W. Chan,
Teresa
MD
#{149} Murray
MD
K. Dalinka,
J.
#{149} Bruce
Kneeland,
MD
#{149} Alain
MD
Chervrot,
Biceps Tendon Dislocation: Evaluation with MR Imaging’
D
The magnetic resonance (MR) images from six patients with biceps tendon dislocation two in whom
-
-
was surgically proved whom it was suspected spectively evaluated.
and
four
were
The
it
in
retro-
dislocated
tendon can be identified medial to the bicipital groove, best seen on the axial and oblique coronal and sagittal images. Associated abnormalities of the biceps tendon indude thickening (n 3), high signal intensity fluid (n contribute well seen
dude
=
abnormal (n
coracohumeral ruption
(n
=
shape
of the bicipi-
2), disruption ligament (n 4) and thinning =
of the subscapularis praspinatus tendon
tendon, tear (n
Since MR imaging modality of choice
tion
dislocation radiographic
(n 3), and surrounding 4). The factors thought to to dislocation can also be on MR images. These in-
tal groove
of the 6), dis(n 1)
and su4).
is becoming the for the evalua-
ages
derangements, faappearance of bitendon dislocation on MR imis important.
Index
terms:
miliarity
ceps
Tendons,
of shoulder with
the
Shoulder,
injuries,
41.42
MR studies, #{149} Tendons,
41.1214
#{149}
MR studies,
41.1214 Radiology
1991;
179:649-652
‘ From the Department of Radiology, Devon MRI Center, Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia, PA
19104.
Received
November
i2,
1990;
revision
requested December 18; revision received ary 23, 1991; accepted January 29. Address print requests to M.K.D. #{176}RSNA, 1991
of the biceps tendon is an uncommon, frequently unrecognized cause of shoulder pain (1). Although the clinical symptoms may be indicative of an isolated abnormality, they are more commonly associated with other shoulder abnormalities, particularly rotator cuff tears (2). Since the clinical presentation of rotator cuff tear and tendon ISLOCATION
Janure-
can be similar, accurate diagnosis is important difference in surgical man-
given the agement (2). The diagnosis of medial dislocation can be made by means of a demonstration of a medially dislocated biceps tendon sheath at arthrographic examination (3). The increasing use of MR imaging in the evaluation of the painful shoulder has made it easier to recognize this important abnormality. However, to our knowledge, only one case has been reported involving diagnosis of this entity with MR imaging (4). Our experience with six patients and the characteristic MR findings are the subject of this article.
MATERIALS
AND
METHODS
Among 420 shoulder MR examinations performed from January 1988 to September 1990 in our institution, a retrospective review of the MR images showed four patients to have presumed medial dislocation of the biceps tendon. Two additional cases were obtained from outside institutions that submitted studies to our department for consultation. Among these six patients, two had surgical confirmation of the MR imaging finding of biceps dislocation. The images from 10 control subjects with normal MR findings were used for comparison of the biceps tendon diameter, width and depth of the bicipital groove, and medial wall angle of the groove. All MR imaging was performed with a 1.5-T unit (GE Medical Systems, Milwaukee). The surface coils used were either a 5-inch Helmholtz pair or an anterior oval loop coil (Medrad, Pittsburgh). Axial images in four patients were obtained by us-
ing a multiplanar imaging sequence
fast time (TR) of 800 msec, of 15 msec (TR/TE 800/15), a flip angle of 70#{176}, a 14-cm field of view, 4-mm-thick contiguous sections, a 128 X 256 matrix, and two signals averaged. Two patients underwent axial Ti-weighted imaging (600/20). Coronal oblique Ti-weighted imaging (1,000/20) parallel to the supraspinatus muscle was performed with a 14cm field of view, a 3-mm interleaved gap, and two signals averaged. All subjects amderwent coronal oblique proton-densityweighted and T2-weighted imaging (2,500/20, 70) with a 14-16-cm field of view, a 5-mm section thickness with a 1mm gap, and two signals averaged. In some cases, additional sagittal oblique (perpendicular to the supraspinatus musdo) Ti-weighted or T2-weighted images were obtained by using similar parametens. The images were reviewed qualitatively by three
gradient-recalled with a repetition an echo time (TE)
radiologists
in concert
with
regard to the following: (a) location and signal intensity of the biceps tendon, (b) shape of the bicipital groove, (c) presonce of fluid in the joint and tendon sheath, and (d) integrity of the supraspinatus tendon, subscapularis tendon, and adjacent ligamentous structures. In addition, quantitative measurements in these six patients, as well as in the 10 control subjects, were obtained by one of the radiologists (T.W.C.) as follows. The biceps tendon diameter was measured at the widest point of its extracapsular portion. In cases in which the tendon had an ovoid or irregular shape, the length of the greatest transverse dimension and that perpendicular to it were obtained and averaged. The width of the bicipital groove was measured between the superior margin of the lesser and greater tuberosities. The depth of the groove was meastared at the same level. The medial wall angle was measured at the intersection between a line drawn tangential to the superior margins of the greater and lesser tuberosities and a second line tangential to the medial wall of the bicipital groove. These methods are similar to those used with plain radiographs in the study of Cone et a! (5). The normal anatomy of the biceps tendon on MR images is illustrated in Figure 1. 649
MR Findings
of Medial Biceps
Dislocation
of the Long Bicipital
Patient No/Age (y)
High Signal Intensity
Diameter (cm)
1/73 2/61
7 8 8 5 5 5
3/65
4/35’ 5/23 6/55
Shape
Yes Yes Yes No No No
Depth (mm)
8 8 10
5 5 6
8 8
3 5
tuberosity depth and
Table
summarizes
in the
images,
the
contains
six
the
MR
patients.
