In the preoperative area, an interscalene regional block is placed by the
anesthesiologist. In our experience, this is safe and provides excellent
postoperative analgesia. The patient is then brought to the operating room
where general anesthesia is induced. Intravenous antibiotics are given one
hour prior to incision and are continued for twenty-four hours
postoperatively.
The patient is placed in a semireclining beach-chair position with the head
of the bed elevated to 45°. A standard deltopectoral incision is made from
just inferior to the clavicle, extending over the coracoid process for
approximately 12 to 15 cm distally. The fat stripe indicating the interval
between the pectoralis major and the deltoid is identified. The cephalic vein
is typically preserved and retracted laterally with the deltoid muscle, which
it drains. Next, the superior 1 cm of pectoralis major tendon is tagged and
incised to improve exposure. The coracoacromial ligament is preserved to
prevent anterosuperior migration of the humerus. The clavipectoral fascia is
incised just lateral to the conjoint tendon, and a Richardson retractor is
placed between the humerus and the deltoid to help to free up adhesions. The
subscapularis tendon and capsule are incised laterally, tagged with sutures,
and mobilized from the anterior glenoid rim to increase excursion for superior
translation at the end of the procedure
(Fig. 1). The humeral head is
dislocated by a combination of gentle external rotation, adduction, and
extension of the arm, as the inferior capsule is released from the medial
aspect of the humeral neck. In most cases, because of the massive rotator cuff
tear and loss of superior rotator cuff tissue, the head is readily presented
(Fig. 2). Osteophytes are
removed from the medial aspect of the humeral neck. The starting point for
canal reaming is just posterior and medial to the bicipital groove, and
reaming is performed by hand in 1-mm increments until a snug cortical fit is
obtained. An oscillating saw and cutting guide are used to resect the humeral
head in approximately 30° of retroversion, and a trial stem is
inserted.
An attempt is made in all patients to mobilize the residual rotator cuff
and at least partially repair the posterior part with heavy nonabsorbable
sutures. The undersurface of the acromion is inspected because the leading
edge of the posterior aspect of the rotator cuff is often adherent in this
area. Mobilization of the tagged rotator cuff can be facilitated by releasing
the capsule and the cuff as a single structure at the glenoid rim
(Fig. 3). Once the leading edge
of the posterior aspect of the rotator cuff is found, it is tagged with
nonabsorbable sutures and freed superomedially and posteroinferiorly (Figs.
4 and
5). It is important to note
that the residual rotator cuff insertion onto the humerus is never detached.
It is important not to overstuff the joint with a larger head, as this will
place greater tension on the rotator cuff repair by increasing the distance
from the scapula to the humerus. Matching the head size also facilitates
closure and superior shift of the subscapularis. A humeral head trial, sized
to the resected humeral head (Fig.
6), is placed onto the humeral stem, and a trial reduction and a
reapproximation of the rotator cuff is performed
(Fig. 7). Prior to implantation
of the final component, multiple sutures are placed through osseous tunnels in
the greater and lesser tuberosities for cuff reattachment. The final modular
stem is cemented in 30° of retroversion, and the final head component is
impacted onto the Morse taper of the stem
(Fig. 8). The rotator cuff is
then reattached with use of the sutures previously placed in the humeral bone
tunnels (Fig. 9). If enough
tissue is available, the subscapularis tendon is transposed to the superior
aspect of the greater tuberosity to improve superior head coverage, as
described by
Cofield5
(Fig. 10). If superior
coverage is not obtainable, emphasis is placed on achieving stable anterior
and posterior buttresses. Complete superior coverage was obtained in twelve of
the thirty-four patients in our series
(Fig. 11).
A suction drain is placed, and the deltopectoral interval is closed. The
skin is reapproximated with a subcuticular suture.
The drain is removed twenty-four hours after the procedure.
Postoperatively, the patient wears a sling for three weeks; it is taken off
only for bathing and exercise. On the first postoperative day, passive motion
exercises, consisting of pendulum exercises and external rotation exercises
with a stick, are started. Outpatient rehabilitation consists of passive
motion to 30° of external rotation and supine forward elevation to
130° for eight to twelve weeks. Active-assisted exercise and isometrics
are started at eight to twelve weeks with the patient in a seated position and
movement performed below the horizontal. At twelve weeks or when the patient
demonstrates good arm control, active exercise to tolerance and gentle
resistance exercises are begun. We recommend that patients participate in the
supervised postoperative physical therapy program for at least three months
after surgery.
