A SLAP tear or SLAP lesion is an injury to the Glenoid labrum.
SLAP is an acronym for "superior labral tear from anterior to posterior".
Overview The shoulder joint is a 'ball and socket'
joint.
However, the 'socket' is small, covering at most only a third of the 'ball'.
It is deepened by a circumferential rim of fibrocartilage, the glenoidal labrum.
Previously there was debate as to whether the labrum was fibrocartilaginous as opposed
to hyaline cartilage found in the remainder of the glenoid fossa.
Previously, it was considered a redundant, evolutionary remnant, but is now considered
integral to shoulder stability.
Most agree that the proximal tendon of the long head of the biceps brachii muscle becomes
fibrocartilaginous prior to attaching to the superior aspect of the glenoid.
The long head of the triceps brachii inserts inferiorly, similarly.
Together, all of those cartilaginous extensions are termed the 'glenoid labrum'.
A SLAP tear or lesion occurs when there is damage to the superior area of the labrum.
These lesions have come into public awareness because of their frequency in athletes involved
in overhead and throwing activities in turn relating to relatively recent description
of labral injuries in throwing athletes, and initial definitions of the 4 SLAP sub-types,
all happening since the 1990s.
The identification and treatment of these injuries continues to evolve.
Sub-types Although ten varieties of SLAP lesion have
been described on MRI or MR arthrography seven clinical types are generally described.
Type I. Degenerative fraying of the superior portion of the labrum, with the labrum remaining
firmly attached to the glenoid rim Type II.
Separation of the superior portion of the glenoid labrum and tendon of the biceps brachii
muscle from the glenoid rim Type III.
Bucket-handle tears of the superior portion of the labrum without involvement of the biceps
brachii attachment Type IV.
Bucket-handle tears of the superior portion of the labrum extending into the biceps tendon
Type V. Anteroinferior Bankart lesion that extends upward to include a separation of
the biceps tendon Type VI.
Unstable radial flap tears associated with separation of the biceps anchor
Type VII.
Anterior extension of the SLAP lesion beneath the middle glenohumeral ligament
Symptoms Several symptoms are common but not specific:
Dull, throbbing, ache in the joint which can be brought on by very strenuous exertion or
simple household chores.
Difficulty sleeping due to shoulder discomfort.
The SLAP lesion decreases the stability of the joint which, when combined with lying
in bed, causes the shoulder to drop.
For an athlete involved in a throwing sport such as baseball, pain and a catching feeling
are prevalent.
Throwing athletes may also complain of a loss of strength or significant decreased velocity
in throwing.
Any applied force overhead or pushing directly into the shoulder can result in impingement
and catching sensations.
Treatment Few with SLAP lesion injuries return to full
capability without surgical intervention.
In some, physical therapy can strengthen the supporting muscles in the shoulder joint to
the point of reestablishing stability.
For most others, the choice is to do nothing or some form of surgical repair.
While surgery can be performed as a traditional open procedure, an arthroscopic technique
Is currently favored being less intrusive with low chance of iatrogenic infection.
Associated findings within the shoulder joint are varied, may not be predictable and include:
SLAP lesion – labrum/glenoid separation at the tendon of the biceps muscle
Bankart lesion – labrum/glenoid separation at the inferior glenohumeral ligament
Biceps Tendon - exclusion of pulley injury Bone – glenoid, humerus — injury or degenerative
change involving joint surface Anatomical variants — sublabral foramen,
Buford Complex It should be noted that while good outcomes
with SLAP repair over the age of 40 are reported, both age greater than 40 and Workmen's Compensation
status have been noted as independent predictors of surgical complications.
This is particularly so if there is an associated rotator cuff injury.
In such circumstances, it is suggested that labral debridement and biceps tenotomy is
preferred.
Procedure
Following inspection and determination of the extent of injury, the basic labrum repair
is as follows.
The glenoid and labrum are roughened to increase contact surface area and promote re-growth.
Locations for the bone anchors are selected based on number and severity of tear.
A severe tear involving both SLAP and Bankart lesions may require seven anchors.
Simple tears may only require one.
The glenoid is drilled for the anchor implantation.
Anchors are inserted in the glenoid.
The suture component of the implant is tied through the labrum and knotted such that the
labrum is in tight contact with the glenoid surface.
Surgical rehabilitation Surgical rehabilitation is vital, progressive
and supervised.
The first phase focusses on early motion and usually occupies post-surgical weeks one through
three.
Passive range of motion is restored in the shoulder, elbow, forearm, and wrist joints.
However, while manual resistance exercises for scapular protraction, elbow extension,
and pronation and supination are encouraged, elbow flexion resistance is avoided because
of the biceps contraction that it generates and the need to protect the labral repair
for at least six weeks.
A sling may be worn, as needed, for comfort.
Phase 2, occupying weeks 4 through 6, involves progression of strength and range of motion,
attempting to achieve progressive abduction and external rotation in the shoulder joint.
Phase 3, usually weeks six through 10, permits elbow flexion resistive exercises, now allowing
the biceps to come into play on the assumption that the labrum will have healed sufficiently
to avoid injury.
Thereafter, isokinetic exercises may be commenced from weeks 10 through 12 to 16, for advanced
strengthening leading to return to full activity based on post surgical evaluation, strength,
and functional range of motion.
The periods of isokinetics through final clearance are sometimes referred to as phases four and
five.
References
External links slaptear.com FAQs, Blogs, and discussion about
slap tear injuries Radiographics search on Superior Labrum