Deep Dissection

Identify the subscapularis muscle and conjoint tendon (Fig. 2-20)

Expose the glenohumeral joint

• Exposure of the glenohumeral joint is dependent on the procedure and the surgeon’s preference

• For most procedures, release of the subscapularis tendon is necessary and may be performed via two different techniques

• Soft tissue subscapularis release either directly from bone or through the tendon substance

• Superficial osteotomy of the lesser tuberosity

Soft tissue exposure

• The subscapularis and capsule can be taken down together by making a vertical incision approximately 1 cm medial to the bicipital groove, placing traction sutures in the capsule and tendon, and dissecting along the neck of the humerus (Fig. 2-21)

• Most often used for arthroplasty

• The capsule can be dissected further inferiorly, directly off the neck of the humerus

• The axillary nerve should be identified and protected with inferior dissection

• The subscapularis and capsule can be taken down separately by making a vertical incision approximately 1 cm medial to the bicipital groove and carefully “teasing” the subscapularis off the underlying capsule (Fig. 2-22)

• Traction sutures are placed in the subscapularis, and a small elevator is used to assist in the dissection

• The leash of humeral circumflex vessels at the inferior border of the subscapularis should be identified and either protected or coagulated and tied off for this approach and the previous approach

• A capsulotomy can be made in a variety of fashions depending on the intended procedure (e.g., a T-capsular shift is made with a longitudinal incision over the humerus or glenoid and a horizontal incision in the middle of the capsule)

• The subscapularis can be split in a horizontal direction (Fig. 2-23)

• This maneuver provides limited access to the capsule and glenohumeral joint but can be used for coracoid bone block transfers or a modified capsulorrhaphy

Bony exposure

• Identify the bicipital groove

• Use a 2-mm drill to create four holes in the medial aspect of the groove

• Using a wide osteotome, create a flat osteotomy of the lesser tuberosity extending from the bicipital groove toward the edge of the humeral head cartilage

Expose the glenoid

• Special forked and ring retractors can be used to expose the glenoid

• Capsular releases can be performed (dissecting the glenoid articular surface circumferentially) and may be required for total shoulder arthroplasty

Closure

Incision (Fig. 2-25)

Superficial Dissection

The deltoid is identified on the scapular spine

• The deltoid may be split in line with its fibers (Fig. 2-26)

• Alternatively, the deltoid can be retracted superiorly after detachment of the medial 2 cm of the deltoid origin

Deep Dissection

The interval between the infraspinatus and teres minor is identified

The infraspinatus is identified by three anatomic features

• Horizontal direction of muscle fibers

• Bipennate nature

• Fatty raphe that divides the muscle belly

Typically the interval between the infraspinatus and teres minor is developed by blunt dissection and the posterior capsule is exposed by retraction of these muscles (Fig. 2-27)

• Alternatives include taking down the infraspinatus from its humeral insertion or splitting the two heads of the infraspinatus and using this interval

Do not dissect below the teres minor muscle because of risk to the axillary nerve and posterior humeral circumflex artery

• Fat may be present at the inferior border of the teres minor to help identify that you have gone too low

When performing a glenoid osteotomy, the suprascapular nerve should be identified by dissection and palpation 0.5 to 2 cm medial to the glenoid neck

Closure

Positioning

Incision (Fig. 2-28)

Superficial Dissection

The deep deltoid fascia is identified along with the anterolateral corner of the acromion (Fig. 2-29)

• The deltoid is detached and split

• Subperiosteally elevate the deltoid from the anterolateral acromion and acromioclavicular joint

• High-strength sutures are placed in the deltoid to aid in retraction and for later repair (Fig. 2-30)

• The deltoid can be split at the anterolateral border of the acromion (raphe) and extended 2 to 3 cm distally for exposure for rotator cuff repair

• A stay stitch may be placed distally in the deltoid to prevent iatrogenic injury to the deltoid from inadvertent distal splitting

Deep Dissection

The coracoacromial ligament, subacromial bursa, and supraspinatus tendon are now identified (Fig. 2-31)

• The coracoacromial ligament can be incised, protected, or tagged, depending on the surgical plan

• The supraspinatus tendon and overlying bursa are exposed and explored by rotating the arm

• The humeral head may be seen if a rotator cuff tear is present (Fig. 2-32)

Positioning

Incision

A 2- to 3-cm saber-type incision is made in Langer’s lines directly over the AC joint (Fig. 2-37)

• If an anterior portal is used, it often can be extended superiorly for this approach

• For AC reconstruction procedures, the incision is placed more medially and can be extended more distally to allow access to the coracoid (Fig. 2-38)

Superficial Dissection

Subperiosteally dissect the deltoid and trapezius attachments off the distal clavicle (Fig. 2-39)

Closure

Positioning

Incision

A 6-cm longitudinal incision is made just anterior (superior) and parallel to the spine of the scapula (Fig. 2-41)

Superficial Dissection

The trapezius muscle is identified and reflected anteriorly, off the spine of the scapula (Fig. 2-42)

Deep Dissection

Expose the supraspinatus muscle deep to the trapezius

• A layer of fat is usually present below the trapezius, and the fiber orientation is different (trapezius fibers are oblique, and supraspinatus fibers go directly from medial to lateral)

• Retract the supraspinatus anteriorly

• Expose the suprascapular notch (Fig. 2-43)

• Palpate the coracoid base and then palpate approximately 1 cm medially to locate the notch

• The suprascapular ligament is dissected

• This ligament may be covered with fat

• The suprascapular artery must be identified and protected

Closure

Positioning

Incision

A 5- to 8-cm longitudinal incision is made just superior and parallel to the clavicle (Fig. 2-44)

A smaller oblique incision can be made in Langer’s line if only limited exposure is required (Fig. 2-45)

• Can be used for intramedullary fixation of the clavicle

• Can limit injury to the suprascapular cutaneous nerves

Superficial or Deep Dissection

The deltotrapezial fascia is subperiosteally stripped off the clavicle (Fig. 2-46)

• Dissection is continued the amount necessary for reduction and fixation

Closure

Positioning

Incision

An 8- to 12-cm incision is made along the lateral border of the biceps

A deltopectoral incision can be extended distally for this incision (Fig. 2-47)

Superficial Dissection

Develop the interval between the biceps and the brachialis (Fig. 2-48)

Alternatively, split the brachialis (which has two nerves)

Deep Dissection

Closure

Positioning

Incision (Fig. 2-49)

Superficial Dissection

Make an incision in the fascia in line with the skin incision

Identify and separate the lateral and long head of the triceps (Fig. 2-50)

• The interval is more obvious proximally as the tendons merge distally

Deep Dissection

The medial (deep) head is exposed and split (Fig. 2-51)

• The radial nerve passes from medial to lateral in the upper/middle portion of the field and should be identified and protected

Closure

Positioning

Visualization of Structures

(Fig. 2-57)