- Superior labral tears have been described, as shoulder
arthroscopy experience has increased. Open surgery
with the arthrotomy placed deep to the subscapularis
does not demonstrate this anatomy, and therefore little
has been mentioned in the literature (Snyder et al,
1990). - There can be anatomic variants and gradual develop-
mental changes with age and use, overuse leading to
tissue failure, and traumatic instability events.
Superior labrum anterior to posterior(SLAP) tears
may be an isolated etiology for shoulder pain or com-
bined with rotator cuff pathology.
•Overhead sports as in baseball pitching may place
additional stresses on the superior labrum. As sports
participation and injury recognition increases, so does
the experience in treatment of injuries to the superior
labrum (Andrews, Carson, Jr, and McLeod, 1985;
Abrams, 1991).
SUPERIOR LABRUM ANATOMY
- The labrum is a cartilaginous ring around the shallow
glenoid, contributing to depth and humeral head con-
tact (Howell and Galinat, 1989). Superior labrum
lesions can occur alone or combined with anterior or
posterior labral avulsions. - The superior labrum consists of dense fibrocartilage
and elastin that connects the superior and middle cap-
sular ligaments and long head of the biceps to the gle-
noid. - Common normal variants include a fovea, a Buford
complex, and a peel-back labrum. The fovea is an
incomplete anterior superior labral attachment to the
glenoid with a hole or thin fibrous tissue between the
labrum and the glenoid (Cooper et al, 1992). A Buford
complex is a thickened middle glenohumeral ligament
band that inserts at the biceps labral junction with an
absent anterior superior labrum (William, Snyder, and
Buford, 1994). A large fovea or superior labral
absence may mistakenly resemble an avulsion injury.
The posterior superior labrum may be attached to the
glenoid neck rather than to the articular surface.
Variations of labral attachment can be normal embry-
onic variants or repetitive activity adaptations. - Normal variants may predispose shoulders to addi-
tional injuries. Buford complexes do not have antero-
superior labrum. Visualizing below the biceps and
labrum often demonstrates abnormal wear suggesting
instability of the biceps anchor. - Superior labral tears (SLAP tears) have been classi-
fied by Snyder as type I degenerative, type II avulsion,
type III bucket-handle tears, and type IV combined
labral tear and biceps insertion split (Snyder, Banas,
and Karzel, 1995). Expanded classification includes
extension of Bankart lesions (Maffet, Gartsman, and
Moseby, 1995), associated rotator cuff articular-side
pathology, continuations of ganglion cysts.- The anatomy can be arthroscopically visualized in a
static and dynamic exam. The peel-back labrum can
be seen arthroscopically as loss of posterior superior,
glenoid contact when the shoulder is placed in abduc-
tion and external rotation (Burkhart and Morgan,
1998). An otherwise normal finding may increase
with repetitive stresses leading to a painful condition.
SUPERIOR LABRUM FUNCTION- Superior labrum contributes to superior, anteroinfe-
rior, and posterior glenohumeral stability. Superior
humeral head translation can be reduced with secure
attachment of the superior labrum and its biceps and
capsular attachments. Investigators have increased
anteroinferior translation after creating superior labral
tears (Rodosky, Harner, and Fu, 1994; Pagnani et al,
1995). In addition, arthroscopists have noted SLAP
tears associated with some cases of posterior instabil-
ity, multidirectional shoulder instability (Abrams,
2003). - The rotator cuff interval plays a role in stabilizing the
adducted shoulder (Harryman et al, 1992). This inter-
val consists of the superior labrum, superior gleno-
humeral ligament, middle glenohumeral ligament, and
coracohumeral ligament. Reduction of an enlarged
interval has decreased inferior translation or sulcus,
reduced anterior translation, and external rotation aug-
menting anterior repairs, and reduced posterior trans-
lation augmenting posterior repairs. - Superior translation of the humeral head can be lim-
ited with an intact superior labrum and biceps anchor
with the humerus in external rotation (Abrams, 1991).
The long head of the biceps attaches to the superior
labrum and glenoid tubercle. When the shoulder is in
the cocked throwing position (abduction, external
rotation, and extension), the head is translated poste-
riorly (Howell et al, 1988). Capsular changes and
tears in the superior labrum may alter these relation-
ships. - The superior labrum may contribute to articular
lesions on the undersurface of the rotator cuff. Internal
impingement is a common pathologic finding in over-
head throwers with shoulder pain. Excessive contact
of the posterosuperior labrum with the supraspinatus
during early acceleration can create partial-thickness
rotator cuff tears. Subscapularis tears can abrade on
the anterosuperior labrum with flexion and interval
rotation.
282 SECTION 4 • MUSCULOSKELETAL PROBLEMS IN THE ATHLETE