bicipital
the
On
groove
biceps
axial
normally
tendon
(Fig
ia).
The medially dislocated tendon can be well seen on coronal and axial images (Figs 2, 3). On axial views, the bicipital groove was empty (Fig 3). In one patient, a structure with low signal
intensity,
presumably
an
osteo-
the
the
tendon
region
brum,
was
of the
displaced
anterior
simulating
By following
nial
axial
this
sections,
tear
la-
(Fig
structure
one
can
on se-
differenti-
ate between and a torn the tendon
the displaced tendon labrum. More infeniorly, is located either just me-
dial
lesser
to the
tuberosity
(three
pa-
tients) or in a more medial position between the tuberosity and the glenoid (three patients). In the two patients
in whom
don was
the
4.9 mm difference
subscapulanis
biceps tendon group was of the control
of patients
High don (Fig
signal
was
groove
disposes
wall
55.0#{176}± 16.9#{176}for 64.5#{176}± 9.8#{176} for
For the 650
study
#{149} Radiology
not
the
have
dislocation
angle the the
group,
around
study
the
8.4
displaced
in
-
mm
±
the
supra-
The
coracohumeral
which
was
present
was
The pected tients.
a
ligament,
in all control
absent
in all
six
biceps dislocation clinically in any The patient with tear
sub-
patients.
was not susof the six pathe acute su-
(patient
5) under-
a primary repair of the rotator Persistent pain and limitation of necessitated a subsequent bitenodesis. Patient 4 also undera biceps tenodesis and subsca-
pulanis
tendon
patients
are
uals.
The subin one of in the
The
reattachment.
young,
other
Both
active
‘
b. ,,
.
four
rently undergoing tive therapy.
patients
a trial
and
of the
long
head
arises
The
from
the
of the
scapula.
of the
are
biceps
supraglenoid
The
Figure
1.
MR images
of normal
biceps
ten-
don. (a) Multiplanar gradient-recalled axial image (800/15; flip angle, 70#{176}) shows the biceps tendon as a round, low-signal-intensity structure within the bicipital groove. The tendon of the subscapularis muscle (arrow) is seen sweeping anterior to this as it inserts onto the lesser tuberosity. The transverse ligament is seen as a low-signal-intensity structure bridging the greater and lesser tuberosities (arrowhead). (b) Ti-weighted coronal oblique image (600/20) shows the biceps tendon (black arrow) passing under the fanlike subscapularis tendon (white arrow) as it enters the bicipital groove. The coracohumeral ligament is seen extending from the coracoid process to the lesser tuberosity (arrowhead). (c) Proton-density-weighted sagittal oblique image (2,500/20) shows the biceps (arrowhead) and the supraspinatus (open arrow) and subscapularis (solid arrow) tendons.
cur-
of conserva-
DISCUSSION
group.
c.
individ-
pre-
group
a.
biceps
patients,
other.
