- Deltopectoral approach to the proximal humerus
The (anterior) deltopectoral approach can be used for almost any proximal humeral fracture treatment and is often the preferred approach.
This approach is also highly recommend for revision surgery.
The course of the following neurovascular structures should be kept in mind:
- Cephalic vein
- Anterior circumflex humeral artery
- Ascending branch of the anterior circumflex humeral artery
- Posterior circumflex humeral artery
- Musculocutaneus nerve
- Axillary nerve
Further neurovascular structures, eg, the brachial plexus, are only at risk if there is a rigorous retraction.
Anatomical landmarks for the anterior deltopectoral approach are:
A) Coracoid process
B) Proximal humeral shaft (on the level of the axilla)
Both landmarks can easily be palpated.
Make a 12-14 cm long skin incision between the coracoid process and the proximal humeral shaft. The shape of the skin incision can be straight or curved depending on surgeon’s preference.
For an arthroplasty, a rather vertical incision may be preferred (dashed line).
Exposure of deltopectoral groove and cephalic vein
Expose the deltopectoral groove with the cephalic vein. These structures can be identified by:
- The course of the muscle fibers
- The cephalic vein itself
- Fat tissue surrounding the vein
If in doubt, look for the deltopectoral groove at the proximal and/or distal end of the skin incision. (The sulcus is slightly more pronounced and in cases of revision surgery less scared.)
Dissection down to the deltopectoral groove
Retract the cephalic vein laterally or medially, and open along the groove. If retracted laterally, the anatomical drainage of blood from the deltoid muscle is respected but it is at risk of damage by retractors during surgery. In any case, the cephalic vein should be preserved in order to reduce the surgical edema of the limb.
Failure to find the deltopectoral groove can lead to difficulty in dissection of the deltoid and possibly to denervation of the anterior portion of the deltoid.
Bluntly dissect between and under the deltoid and pectoralis muscles down to expose the clavipectoral fascia.
Identify the coracoid process and the conjoined tendon.
Incise the clavipectoral fascia lateral to the conjoined tendon and inferior the coracoacromial ligament.
Retract the deltoid muscle laterally using a delta (modified Hohmann) retractor and the conjoint tendon medially using a Langenbeck retractor. The musculocutaneous nerve enters the coracobrachialis muscle as close as 2.5 cm distal to the tip of the coracoid. Retractors placed under the conjoined tendon can cause neuropraxia; therefore vigorous retraction must be avoided.
Expose the proximal humerus and confirm the anatomical landmarks (subscapularis tendon, lesser tuberosity, bicipital groove with the bicipital tendon and the greater tuberosity). Evaluate the fracture morphology. Hemorrhagic bursa tissue has to be resected if needed.
Distally, expose the pectoralis major.
Pitfall: axillary nerve damage
Be aware of retractor positioning (Roux or Hohmann retractor) in order to prevent iatrogenic damage of the axillary nerve.
- Using an additional delta retractor might be helpful to increase exposure of the proximal humerus.
- Exposure may be increased additionally by partially releasing the insertions of deltoid and/or pectoralis major.
- Shoulder abduction decreases tension on the deltoid, and makes it easier to retract laterally.
Anterior shoulder arthrotomy
Satisfactory reduction of anatomical neck fractures (eg, C1.3 or C3.1) may require an anterior shoulder arthrotomy. Access is improved by doing an osteotomy of the coracoid process to allow reflection of the coraco-brachialis and biceps muscles. Drill the coracoid first for later fixation.
Take care regarding the musculocutaneous nerve and underlying brachial plexus. Avoid excessive traction.
The subscapularis tendon is identified and divided vertically lateral to the musculotendinous junction. Remember the axillary nerve just distal to the subscapularis and medial to the proximal humerus.
Reflect the subscapularis from the underlying joint capsule and enter the joint through a vertical capsulotomy, medial to the lateral stump of subscapularis.
The arthrotomy is repaired by suture closure of the capsule and then the subscapularis. The coracoid is repaired with a screw or sutures placed through the drill hole.
Irrigate the wound. Placement of a drainage underneath the deltoid muscle might be considered.
Close the deltopectoral groove, the subcutaneous tissues and the skin.