Anterior Approach to Humerus Shaft

Anterior Approach to Humerus Shaft is used to treat the following conditions:

1. Open reduction and internal fixation of humerus shaft fractures.
2. Humeral tumor biopsy/resection.
3. Humeral osteotomy.
4. Treatment of osteomyelitis.

Position of the Patient

Place the patient supine on the operating table, with the arm on an arm board, abducted about 60 degrees.

Landmarks and Incision

Landmarks:

• The Coracoid process.
• The long head of the biceps brachii muscle.

Incision:

Make a curved incision from the tip of the coracoid process distally in line with deltopectoral groove along the lateral aspect of the humerus. Incision should be stopped approximately 5 cm above the flexion crease of the elbow (lateral antebrachial cutaneous nerve is at risk here).

Internervous plane

Proximally the Internervous plane in Anterior Approach to Humerus Shaft lies between:

1. Deltoid muscle which is innervated by the the axillary nerve.
2. Pectoralis major muscle which is innervated by the the medial and lateral pectoral nerves.

Distally the Internervous plane in Anterior Approach to Humerus Shaft lies between:

1. Medial brachialis muscle which is innervated by the the musculocutaneous nerve.
2. Lateral brachialis muscle which is innervated by the the radial nerve.

Superficial dissection

Identify the cephalic vein – can be taken medially or laterally.

Proximally, develop the interval between the deltoid and pectoralis major muscle.

Distally, incise the deep fascia of the arm in line with the skin incision.

Identify the interval between the biceps muscle and brachialis muscle, biceps muscle can be retracted medially or laterally (typically it’s taken medially).

Deep dissection

Proximally, incise the periosteum lateral to the pectoralis major tendon insertion, staying lateral to the long head of the biceps tendon, the anterior humeral circumflex artery is seen here and must be ligated.

Distally, the fibers of the brachialis are split longitudinally along the midline to expose the periosteum and humeral shaft.

Approach Extension

Proximal Extension: Because the anterior approach uses the deltopectoral interval, its upper end can be modified easily into an anterior approach to the shoulder (Deltopectoral approach).

Distal Extension: The anterior approach to humerus shaft cannot be extended distally.

Dangers

Structures at risk during anterior approach to humerus include:

1. Anterior circumflex humeral artery: The Anterior circumflex humeral artery is at risk proximally between the pectoralis major and deltoid muscles.
2. Axillary nerve: The Axillary nerve can be injured with vigorous retraction of the deltoid.
3. Radial nerve: The Radial nerve must be identified before any incision is made into the brachialis muscle or before periosteal elevation of the brachialis muscle off the humerus occurs. It’s also at risk on the middle 1/3 of the humerus where it lays in the spiral groove on the posterior humerus.

References

• Surgical Exposures in Orthopaedics book – 4th Edition
• Campbel’s Operative Orthopaedics book 12th