Dr. McMonagle is an Associate Professor of Radiology, Musculoskeletal Radiology Fellow, and Dr. Vinson
is an Assistant Professor of Radiology, Musculoskeletal Radiology
Division, Department of Radiology, Duke University Medical Center,
Linking the axial trunk and upper extremity, the
shoulder joint plays an imperative role in most daily activities,
allowing us to position our hands in space. Further, the joint acts as a
small fulcrum for a long lever arm, predisposing the rotator cuff to
injury, especially from the rapid accelerations and decelerations
inherent to most sports and even some activities of daily living.
anatomy and biomechanics, particularly those of the rotator cuff (RC),
endow the glenohumeral joint with dynamic and static stability
throughout a substantial range of motion. The interconnected
supraspinatus, infraspinatus, teres minor, and subscapularis
musculotendinous complexes constitute the rotator cuff and act as the
shoulder’s primary functional unit. Because of the rotator cuff’s
crucial role, RC pathology may lead to considerable limitations in daily
routine, work, and leisure/sporting activities.
magnetic resonance imaging (MRI) improves the sensitivity and
specificity of diagnosing RC disorders, reduces unnecessary arthroscopic
procedures, and provides important clinical information to guide
patient management. This review will cover recent literature regarding
RC anatomy and the clinical presentation, evaluation, and management of
RC disease. We will discuss new observations about the strengths,
inherent blind spots, and diagnostic effectiveness of shoulder MRI, and
then outline the classification of rotator cuff MRI findings and their
impact on patient management. Finally, we will present an effective
search pattern approach to evaluate the rotator cuff on shoulder MRI
Knowledge of the RC
tendinous insertions onto the proximal humerus, an area known as the
rotator cuff footprint, makes it easier to determine the extent and
location of abnormality. Much has been written recently about the
anatomy of distal RC tendons as they interdigitate to insert upon the 3
facets of the greater tuberosity (superior, middle, and inferior),
although their location and insertion appear somewhat more arbitrary by
MR imaging. Standard landmarks and techniques used in MRI to demarcate
the tendons will be elaborated upon later.
muscle arises from the posterior aspect of the scapula, just above the
scapular spine, and courses horizontally and anteriorly at the level of
the acromioclavicular joint, a good landmark for its musculotendinous
junction. The subacromial-subdeltoid bursa, which usually contains
minimal fluid, if any, drapes over the supraspinatus muscle and tendon
and lies just beneath the acromion. While most anatomy laboratories
still teach that the supraspinatus has a broad footprint, more recent
anatomic and orthopedic literature suggests that it has a relatively
small triangular footprint on the superior facet of the greater
tuberosity.1,2 Importantly, the larger anterior portion of the supraspinatus muscle pulls a smaller cross-sectional area of anterior tendon,3 predisposing the anterior articular fibers to more strain and subsequent tear propagation.4-6
infraspinatus muscle arises from the posterior aspect of the scapula,
below the scapular spine. It then courses laterally, with the anterior
border of the infraspinatus tendon insertion overlapping the posterior
border of the supraspinatus tendon, to attach to the entire middle facet
interdigitating with the supraspinatus tendon at the posterior aspect
of the superior facet.2 The teres minor muscle, elongated in
morphology, arises from the middle portion of the lateral scapular
border and dense fascia of the infraspinatus to insert on the inferior
facet of the greater tuberosity. The large, triangular subscapularis
muscle arises from the anterior surface of the scapula and courses
laterally under the coracoid, with its musculotendinous junction at the
level of the glenoid. This muscle’s attachment to the lesser tuberosity
is comma shaped, with a broad proximal and tapering distal footprint.7,8
The subscapularis fibers extend over the bicipital groove, and the
superior fibers of the subscapularis tendon interdigitate with the
anterior fibers of the supraspinatus tendon over the superior facet of
the greater tuberosity.9
Demographics of rotator cuff pathology
pain is extremely common with reports that approximately half the U.S.
population experiences at least one episode of shoulder pain annually.10
The prevalence of shoulder pain substantially increases with age, and
the most common musculoskeletal complaint in patients >65 is shoulder
pain.11 As rotator cuff tears are often asymptomatic, their
true prevalence remains unknown and reports vary widely; the aptly
titled “Dead Men and Radiologists Don’t Lie” study reports a total
prevalence of RC tears in their cadaveric data group of 30.3% (11.75%
had full thickness tears; 18.49%, partial thickness tears), with the
caveat that most of the cadavers, with a mean age of 70.1 years in that
study, are older than the average patient.12 Yamamoto et al
screened 1366 shoulders, regardless of the presence or absence of
symptoms, and found RC tears in 20.7%; their patients ranged from 22 to
85 years with a mean of 57.9 years. Their analysis also suggested risk
factors for RC tears: a history of trauma, dominant arm, and older age.13
A high correlation between the onset of RC tears and increasing age has
also been reported in several other studies — in one, 50% of patients
>66 years that presented with a painful RC tear also had a rotator
cuff tear in their contralateral, asymptomatic shoulder.14 Likewise, Fehringer et al found full thickness RC tears in 22% of asymptomatic patients ≥65 years.15
In younger asymptomatic adults, the prevalence of tears is expectedly
lower: 5% and 11% in the fourth and fifth decades, respectively. More
surprising, however, are prevalences of 50% in the seventh decade and
80% in the 9th and 10th decades.16 These studies confirm that
RC tears are extremely common, especially in the elderly, and that it
is important to remember that their presence does not always impute pain
or clinically significant loss of function.17
Pathogenesis of RC pathology
the true pathogenesis of rotator cuff tears remains unclear, mechanisms
of RC degeneration are broadly divided into extrinsic and intrinsic
factors. In reality, RC tears are probably a multifactorial byproduct of
the interaction of intrinsic and extrinsic causes.18 In
1934, Codman espoused the “intrinsic” theory that age-related tendon
damage compounded by chronic microtrauma results in partial thickness
tears, which usually then progress to full thickness tears.19
An “extrinsic” cause was first suggested in 1972, when Neer proposed
that RC tears were secondary to subacromial impingement and, therefore,
best treated with anterior acromioplasty.20 It was
traditionally taught that hypovascularity within the critical zone
located 10 to 15 mm proximal to the supraspinatus insertion was a key
component of RC tears.21,22 More recent research conclusively demonstrated that no significant hypovascular zone exists.23-25
Moreover, Matthews and coworkers found that small RC tears showed
increased fibroblast cellularity and blood vessel proliferation, which
gave them greater potential to heal.26 Additional studies
demonstrate that as tear size increases the healing response fails,
cytokines upregulate, and vascularity decreases, eventually resulting in
hypoxic damage and apoptosis.27-29 These novel findings imply the benefit of early rehabilitation and/or surgical management before tears progress.
