Surgical release for stiff frozen shoulders: Surgery to remove scar tissue and release contractures can lessen pain and improve function for stiff shoulders that have not responded to rehabilitation or physical therapy.
Last updated Wednesday, January 26, 2005
Figure 1 - Axillary nerve Figure 2 - Subscapularis lengthening Figure 3 - "360 degree" release Figure 4 - Releasing the inferior capsule sharply while a finger protects the axillary nerve Figure 5 - Releasing the posterior capsule up to the origin of biceps tendon at the supraglenoid tubercle Surgical approaches
The type of stiffness dictates the surgical approach to the refractory stiff shoulder.Usual approach We usually approach a post-surgical stiff shoulder through an
incision that provides access to the previous surgical site. This is
because the densest adhesions and scar are usually located beneath the
surgical incision. The idiopathic frozen shoulder is reached through a
deltopectoral approach, which allows access to the rotator interval,
the motion interface, the subscapularis, and the glenohumeral joint
capsule. The surgical release is analogous in many ways to the
subscapularis and capsule release performed during a glenohumeral
arthroplasty.
We proceed sequentially through a series of distinct stages of
shoulder release, reassessing the range of motion after each stage. We
continue through these stages until the desired motion is obtained. Stage one Re-establishment of the humeroscapular motion interface: Our in vivo
MRI studies demonstrated that there is normally a substantial excursion
at the humeroscapular motion interface. In post-surgical and
post-traumatic stiff shoulders, adhesions or "spot welds" are common
between the deltoid, acromion, coracoacromial ligament, coracoid, and
coracoid muscles on one hand and the rotator cuff and humerus on the
other. These spot welds can virtually eliminate motion at the
interface. Thus, each area of the interface needs to be smooth and free
of adhesions for the shoulder to achieve its normal range. At times the
motion interface can be obscured and difficult to identify.
In the "totally stuck shoulder" we start under the acromion, knowing
that it is part of the outer aspect of the motion interface. Dissecting
beneath the acromion and coracoacromial ligament with a knife, we can
free the subjacent cuff tissue. By rotating the humerus internally and
externally during this step of the dissection we continue the
dissection under the coracoacromial arch to the coracoid. Then the
sharp dissection proceeds beneath the coracoid and coracoid muscles,
freeing the subjacent subscapularis muscle.
Adhesions between the coracoid muscles and the subscapularis cause a
major limitation of external rotation owing to the magnitude of
interfacial motion here. It must be remembered that the brachial
plexus, especially the musculocutaneous and axillary nerves, are close
by and vulnerable. Thus we stay lateral to the coracoid muscles (the
"safe side") dissecting on the surface of the subscapularis as it is
externally rotated, rather than diving medial to the coracoid muscles
(the "suicide").
In a similar manner, sharp dissection continues laterally from the
acromion to reestablish the motion interface between the deltoid and
the rotator cuff. Again, the nerve supply, in this case the branches of
the axillary nerve, lie in the motion interface. We avoid them by
keeping our sharp dissection on the superficial aspect of the rotator
cuff and proximal humerus. If the dissection enters the deltoid muscle,
its nerve supply, the axillary nerve, is at risk. Stage two Opening the rotator interval: As our cadaver research has demonstrated,
tightness at the rotator interval can substantially restrict the range
of glenohumeral motion. We release the rotator interval by sharply
dissecting the subscapularis and supraspinatus tendons free from their
moorings to the base of the coracoid. We verify the completeness of
this release by passing a blunt elevator between the tendons on both
sides of the coracoid process.Stage three Reestablishment of subscapularis length and excursion: The
subscapularis and anterior capsule may be contracted and scarred,
particularly after previous anterior shoulder injury or surgery. We
perform a coronal plane "Z" lengthening of the subscapularis tendon and
capsule using a step cut. We cut the superficial lateral aspect of the
tendon at the lesser tuberosity near the long head of the biceps. We
then split the tendon medially in the coronal plane. Finally, we
complete the medial aspect of the cut by transecting the remaining
tendon and capsule adjacent to the glenoid labrum. At the conclusion of
the procedure we will suture the lateral end of the superficial flap to
the medial end of the deep flap.
Each centimeter of subscapularis lengthening gained by the step cut
increases external rotation by approximately 20 degrees. Prior to the
closure, we perform a "360 degree" release of the subscapularis tendon
from the coracoid muscles anteriorly, the axillary nerve below, the
capsule and scapular neck posteriorly and the coracoid above. This
release should reestablish the normal "bounce" and excursion of the
subscapularis. Stage Four Release of the capsule: Capsular tightness is the major component of an
idiopathic frozen shoulder, but it may also be a major component of
post-traumatic and post-surgical stiff shoulders. In the surgical
release, we section the tight capsular tissue just lateral to the
glenoid labrum. The capsule can be released selectively or
circumferentially according to the pattern of stiffness. A
circumferential capsular release can be started anterosuperiorly, then
carried down the anterior glenoid. We release the inferior capsule
sharply while a finger protects the axillary nerve. We expose the
origin of the triceps from the infraglenoid tubercle with this release.
We insert a humeral head retractor into the joint and twist it slightly
to tension the posterior inferior capsule so that it can be safely
sectioned. By twisting the retractor a little more with each bit of
posterior capsular release, we can safely release the posterior capsule
up to the origin of biceps tendon at the supraglenoid tubercle. The
lengthened subscapularis tendon is then sutured to the capsule attached
to the lesser tuberosity.Adequate release The hallmarks of an adequate release are:
- translation of the humeral head on the posterior drawer test of at least 1.5 centimeters,
- a "scarecrow" test demonstrating almost 90 degrees of internal
rotation of the arm elevated 90 degrees in the zero degree thoracic
plane,
- at least 45 degrees external rotation with the arm at the side, and
- total elevation of the arm to at least 140 degrees.
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