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Colin L. Eakin, MD et al ABSTRACT Athletes, especially those who
participate in overhead activities, suffer significant stresses to the
shoulder joint. Biceps
injuries and lesions appear to occur commonly with other shoulder
conditions, and should be thoroughly evaluated when other lesions are
present. Recent studies have found high interest in this tendon as it
relates to SLAP lesions, and there are now associations with subscapularis
lesions, and “hidden” lesions of the rotator interval. Anatomy review tells us that the
short head originates from the coracoid process with the coracobrachialis,
and combine to form the conjoined tendon.
The long head appears to have variable originations.
One study found that 48% originated from the posterior labrum,
while 20% originated from the supraglenoid tubericle.
Another found that 28% originated from both sides, while another
found that 50% of the tendon originated from the superior labrum and the
other from the supraglenoid tubericle. Cooper et al even suggested that the looseness at the
superior labral attachment site may actually be normal and should not be
treated as a presumed SLAP lesion. Within the GH joint, the tendon is
intra-articular but extrasynovial, and is covered by a synovial lining
from the articular capsule. The
tendon exists the GH joint and passes deep to the coracohumeral ligament
and through the rotator interval, and then travels through the bicipital
groove and under the transverse ligament.
It is also covered at this area by an aponeurosis of the pectoralis
major. Studies have indicated that the
biceps acts as a humeral head depressor and stabilizer of the GH joint,
with transection in cadaver models causing significant superior migration
of the humerus. Its
contribution to anterior stabilization appears to increase in cases of
greater instability, especially with the arm in abduction and external
rotation. Here it appears to
produce an increase in torsional rigidity of the anterior capsule and
promote stability. Athletes
with GH instability reveal greater biceps EMG activity, and superior
labral biceps detachment causes greater strains on the inferior
glenohumeral ligament. During throwing in normal
shoulders, the biceps acts as a strong elbow flexor, with moderate
activity in the cocking phase, reduced activity during the acceleration
phase, and high activity at follow-through, where it tries to avoid
hyperextension of the elbow. This
is the period of the throw where many SLAP lesions occur.
During throwing, the brachialis muscle assists it, and athletes
with greater skill and control may be able to control these deceleration
muscles better and reduce their strain. The term biceps tendonitis is often
used, and should actually be called tendinosis or tendon degeneration.
The process does not have a true inflammatory component, and
findings include atrophy of collagen fibers, irregular collagen fiber
patterns, fissuring of the tendon, fibrinoid necrosis, and fibrocyte
proliferation. Type III
acromions and tight posterior capsules both contribute to a greater
likelihood of impingement, which Neer notes are the greatest cause of
biceps degeneration. Weakness
to the serratus anterior, or fatigue of this muscle, increases the
likelihood of impingement, as the acromion is unable to rotate out of the
path of the forward elevating humeral head. Osteophyte formation and narrowing
of the bicipital groove can facilitate tendinosis, and some authors
indicate that most of the process occurs at the level of the groove, as
the upper tendon remains pristine in many cases.
Rupture can occur, resulting in 21% loss of supination strength,
and 8% loss of elbow flexion strength.
These authors have found that in athletes having tendinosis yet
high demands for overhead activity, performance improves and pain reduces
after removal of the diseased tendon (either via surgery or rupture). Lesions at the origin can occur
during throwing when there is sudden deceleration of elbow extension
during follow through. Type I
SLAP lesions involve tissue degenerative fraying but still intact biceps
attachment. Type II has the
biceps anchor pulling away from the glenoid attachment.
Type III has a bucket handle tear of the labrum with an intact
biceps anchor, and Type IV adds the Type III tear into the tendon.
These authors believe that direct compression shear of the anterior
shoulder, from either excessive overhead activity or a fall on an
outstretched flexed arm, are the major causes.
