Two

 

The Humerus

 

 

 

Anterior Approach to the Humeral Shaft

Minimally Invasive Anterior Approach to the Humeral Shaft Posterior Approach to the Humerus

Anterolateral Approach to the Distal Humerus Lateral Approach to the Distal Humerus Medial Approach to the Distal Humerus Applied Surgical Anatomy of the Arm

Operations on the humerus are relatively infrequent and generally involve the open reduction and internal fixation of fractures. All approaches to the humerus are potentially dangerous because the major nerves and vessels at this site run much closer to the bone than they do elsewhere in the body; the axillary, radial, and ulnar nerves all have a direct relationship to the humerus. Of these structures, the radial nerve is at greatest risk during exposure of the humeral shaft (see Fig. 2-39).

Six approaches to the humerus are described in this chapter: Three approaches, the anterior approach to the humerus, the minimally invasive

anterior approach to the humeral shaft, and the posterior approach, allow access to large portions of the bone. Three approaches, the anterolateral approach to the distal humerus, the lateral approach to the distal humerus, and the medial approach to the distal humerus, are designed for access to the distal third of the bone and its related structures.

The anterior and posterior approaches are the most versatile. The anterolateral approach to the distal humerus is extensile both proximally and distally, but this facility is rarely required. The lateral approach to the distal humerus is a strictly local approach to the common extensor origin and adjacent structures. The medial approach to the distal humerus is used in surgery for isolated fractures of the medial column of the distal humerus. Because the key surgical structure of the area (the radial nerve) courses down the arm in both the anterior and posterior compartments, the surgical anatomy of the humerus is described in a single section of this chapter, immediately after the description of the operative approaches.

 

Anterior Approach to the Humeral Shaft ‌

The anterior approach exposes the anterior surface of the shaft of the humerus.1–3 Normally, only a portion of the approach is needed for any one procedure. As in all approaches to the humerus, the radial nerve is the structure at greatest risk during surgery.

The uses of the anterior approach include the following:

1. Internal fixation of fractures of the humerus

2. Treatment of delayed or nonunion of humeral shaft fractures

3. Osteotomy of the humerus

4. Biopsy and resection of bone tumors

5. 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°. Tilt the patient away from the affected arm to reduce bleeding. Most surgeons prefer to sit facing the patient’s axilla, with the surgical assistant on the opposite side of the arm. Do not use a tourniquet; it will only get in the way (Fig. 2-1).

 

 

Figure 2-1 Place the patient supine on the operating table. Place his or her arm on an arm board and abduct the arm about 60 degrees.

 

 

 

Figure 2-2 For an anterior approach, make a longitudinal incision from the tip of the coracoid process distally in line with the deltopectoral groove and continue along the lateral aspect of the shaft of the humerus. Extend the incision as far distally as necessary, stopping about 5 cm above the flexion crease of the elbow. Palpate the coracoid process in a lateral to medial direction (inset).

Landmarks and Incision

Landmarks

Palpate the coracoid process of the scapula immediately below the junction of the middle- and outer-thirds of the clavicle (Fig. 2-2, inset).

Palpate the long head of the biceps brachii as it crosses the shoulder and runs down the arm. The lateral border of its freely moving muscular belly lies on the anterior surface of the arm.

Incision

Begin a longitudinal incision over the tip of the coracoid process of the scapula. Run it distally and laterally in the line of the deltopectoral groove to the insertion of the deltoid muscle on the lateral aspect of the humerus, about halfway down its shaft. From there, continue the incision distally as far as necessary, following the lateral border of the biceps muscle. The incision should be stopped about 5 cm above the flexion crease of the elbow (see Fig. 2-2).

 

Internervous Plane

 

The anterior approach makes use of two different internervous planes (Fig. 2-3A). Proximally, the plane lies between the deltoid muscle (which is supplied by the axillary nerve) and the pectoralis major muscle (which is supplied by the medial and lateral pectoral nerves). Distally, the plane lies between the medial fibers of the brachialis muscle (which are supplied by the musculocutaneous nerve) medially and the lateral fibers of the brachialis muscle (which are supplied by the radial nerve) laterally (Fig. 2-3B).

 

Superficial Surgical Dissection

Proximal Humeral Shaft

Identify the deltopectoral groove using the cephalic vein as a guide (Fig. 2-4, inset), and separate the two muscles, retracting the cephalic vein either medially with the pectoralis major or laterally with the deltoid, whichever is easier. Develop the muscular interval distally down to the insertion of the deltoid into the deltoid tuberosity and the insertion of the pectoralis major into the lateral lip of the bicipital groove (Fig. 2-4). Take care when retracting the deltoid; overzealous use of the retractor may paralyze the anterior half of the muscle by causing a compression injury to the axillary nerve.

Distal Humeral Shaft

Incise the deep fascia of the arm in line with the skin incision. Identify the muscular interval between the biceps brachii and the brachialis. Develop the interval by retracting the biceps medially. Beneath it lies the anterior aspect of the brachialis, which cloaks the humeral shaft (Fig. 2-5; see Fig. 2-4). At the very distal end of the incision the lateral cutaneous nerve of the forearm which is the terminal branch of the musculocutaneous nerve pierces the deep fascia on the lateral border of the biceps. If the incision is carried to its distal extent, identify and preserve this nerve.

 

 

 

Figure 2-3 Internervous plane. A: Proximally, the plane lies between the deltoid (axillary nerve) and the pectoralis major (medial and lateral pectoral nerves). B: Distally, the plane lies between the medial fibers of the brachialis (musculocutaneous nerve) medially and the lateral fibers of the brachialis (radial nerve) laterally.

 

 

Figure 2-4 Identify the deltopectoral groove, using the cephalic vein as a guide (inset). Develop the muscular interval down to the insertion of the deltoid into the deltoid tuberosity and the insertion of the pectoralis major into the lateral bicipital groove. Distally, incise the deep fascia in line with the skin incision to identify the interval between the biceps brachii and the brachialis.

 

Deep Surgical Dissection

Proximal Humeral Shaft

To expose the upper part of the shaft of the humerus, incise the periosteum longitudinally just lateral to the insertion of the tendon of the pectoralis major. Continue the incision proximally, staying lateral to the tendon of the long head of the biceps. The anterior circumflex humeral artery crosses the field of dissection in a medial to lateral direction and must be ligated (see Fig. 2-5). To expose the bone fully, you may need to detach part or all of the insertion of the pectoralis major muscle from the lateral lip of the bicipital groove of the humerus (Fig. 2-6). This must be done subperiosteally. Only detach the minimum amount of soft tissue to allow accurate visualization and reduction of the fracture. Try to preserve as much soft-tissue attachment as possible. If you need to dissect further around the bone, this dissection should remain in a strictly subperiosteal plane to avoid damage to the radial nerve, which lies in the spiral groove

of the humerus and crosses the back of the middle third of the bone in a medial to lateral direction (Fig. 2-7). Avoid the use of lever type retractors inserted around the bone as they may compress the nerve in its groove.

