowich, 1995) found that a
7.5-MHz commercially available linear-array transducer and a
standardized study protocol yielded a sensitivity for partial thickness
tears of 93%, and a specificity of 94%. The positive predictive value
was 82%, and the negative predictive value was 98%. Similar results are
reported by others. (van-Moppes, 1995) Hollister et al (Hollister,
Mack, 1995) studied the association between sonographically detected
joint fluid and rotator cuff disease. In 163 shoulders they found that
the sonographic finding of intraarticular fluid alone (without bursal
fluid) has both a low sensitivity and a low specificity for the
diagnosis of rotator cuff tears. However, the finding of fluid in the
subacromial/subdeltoid bursa, especially when combined with a joint
effusion, is highly specific and has a high positive predictive value
for associated rotator cuff tears.
We find that expert ultrasonography provides the most efficient and
cost effective approach to imaging of the cuff tendons. The real time,
dynamic, and interactive examination of the rotator cuff provides the
physician and the patient with the information needed to make the
necessary management decisions in both primary and post surgical cuff
conditions.
For more information, please see this outside link: Ultrasound of the Shoulder Disclaimer
This resource has been provided by the University of Washington Department of Orthopaedics and Sports Medicine as general information only. This information may not apply to a specific patient. Additional information may be found at http://www.orthop.washington.edu or by contacting the UW Department of Orthopaedics and Sports Medicine.
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