(7).
width
the
In two
measured
control
measured
MR
Associated abnormalities of the notator cuff were found in all six patients. Large tears of both the supraspinatus and subscapularis tendons were seen in three patients. These occurred in the absence of recent trauma and were associated with muscle atrophy. A moderate-sized tear of the supraspinatus tendon was present in one patient with a history of acute
went cuff. motion ceps went
ten-
implicated
that
groove
praspinatus
multi-
seen
as a factor
to tendon
medial
is
sequences.
subjects. studies
shallow The
study
within
fluid
jects,
of this the
in three patients with the axial
characteristic
control Previous
± was
biceps tenthickened Figs 2, 3).
gradient-recalled
This the
intensity
was present 3), best seen
planar
diameter 6.3 mm group
in this
small. Qualitatively, the don appeared abnormally in three patients (Table;
identifiable on the axial therefore, not measurable.
0.89 and the depth was 4.8 mm ± 1.1. In the control group, these measurements were 7.9 mm ± 0.74 and 5.9 mm ± 1.4, respectively. Qualitatively, two patients were thought to have an abnormal groove (Fig 5). A large amount of joint fluid was seen in two patients and a moderate amount in one. In all three patients,
trauma.
ten-
± .75. The significance is uncertain, since
number
but no greater tuberosity medial wall angle were,
‘
Tear Thin Tear Tear Normal Tear
spinatus tendon was intact. scapularis tendon was torn these patients and was thin
was intact, the biceps tendon located deep to it (Figs 3b, 4c).
The mean for the patient 1.5 and that
45#{176} Large tear 65#{176} Intact 70#{176} Largetear Intact 30#{176} Acute tear 65#{176} Large tear
joint. to
glenoid
a labral
3a).
Subscapularis Tendon
tendon was also seen. In another patient, fluid was seen around the displaced biceps tendon but not in the
phyte, was identified within the groove on a single section, mimicking the normal tendon. In two patients,
Tendon
Supraspinatus Tendon
Angle
bicipital
RESULTS The
of the Biceps
Groove
Width (mm)
Normal Normal Normal Shallow Shallow Normal
. This patient had a prominent lesser images. The bicipital groove width and
findings
Head
Tendon
intraarticular
tendon tubercie
por-
tion of the biceps tendon runs deep to the coracohumeral ligament, which bridges the interval between the supraspinatus and subscapularis tendons. As the tendon enters the bicipital groove, it lies beneath the thin intertubercular transverse ligament.
June
1991
-----
-
,i
.
....
‘
..
..
4l
c,
.
i#{149}*
#{248}4%
.t.,
#{188}
Figure 2. MR image of patient 1, who had a presumed dislocation of the biceps tendon and large tears of the supraspinatus and subscapularis tendons. Proton-densityweighted oblique coronal image (2,500/20) shows the biceps tendon medial to the groove
a.
b.
Figure 3. MR images from patient (a) Axial multiplanar gradient-recalled
biceps
tendon
(arrow)
ing an anterior
glenoid
cated biceps
(arrow)
2, who image
with a triangular labral
tear.
had
shape
(b) A more
a presumed (800/15;
dislocation
flip
angle,
of the biceps
tendon.
and high signal
70#{176}) shows the thickened intensity within it, mimick-
inferior
shows
section
is deep to the thin subscapularis
that
the medially
dislo-
tendon.
(arrow).
patients, a low-signal-intensity ture, presumably an osteophyte in the
b. Figure 4. Diagrammatic (.),subscapularis tendon
axial
representation
c. of the relationship
between
the biceps
tendon
and transverse ligament (arrowhead). (a) Normal anatomy. (b) With rupture of the transverse ligament and intact subscapularis, the biceps lies medial and anterior to the subscapularis. (c) With degeneration of the insertion of the subscapularis tendon to the lesser tuberosity, the biceps dislocates beneath the subscapularis, which remains attached to the greater tuberosity through the transverse ligament (adapted from reference 6). (*),
and the coracohumeral ligaments are the major restraints preventing dislocation of the biceps tendon (6,8,9). Disruption of these structures is believed to predispose to dislocation. The relationship between the appearance of these structures on axial images is illustrated in Figure 4. In the axial plane, the normal biceps tendon can be seen as a low-signal-intensity, usually ovoid structure in the
Figure 5. Ti-weighted axial image (600/20) of patient 4, who had a shallow bicipital groove and surgically proved dislocation of the biceps tendon. The lesser tuberosity is prominent, but the greater tuberosity was not identifiable on any of the axial images. The biceps tendon (arrow) is medial to the lesser tuberosity. The normal dark fibers of the subscapularis tendon are not seen.