Clinical presentation, evaluation, and management
with symptomatic rotator cuff tears usually present with shoulder pain,
dysfunction, or both. Classic clinical teaching suggests that these
symptoms are more significant in patients with subacromial bursitis
and/or partial thickness RC tears compared to those with full thickness
tears. Fukuda further reports that bursal-sided tears are more painful
than articular-sided tears.30 However, a more recent study by
Brownlow et al relates that no statistical difference exists, and that
neither pain nor stiffness can reliably differentiate partial and
Clinical evaluation is the
first step toward diagnosing RC disease. Clinicians often rely upon a
battery of tests to evaluate and classify patients appropriately. A
meta-analysis suggests that the diagnostic accuracy of orthopedic
shoulder exams is overestimated, and that these exams are only rarely
useful to differentiate RC tears. While some shoulder examination tests
had high sensitivities and others had high specificities, no single test
had both a high specificity and a high sensitivity.32
Further, the lack of precise techniques and subjective interpretation of
these exams leads to substantial interobserver variability.33
of partial and full thickness RC tears remains largely controversial.
While nonoperative rehabilitation is successful in certain patient
subgroups — predominately elderly patients with a sedentary lifestyle —
early surgical repair is indicated in other patients, usually younger
and more active individuals.34 Despite good to excellent
results of surgical repair in a high percentage of patients, re-rupture
of the cuff is known to occur 20% to 65% of the time.35,36
Much of the management controversy relates, in part, to diverse patient
populations, varied surgical techniques, and a paucity of
well-controlled comparative data. MRI plays a significant role in
evaluating the stage and prognosis of RC disease: tear size, tendon
retraction, and the extent of muscle atrophy, each of which negatively
impacts the functional outcome. The clinical function and MRI appearance
of RC tears deteriorate with time.30,37 Partial thickness
tears of the anterior supraspinatus fibers increase strain upon the
remaining supraspinatus fibers and intact infraspinatus tendon, leading
to tear propagation and potentially impacting the decision to operate
sooner as opposed to waiting.5 The findings of Goutallier et
al similarly support that increased wait times lead to increased fatty
degeneration of the torn rotator cuff muscle.38,39 Along
these lines, Shen et al demonstrated a significant positive correlation
between supraspinatus fatty atrophy preoperatively with postsurgical
functional outcomes.40 The article by Gladstone et al
similarly confirmed that muscle atrophy and fatty infiltration played a
significant role in functional outcome after repair. They added that
tear size appears to have the most influential effect on repair
integrity.41 Fatty degeneration of the RC is closely
associated with tear size and location. In particular, integrity of the
anterior supraspinatus tendon seems to be the most important variable
related to fatty degeneration.42 A natural history of fatty
infiltration relative to onset of shoulder symptoms was suggested by
Melis et al, with moderate fatty infiltration at 3 years and severe
fatty infiltration at 5 years.39,43,44
though shoulder radiographs in acute rotator cuff tears are usually
normal, they remain the appropriate first line of imaging to evaluate
osseous structures and exclude common fractures and dislocations.45-47
While multiple radiographic maneuvers and techniques have been
suggested to help diagnose RC tears, and ultrasound in the hands of an
experienced investigator has comparable accuracy,47-49 MRI
remains the study of choice for evaluating the shoulder. MRI can
evaluate the size and shape of the tear, the amount of tendon
retraction, the prominence of muscle atrophy, and the quality of
remaining RC tendon. In addition, it can accurately evaluate other
potential causes of shoulder pain that may mimic RC tears.48
MRI can detect full thickness RC tears with high sensitivity and
specificity, but MRI diagnosis of partial thickness tears is less
sensitive and accurate. A large meta-analysis compiled in 2009 used a
surgical reference standard and found pooled MRI sensitivity and
specificity for full thickness tears of 92.1% and 92.9%; for partial
thickness tears of 63.6% and 91.7%; and for full or partial thickness
tears of 87.0% and 81.7%, respectively.50 However, often
cited statistics on the diagnostic effectiveness of MRI remain skewed by
older protocols and outdated data that lack currently available spatial
resolution; some of these even lack fat-suppression or T2-weighted
images.51 MRI of the RC at 3.0 Tesla appears promising. In
2006, Magee reported sensitivity and specificity of 98% and 96%,
respectively, for full thickness supraspinatus tears and, even more
impressive, of 89.5% and 90%, respectively, for partial thickness
supraspinatus tears.52 The diagnostic accuracy of shoulder MRI improves with experience and training.53, 54
the often-utilized gold standard of rotator cuff disease diagnosis —
shoulder arthroscopy — is not without similar flaws. With the exception
of distinguishing partial- from full-thickness RC tears and identifying
the side of partial thickness tears (articular versus bursal), RC
classification systems have little interobserver agreement even among
experienced shoulder surgeons.55
Classification of rotator cuff tears
Numerous rotator-cuff-tear classification systems have been proposed.56-60
Though several are highly accurate, they are similarly complex and lack
intraobserver and interobserver agreement. With an increasing emphasis
on evidence-based medicine, MRI descriptions of RC tears need to be
accurate, simple, and precise with high interobserver agreement.61 Common pathology of the RC tendons includes full thickness tears, partial thickness tears, and tendinosis.