In extreme proximal humeral fractures, especially comminuted fractures, the head and anatomic neck of the humerus may need to be exposed. To accomplish this, the subscapularis muscle must be divided, with care taken to coagulate the triad of vessels that runs along the lower border of that muscle (Fig. 2-8; see Fig. 1-20). Frequently, however, the lesser tuberosity with the attached subscapularis tendon forms a separate fracture fragment, rendering division of the subscapularis tendon unnecessary.

Distal Humeral Shaft

Spiral fractures of the distal third of the humerus may be associated with radial nerve palsies and the spike of the distal fracture fragment may have the nerve wrapped around it.4 For this reason, in such cases it is safest to identify the radial nerve just above the elbow joint by gently opening up the intermuscular plane between the brachialis and the brachioradialis muscles before developing the intermuscuscular plane between bracialis and biceps brachii. This plane between brachialis and brachioradialis is oblique with brachioradialis overlying the brachialis muscle. Carefully follow the nerve proximally until it penetrates the lateral intermuscular septum. Then split the fibers of the brachialis longitudinally along its midline a safe distance from the nerve to expose the periosteum on the anterior surface of the humeral shaft. Strip the brachialis off the anterior surface of the bone. Try to preserve as much soft-tissue attachment as possible. To make the task easier, flex the elbow to take tension off the brachialis. The bone is now exposed (see Fig. 2-6).

 

Figure 2-5 Retract the biceps medially, being careful to identify the musculocutaneous nerve. Proximally, identify the anterior circumflex humeral artery as it crosses the field of dissection in a medial to lateral direction.

 

 

 

Figure 2-6 Proximally, detach the insertion of the pectoralis major from the lateral bicipital groove and then continue dissection subperiosteally to expose the upper portion of the humerus. Distally, split the fibers of the brachialis to expose the periosteum of the anterior humerus. Incise the periosteum, and strip the brachialis off the bone. Flexion of the elbow will take tension off the brachialis, making the exposure easier.

 

 

 

Figure 2-7 The radial nerve is vulnerable at two points as it courses along the humerus: one, in the spiral groove, and two, as it pierces the lateral intermuscular septum to run between the brachioradialis and the brachialis.

 

 

Figure 2-8 Proximal extension of the exposure. Using the deltopectoral interval, cut the tip of the coracoid and incise the subscapularis to provide an anterior approach to the shoulder.

 

 

Dang

 

 

Nerves

The radial nerve is vulnerable at the following two points:

1. In the spiral groove on the back of the middle third of the humerus. Do not stray onto the posterior surface of the bone (see Figs. 2-7 and 2-43). Remember that the radial nerve may be damaged by drills, taps, or screws that are inserted anteroposteriorly when anterior plates are being applied in the middle third of the bone. Take great care not to overpenetrate the posterior cortex when applying an anterior plate. Do not use lever type retractors placed around the bone.

2. In the anterior compartment of the distal third of the arm. At this point, the nerve has pierced the lateral intermuscular septum and lies between the brachioradialis and brachialis muscles. Note that this plane is oblique and not vertical (see Fig. 2-43). To avoid damaging the nerve, identify it before splitting the brachialis along its midline; the lateral portion of the muscle then serves as a cushion between the retractors that are being used in the exposure and the nerve itself (see Figs. 2-7 and 2-43).

The axillary nerve, which runs on the underside of the deltoid muscle, may be damaged as a result of a compression injury caused by overly vigorous retraction of the muscle. Care should be taken when the retractors are being positioned on the deltoid to avoid injuring the nerve (see Fig. 2-4).

The lateral cutaneous nerve of the forearm pierces the deep fascia just above the level of the elbow crease. It may be at risk if the dissection between biceps and brachialis is carried out to the distal extent of the approach.

Vessels

The anterior circumflex humeral vessels cross the operative field in the interval between the pectoralis major and deltoid muscles in the upper third of the arm. Because cutting these vessels cannot be avoided, they should be ligated or subjected to diathermy (see Figs. 2-5 and 2-6).

 

How to Enlarge the Approach

Local Measures

Flexion of the elbow relaxes both the brachialis and the biceps brachii, facilitating retraction of these muscles.

Extensile Measures

 

Proximal Extension. Because the anterior approach uses the deltopectoral interval, its upper end can be modified easily into an anterior approach to the shoulder (see Fig. 2-8).

 

Distal Extension. The anterior approach cannot be extended distally.

 

Minimally Invasive Anterior Approach to the Humeral Shaft‌

 

 

The minimally invasive anterior approach to the humerus utilizes two soft-tissue windows, proximal and distal that are the proximal and distal portions of the anterolateral approach to the humerus described earlier in this chapter. An alternative proximal approach using a deltoid split will not be described in this section. The use of this approach is almost exclusively for internal fixation of fractures of the humerus. The advantage of this

approach is the preservation of the blood supply to the fracture zone. The disadvantage is that the fracture is not exposed, which makes reduction more difficult to achieve and assess as well as exposing both patient and surgeon to radiation.5–9

 

Position of the Patient

 

Place the patient supine on the operating table in the same position as for the anterior approach to the humerus (see Fig. 2-1). Ensure that you can obtain adequate x-ray images of the pathology to be treated before prepping and draping. Use the best possible radiation protection for the patient and surgical team. Do not use a tourniquet.

 

Landmarks and Incision

Landmarks

Palpate the coracoid process of the scapula immediately below the junction of the middle and outer thirds of the clavicle (see Fig. 2-2, inset) and the lateral border of the biceps brachii (Fig. 2-9).

Incision

Make a 5- to 7-cm longitudinal incision beginning just below the coracoid process running down the arm in the line of the deltopectoral groove. Make a second 5- to 7-cm longitudinal incision overlying the lateral border of the biceps brachii in the distal third of the arm. The exact positioning of the incisions are determined by the site of the fracture.

 

Internervous Plane

 

Proximally, the anterior minimally invasive approach utilizes the plane between the deltoid muscle (axillary nerve) and the pectoralis major muscle (lateral and medial pectoral nerves). Distally, the plane lies between the medial half of the brachialis muscle supplied by the musculocutaneous nerve and the lateral half of the brachialis muscle supplied by the radial nerve (see Figs. 2-3 and 2-4).

 

 

Figure 2-9 Proximally make a 6- to 8-cm longitudinal incision overlying the deltopectoral groove. Distally make a 6- to 8-cm incision overlying the lateral border of the biceps brachii. The precise length and positioning of the incisions depends on the site of the pathology and the implant used to treat it.

 

Superficial Surgical Dissection

Proximal Window

Identify the deltopectoral groove, using the cephalic vein as a guide. Separate the two muscles. This can usually be done with blunt dissection (see Fig. 2-4). Retract the vein either laterally or medially and try to preserve it if possible.

