Keywords:
Musculoskeletal joint, Anatomy, MR, CT, Arthrography, Diagnostic procedure, Education and training
Authors:
I. Bougamra1, H. Riahi2, M. Chelli Bouaziz2, M. F. Ladeb2; 1Neuchâtel/CH, 2Tunis/TN
DOI:
10.26044/essr2019/P-0054
Imaging findings OR Procedure Details
Normal AMR imaging appearance of the intra-articular gleno-humeral structures is not different from the appearance of other tendons and ligaments.
On suppressed and non supressed T1,
T2 and intermediate weighted MR images,
ligaments,
labrum and biceps brachii tendon are typically hypointense.
On ACT those structures are hypodense within contrast media.
Biceps Brachii anatomy Originate from supraglenoid tuberosity,
labrum (anterosuperior and posterosuperior) or coracoid process.
It has an oblique intra-articular course,
traverses the rotator interval and exits the joint between the lesser and greater tuberosities into the bicipital groove.
Biceps Brachii variants Variations of the LHB tendon are common.
Complete absence of the intra-articular portion of the tendon.
One or more supernumerary heads.
Aponeurotic extension of the superficial supraspinatus tendon seen anteriorly and laterally to the biceps tendon Fig. 1 Fig. 2
Bicipital-labral complex anatomy Also called biceps anchor.
The region of attachment of the LHB tendon to the superior labrum.
Bicipital-labral complex variants Three different types of attachment of the biceps tendon on the supraglenoid tubercle:
- Type I: biceps firmly attached to the glenoid rim with no free edge Fig. 3 Fig. 4
- Type II: attachment of biceps to the glenoid is more medial with a small sulcus between the labral-free edge and cartilage with synovial lining.
Fig. 5 Fig. 6
- Type III: has a deep recess,
sublabral recess or sublabral sulcus,
located between the 11 and 1 o’clock position Fig. 7 Fig. 8
Rotator cuff interval anatomy
Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 18
Labrum anatomy
The glenoid labrum is a fibrous and fibrocartilaginous structure that rims the glenoid and circularly covers the glenoid cavity.
Fig. 22 Fig. 23 Fig. 24 Fig. 25
- Superior part of the labrum and capsule
-
- meniscal appearance
- loosely attached to the glenoid
- mobile
- Inferior part of the labrum:
-
- Round
- Elevated
- fibrous structure firmly attached to the glenoid
Labrum variants
- Rounded (more frequent)
- Flat
- Cleaved
- Notched
- Absent
- The sublabral foramen: Fig. 26 Fig. 27 Fig. 28 Fig. 29
-
- labrum completely separated from the glenoid in this superior part
- 12–18.5 %
- between the 1- o’clock to 3-o’clock position
- smooth margins of the foramen
- no significant displacement (1-2mm)
- no associated traumatic injuries
- possible association with labral recess Fig. 34 Fig. 35
Superior gleno-humeral ligament anatomy
- Consists of direct and oblique fibres Fig. 36 Fig. 37
- Direct fibres
-
- originate from the glenoid labrum
- run parallel with the tendon of the long head of the biceps muscle
- insert partly onto the lesser tuberosity,
into the bottom of the intertubercular groove and partly bridge over the groove,
forming the upper part of the transverse humeral ligament.
- Oblique fibres
-
- originate from the supraglenoid tubercle
- run over the intra-articular part of the tendon
- insert under the coracohumeral ligament into the semicircular humeral ligament
Superior gleno-humeral ligament variants
- Absent: 3%
- Direct origin from the biceps tendon
- Common origin with the MGHL Fig. 38
- Thickened with underdeveloped or absent MGHL
Middle gleno-humeral ligament anatomy
- Originates from the labrum either separately or at the origin of the SGHL Fig. 39 Fig. 40
- blends with portions of the subscapularis tendon approximately 2 cm medial to its insertion on the lesser tuberosity
Middle gleno-humeral ligament variants
- The MGHL is the most variable ligaments among the glenohumeral ligaments
- Absent: 30%
- Conjoined origin with either the SGHL or IGHL
- Conjoined origin with the biceps tendon alone and absent SGHL may also be observed
- Duplicated Fig. 41
Inferior gleno-humeral ligament anatomy
- A hammock structure of the capsule Fig. 42
- Extend from the antero inferior to the postero inferior portions of the glenoid
- Antero inferior attachments: located from 2 o’clock to 5 o’clock of the glenoid
- Humeral attachment: along the inferior margin of the articular surface and around the anatomical neck,
below the lesser tuberosity
Inferior gleno-humeral ligament variants
- Glenoid attachments:
-
- Type 1: major attachment to the labrum with some fibres extending onto the glenoid neck,
80%
- Type 2: attaches solely to the glenoid neck,
20% Fig. 43 Fig. 44 Fig. 45 Fig. 46
- Prominent synovial folds at the axillary recess
- Relationship between the long head of the biceps origin and the level of the anterior band of the IGHL origin from the anterior labrum
- Origin of the anterior band of the IGHL from the MGHL.