Full thickness tears
abnormality of the rotator cuff is considered a full thickness tear if
it results in a connection between the articular and bursal surfaces of
the cuff tendon. The most specific sign of a full thickness RC tear is
visualization of a complete defect in the tendon, extending from the
articular surface completely through to the bursal surface. This defect
is usually fluid signal intensity as it is filled with fluid, organizing
granulation tissue, myofibroblastic proliferation, chondroid metaplasia
and/or hemorrhage.26,62 Fortunately, this appearance of full thickness tears is also the most common, seen approximately 87% of the time.63
Less commonly, full thickness defects contain intermediate T2 signal
intensity, probably related to chronic scarring or volume averaging with
adjacent histopathologic changes, such as scarring or mucoid
degeneration.64 Less classic findings are more frequent when
the defects are small, given the increased potential for volume
averaging. Secondary signs of a full thickness RC tear — fluid in the
subacromial-subdeltoid bursa, muscle atrophy, intramuscular cysts,
superior humeral migration, and retraction of the musculotendinous
junction — used to be more heavily relied upon prior to
higher-resolution MR capabilities and the routine use of fat
suppression.63,65-67 While these secondary findings in
isolation never confirm a full thickness tear, they should prompt a
close second look. It’s worth mentioning that literature has
demonstrated each of these secondary findings with partial thickness
tears and even in patients without a tendon defect.68-71 To
adequately detail full thickness RC tears, two descriptors should be
used: the anteroposterior extent of the tear and the amount of medial
tendon retraction. Precise measurements for the anteroposterior extent
of full thickness tears have been abandoned because of subjective
variability and lack of reproducibility. Descriptive categories are
instead used to group the anteroposterior extent of full thickness
tears: small (<1 cm), medium (1-3 cm), large (3-5 cm), and massive
(>5 cm). The amount of tendon retraction (Figure 1) is best evaluated
on coronal oblique images by describing the location of the torn and
retracted tendon in one of 3 ways: near the humeral insertion, at the
level of the humeral dome, or at the level of the glenoid.59
The final component of describing a full thickness tear is evaluating
the RC muscles for volume atrophy or fatty infiltration, which, as
described previously, significantly impact functional outcome after
Partial thickness tears
thickness tears involve a spectrum of findings and are broadly
classified into 3 different types according to the portion of the tendon
that is abnormal: articular-sided tears, bursal-sided tears, and
Articular-sided tears (Figure 2) are by far
the most common, involving the tendon fibers adjacent to the humeral
head. Bursal-sided tears (Figure 3) are significantly less common — 2.9%
of partial thickness tears in one series72 — and involve the
more superiorly located fibers that abut the subacromial-subdeltoid
bursa. The combination of fluid, granulation tissue, and blood within
partial thickness tears causes their hyperintense T2 signal
characteristics, similar to those of full thickness tears, but without
full thickness involvement of the tendon.73 For example, if
intact bursal-sided fibers are identified overlying discontinuous
articular-sided fibers, the diagnosis of an articular-sided partial
thickness tear has been made. Beyond the location of the partial
thickness tear, describing the extent of the tear is also important.
Ruotolo et al showed that the mean thickness of the supraspinatus tendon
ranges from 11.6 mm (anteriorly) to 12.1 mm (midtendon).74
Exact measurements are difficult to recreate precisely, so descriptive
terms work best, combined with an awareness of their clinical
implication. Small tears (<3 mm deep) and medium tears (3-6 mm deep)
involve <50% of the tendon thickness, while large partial thickness
tears (>6 mm deep) involve >50% of the tendon fibers (Figure 4).57
Treatment of articular-sided, partial thickness tendon tears involving
<50% of the fibers usually involves surgical debridement. In
contrast, most authors recommend surgical repair of articular-sided
tears involving 50% or more of the tendon thickness.75, 76
thickness, articular-sided RC tears involving the insertional fibers of
the anterior-most aspect of the supraspinatus (Figure 5), sometimes
referred to as rim-rents, are very common tears, but they are easily
overlooked.72 Becoming more aware of these tears, their
location and their frequency should lead to a focused evaluation for
these defects. Specific techniques to look for rim-rents will be
discussed in the search pattern section below.
Interstitial tears may represent up to 33% of partial thickness tears77 and are thought to represent shearing forces within a degenerated tendon.78
Interstitial tears (Figure 6), also known as intrasubstance tears or
intramuscular cysts, can occur in isolation within the tendon without
articular- or bursal-sided extension, or they can also occur in
combination with either articular- or bursal-sided partial thickness
tears. Intramuscular cysts, towards the larger, more elliptical end of
the interstitial tear spectrum, were seen in 0.3% of a large
retrospective series of shoulder MR examinations, and are almost always
(96-100%) associated with an RC tear.66,79,80 Though
management of isolated interstitial tears remains controversial, they
should be reported since they are not visible to the arthroscopist.
