Anterior Approach to Shoulder

- See:

Positioning and Draping:

  • supine or beach chair;
  • small soft bolster is placed beneath the shoulder blades to protract the shoulder;
  • head is stabilized to prevent hyperextension and subsequent brachial plexus palsy;
  • place patient in a beach chair position w/ torso flexed 45 deg and the knees flexed to 30 deg;
    • in the beach chair position, ensure that the patient is firmly fastened to prevent sliding;
  • move patient to the edge of the table (operative side), and use a McConnel positioner to prevent the patient from failing off the table;
    • positioning is optimal when the scapula hangs over the edge of the table;
  • place a folded towel under the spine and ipsilateral scapula;
  • it is helpful to drape the should w/ a large Ioband sheet w/ a hole cut in the middle;
    • several Iobrand strips (2-3 inches in width) are also helpful;
      • consider the Mconnel Shoulder Positioner;

Instruments:

Superficial Dissection:


Deep Dissection:

  • clavipectoral fascial incision:
    • once the deltopectoral interval has been fully developed, the clavipectoral fascia is exposed (which is most prominent lateral to coracoid muscles);
    • clavipectoral fascia is differentiated from the deeper tissues, because it will not move with internal and external rotation;
    • tip of the coracoid and the conjoined tendon (short head of biceps and the coraco-brachialis) is identified;
    • clavipectoral fascia is then divided vertically just lateral to the conjoined tendon, up to coracoacromial ligament, exposing subscapularis tendon & lesser tuberosity.
      • proximally, the fascia is divided at a point just lateral to the coracoid;
      • the incision is carried distally to the level of the anterior circumflex;
      • these vessels mark the level of the subscapularis tendon;
  • identification of the musculocutaneous nerve:
    • musculocutaneous nerve can usually be palpated on deep surface of coracobrachialis;
    • nerve enters posterior of coracobrachialis about 5 cm distal to coracoid tip but can be as close as 1 to 2 cm;
  • identification of the axillary nerve
  • retraction:
    • often a "Charnley type" of self retaining retractor is inserted underneath the deltoid medially and the coracobrachialis laterally;
  • coraco-acromial ligament:
    • in patients w/ traumatic arthritis or DJD, the shoulders may be tight and therefore, the ligament can be
      partially incised for better exposure of the upper portion of the subscapularis;
    • in patients w/ rheumatoid arthritis or cuff tear arthropathy, excision of the CA ligament may destabilize the shoulder arthroplasty;

Transection of the Subscapularis:

  • subscapularis tendon and the underlying joint capsule are divided approximately 1 cm medial to the lesser tuberosity;
  • medial retraction of the tendon and capsule will expose the glenoid;

Caspsular Transection:

  • external rotation of the humerus affords better capsular exposure and relaxes the nerve;
  • insert a blunt retractor inferiorly to protect the axillary nerve, insert two single pronged skin hooks to elevate the capsule superiorly and place it under tension;
  • vertically transect the capsule at a point midway between the lesser trochanter and the edgle of the glenoid;
  • carry this vertical capsular incision superiorly into the rotator interval, which converts the capsular incision into a T (since the rotator interval lies in a horizontal direction);
  • at the end of the case, the superior and inferior capsular capsular flaps are closed (and shortened) in order to shift the inferior capsule in a superior direction;
  • the vertical portion of the incision is closed anatomically (so that there will be no loss of external rotation);

Distal Exposure:

  • lower part of shaft is exposed by incising brachialis longitudinally along lateral border of biceps;
  • lowest part of the front of the shaft can be approached between brachioradialis which is retracted laterally and brachialis which is retracted medially



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, February 28, 2017 1:55 pm