Distal Window

Incise the deep fascia of the arm in the line of the skin incision and identify the muscular interval between the biceps brachii and the brachialis. Develop this interval by retracting the biceps medially and identify the brachialis muscle covering the anterior humeral shaft (Figs. 2-10 and 2-11).

 

Deep Surgical Dissection

Proximal Window

Develop the plane between the deltoid and the pectoralis major down to the bone. Stay lateral to the tendon of the long head of the biceps. For

access to the bone for plate application, detach part or all of the insertion of pectoralis major and part of the insertion of the deltoid.

Distal Window

Split the fibers of the brachialis longitudinally and develop an epiperiosteal plane between the deep surface of the brachialis and the periosteum covering the anterior surface of the humerus. Try to preserve as much of the soft tissue as possible. To make your task easier, flex the elbow to decrease the tension on the brachialis muscle.

 

 

 

Figure 2-10 Deepen the incision in the line of the skin incision. Proximally expose the deltopectoral interval. Distally expose the lateral border of the biceps brachii.

 

 

Figure 2-11 Proximally develop the interval between the pectoralis major muscle and the deltoid to expose the underlying bone. Part of the tendon of pectoralis major may need to be detached from the bone.

 

To connect the two windows, develop an epiperiosteal plane on the anterior surface of the humerus using your finger, a periosteal surfer, blunt elevator or the plate to be used. Begin distally and stick closely to the anterior surface of the bone. You may also need to develop this plane working distally through the proximal window (Figs. 2-12 and 2-13).

 

 

Dang

 

 

The radial nerve is lateral to the surgical approach in the distal window, lying between the lateral border of the brachialis and the brachioradialis. If the approach is used to treat a distal humeral fracture, identify the radial nerve as it lies between the brachialis and the brachioradialis muscles before starting the brachialis split to ensure that the nerve is well lateral to the deep dissection. In such fractures the nerve may be caught by the spike of bone on the distal fragment which will distort its position. If you wish to access the lateral column, develop a plane between the biceps and brachialis muscles medially and the brachioradialis, extensor carpi radialis longus, and brevis (the mobile wad of three) laterally.

 

 

Figure 2-12 Distally retract the belly of the biceps brachii muscle medially to expose the anterior surface of the brachialis muscle. Split the brachialis longitudinally in the line of its fibers to expose the anterior surface of the humerus. Next, develop an epiperiosteal plane on the anterior surface of the bone. Proximally develop an epiperiosteal plane on the anterior surface of the humerus using finger dissection.

 

 

Figure 2-13 Connect the proximal and distal windows by blunt dissection in an epiperiosteal plane on the anterior surface of the humerus.

 

The musculocutaneous nerve and its distal branch, the lateral cutaneous nerve of the forearm, lie medial to the brachialis and the distal window. To avoid damage to either nerve make sure that the brachialis is split in its midline.

Vessels

The anterior circumflex humeral vessels cross the operative field in the interval between the pectoralis major and the deltoid muscle in the upper third of the arm. These structures need to be identified while developing the plane and, if possible, avoided.

 

How to Enlarge the Approach

Local Measures

The minimally invasive anterior approach to the humerus can be converted into the anterior approach to the humerus by connecting the two skin incisions. Splitting brachialis completes the exposure.

 

Posterior Approach to the Humerus ‌

The midline posterior approach to the humerus is classically extensile, providing excellent access to the lower three-fourths of the posterior aspect of the humerus.1,10 As is true for all other approaches to the humerus, the posterior approach is complicated by the vulnerability of the radial nerve, which spirals around the back of the bone. The uses of this surgical approach include the following:

1. Open reduction and internal fixation of fractures of the humerus. In fractures in which the radial nerve is transected (classically displaced transverse fractures of the mid shaft of the humerus), this incision exposes the nerve as it traverses the back of the humerus.

2. Treatment of osteomyelitis

3. Biopsy and excision of tumors

4. Treatment of nonunion of fractures

5. Exploration of the radial nerve in the spiral groove

6. Insertion of retrograde humeral nails

 

Position of the Patient

 

Two positions of the patient are possible during surgery: a lateral position on the operating table with the affected side uppermost (Fig. 2-14A) or a prone position on the operating table with the arm abducted 90 degrees (Fig. 2-14B). A sandbag should be placed under the shoulder of the side to be operated on, and the elbow should be allowed to bend and the forearm to hang over the side of the table. A tourniquet should not be used because it will get in the way.

 

 

Figure 2-14 Position of the patient for the approach to the upper arm in either the

(A) lateral or (B) prone position.

 

Landmarks and Incision

Landmarks

The acromion is a rectangular bony prominence that forms the summit of the shoulder.

The olecranon fossa should be palpated at the distal end of the posterior aspect of the arm. Precise palpation is difficult, because the fossa is filled with fat and covered by a portion of the triceps muscle and aponeurosis. The fossa is filled by the olecranon when the elbow is extended.

Incision

Make a longitudinal incision in the midline of the posterior aspect of the arm, from 8 cm below the acromion to the olecranon fossa (Fig. 2-15).

 

Internervous Plane

 

There is no true internervous plane; dissection involves separating the heads of the triceps brachii muscle, all of which are supplied by the radial nerve. Because the nerve branches enter the muscle heads relatively near their origin and run down the arm in the muscle’s substance, splitting the

muscle longitudinally does not denervate any part of it. In addition, the medial head (which is the deepest head) has a dual nerve supply consisting of the radial and ulnar nerves; splitting the medial head longitudinally does not denervate either half (see Fig. 2-47).

 

Superficial Surgical Dissection

 

Incise the deep fascia of the arm in line with the skin incision (Fig. 2-16).

The key to superficial dissection lies in understanding the anatomy of the triceps muscle. This muscle has two layers. The outer layer consists of two heads: the lateral head arises from the lateral lip of the spiral groove, and the long head arises from the infraglenoid tubercle of the scapula. The inner layer consists of the third head, the medial (or deep) head, which arises from the whole width of the posterior aspect of the humerus below the spiral groove all the way down to the distal fourth of the bone. The spiral groove contains the radial nerve; thus, the radial nerve actually separates the origins of the lateral and medial heads (see Fig. 2-47).

To identify the gap between the lateral and long heads, begin proximally, above the point at which the two heads fuse to form a common tendon (Fig. 2-17). Proximally, develop this interval between the heads by blunt dissection, retracting the lateral head laterally and the long head medially. Distally, the muscle will need to be divided by sharp dissection along the line of the skin incision (Figs. 2-18; see Fig. 2-46). Many small blood vessels cross the muscle at this level; these need to be coagulated individually.

 

 

Figure 2-15 Make a longitudinal incision in the midline of the posterior aspect of the arm, from 8 cm below the acromion to the olecranon fossa.