RC tendons, composed primarily of collagen bundles, are characterized
by uniform hypointense signal intensity on all pulse sequences. Though
in the past the term “tendonitis” had been used to refer to a variety of
shoulder problems, degenerative and traumatic changes of the RC tendons
do not always include inflammation, so tendinosis or tendinopathy are
the preferred terms. Histological changes of RC tendons, most commonly
mucoid degeneration and fibrocartilaginous metaplasia, appear as
moderately increased focal irregular or diffuse intermediate
intrasubstance signal intensity on T1- and T2-weighted images.64
This altered MRI signal intensity does not rise to the same T2 signal
intensity as fluid and is usually more globular in appearance and less
linear than signal abnormalities seen with RC tears. The tendon may be
normal in caliber or demonstrate diffuse or focal thickening (Figure 7).81
Sein et al showed high intraobserver reliability, with an intraclass
correlation of 0.85, in grading tendinosis as mild, moderate, or severe.82
In practice, it can occasionally be difficult to distinguish between
severe tendinosis and a partial thickness tear; sometimes both
possibilities must be considered.
Humeral head cysts
head “cysts,” foci of fluid signal intensity in the bone marrow of the
greater tuberosity near the RC insertions, are common on shoulder MRI,
seen in 70% of symptomatic patients and 24% of asymptomatic volunteers.51, 83
They occur most frequently within the posterior aspect of the greater
tuberosity (56%-90%), followed by the anterior aspect of the greater
tuberosity (20%-22%), and least often within the lesser tuberosity
(15%).83, 84 Cysts within the posterior aspect of the greater
tuberosity show no association to RC abnormalities, and are thought to
represent normal variant pseudocysts, since they contain no synovial
lining and are filled with thick connective tissue.83-85
While one article suggested no definite association between RC tears and
cysts within the anterior aspect of the greater tuberosity,83
most studies endorse an association with RC disease. Sano et al in 1998
indicated that RC tears were always present when humeral head cysts
were present in the superior facet or the anterior half of the middle
facet.86 More recently, Fritz et al reported that cysts
within the anterior aspect of the greater tuberosity (Figure 8) have a
high positive predictive value (94%) for RC disease; further, anterior
greater tuberosity cysts were rarely, only 2.5% of the time, seen with
normal rotator cuffs.84 Cysts within the lesser tuberosity,
though less common, almost always correlate with tears of the RC,
particularly the overlying subscapularis or supraspinatus tendons.86,87
Humeral head “cysts” can simulate small insertional RC tears, and
should therefore be evaluated on orthogonal views, which usually better
reveal that the fluid-signal intensity is actually subcortical and not
within the distal RC tendon.
changes after RC tears are defined by 2 separate parameters: volume
atrophy and fatty infiltration. Since volume atrophy and fatty
infiltration occur highly asymmetrically — especially in the
supraspinatus due to the disproportionate biomechanical changes when
anterior tendon fibers are torn — both qualifiers should always be
evaluated and mentioned.88 Goutallier, using CT scans, proposed the first classification scheme for volume atrophy and fatty infiltration of RC muscles.89
Warner et al further expanded fatty atrophy evaluation using sagittal
oblique T1-weighted MR images just medial to the coracoid. This volume
atrophy classification scheme uses the tangent line, drawn horizontally
between the superior edge of the coracoid and the scapular spine, and
another line drawn vertically from the scapular spine to the inferior
scapular tip. Muscle bellies that remain convex beyond these lines are
graded as normal; those that are even with the lines are called mild
atrophy; muscle concave below the line is moderately atrophied; muscle
that is barely visible is severely atrophied (Figure 9).90
Fuchs et al modified Goutallier’s original classification scheme of
fatty infiltration to MRI – describing the proportion of fatty streaks
and replacement relative to muscle.91 Their original staging
has been further qualified and descriptive modifiers are now usually
used to describe fatty infiltration: no fatty deposits is described as
no fatty infiltration; a few fatty streaks, as minimal fatty
infiltration; some fatty infiltration, though still with more muscle
than fat, as mild fatty infiltration; a roughly equal proportion of
muscle and fatty infiltration as moderate fatty infiltration; and a
predominance of fatty infiltration, as advanced fatty infiltration.
most radiologic exams, shoulder MR imaging is best evaluated with a
routine search pattern that pays specific attention to the usual
locations of pathology and relies upon the specific strengths of each
obtained sequence. Our standard shoulder MRI protocol contains 5 pulse
sequences: sagittal oblique T1-weighted and fast spin echo (FSE)
T2-weighted with fat saturation, axial FSE proton density and FSE
T2-weighted with fat saturation, and coronal oblique FSE T2-weighted
with fat saturation.
Rotator cuff muscles
component of MRI RC evaluation involves the muscle bellies on the
T1-weighted and T2-weighted sagittal oblique sequences. As described
previously, the presence of fatty infiltration or muscle volume atrophy
is best evaluated on the T1-weighted sagittal oblique images. Sagittal
oblique T2-weighted images are used to carefully evaluate the muscle
bellies for often subtle or asymmetric edema. Muscular edema often
represents an acute injury, such as muscle strain, particularly within
the clinical context of an acute injury and when correlating findings of
an acute RC tear are present. Neurogenic abnormalities can also cause
muscle edema, if detected early, and muscle atrophy, if more chronic.