More infeniorly, the tendinous toralis ligament.
Volume
major
it is held in place by expansion of the pec-
muscle, the The subscapularis
179
#{149} Number
3
falciform tendon
bicipital
groove
(Fig
ia).
On
anterior coronal oblique images, it is seen as a linear structure between the greater and lesser tuberosities (Fig ib). The relationship between the biceps tendon and the more superficial coracohumeral ligament and the subscapularis tendon is well demonstrated on anterior coronal oblique images (Fig ib). The medially displaced biceps tendon can be best seen in the axial plane, although coronal oblique and sagittal oblique images are helpful for confirmation. On axial images, one cannot identify the low-signalintensity tendon that is normally situated on the groove. In one of our
groove,
on one
image.
may
next
lie
mimicked
The
strucwith-
the
tendon
displaced
to the
anterior
tendon glenoid
labrum, simulating a labral abnormality. Careful tracing of the course of the tendon on serial axial images would avoid these potential pitfalls. Other abnormalities of the biceps tendon included increased signal intensity, which may be due to tendinitis (10), and thickening of the tendon, which is thought to represent a compensatory response to chronic rotator cuff tear (ii). Radiographic study of the anatomy of the bicipital groove has been performed by using special tangential views (5). The radiographic findings were in agreement with earlier anatomic
studies
strated poses though groove
that a shallow groove predisto tendon dislocation. Alour series is small, a shallow was present in two of our six
(7,8),
patients. Abnormalities
tendon however, our
which
of the
are relatively they were
patients.
Four
demon-
subscapulanis
uncommon; present in five patients
had
of
dis-
ruption of the subscapulanis tendon, three of whom also had large supraspinatus tendon tears. In one patient (patient
2), the
was
thin.
mal
subscapulanis
subscapularis
The tendon
one
tendon
a nor5) had an acute supraspinatus rupture. These findings are similar to those from a previous clinical study, which showed that degeneration of the subscapularis tendon insertion was a common predisposing factor to medial dislocation
The
of the
patient
with
tendon
(patient
biceps
clinical symptoms dislocation are
(6).
of biceps nonspecific Radiology
#{149} 651
and are often masked by those of a concomitant rotator cuff tear. In young, active patients, accurate diagnosis is particularly important, since repair of the rotator cuff tear without biceps tenodesis may not fully relieve the symptoms or restore the complete range of motion (8). The characteristic findings of biceps dislocation are easily seen on
MR images. Because MR imaging is becoming the modality of choice for the noninvasive diagnosis of soft-tissue abnormalities about the shoulder, familiarity this entity tant. U
652
with the appearance of on MR images is impor-
#{149} Radiology
7.
References 1.
2.
DePalma AF. Surgery of the shoulder. 2nd ed. Philadelphia: Lippincott, 1983; 270-272. Burkhead WZ Jr. The biceps tendon. In: Rockwood CA Jr, Matson FA III, eds. The
8.
shoulder.
9.
Philadelphia:
Saunders,
1990;
the tendon
791-832. 3.
Goldman AB. Double contrast shoulder arthrography. In: Freiberger RH, Kaye eds. Arthrography. New York: PrenticeHall, 1979; 165-188.
S, Resnick
Kursunoglu-Brahme
5.
netic resonance imaging of the shoulder. Radiol Clin North Am 1990; 28:941-954. Cone RO, Danzig L, Resnick D, Goldman
6.
AB. The bicipital groove: radiographic, anatomic, and pathologic study. AJR 1983; 141:781-788. Petersson CJ. Spontaneous medial dislo-
cation of the tendon
of the long
brachii.
1986;
Clin Orthop
D.
JJ,
4.
Neviaser RJ. Lesions of the biceps tendinitis of the shoulder. Orthop North Am 1980; 11:343-348. Slatis P, Aalto K. Medial dislocation
10.
Mag11.
of the head
of the biceps
and Clin of
bra-
chii. Acta Orthop Scand 1979; 50:73-77. Paavolainen P. Slatis P, Aalto K. Surgical pathology in chronic shoulder pain. In: Bateman JE, Welsh RP, eds. Surgery in the shoulder. Philadelphia: Decker, 1984; 313. Beltran J, Mosure JC. Magnetic resonance imaging of tendons. Crit Rev Diagn Imaging 1990; 30:111-182. Rowe CR. The shoulder. New York: Churchill Livingstone, 1988; 145.
biceps 211:224-227.