 

Deep Surgical Dissection

 

The medial head of the triceps muscle lies below the other two heads; the radial nerve runs just proximal to it in the spiral groove (see Fig. 2-18). Incise the medial head in the midline, continuing the dissection down to

the periosteum of the humerus. Then, strip the muscle off the bone by epiperiosteal dissection (Fig. 2-19). The plane of operation must remain in an epiperiosteal location to avoid damaging the ulnar nerve, which pierces the medial intermuscular septum as it passes in an anterior to posterior direction in the lower third of the arm (see Figs. 2-19 and 2-48). Detach as little soft tissue as possible to preserve blood supply to the zone of injury.

 

 

Dang

 

 

Nerves

The radial nerve is vulnerable in the spiral groove. However, after it is identified, the nerve is safe. To avoid problems, never continue the dissection down to bone in the proximal two-thirds of the arm until the nerve has been identified positively (see Fig. 2-18).

The ulnar nerve lies deep to the medial head of the triceps in the lower third of the arm and may be damaged if that muscle is elevated off the humerus in anything but an epiperiosteal plane (see Fig. 2-48).

 

 

Figure 2-16 Incise the deep fascia of the arm in line with the skin incision.

 

 

Figure 2-17 Identify the gap between the lateral and long heads of the triceps muscle.

 

 

Figure 2-18 Proximally develop the interval between the two heads by blunt dissection, retracting the lateral head laterally and the long head medially. Distally split their common tendon along the line of the skin incision by sharp dissection. Identify the radial nerve and the accompanying profunda brachii artery.

 

Vessels

The profunda brachii artery lies with the radial nerve in the spiral groove and is similarly vulnerable (see Fig. 2-18).

How to Enlarge the Approach

Extensile Measures

 

Proximal Extension. The bone cannot be exposed effectively above the spiral groove using the posterior approach. At this point, the deltoid muscle (which is the outer layer of the musculature) also crosses the operative field. More proximal exposures should be accomplished by the anterior route.

 

Distal Extension. The skin incision can be extended distally over the olecranon; deepening the approach provides access to the elbow joint via an olecranon osteotomy (see Posterior Approach to the Elbow in Chapter 3; Figs. 2-20 and 2-21). Alternatively, identify and dissect out the ulna nerve. Develop a plane between the medial aspect of the triceps muscle and the bone to expose the medial supracondylar ridge of the humerus (Fig. 2-21D). Then develop a plane on the lateral aspect of the triceps between the tendon and the bone. Retract the muscle medially to expose the lateral supracondylar ridge of the humerus (Fig. 2-21C). Pass a sling underneath the triceps and retract the muscle medially and laterally to gain access to the whole of the posterior aspect of the distal humerus (Fig. 2-21E).

 

 

Figure 2-19 Incise the medial head of the triceps in the midline. Strip the muscle off the bone subperiosteally. The radial nerve, which runs just proximal to the origin of the muscle in the spiral groove, must be identified and preserved. The muscle must be stripped from the bone below the level of the periosteum to avoid damaging the ulnar nerve, which pierces the medial intermuscular septum. Preserve as much soft-tissue attachment to the bone as possible.

 

 

Figure 2-20 The incision can be extended distally over the olecranon to give access to the elbow joint via an olecranon osteotomy. Proximal extension cannot be used effectively above the spiral groove because of the position of the radial nerve.‌

 

 

 

 

Figure 2-21 (A) To extend the approach distally, extend the skin incision over the olecranon and subcutaneous border of the ulna. (B) Deepen the incision to expose

the triceps tendon. Identify and dissect out the ulnar nerve. (C) Develop a plane on the lateral aspect of the triceps muscle belly and tendon. Retract the muscle medially to expose the lateral supracondylar ridge of the humerus. (D) Develop a plane on the medial aspect of the triceps muscle belly and tendon. Retract the muscle laterally to expose the medial supracondylar ridge of the humerus. (E) Pass a sling underneath the triceps and retract the muscle medially and laterally to gain access to the whole of the posterior aspect of the distal humerus.

 

Anterolateral Approach to the Distal Humerus‌

 

 

This anterolateral approach exposes the distal fourth of the humerus. Its major advantage over the brachialis-splitting anterior approach is that it can be extended both distally and proximally, whereas the brachialis-splitting approach cannot be extended distally. Its uses include the following:

1. Open reduction and internal fixation of fractures of the distal half of the humerus, especially the Holstein Lewis fracture

2. Exploration of the radial nerve in the distal part of the arm

 

Position of the Patient

 

Place the patient supine on the operating table, with the arm lying on an arm board and abducted about 60 degrees. Exsanguinate the limb either by elevating it for 3 minutes or by applying a soft rubber bandage; then apply a tourniquet in as high a position as possible (see Fig. 2-1).

 

Landmarks and Incision

Landmarks

The landmarks in this approach are the biceps brachii muscle (see Applied Surgical Anatomy of the Anterior Approach in Chapter 1) and the flexion crease of the elbow.

Incision

Make a curved longitudinal incision over the lateral border of the biceps, starting about 10 cm proximal to the flexion crease of the elbow. Follow the contour of the muscle, ending the incision just above the flexion crease

of the elbow (Fig. 2-22).

 

Internervous Plane

 

There is no true internervous plane, because both the brachioradialis muscle and the lateral half of the brachialis muscle are supplied by the radial nerve proximal to the area of the incision. Proximal extension of the incision may denervate part of the brachialis, but this is of no clinical significance, because the radial nerve supply to the brachialis is minor and, probably, only proprioceptive. For this reason, the plane is both safe and extensile. Care should be taken during dissection down to the deep fascia; the lateral cutaneous nerve of the forearm runs roughly in the line of approach and should be retracted clear of the incision, in conjunction with the biceps (Figs. 2-23 and 2-24).

 

Superficial Surgical Dissection

 

Incise the deep fascia of the arm in line with the skin incision and identify the lateral border of the biceps (see Fig. 2-23). Retract the biceps medially to reveal the brachialis and brachioradialis (see Fig. 2-24). Next, identify the interval between these muscles just above the elbow, incise the deep fascia over them in line with the intermuscular interval, and develop the intermuscular plane (Fig. 2-25). Find the radial nerve between the two muscles at the level of the elbow joint by exploring this oblique intermuscular plane gently with a finger. This is the easiest point at which to find the nerve. (The elbow is the point at which the radial nerve should be identified in all surgery performed in this general area.) Take care not to stretch the radial nerve while manipulating fractures in this area to obtain a reduction. Retract the brachioradialis laterally and the brachialis and biceps medially. Trace the radial nerve proximally until it pierces the lateral intermuscular septum.

 

Deep Surgical Dissection

 

Carefully avoiding the radial nerve and staying on its medial side, incise the lateral border of the brachialis muscle longitudinally, cutting down to bone (Fig. 2-26). Incise the periosteum of the anterolateral aspect of the humerus longitudinally and retract the brachialis medially, lifting it off the anterior aspect of the bone by subperiosteal dissection. The anterior aspect of the distal humeral shaft now is exposed.