They are usually identified by the distinct combination of muscle
bellies involved: Suprascapular nerve entrapment at the suprascapular
notch affects the supraspinatus and infraspinatus muscles; suprascapular
nerve entrapment at the level of the spinoglenoid notch (distal to
supraspinatus motor innervation) affects only the infraspinatus muscle;
quadrilateral space syndrome (compression of the axillary nerve in the
quadrilateral space) usually affects just the teres minor muscle; and
Parsonage-Turner Syndrome, an acute brachial neuritis, can involve
single or multiple nerve distributions (Figure 10).
Rotator cuff tendons
knowledge of RC anatomy, MRI relies upon landmarks to delineate the
location of the RC tendons. The precise transition between the
supraspinatus and infraspinatus is difficult to distinguish by MRI given
their interdigitating fibers. When the patient is correctly positioned
with the arm neutral or slightly externally rotated, the 12 o’clock
humeral head position on sagittal oblique sequences is used to
distinguish where the supraspinatus and infraspinatus insert on the
greater tuberosity — supraspinatus fibers are anterior (10 and 11
o’clock), supraspinatus and infraspinatus fibers blend near 12 o’clock,
and infraspinatus fibers posteriorly occupy the 1 and 2 o’clock
positions. Internal rotation of the arm produces overlap of the
supraspinatus and infraspinatus tendons, making evaluation of the RC
difficult.92 With internal rotation or extreme external
rotation, the humeral head clock positions are suboptimal for
distinguishing the tendon insertions.
Having evaluated the RC
muscle bellies, and with a familiarity of how to distinguish the RC
footprints, the search pattern next individually evaluates each of the 4
RC tendons. Most PACS display monitors allow similarly oriented
sequences to be linked and orthogonal sequences to be cross-referenced.
Beginning at the medial aspect of the sagittal oblique T2-weighted
images, the supraspinatus muscle is first located by its anatomic
position on the scapula. Proceeding laterally, sagittal oblique images
are incrementally examined. When abnormalities are seen or suspected in
the supraspinatus tendon on sagittal oblique images, they are
cross-referenced on coronal oblique images. The integrity of the
supraspinatus tendon is again completely evaluated by the coronal
oblique sequence. The extra-articular long biceps tendon is located on
the anterior coronal oblique images, and proceeding posteriorly, the
anterior-most fibers of the supraspinatus tendon are evaluated. Again,
any signal abnormality detected within the supraspinatus tendon on
coronal oblique images is cross-referenced and evaluated on the sagittal
oblique images. Abnormal supraspinatus findings — tendinosis or partial
or full thickness tears — are categorized and described, as mentioned
earlier. A similar 2-plane approach is used to confirm and evaluate the
status of each remaining tendon, usually proceeding from the
supraspinatus to the infraspinatus, then to the subscapularis, and
finally, to the teres minor, which is almost never torn.
partial thickness tears involving the far anterior supraspinatus fibers
have a high prevalence, are often difficult to visualize (particularly
when the arm is internally rotated), and as a result are frequently
missed,72 the last step involves an intentional search for
rim-rents. Because they are often difficult to locate on sagittal
oblique images, we rely instead upon coronal oblique and axial
sequences. The extra-articular long head of the biceps tendon is
identified on coronal oblique images; the anterior-most fibers of the
supraspinatus are located just posterior to that point. These anterior
fibers are also cross-referenced on axial images as a precautionary
Our understanding of rotator
cuff pathogenesis and the optimal management of RC pathology is
evolving. Shoulder MRI is a valuable tool in evaluating the patient with
a painful shoulder, as it accurately depicts RC tendon pathology and
any associated muscle abnormalities. In addition, shoulder MRI may
reveal concurrent or alternative diagnoses, beyond the scope of this
article, which can mimic RC disease clinically.
- Mochizuki T, Sugaya H, Uomizu M, et al. Humeral insertion of the
supraspinatus and infraspinatus. New anatomical findings regarding the
footprint of the rotator cuff. Surgical technique. J Bone Joint Surg Am. 2009;91 Suppl 2 Pt 1:1-7.
- Mochizuki T, Sugaya H, Uomizu M, et al. Humeral insertion of the
supraspinatus and infraspinatus. New anatomical findings regarding the
footprint of the rotator cuff. J Bone Joint Surg Am. 2008;90:962-969.
- DeFranco MJ, Cole BJ. Current perspectives on rotator cuff anatomy. Arthroscopy. 2009;25: 305-320.
- Andarawis-Puri N, Kuntz AF, Kim SY, Soslowsky LJ. Effect of anterior
supraspinatus tendon partial-thickness tears on infraspinatus tendon
strain through a range of joint rotation angles. J Shoulder Elbow Surg. 2010;19:617-623.
- Andarawis-Puri N, Ricchetti ET, Soslowsky LJ. Rotator cuff tendon strain correlates with tear propagation. J Biomech. 2009;42:158-163.
- Reilly P, Amis AA, Wallace AL, Emery RJ. Supraspinatus tears: Propagation and strain alteration. J Shoulder Elbow Surg. 2003;12:134-138.
- Ide J, Tokiyoshi A, Hirose J, Mizuta H. An anatomic study of the
subscapularis insertion to the humerus: The subscapularis footprint. Arthroscopy. 2008;24:749-753.
- Morag Y, Jamadar DA, Miller B, et al. The subscapularis: Anatomy, injury, and imaging. Skeletal Radiol. 2011;40:255-269.