June 1991
Teresa
MD
#{149} Murray
MD
K. Dalinka,
J.
#{149} Bruce
Kneeland,
MD
#{149} Alain
MD
Chervrot,
Biceps Tendon Dislocation: Evaluation with MR Imaging’
D
The magnetic resonance (MR) images from six patients with biceps tendon dislocation two in whom
-
-
was surgically proved whom it was suspected spectively evaluated.
and
four
were
The
it
in
retro-
dislocated
tendon can be identified medial to the bicipital groove, best seen on the axial and oblique coronal and sagittal images. Associated abnormalities of the biceps tendon indude thickening (n 3), high signal intensity fluid (n contribute well seen
dude
=
abnormal (n
coracohumeral ruption
(n
=
shape
of the bicipi-
2), disruption ligament (n 4) and thinning =
of the subscapularis praspinatus tendon
tendon, tear (n
Since MR imaging modality of choice
tion
dislocation radiographic
(n 3), and surrounding 4). The factors thought to to dislocation can also be on MR images. These in-
tal groove
of the 6), dis(n 1)
and su4).
is becoming the for the evalua-
ages
derangements, faappearance of bitendon dislocation on MR imis important.
Index
terms:
miliarity
ceps
Tendons,
of shoulder with
the
Shoulder,
injuries,
41.42
MR studies, #{149} Tendons,
41.1214
#{149}
MR studies,
41.1214 Radiology
1991;
179:649-652
‘ From the Department of Radiology, Devon MRI Center, Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia, PA
19104.
Received
November
i2,
1990;
revision
requested December 18; revision received ary 23, 1991; accepted January 29. Address print requests to M.K.D. #{176}RSNA, 1991
of the biceps tendon is an uncommon, frequently unrecognized cause of shoulder pain (1). Although the clinical symptoms may be indicative of an isolated abnormality, they are more commonly associated with other shoulder abnormalities, particularly rotator cuff tears (2). Since the clinical presentation of rotator cuff tear and tendon ISLOCATION
Janure-
can be similar, accurate diagnosis is important difference in surgical man-
given the agement (2). The diagnosis of medial dislocation can be made by means of a demonstration of a medially dislocated biceps tendon sheath at arthrographic examination (3). The increasing use of MR imaging in the evaluation of the painful shoulder has made it easier to recognize this important abnormality. However, to our knowledge, only one case has been reported involving diagnosis of this entity with MR imaging (4). Our experience with six patients and the characteristic MR findings are the subject of this article.
MATERIALS
AND
METHODS
Among 420 shoulder MR examinations performed from January 1988 to September 1990 in our institution, a retrospective review of the MR images showed four patients to have presumed medial dislocation of the biceps tendon. Two additional cases were obtained from outside institutions that submitted studies to our department for consultation. Among these six patients, two had surgical confirmation of the MR imaging finding of biceps dislocation. The images from 10 control subjects with normal MR findings were used for comparison of the biceps tendon diameter, width and depth of the bicipital groove, and medial wall angle of the groove. All MR imaging was performed with a 1.5-T unit (GE Medical Systems, Milwaukee). The surface coils used were either a 5-inch Helmholtz pair or an anterior oval loop coil (Medrad, Pittsburgh). Axial images in four patients were obtained by us-
ing a multiplanar imaging sequence
fast time (TR) of 800 msec, of 15 msec (TR/TE 800/15), a flip angle of 70#{176}, a 14-cm field of view, 4-mm-thick contiguous sections, a 128 X 256 matrix, and two signals averaged. Two patients underwent axial Ti-weighted imaging (600/20). Coronal oblique Ti-weighted imaging (1,000/20) parallel to the supraspinatus muscle was performed with a 14cm field of view, a 3-mm interleaved gap, and two signals averaged. All subjects amderwent coronal oblique proton-densityweighted and T2-weighted imaging (2,500/20, 70) with a 14-16-cm field of view, a 5-mm section thickness with a 1mm gap, and two signals averaged. In some cases, additional sagittal oblique (perpendicular to the supraspinatus musdo) Ti-weighted or T2-weighted images were obtained by using similar parametens. The images were reviewed qualitatively by three
gradient-recalled with a repetition an echo time (TE)
radiologists
in concert
with
regard to the following: (a) location and signal intensity of the biceps tendon, (b) shape of the bicipital groove, (c) presonce of fluid in the joint and tendon sheath, and (d) integrity of the supraspinatus tendon, subscapularis tendon, and adjacent ligamentous structures. In addition, quantitative measurements in these six patients, as well as in the 10 control subjects, were obtained by one of the radiologists (T.W.C.) as follows. The biceps tendon diameter was measured at the widest point of its extracapsular portion. In cases in which the tendon had an ovoid or irregular shape, the length of the greatest transverse dimension and that perpendicular to it were obtained and averaged. The width of the bicipital groove was measured between the superior margin of the lesser and greater tuberosities. The depth of the groove was meastared at the same level. The medial wall angle was measured at the intersection between a line drawn tangential to the superior margins of the greater and lesser tuberosities and a second line tangential to the medial wall of the bicipital groove. These methods are similar to those used with plain radiographs in the study of Cone et a! (5). The normal anatomy of the biceps tendon on MR images is illustrated in Figure 1. 649
MR Findings
of Medial Biceps
Dislocation
of the Long Bicipital
Patient No/Age (y)
High Signal Intensity
Diameter (cm)
1/73 2/61
7 8 8 5 5 5
3/65
4/35’ 5/23 6/55
Shape
Yes Yes Yes No No No
Depth (mm)
8 8 10
5 5 6
8 8
3 5
tuberosity depth and
Table
summarizes
in the
images,
the
contains
six
the
MR
patients.