The destabilization seen with the SLAP lesion leads to increased AP
and superior-inferior migration, and increased torsion on the inferior GH
ligament. Gerber et al have suggested that in
those with subluxation or dislocation of the tendon, an associated tear of
either the subscapularis or rotator interval is likely.
Patients will usually complain of anterior pain, but the pain may
also be vague. There may be
complaints of snapping, grinding, and popping.
SLAP lesions will usually present as a popping sensation deep in
the shoulder. Special testing
can include the Yergason test, Speed’s test, apprehension test,
relocation test, sulcus test, and load-shift test.
Placing the arm in 90 degrees abduction and then full IR, and
assessing for either a click or pain can test the SLAP lesion.
Another new test takes the arm into 90 degrees flexion and 20
degrees adduction, and resistance is applied while the thumb points down.
Pain at this time, but not when the thumb is up, presumably
stresses the superior labrum. Conservative care includes resting,
ice and NSAID therapy. A
light injection of steroid and anesthetic can be beneficial for those who
have to continue with activity despite severe pain, and can actually be
diagnostic. Rehab should
include strengthening of the internal rotators, which act eccentrically
during late cocking to avoid excessive anterior strain.
The serratus and trapezius should be addressed, and also training
of the biceps itself. Surgery includes simple
decompression if the tendon appears to be stable and intact, or tenodesis
of the tendon appears damaged. The
procedure usually takes the tendon and creates a new origin in the region
of the bicipital groove, with a few different anchoring methods used by
different physicians. In
cases where the tendon is severely frayed, the patient is older, or an
athlete really wants to return to sport, a tenotomy is performed. COMMENTS I have always considered and called
the biceps tendon the “fifth rotator cuff”, and this article supports
this idea. After all, how
many patients have we seen with rotator cuff problems, and they also have
co-existing biceps tendon problems? The
same mechanical dysfunctions that lead to rotator cuff injuries also
aggravate the biceps tendon. The
fact that inflammation in these cases is not as prominent as actual tissue
degeneration may explain why anti-inflammatory treatments do not always
work. The patient should understand the risks of corticosteroid
injection, and those who are injected should be treated carefully to avoid
rupture of the tendon. As the authors suggest, those with
subluxation of the tendon appear to have, almost always, injury to the
rotator interval and the subscapularis tendon.
Consider this when treating and evaluating. Also, consider when treating the
fact that the biceps itself needs to be strengthened. As the coracobrachialis has co-attachment, perform your
shoulder theraband flexion with the palm supinated.
I have always done this to address both the long biceps and the
coracobrachialis, and reduce the rotator cuff supraspinatus strain that
occurs with the pronated arm. When
strengthening the elbow flexors, remember to perform your curls in all 3
hand positions: fully
supinated for the biceps, neutral for the brachioradialis, and pronated
for the brachialis. The authors give many special tests
to use for SLAP lesions, but none have any high specificity or
sensitivity. I have asked
many surgeons if they have found any test that always works for them, but
none have. You can use the
tests to help you steer down a certain path, but don’t rely on their
results too much. Remember to work on the lower
trapezius, the serratus and even the triceps muscles. Also, remember to work on the eccentric control of the
shoulder to control the follow-through of a throw.
Taping the shoulder, via pulling the humeral head back, really
works well for patients, and I find myself doing this quite often now.
It may not actually be reducing the humeral head and taking the
strain off the anterior tissues, but rather be reminding the patient via
sensory feedback to protect the shoulder.
Either way, it works. If the subject with the biceps
tendinopathy is a weight lifter, you will find that they usually have pain
and incurred their injury when bench pressing (usually wide gripped), or
military press or incline bench. If
the subject is over the age of 35, tell them to discontinue lifting with a
flat bar or risk continued injury and possible loss of lifting capability
for life. Use of hand
dumbbells works the same groups, is actually a little harder due to the
balance component, and is a safer alternative.
The flat bar forces the shoulder through the motions dictated by
the way the bar moves. The
dumbbells permit rotation of the forearm and shoulder to reduce
impingement and strain.
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