 

 

Figure 2-22 The incision for the anterior lateral approach. Make a curved longitudinal incision over the lateral border of the biceps, starting about 10 cm proximal to the flexion crease of the elbow. End the incision just above the flexion crease.

 

 

Figure 2-23 There is no true internervous plane, but both the brachioradialis and the lateral half of the brachialis are supplied well proximal to the incision by the radial nerve. The sensory branch of the musculocutaneous nerve, the lateral cutaneous nerve of the forearm (lateral antebrachial cutaneous nerve), is seen emerging between the biceps and brachialis muscles.

 

 

Dang

 

 

Nerves

The radial nerve must be identified and preserved before any incision is made through the substance of the brachialis muscle.

 

How to Enlarge the Approach

Extensile Measures

 

Proximal Extension. The incision can be extended proximally (although this rarely is required) by developing the plane between the brachialis medially and the lateral head of the triceps posterolaterally. Stripping brachialis from the front of the anterior aspect of the humerus exposes the bone. However, care must be taken if the dissection is taken further posteriorly, as posterior dissection may endanger the radial nerve as it

passes in the spiral groove. If the approach is therefore extended posteriorly, a subperiosteal plane must be used. The disadvantage of soft-tissue stripping of the bone is in this case outweighed by the need to reduce the risk of damage to the radial nerve (Fig. 2-27).

 

 

 

Figure 2-24 Retract the biceps medially. Identify the lateral cutaneous nerve of the forearm (the sensory continuation of the musculocutaneous nerve) and retract it with the biceps. Identify the interval between the brachialis and the brachioradialis.

 

 

Figure 2-25 Develop the intermuscular plane between the brachialis and the brachioradialis. Identify the radial nerve between the two muscles. Retract the brachioradialis laterally and the brachialis and biceps medially.Then trace the radial nerve proximally until it pierces the lateral intermuscular septum.

 

Alternatively develop a plane between the lateral intermuscular septum and the triceps muscle entering the posterior compartment of the arm. Internally rotate the shoulder. Follow the radial nerve through the lateral intermuscular septum dividing some of the septum to allow gentle mobilization of the nerve. Identify and preserve the posterior antebrachial cutaneous nerve which arises from the radial nerve. Gently retract the triceps posteriorly to expose the posterior surface of the humerus with the radial nerve lying in its spiral groove (follow the radial nerve proximally, posterior to the humerus and anterior to the triceps; Fig. 2-28). This allows safe exposure of the distal two-thirds of the humerus.

 

 

Figure 2-26 Incise the periosteum of the anterolateral aspect of the humerus, and retract the brachialis and the periosteum medially to expose the anterior aspect of the distal shaft of the humerus.

 

 

Figure 2-27 The incision can be extended proximally by developing the plane between the brachialis and the lateral head of the triceps. The radial nerve is seen piercing the intermuscular septum. Posterior dissection may endanger the nerve as it passes through the spiral groove unless the dissection is kept below the periosteum.

 

 

Figure 2-28 Develop a plane between the lateral intermuscular septum and the triceps muscle entering the posterior compartment of the arm. Follow the radial nerve through the lateral intermuscular septum dividing some of the septum to allow gentle mobilization of the nerve. Follow the radial nerve proximally, posterior to the humerus and anterior to the triceps.

 

Distal Extension. The anterolateral approach may be extended into an anterior approach to the elbow by continuing the skin incision distally and developing a plane between the brachioradialis muscle (which is supplied by the radial nerve) and the pronator teres muscle (which is supplied by the median nerve). Care should be taken to avoid the lateral cutaneous nerve of the forearm (the continuation of the musculocutaneous nerve), which emerges along the lateral side of the biceps tendon (see Anterolateral Approach in Chapter 3; see Figs. 3-24 and 3-25).

 

Lateral Approach to the Distal Humerus ‌

The lateral approach exposes the lateral epicondyle and the origin of the

wrist extensors. Its uses include the following:

1. Open reduction and internal fixation of fractures of the lateral condyle

2. Surgical treatment of tennis elbow (lateral epicondylitis)11,12

3. Repair of lateral supporting structures of elbow13

The lateral approach does not afford access to the lateral portion of the elbow joint except by extension. The joint itself should be accessed by the posterior, posterolateral, or anterolateral approach.

 

Position of the Patient

 

Place the patient supine on the operating table, with the arm lying across the chest. Exsanguinate the arm either by elevating it for 3 minutes or by applying a soft, thin rubber bandage or exsanguinator. Then, inflate the tourniquet (Fig. 2-29).

 

Landmarks and Incision

Landmarks

Palpate the lateral epicondyle on the lateral aspect of the distal arm. It is the smaller of the two epicondyles.

The lateral supracondylar ridge of the humerus is defined better and longer than is the medial supracondylar ridge. It extends almost to the deltoid tuberosity (Fig. 2-30).

Incision

Make a 4- to 6-cm curved or straight incision on the lateral aspect of the elbow over the lateral supracondylar ridge (see Fig. 2-30).

 

Internervous Plane

 

There is no true internervous plane, because both the triceps and the brachioradialis muscles are supplied by the radial nerve. Because the nerve supplies these muscles well proximal to the area of the surgical approach, the plane between them can be exploited distally without fear of damaging the nerve supply to either muscle (Fig. 2-31A).

 

Figure 2-29 Position of the patient on the operating table. Place the patient supine on the operating table with the arm lying across the chest.

 

 

 

Figure 2-30 Make a straight or curved incision over the lateral supracondylar ridge of the elbow.

 

 

 

Figure 2-31 A, B: Intermuscular plane between the triceps and brachioradialis

muscles. Both are supplied by the radial nerve proximal to the incision.

 

Superficial Surgical Dissection

 

Incise the deep fascia in line with the skin incision (Fig. 2-31B). Define the plane between the brachioradialis, which originates from the lateral supracondylar ridge, and the triceps, and cut between these muscles down to bone, reflecting the brachioradialis anteriorly and the triceps posteriorly (Fig. 2-32; see Fig. 2-50).

 

Deep Surgical Dissection

 

Identify the common extensor origin as it arises from the lateral epicondyle of the humerus (see Fig. 2-32). If further exposure of the bone is required, reflect the triceps off the back of the humerus. Release the extensor origin if a better view of the lateral epicondyle is needed (Fig. 2-32).

 

 

Dang

 

 

Nerves

The radial nerve pierces the lateral intermuscular septum in the distal third of the arm. It is safe as long as the approach is not extended proximally (see Fig. 2-52).

 

 

Figure 2-32 Incise the deep fascia in line with the skin incision. Define the plane between the brachioradialis and the triceps muscle and make an incision between them down onto the lateral supracondylar ridge. Reflect the brachioradialis anteriorly and the triceps posteriorly.