bicipital
the
On
groove
biceps
axial
normally
tendon
(Fig
ia).
The medially dislocated tendon can be well seen on coronal and axial images (Figs 2, 3). On axial views, the bicipital groove was empty (Fig 3). In one patient, a structure with low signal
intensity,
presumably
an
osteo-
the
the
tendon
region
brum,
was
of the
displaced
anterior
simulating
By following
nial
axial
this
sections,
tear
la-
(Fig
structure
one
can
on se-
differenti-
ate between and a torn the tendon
the displaced tendon labrum. More infeniorly, is located either just me-
dial
lesser
to the
tuberosity
(three
pa-
tients) or in a more medial position between the tuberosity and the glenoid (three patients). In the two patients
in whom
don was
the
4.9 mm difference
subscapulanis
biceps tendon group was of the control
of patients
High don (Fig
signal
was
groove
disposes
wall
55.0#{176}± 16.9#{176}for 64.5#{176}± 9.8#{176} for
For the 650
study
#{149} Radiology
not
the
have
dislocation
angle the the
group,
around
study
the
8.4
displaced
in
-
mm
±
the
supra-
The
coracohumeral
which
was
present
was
The pected tients.
a
ligament,
in all control
absent
in all
six
biceps dislocation clinically in any The patient with tear
sub-
patients.
was not susof the six pathe acute su-
(patient
5) under-
a primary repair of the rotator Persistent pain and limitation of necessitated a subsequent bitenodesis. Patient 4 also undera biceps tenodesis and subsca-
pulanis
tendon
patients
are
uals.
The subin one of in the
The
reattachment.
young,
other
Both
active
‘
b. ,,
.
four
rently undergoing tive therapy.
patients
a trial
and
of the
long
head
arises
The
from
the
of the
scapula.
of the
are
biceps
supraglenoid
The
Figure
1.
MR images
of normal
biceps
ten-
don. (a) Multiplanar gradient-recalled axial image (800/15; flip angle, 70#{176}) shows the biceps tendon as a round, low-signal-intensity structure within the bicipital groove. The tendon of the subscapularis muscle (arrow) is seen sweeping anterior to this as it inserts onto the lesser tuberosity. The transverse ligament is seen as a low-signal-intensity structure bridging the greater and lesser tuberosities (arrowhead). (b) Ti-weighted coronal oblique image (600/20) shows the biceps tendon (black arrow) passing under the fanlike subscapularis tendon (white arrow) as it enters the bicipital groove. The coracohumeral ligament is seen extending from the coracoid process to the lesser tuberosity (arrowhead). (c) Proton-density-weighted sagittal oblique image (2,500/20) shows the biceps (arrowhead) and the supraspinatus (open arrow) and subscapularis (solid arrow) tendons.
cur-
of conserva-
DISCUSSION
group.
c.
individ-
pre-
group
a.
biceps
patients,
other.