CRITICAL CONCEPTSINDICATIONS:Osteoarthritis of the shoulder with a large or massive tear of the rotator
cuffRotator cuff tear arthropathyForward elevation of >90°CONTRAINDICATIONS:Anterosuperior escape, a condition in which the humeral head slides
anterior to the acromion and then superior during attempted elevation of the
arm, as a result of an incompetent or missing coracoacromial ligamentEvidence of coracoacromial arch insufficiencyPreoperative active forward elevation of <90°PITFALLS:Placement of a humeral head component that is either too large or too
small. A large humeral head can overstuff the joint, placing excess tension on
the rotator cuff and leading to failure of the repair. A humeral head that is
too small may allow excessive motion, predisposing to instability, and also
may alter the normal resting length of the rotator cuff muscles, reducing
their strength.Failure to mobilize and at least partially repair the remaining rotator
cuff tissue. We believe that any amount of rotator cuff tissue that is freed
and can be repaired will only help to increase the functional ability of the
patient.Removal of any of the coracoacromial arch, which can lead to anterosuperior
escape.AUTHOR UPDATE:The patients in the study had the operation between 1985 and 2000, and
substantial improvements have been made in the design of the original
monoblock humeral prosthesis since then. We currently use a modular humeral
stem that offers multiple choices of head heights and diameters. In addition,
the head can be centered on the Morse taper or placed in an offset position to
maximize bone coverage. Surface replacement of the humeral head has also
become an option. There have not been any major changes to the method of
repairing the rotator cuff.
CRITICAL CONCEPTS
INDICATIONS:
Osteoarthritis of the shoulder with a large or massive tear of the rotator
cuffRotator cuff tear arthropathyForward elevation of >90°
Osteoarthritis of the shoulder with a large or massive tear of the rotator
cuff
Rotator cuff tear arthropathy
Forward elevation of >90°
CONTRAINDICATIONS:
Anterosuperior escape, a condition in which the humeral head slides
anterior to the acromion and then superior during attempted elevation of the
arm, as a result of an incompetent or missing coracoacromial ligamentEvidence of coracoacromial arch insufficiencyPreoperative active forward elevation of <90°
Anterosuperior escape, a condition in which the humeral head slides
anterior to the acromion and then superior during attempted elevation of the
arm, as a result of an incompetent or missing coracoacromial ligament
Evidence of coracoacromial arch insufficiency
Preoperative active forward elevation of <90°
PITFALLS:
Placement of a humeral head component that is either too large or too
small. A large humeral head can overstuff the joint, placing excess tension on
the rotator cuff and leading to failure of the repair. A humeral head that is
too small may allow excessive motion, predisposing to instability, and also
may alter the normal resting length of the rotator cuff muscles, reducing
their strength.Failure to mobilize and at least partially repair the remaining rotator
cuff tissue. We believe that any amount of rotator cuff tissue that is freed
and can be repaired will only help to increase the functional ability of the
patient.Removal of any of the coracoacromial arch, which can lead to anterosuperior
escape.
Placement of a humeral head component that is either too large or too
small. A large humeral head can overstuff the joint, placing excess tension on
the rotator cuff and leading to failure of the repair. A humeral head that is
too small may allow excessive motion, predisposing to instability, and also
may alter the normal resting length of the rotator cuff muscles, reducing
their strength.
Failure to mobilize and at least partially repair the remaining rotator
cuff tissue. We believe that any amount of rotator cuff tissue that is freed
and can be repaired will only help to increase the functional ability of the
patient.
Removal of any of the coracoacromial arch, which can lead to anterosuperior
escape.
AUTHOR UPDATE:
The patients in the study had the operation between 1985 and 2000, and
substantial improvements have been made in the design of the original
monoblock humeral prosthesis since then. We currently use a modular humeral
stem that offers multiple choices of head heights and diameters. In addition,
the head can be centered on the Morse taper or placed in an offset position to
maximize bone coverage. Surface replacement of the humeral head has also
become an option. There have not been any major changes to the method of
repairing the rotator cuff.