 

How to Enlarge the Approach

Extensile Measures

 

Proximal Extension. Proximal extension is not possible, because the radial nerve crosses the proposed line of dissection.

 

Distal Extension. The lateral approach can be extended to the radial head only by using the intermuscular plane between the anconeus muscle (which is supplied by the radial nerve) and the extensor carpi ulnaris muscle (which is supplied by the posterior interosseous nerve; see Posterolateral Approach to the Radial Head in Chapter 4; and see Fig. 2-

33). This approach cannot be extended further distally due to the presence of the posterior interosseous nerve winding round the neck of the proximal radius.

 

 

Figure 2-33 The incision may be extended to expose the radial head by using the internervous plane between the anconeus (radial nerve) and the extensor carpi ulnaris (posterior interosseous nerve). The common extensor origin is detached and reflected anteriorly. The triceps also may be reflected more posteriorly. Proximal extension is not possible because of the course of the radial nerve.

 

Medial Approach to the Distal Humerus ‌

The medial approach to the distal humerus is used to access the medial supracondylar ridge of the humerus, the common flexor/pronator muscle origin arising from the medial epicondyle, and the medial compartment of the elbow joint. The approach does not give such a good exposure of the joint as the medial approach to the elbow (see Anteromedial Approach to the Elbow in Chapter 3, page 118) but does not involve an osteotomy of the medial epicondyle.

Its uses include the following:

1. Open reduction and internal fixation of extra articular fractures of the

   medial column of the distal humerus

2. Surgical treatment of medial epicondylitis14

3. Repair or reconstruction of the ulnar collateral ligament of the elbow

4. Removal of loose body from medial compartment of elbow15,16

 

Position of the Patient

 

Two positions are available for use.

Place the patient prone on the operating table. Flex the elbow 90 degrees and place the forearm over the back. The forearm is in neutral rotation. In this position the medial epicondyle is directly facing the surgeon (Fig. 2-34).

 

 

 

Figure 2-34 Place the patient prone on the operating table. Flex the elbow 90 degrees and place the forearm in neutral rotation over the back.

 

Alternatively place the patient supine on the operating table with the arm supported on an arm board or table. Abduct the arm and rotate the shoulder fully externally so that the medial epicondyle of the humerus

faces anteriorly. Flex the elbow 90 degrees (Fig. 3-11).

Exsanguinate the limb either by elevating it for 5 minutes or by applying a soft rubber bandage (or exsanguinator). Then, inflate a tourniquet.

 

Landmarks and Incision

Landmarks

Palpate the medial epicondyle of the humerus, the large subcutaneous bony mass that stands out on the medial side of the distal end of the humerus. Above it palpate the medial supracondylar ridge of the humerus which is more difficult to feel being covered by muscles.

Incision

Begin 5 cm above the elbow joint centered over the medial supracondylar ridge of the humerus. Extend the incision distally passing over the medial epicondyle to end just below the elbow joint (Fig. 2-35).

Internervous Plane

The internervous plane lies between flexor/pronator group of muscles arising from the medial epicondyle supplied by the median and ulnar nerves and the triceps muscle supplied by the radial nerve (see Fig. 3-13).

 

Superficial Surgical Dissection

 

Deepen the approach through subcutaneous fat in the line of the skin incision. The posterior branch of the medial cutaneous antebrachial nerve crosses the operative line and should be identified and preserved to prevent troublesome postoperative neuroma formation (Fig. 2-36).

Palpate the ulnar nerve as it runs in its groove behind the medial epicondyle of the humerus. Incise the fascia over the nerve starting proximal to the medial epicondyle; then, isolate the nerve along the length of the incision.

 

Deep Surgical Dissection

 

Palpate the medial epicondylar ridge of the humerus. Release the medial intermuscular septum from the medial epicondylar ridge. This will allow you to visualize the bone and retract the flexor/pronator muscle origin to reveal the anterior capsule of the elbow and the anterior aspect of the medial side of the distal humerus joint (Figs. 2-37 and 2-38). Incise the

joint capsule longitudinally if access to the joint is required. This is rarely indicated.

 

 

 

Figure 2-35 Begin 5 cm above the elbow joint centered over the medial supracondylar ridge of the humerus. Extend the incision distally passing over the medial epicondyle to end just below the elbow.

 

 

 

Figure 2-36 Palpate the ulnar nerve as it runs in its groove behind the medial

epicondyle of the humerus. Incise the fascia over the nerve starting proximal to the medial epicondyle.

 

 

 

Figure 2-37 Palpate the medial epicondylar ridge of the humerus. Release the medial intermuscular septum from the medial epicondylar ridge.

 

 

 

Figure 2-38 Retract the flexor/pronator muscle origin to reveal the anterior capsule of the elbow and the anterior aspect of the medial side of the distal humerus.

Dang

 

 

Nerves

The posterior branch of the medial cutaneous antebrachial nerve crosses the operative field during the superficial surgical dissection. It should be identified and preserved.

The ulnar nerve needs to be identified and isolated before the incision is deepened down to the joint. High incidence of temporary ulnar nerve palsies have been reported in some ligament reconstructive procedures. Ensure that retraction of the nerve is kept to a minimum.

 

How to Enlarge the Approach

 

Proximal Extension. The approach cannot usefully be extended proximally. An anterolateral or posterior approach is advised if access to the middle third of the humerus is required.

 

Distal Extension. The approach can only be extended distally by performing an osteotomy of the medial epicondyle (see Anteromedial Approach to Elbow in Chapter 3, page 118). This distal extension may give access to the insertion of the brachialis into the coronoid but does not allow more distal exposure of the ulna.

 

Applied Surgical Anatomy of the Arm ‌

 

Overview

 

The critical neurovascular structures in surgery of the arm do not stay neatly in one operative field, but cross from compartment to compartment as they course down the arm. Therefore, it is easiest to view the anatomy of the arm as consisting of two major muscle compartments, flexor and extensor, that share responsibility for three major nerves and arteries (Fig. 2-39).

 

Muscle Compartments

1. The anterior flexor compartment contains three muscles: The coracobrachialis, the biceps brachii, and the brachialis. Two are flexors of the elbow; all are supplied by the musculocutaneous nerve.

2. The posterior extensor compartment consists of one muscle, the triceps brachii, which is supplied by the radial nerve. In the distal two-thirds of the arm, the muscle compartments are separated by lateral and medial intermuscular septa.