(7).
width
the
In two
measured
control
measured
MR
Associated abnormalities of the notator cuff were found in all six patients. Large tears of both the supraspinatus and subscapularis tendons were seen in three patients. These occurred in the absence of recent trauma and were associated with muscle atrophy. A moderate-sized tear of the supraspinatus tendon was present in one patient with a history of acute
went cuff. motion ceps went
ten-
implicated
that
groove
praspinatus
multi-
seen
as a factor
to tendon
medial
is
sequences.
subjects. studies
shallow The
study
within
fluid
jects,
of this the
in three patients with the axial
characteristic
control Previous
± was
biceps tenthickened Figs 2, 3).
gradient-recalled
This the
intensity
was present 3), best seen
planar
diameter 6.3 mm group
in this
small. Qualitatively, the don appeared abnormally in three patients (Table;
identifiable on the axial therefore, not measurable.
0.89 and the depth was 4.8 mm ± 1.1. In the control group, these measurements were 7.9 mm ± 0.74 and 5.9 mm ± 1.4, respectively. Qualitatively, two patients were thought to have an abnormal groove (Fig 5). A large amount of joint fluid was seen in two patients and a moderate amount in one. In all three patients,
trauma.
ten-
± .75. The significance is uncertain, since
number
but no greater tuberosity medial wall angle were,
‘
Tear Thin Tear Tear Normal Tear
spinatus tendon was intact. scapularis tendon was torn these patients and was thin
was intact, the biceps tendon located deep to it (Figs 3b, 4c).
The mean for the patient 1.5 and that
45#{176} Large tear 65#{176} Intact 70#{176} Largetear Intact 30#{176} Acute tear 65#{176} Large tear
joint. to
glenoid
a labral
3a).
Subscapularis Tendon
tendon was also seen. In another patient, fluid was seen around the displaced biceps tendon but not in the
phyte, was identified within the groove on a single section, mimicking the normal tendon. In two patients,
Tendon
Supraspinatus Tendon
Angle
bicipital
RESULTS The
of the Biceps
Groove
Width (mm)
Normal Normal Normal Shallow Shallow Normal
. This patient had a prominent lesser images. The bicipital groove width and
findings
Head
Tendon
intraarticular
tendon tubercie
por-
tion of the biceps tendon runs deep to the coracohumeral ligament, which bridges the interval between the supraspinatus and subscapularis tendons. As the tendon enters the bicipital groove, it lies beneath the thin intertubercular transverse ligament.
June
1991
-----
-
,i
.
....
‘
..
..
4l
c,
.
i#{149}*
#{248}4%
.t.,
#{188}
Figure 2. MR image of patient 1, who had a presumed dislocation of the biceps tendon and large tears of the supraspinatus and subscapularis tendons. Proton-densityweighted oblique coronal image (2,500/20) shows the biceps tendon medial to the groove
a.
b.
Figure 3. MR images from patient (a) Axial multiplanar gradient-recalled
biceps
tendon
(arrow)
ing an anterior
glenoid
cated biceps
(arrow)
2, who image
with a triangular labral
tear.
had
shape
(b) A more
a presumed (800/15;
dislocation
flip
angle,
of the biceps
tendon.
and high signal
70#{176}) shows the thickened intensity within it, mimick-
inferior
shows
section
is deep to the thin subscapularis
that
the medially
dislo-
tendon.
(arrow).
patients, a low-signal-intensity ture, presumably an osteophyte in the
b. Figure 4. Diagrammatic (.),subscapularis tendon
axial
representation
c. of the relationship
between
the biceps
tendon
and transverse ligament (arrowhead). (a) Normal anatomy. (b) With rupture of the transverse ligament and intact subscapularis, the biceps lies medial and anterior to the subscapularis. (c) With degeneration of the insertion of the subscapularis tendon to the lesser tuberosity, the biceps dislocates beneath the subscapularis, which remains attached to the greater tuberosity through the transverse ligament (adapted from reference 6). (*),
and the coracohumeral ligaments are the major restraints preventing dislocation of the biceps tendon (6,8,9). Disruption of these structures is believed to predispose to dislocation. The relationship between the appearance of these structures on axial images is illustrated in Figure 4. In the axial plane, the normal biceps tendon can be seen as a low-signal-intensity, usually ovoid structure in the
Figure 5. Ti-weighted axial image (600/20) of patient 4, who had a shallow bicipital groove and surgically proved dislocation of the biceps tendon. The lesser tuberosity is prominent, but the greater tuberosity was not identifiable on any of the axial images. The biceps tendon (arrow) is medial to the lesser tuberosity. The normal dark fibers of the subscapularis tendon are not seen.