- Boon JM, de Beer MA, Botha D, et al. The anatomy of the subscapularis tendon insertion as applied to rotator cuff repair. J Shoulder Elbow Surg. 2004;13:165-169.
- Brox JI. Regional musculoskeletal conditions: Shoulder pain. Best Pract Res Clin Rheumatol. 2003;17:33-56.
- Taylor W. Musculoskeletal pain in the adult New Zealand population: Prevalence and impact. N Z Med J. 2005;118:U1629.
- Reilly P, Macleod I, Macfarlane R, et al. Dead men and radiologists
don’t lie: A review of cadaveric and radiological studies of rotator
cuff tear prevalence. Ann R Coll Surg Engl. 2006;88:116-121.
- Yamamoto A, Takagishi K, Osawa T, et al. Prevalence and risk factors of a rotator cuff tear in the general population. J Shoulder Elbow Surg. 2010;19:116-120.
- Yamaguchi K, Ditsios K, Middleton WD, et al. The demographic and
morphological features of rotator cuff disease. A comparison of
asymptomatic and symptomatic shoulders. J Bone Joint Surg Am. 2006;88:1699-1704.
- Fehringer EV, Sun J, Van Oeveren LS, et al. Full-thickness rotator
cuff tear prevalence and correlation with function and co-morbidities in
patients sixty-five years and older. J Shoulder Elbow Surg. 2008;17:881-885.
- Milgrom C, Schaffler M, Gilbert S, van Holsbeeck M. Rotator-cuff
changes in asymptomatic adults. The effect of age, hand dominance and
gender. J Bone Joint Surg Br. 1995;77:296-298.
- Keener JD, Steger-May K, Stobbs G, Yamaguchi K. Asymptomatic rotator
cuff tears: Patient demographics and baseline shoulder function. J Shoulder Elbow Surg. 2010;19:1191-1198.
- Abate M, Silbernagel KG, Siljeholm C, et al. Pathogenesis of tendinopathies: Inflammation or degeneration? Arthritis Res Ther. 2009;11:235.
- Codman EA. The shoulder: Rupture of the supraspinatus tendon and
other lesions in or about the subacromial bursa. Boston, MA: Thomas Todd
- Neer CS, 2nd. Anterior acromioplasty for the chronic impingement syndrome in the shoulder: A preliminary report. J Bone Joint Surg Am. 1972;54:41-50.
- Codman EA, Akerson IB. The pathology associated with rupture of the supraspinatus tendon. Ann Surg. 1931;93:348-359.
- Lohr JF, Uhthoff HK. The microvascular pattern of the supraspinatus tendon. Clin Orthop Relat Res. 1990:35-38.
- Moseley HF, Goldie I. The arterial pattern of the rotator cuff of the shoulder. J Bone Joint Surg Br. 1963;45:780-789.
- Brooks CH, Revell WJ, Heatley FW. A quantitative histological study of the vascularity of the rotator cuff tendon. J Bone Joint Surg Br. 1992;74:151-153.
- Lewis JS, Raza SA, Pilcher J, et al. The prevalence of
neovascularity in patients clinically diagnosed with rotator cuff
tendinopathy. BMC Musculoskelet Disord. 2009;10:163.
- Matthews TJ, Hand GC, Rees JL, et al. Pathology of the torn rotator
cuff tendon. Reduction in potential for repair as tear size increases. J Bone Joint Surg Br. 2006;88:489-495.
- Hegedus EJ, Cook C, Brennan M, et al. Vascularity and tendon
pathology in the rotator cuff: A review of literature and implications
for rehabilitation and surgery. Br J Sports Med. 2010;44:838-847.
- Millar NL, Wei AQ, Molloy TJ, et al. Cytokines and apoptosis in supraspinatus tendinopathy. J Bone Joint Surg Br. 2009;91:417-424.
- Benson RT, McDonnell SM, Knowles HJ, et al. Tendinopathy and tears
of the rotator cuff are associated with hypoxia and apoptosis. J Bone Joint Surg Br. 2010;92:448-453.
- Fukuda H. Partial-thickness rotator cuff tears: A modern view on Codman’s classic. J Shoulder Elbow Surg. 2000;9:163-168.
- Brownlow HC, Smith C, Corner T, et al. Pain and stiffness in partial-thickness rotator cuff tears. Am J Orthop. 2009;38:338-340.
- Hegedus EJ, Goode A, Campbell S, et al. Physical examination tests
of the shoulder: A systematic review with meta-analysis of individual
tests. Br J Sports Med. 2008;42:80-92; discussion 92.
- Beaudreuil J, Nizard R, Thomas T, et al. Contribution of clinical
tests to the diagnosis of rotator cuff disease: A systematic literature
review. Joint Bone Spine. 2009;76:15-19.
- Williams GR, Jr., Rockwood CA, Jr., Bigliani LU, et al. Rotator cuff tears: Why do we repair them? J Bone Joint Surg Am. 2004;86-A:2764-2776.
- Galatz LM, Griggs S, Cameron BD, Iannotti JP. Prospective
longitudinal analysis of postoperative shoulder function: A ten-year
follow-up study of full-thickness rotator cuff tears. J Bone Joint Surg Am. 2001;83-A:1052-1056.
- Ellman H, Kay SP, Wirth M. Arthroscopic treatment of full-thickness rotator cuff tears: 2- to 7-year follow-up study. Arthroscopy. 1993;9:195-200.