Nerves

1. The radial nerve, which is the key surgical landmark in the arm, is the continuation of the posterior cord of the brachial plexus. It begins behind the axillary artery at the shoulder, runs along the posterior wall of the axilla (on the subscapularis, latissimus dorsi, and teres major muscles), and then passes through the triangular space between the long head of the triceps muscle and the shaft of the humerus beneath the teres major muscle. In the arm, the nerve lies in the spiral groove on the posterior aspect of the humerus between the lateral and medial (deep) heads of the triceps muscle. After crossing the back of the humerus and giving off branches to the lateral head and the lateral part of the medial head of the triceps, the radial nerve pierces the lateral intermuscular septum, entering the anterior compartment. At this point, the nerve may be vulnerable to distal locking bolts inserted from the lateral side of the arm. The nerve lies between the brachioradialis and brachialis muscles as it crosses the elbow joint. There, it supplies the brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, and anconeus muscles (see Figs. 2-51 and 2-52). Although a radial nerve palsy is not uncommon following fractures of the humeral shaft, the vast majority of these are due to a neurapraxia. Exploration of the nerve is, therefore, not mandatory if a nerve palsy is present following fracture.17 The presence of a nerve palsy following reduction in a patient without an initial neurological lesion is a good indication for exploration as the nerve may have become trapped between the bony fragments during reduction.

    

    

   Figure 2-39 Schematic diagram of the upper arm. The compartments of the arm are shown. The muscles are removed partially to show the course of the radial, ulnar, and median nerves as they run down the arm. The relationships of the nerves to the compartments and septa are seen.

    

2. The median nerve remains in the anterior compartment, anteromedial to the humerus. It runs with the brachial artery, lateral to it in the upper arm and medial to it in the cubital fossa.

3. The ulnar nerve lies behind the brachial artery in the anterior

compartment of the upper half of the arm. It pierces the medial intermuscular septum about two-thirds of the way down the arm to enter the posterior compartment, where it lies with the triceps muscle. It then travels on the back of the medial epicondyle of the humerus, where it is almost subcutaneous in location. Similar to the median nerve, it has no branches in the arm (see Figs. 2-43, 2-49, and 2-51).

Arteries

The vascular organization of the arm is relatively simple; each nerve takes one artery with it.

1. The brachial artery runs with the median nerve down the medial border of the arm under the biceps brachii muscle and onto the brachialis muscle. The artery can be palpated along its entire length, because the deep fascia of the arm is the only medial covering. The artery lies medial to the humerus in the upper two-thirds of the arm. At the elbow, it curves laterally to lie over the anterior surface of the bone, where it may be damaged in supracondylar fractures of the humerus (Figs. 2-40 and 2-41).

    

    

    

   Figure 2-40 Superficial layer of muscles of the arm. Note the course of the brachial artery and the median and ulnar nerves. The brachial artery starts medial to the median nerve. In the distal part of the arm, it moves lateral to the median nerve before entering the cubital fossa.

    

    

   Figure 2-41 The anterior fibers of the deltoid have been removed. The pectoralis major and minor have been resected at their insertions. Note the relationship of the nerves to the teres major, subscapularis, and latissimus dorsi, as well as the point where the musculocutaneous nerve enters the coracobrachialis muscle. Distally, note the position of the brachial artery and median nerve at the tendinous insertion of the biceps.

    

2. The profunda brachii artery runs with the radial nerve, supplying the triceps brachii muscle (see Figs. 2-47 and 2-48).

3. The ulnar collateral artery runs with the ulnar nerve. The three arteries anastomose freely with one another around the elbow joint.

 

Landmarks and Incision

Incisions

A longitudinal incision on the anterior aspect of the arm closely parallels the relaxed skin tension line (lines of cleavage of the skin). More proximally, however, the same incision crosses perpendicular to the relaxed skin tension line. The cosmetic appearance of anterior scars, therefore, is variable and dependent on their location.

A longitudinal incision on the posterior aspect of the humerus crosses the relaxed skin tension lines at almost 90 degrees. Scars made by posterior incisions are likely to be broad.

Superficial Surgical Dissection

Anterior Approach to the Humerus

Proximally, the internervous plane lies between the deltoid muscle (which is supplied by the axillary nerve) and the pectoralis major muscle (which is supplied by the lateral and medial pectoral nerves; see Anterior Approach in Chapter 1). Distally, the approach involves the muscles of the flexor compartment of the arm (Figs. 2-42 through 2-44; see Figs. 2-40 and 2-

41).

The coracobrachialis is a largely vestigial muscle arising from the coracoid process (see Applied Surgical Anatomy of the Anterior Approach in Chapter 1).

The biceps brachii is a powerful flexor of the elbow and supinator of the forearm (see Applied Surgical Anatomy of the Anterior Approach in Chapter 1).

The brachialis is the main elbow flexor, the workhorse of the upper arm. The biceps only really comes into play when extra strength or speed of flexion is required.

The surgical importance of the brachialis lies in its nerve supply. The lateral part of the muscle is supplied by the radial nerve, and the medial part is supplied by the musculocutaneous nerve. Thus, the muscle can be split longitudinally without either side being denervated. Because the musculocutaneous nerve is the major nerve supply to the brachialis, even cutting the radial nerve supply to the muscle seems to have little clinical effect. That is why the plane between the brachialis and the adjacent lateral muscle, the brachioradialis, is useful in surgery.

 

Posterior Approach to the Humerus

 

The posterior approach involves splitting the triceps brachii muscle (Figs. 2-45 through 2-49).

 

 

Figure 2-42 The biceps muscle has been removed at its proximal origins—its conjoined tendon and long head. A portion of the coracobrachialis has been removed to reveal the musculocutaneous nerve running on the brachialis muscle, supplying it. The median nerve and ulnar nerve course through the arm without supplying its muscles.

 

 

 

Figure 2-43 The central portion of the brachialis and the extensor carpi radialis longus have been resected to reveal the distal humerus and the course of the radial

nerve as it pierces the lateral intermuscular septum to enter the anterior compartment. The radial nerve continues distally into the elbow before entering the supinator muscle. Medially, the relationships of the median nerve, brachial artery, and ulnar nerve are revealed. The median nerve is anterior to the brachial artery. The ulnar nerve, situated posteriorly, penetrates the medial intermuscular septum to enter the posterior compartment of the arm. The partially resected flexor–pronator group reveals the deeper structures at the level of the elbow.

 

 

 

Figure 2-44 The origins and insertions of the muscles of the arm. Brachialis. Origin. Lower two-thirds of anterior surface of humerus. Insertion. Coronoid process and tuberosity of ulna. Action. Flexor of forearm. Nerve supply. Musculocutaneous and radial nerves.

 

 

Figure 2-45 The anatomy of the posterior aspect of the arm. Note the cleavage plane between the long and lateral heads of the triceps.

 

 

 

Figure 2-46 The most posterior portion of the deltoid muscle has been removed to reveal the origin of the lateral head of the triceps. Triceps Brachii. Origin. Long head from infraglenoid tuberosity of scapula. Lateral head from posterior and

lateral aspect of humerus. Medial (deep) head from lower posterior surface of humerus. Insertion. Upper posterior surface of olecranon. Action. Extensor of forearm. Weak adductor of shoulder. Nerve supply. Radial nerve.