More infeniorly, the tendinous toralis ligament.
Volume
major
it is held in place by expansion of the pec-
muscle, the The subscapularis
179
#{149} Number
3
falciform tendon
bicipital
groove
(Fig
ia).
On
anterior coronal oblique images, it is seen as a linear structure between the greater and lesser tuberosities (Fig ib). The relationship between the biceps tendon and the more superficial coracohumeral ligament and the subscapularis tendon is well demonstrated on anterior coronal oblique images (Fig ib). The medially displaced biceps tendon can be best seen in the axial plane, although coronal oblique and sagittal oblique images are helpful for confirmation. On axial images, one cannot identify the low-signalintensity tendon that is normally situated on the groove. In one of our
groove,
on one
image.
may
next
lie
mimicked
The
strucwith-
the
tendon
displaced
to the
anterior
tendon glenoid
labrum, simulating a labral abnormality. Careful tracing of the course of the tendon on serial axial images would avoid these potential pitfalls. Other abnormalities of the biceps tendon included increased signal intensity, which may be due to tendinitis (10), and thickening of the tendon, which is thought to represent a compensatory response to chronic rotator cuff tear (ii). Radiographic study of the anatomy of the bicipital groove has been performed by using special tangential views (5). The radiographic findings were in agreement with earlier anatomic
studies
strated poses though groove
that a shallow groove predisto tendon dislocation. Alour series is small, a shallow was present in two of our six
(7,8),
patients. Abnormalities
tendon however, our
which
of the
are relatively they were
patients.
Four
demon-
subscapulanis
uncommon; present in five patients
had
of
dis-
ruption of the subscapulanis tendon, three of whom also had large supraspinatus tendon tears. In one patient (patient
2), the
was
thin.
mal
subscapulanis
subscapularis
The tendon
one
tendon
a nor5) had an acute supraspinatus rupture. These findings are similar to those from a previous clinical study, which showed that degeneration of the subscapularis tendon insertion was a common predisposing factor to medial dislocation
The
of the
patient
with
tendon
(patient
biceps
clinical symptoms dislocation are
(6).
of biceps nonspecific Radiology
#{149} 651
and are often masked by those of a concomitant rotator cuff tear. In young, active patients, accurate diagnosis is particularly important, since repair of the rotator cuff tear without biceps tenodesis may not fully relieve the symptoms or restore the complete range of motion (8). The characteristic findings of biceps dislocation are easily seen on
MR images. Because MR imaging is becoming the modality of choice for the noninvasive diagnosis of soft-tissue abnormalities about the shoulder, familiarity this entity tant. U
652
with the appearance of on MR images is impor-
#{149} Radiology
7.
References 1.
2.
DePalma AF. Surgery of the shoulder. 2nd ed. Philadelphia: Lippincott, 1983; 270-272. Burkhead WZ Jr. The biceps tendon. In: Rockwood CA Jr, Matson FA III, eds. The
8.
shoulder.
9.
Philadelphia:
Saunders,
1990;
the tendon
791-832. 3.
Goldman AB. Double contrast shoulder arthrography. In: Freiberger RH, Kaye eds. Arthrography. New York: PrenticeHall, 1979; 165-188.
S, Resnick
Kursunoglu-Brahme
5.
netic resonance imaging of the shoulder. Radiol Clin North Am 1990; 28:941-954. Cone RO, Danzig L, Resnick D, Goldman
6.
AB. The bicipital groove: radiographic, anatomic, and pathologic study. AJR 1983; 141:781-788. Petersson CJ. Spontaneous medial dislo-
cation of the tendon
of the long
brachii.
1986;
Clin Orthop
D.
JJ,
4.
Neviaser RJ. Lesions of the biceps tendinitis of the shoulder. Orthop North Am 1980; 11:343-348. Slatis P, Aalto K. Medial dislocation
10.
Mag11.
of the head
of the biceps
and Clin of
bra-
chii. Acta Orthop Scand 1979; 50:73-77. Paavolainen P. Slatis P, Aalto K. Surgical pathology in chronic shoulder pain. In: Bateman JE, Welsh RP, eds. Surgery in the shoulder. Philadelphia: Decker, 1984; 313. Beltran J, Mosure JC. Magnetic resonance imaging of tendons. Crit Rev Diagn Imaging 1990; 30:111-182. Rowe CR. The shoulder. New York: Churchill Livingstone, 1988; 145.
biceps 211:224-227.
June 1991