- Fukuda H. The management of partial-thickness tears of the rotator cuff. J Bone Joint Surg Br. 2003;85:3-11.
- Goutallier D, Postel JM, Lavau L, Bernageau J. Impact of fatty
degeneration of the suparspinatus and infraspinatus msucles on the
prognosis of surgical repair of the rotator cuff [in French] Rev Chir Orthop Reparatrice Appar Mot. 1999;85:668-676.
- Melis B, Nemoz C, Walch G. Muscle fatty infiltration in rotator cuff tears: Descriptive analysis of 1688 cases. Orthop Traumatol Surg Res. 2009;95:319-324.
- Shen PH, Lien SB, Shen HC, et al. Long-term functional outcomes
after repair of rotator cuff tears correlated with atrophy of the
supraspinatus muscles on magnetic resonance images. J Shoulder Elbow Surg. 2008;17:1S-7S.
- Gladstone JN, Bishop JY, Lo IK, Flatow EL. Fatty infiltration and
atrophy of the rotator cuff do not improve after rotator cuff repair and
correlate with poor functional outcome. Am J Sports Med. 2007;35:719-728.
- Kim HM, Dahiya N, Teefey SA, et al. Relationship of tear size and location to fatty degeneration of the rotator cuff. J Bone Joint Surg Am. 2010;92:829-839.
- Melis B, DeFranco MJ, Chuinard C, Walch G. Natural history of fatty
infiltration and atrophy of the supraspinatus muscle in rotator cuff
tears. Clin Orthop Relat Res. 2010;468:1498-1505.
- Melis B, Wall B, Walch G. Natural history of infraspinatus fatty infiltration in rotator cuff tears. J Shoulder Elbow Surg. 2010;19:757-763.
- Bloom RA. The active abduction view: A new maneuvre in the diagnosis of rotator cuff tears. Skeletal Radiol. 1991;20:255-258.
- Moosikasuwan JB, Miller TT, Burke BJ. Rotator cuff tears: Clinical, radiographic, and US findings. Radiographics. 2005;25:1591-1607.
- Goud A, Segal D, Hedayati P, et al. Radiographic evaluation of the shoulder. Eur J Radiol. 2008;68:2-15.
- Bryant L, Shnier R, Bryant C, Murrell GA. A comparison of clinical
estimation, ultrasonography, magnetic resonance imaging, and arthroscopy
in determining the size of rotator cuff tears. J Shoulder Elbow Surg. 2002;11:219-224.
- Rutten MJ, Jager GJ, Kiemeney LA. Ultrasound detection of rotator
cuff tears: Observer agreement related to increasing experience. AJR Am J Roentgenol. 2010;195:W440-446.
- de Jesus JO, Parker L, Frangos AJ, Nazarian LN. Accuracy of MRI, MR
arthrography, and ultrasound in the diagnosis of rotator cuff tears: a
meta-analysis. AJR Am J Roentgenol. 2009;192:1701-1707.
- Magee T, Shapiro M, Williams D. Comparison of high-field-strength versus low-field-strength MRI of the shoulder. AJR Am J Roentgenol. 2003;181:1211-1215.
- Magee T, Williams D. 3.0-T MRI of the supraspinatus tendon. AJR Am J Roentgenol. 2006;187: 881-886.
- Arekapudi SR, Jamadar DA, Caoili EM, et al. MRI interpretation proficiency of musculoskeletal fellows in training. Acad Radiol. 2009;16:380-385.
- Theodoropoulos JS, Andreisek G, Harvey EJ, Wolin P. Magnetic
resonance imaging and magnetic resonance arthrography of the shoulder:
Dependence on the level of training of the performing radiologist for
diagnostic accuracy. Skeletal Radiol. 2010;39:661-667.
- Kuhn JE, Dunn WR, Ma B, et al. Interobserver agreement in the classification of rotator cuff tears. Am J Sports Med. 2007;35:437-441.
- DeOrio JK, Cofield RH. Results of a second attempt at surgical repair of a failed initial rotator-cuff repair. J Bone Joint Surg Am. 1984;66:563-567.
- Ellman H. Diagnosis and treatment of incomplete rotator cuff tears. Clin Orthop Relat Res. 1990:64-74.
- Harryman DT, Mack LA, Wang KY, et al. Repairs of the rotator cuff.
Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am. 1991;73:982-989.
- Patte D. Classification of rotator cuff lesions. Clin Orthop Relat Res. 1990:81-86.
- Wolfgang GL. Surgical repair of tears of the rotator cuff of the shoulder. Factors influencing the result. J Bone Joint Surg Am. 1974;56:14-26.
- Spencer EE, Jr., Dunn WR, Wright RW, et al. Interobserver agreement
in the classification of rotator cuff tears using magnetic resonance
imaging. Am J Sports Med. 2008;36:99-103.
- Longo UG, Franceschi F, Ruzzini L, et al. Light microscopic histology of supraspinatus tendon ruptures. Knee Surg Sports Traumatol Arthrosc. 2007;15:1390-1394.
- Farley TE, Neumann CH, Steinbach LS, et al. Full-thickness tears of
the rotator cuff of the shoulder: Diagnosis with MR imaging. AJR Am J Roentgenol. 1992;158:347-351.
- Buck FM, Grehn H, Hilbe M, et al. Magnetic resonance histologic correlation in rotator cuff tendons. J Magn Reson Imaging. 2010;32:165-172.
- Cvitanic O, Schimandle J, Cruse A, Minter J. The acromioclavicular
joint cyst: Glenohumeral joint communication revealed by MR
arthrography. J Comput Assist Tomogr. 1999;23:141-143.