 

 

 

Figure 2-47 The central portion of the lateral head of the triceps has been removed to reveal the courses of the radial nerve and profunda brachii artery in the spiral groove. The fibers of the lateral head of the triceps arise from the lateral lip of the spiral groove. The medial head arises from the medial side of the spiral groove. the nerve lies between these two muscle origins. Detail of the relationship among the radial nerve, the axillary artery, and the profunda brachii artery (inset). The axillary artery becomes the brachial artery on the anterior surface of the humerus. There it gives off a branch, the profunda brachii artery, which continues posteriorly with the radial nerve through the triangular interval and the spiral groove.

 

 

Figure 2-48 Resection of the proximal half of the triceps. The radial nerve and profunda brachii artery run in the spiral groove between the origins of the lateral and deep heads of the triceps. The nerve and vessel penetrate the lateral intermuscular septum before entering the anterior compartment of the arm. The ulnar nerve pierces the medial intermuscular septum to gain entrance to the posterior compartment of the arm.

 

 

Figure 2-49 The entire triceps muscle has been removed, uncovering the entire posterior surface of the humerus. The medial and lateral intermuscular septa and the nerves that penetrate them are seen.

 

 

Figure 2-50 The lateral aspect of the humerus, with the overlying superficial cutaneous nerves.

 

 

Figure 2-51 The posterior aspect of the humerus and elbow joint and the course of the ulnar nerve. The lateral intermuscular septum runs beneath the brachioradialis. The main continuation of the radial nerve is the posterior interosseous nerve, which pierces the supinator muscle through the arcade of Frohse.

 

 

Figure 2-52 The lateral intermuscular septum and the course of the radial nerve as it passes from the spiral groove through the intermuscular septum to emerge in the forearm from between the brachialis and the brachioradialis. The muscles covering the posterolateral aspect of the joint have been removed to reveal the joint capsule.

 

 

Figure 2-53 The muscles have been removed completely, showing the origins of the musculature of the posterior humerus.

 

The long head of the triceps brachii receives its radial nerve supply high up in the axilla, close to its origin; the lateral head receives its supply lower, at the upper level of the spiral groove. The two heads can be split up to the level of the spiral groove without compromising the nerve supply of either (see Fig. 2-53; see Figs. 2-45 through 2-49).

The medial (deep) head has a dual nerve supply. The medial half receives fibers from the ulnar nerve. These fibers originate from the radial nerve and run alongside the ulnar nerve, so closely bound to it that they once were thought of as branches of the ulnar nerve. They actually are radial fibers that are “hitchhiking” in the ulnar nerve substance.18

The lateral half of the medial head receives its nerve supply from the main trunk of the radial nerve as it crosses the back of the humerus in the spiral groove. Because of its dual nerve supply, the medial head may be split longitudinally to expose the posterior surface of the humerus.

 

Special Anatomic Points

 

In some patients, the coracobrachialis muscle has an additional head that attaches to the ligament of Struthers.19 This ligament connects a supracondylar spur of bone to the medial epicondyle of the humerus. It may trap the median nerve between itself and the underlying bone. Entrapment produces symptoms similar to those of carpal tunnel syndrome.20 Compression of the median nerve at this level can be differentiated from compression within the carpal tunnel because the flexor muscles of the forearm, as well as the palmar cutaneous branches of the median nerve, are affected. All these branches come off below the ligament and above the carpal tunnel.

 

REFERENCES

1. HENRY AK: Extensile Exposure. 2nd ed. Edinburgh: E&S Livingston; 1966.

2. HENRY AK: Exposure of the humerus and femoral shaft. Br J Surg.

   1924;12:84.

3. THOMPSON JE: Anatomical methods of approach in operating on the long bones of the extremities. Ann Surg. 1918;68:309.

4. HOLSTEIN A, LEWIS GM: Fractures of the humerus with radial nerve paralysis. J Bone Joint Surg [Am]. 1963;45-A:1382–1388.

5. WAGNER M, FRIGG R: Internal Fixators. New York: Thieme; 2006.

6. Apivatthakakul T, Arpornchayanon O, Bavornratanavech S:

   Minimally invasive plate osteosynthesis (MIPO) of the humeral shaft fracture. Is it possible? A cadaveric study and preliminary report.

   Injury. 2005;36(4):530–538.

7. JIANG R, LUO CF, ZENG BF, ET AL: Minimally invasive plating for complex humeral shaft fractures. Arch Orthop Trauma Surg. 2007;127(7):531–535.

8. GARDNER MJ, GRIFFITH MH, DINES JS, ET AL: The extended

   anterolateral acromial approach allows minimally invasive access to the proximal humerus. Clin Orthop Relat Res. 2005;434:123–129.

9. ZHIQUAN A, BINGFANG Z, YEMING W, ET AL: Minimally invasive plating osteosynthesis (MIPO) of middle and distal third humeral shaft fractures. J Orthop Trauma. 2007;21(9):628–633.

10. MCKEE MD, WILSON TL, WINSTON K, ET AL: Functional outcome following surgical treatment of intra-articular distal humeral fractures through a posterior approach. J Bone Joint Surg [Am]. 2000;82:1701.

11. BOYD HB, MCLEOD AC JR: Tennis elbow. J Bone Joint Surg [Am].

    1973;55:1183.

12. AHMAD Z, SIDDIQUI N, MALIK SS, ET AL: Lateral epicondylitis: a review of pathology and management. Bone Joint J. 2013;95-B(9):1158–1164.

13. KIM BS, PARK KH, SONG HS, ET AL: Ligamentous repair of acute lateral collateral ligament rupture of the elbow. J Shoulder Elbow Surg. 2013;22(11):1469–1473.

14. KWON BC, KWON YS, BAE KJ: The fascial elevation and tendon origin resection technique for the treatment of chronic recalcitrant medial epicondylitis. Am J Sports Med. 2014;42(7):1731–1737.

15. JOBE FW, STARK H, LOMBARDO SJ: Reconstruction of the ulnar collateral ligament in athletes. J Bone Joint Surg Am. 1986;68(8):1158–1163.

16. CONWAY JE, JOBE FW, GLOUSMAN RE, ET AL: Medial instability of the elbow in throwing athletes. Treatment by repair or reconstruction of the ulnar collateral ligament. J Bone Joint Surg Am. 1992;74(1):67–83.

17. SHAO YC, HARWOOD P, GROTZ MR, ET AL: Radial nerve palsy associated with fractures of the shaft of the humerus: a systematic review. J Bone Joint Surg Br. 2005;87(12):1647–1652.

18. LAST RJ: Anatomy Regional and Applied. 6th ed. Edinburgh: Churchill Livingstone; 1978.

19. STRUTHERS J: On a peculiarity of the humerus and humeral artery.

    Monthly J Medical Science. 1948;8:264.

20. SUTHERLAND S: Nerves and Nerve Injuries. Baltimore, MD: Williams & Wilkins; 1968.