- Sanders TG, Tirman PF, Feller JF, Genant HK. Association of
intramuscular cysts of the rotator cuff with tears of the rotator cuff:
Magnetic resonance imaging findings and clinical significance. Arthroscopy. 2000;16:230-235.
- Saupe N, Pfirrmann CW, Schmid MR, et al. Association between rotator cuff abnormalities and reduced acromiohumeral distance. AJR Am J Roentgenol. 2006;187:376-382.
- Holt RG, Helms CA, Steinbach L, et al. Magnetic resonance imaging of the shoulder: Rationale and current applications. Skeletal Radiol. 1990;19:5-14.
- Needell SD, Zlatkin MB, Sher JS, et al. MR imaging of the rotator
cuff: Peritendinous and bone abnormalities in an asymptomatic
population. AJR Am J Roentgenol. 1996;166:863-867.
- Schweitzer ME, Magbalon MJ, Frieman BG, et al. Acromioclavicular
joint fluid: Determination of clinical significance with MR imaging. Radiology. 1994;192:205-207.
- Liou JT, Wilson AJ, Totty WG, Brown JJ. The normal shoulder: Common
variations that simulate pathologic conditions at MR imaging. Radiology. 1993;186:435-441.
- Vinson EN, Helms CA, Higgins LD. Rim-rent tear of the rotator cuff: A common and easily overlooked partial tear. AJR Am J Roentgenol. 2007;189:943-946.
- Kjellin I, Ho CP, Cervilla V, et al. Alterations in the
supraspinatus tendon at MR imaging: Correlation with histopathologic
findings in cadavers. Radiology. 1991;181:837-841.
- Ruotolo C, Fow JE, Nottage WM. The supraspinatus footprint: An anatomic study of the supraspinatus insertion. Arthroscopy. 2004;20:246-249.
- Wolff AB, Sethi P, Sutton KM, et al. Partial-thickness rotator cuff tears. J Am Acad Orthop Surg. 2006;14:715-725.
- Finnan RP, Crosby LA. Partial-thickness rotator cuff tears. J Shoulder Elbow Surg. 2010;19:609-616.
- Schaeffeler C, Mueller D, Kirchhoff C, et al. Tears at the rotator
cuff footprint: Prevalence and imaging characteristics in 305 MR
arthrograms of the shoulder. Eur Radiol. 2011;21(7):1477-1484.
- Fukuda H, Hamada K, Nakajima T, Tomonaga A. Pathology and
pathogenesis of the intratendinous tearing of the rotator cuff viewed
from en bloc histologic sections. Clin Orthop Relat Res. 1994:60-67.
- Kassarjian A, Torriani M, Ouellette H, Palmer WE. Intramuscular
rotator cuff cysts: Association with tendon tears on MRI and
arthroscopy. AJR Am J Roentgenol. 2005;185:160-165.
- Manvar AM, Kamireddi A, Bhalani SM, Major NM. Clinical significance
of intramuscular cysts in the rotator cuff and their relationship to
full- and partial-thickness rotator cuff tears. AJR Am J Roentgenol. 2009;192:719-724.
- Kassarjian A, Bencardino JT, Palmer WE. MR imaging of the rotator cuff. Magn Reson Imaging Clin N Am. 2004;12:39-60, vi.
- Sein ML, Walton J, Linklater J, et al. Reliability of MRI assessment of supraspinatus tendinopathy. Br J Sports Med. 2007;41:e9.
- Williams M, Lambert RG, Jhangri GS, et al. Humeral head cysts and rotator cuff tears: An MR arthrographic study. Skeletal Radiol. 2006;35:
- Fritz LB, Ouellette HA, O’Hanley TA, et al. Cystic changes at
supraspinatus and infraspinatus tendon insertion sites: association with
age and rotator cuff disorders in 238 patients. Radiology. 2007;244:239-248.
- Jin W, Ryu KN, Park YK, et al. Cystic lesions in the posterosuperior
portion of the humeral head on MR arthrography: correlations with gross
and histologic findings in cadavers. AJR Am J Roentgenol. 2005;184:1211-1215.
- Sano A, Itoi E, Konno N, et al. Cystic changes of the humeral head on MR imaging. Relation to age and cuff-tears. Acta Orthop Scand. 1998;69:397-400.
- Wissman RD, Kapur S, Akers J, et al. Cysts within and adjacent to
the lesser tuberosity and their association with rotator cuff
abnormalities. AJR Am J Roentgenol. 2009;193:1603-1606.
- Meyer DC, Pirkl C, Pfirrmann CW, et al. Asymmetric atrophy of the supraspinatus muscle following tendon tear. J Orthop Res. 2005;23:254-258.
- Goutallier D, Postel JM, Bernageau J, et al. Fatty muscle
degeneration in cuff ruptures. Pre- and postoperative evaluation by CT
scan. Clin Orthop Relat Res. 1994:78-83.
- Warner JJ, Higgins L, Parsons IM, Dowdy P. Diagnosis and treatment of anterosuperior rotator cuff tears. J Shoulder Elbow Surg. 2001;10:37-46.
- Fuchs B, Weishaupt D, Zanetti M, et al. Fatty degeneration of the
muscles of the rotator cuff: Assessment by computed tomography versus
magnetic resonance imaging. J Shoulder Elbow Surg. 1999;8:599-605.
- Davis SJ, Teresi LM, Bradley WG, et al. Effect of arm rotation on MR imaging of the rotator cuff. Radiology. 1991;181:265-268.