Surgical Exposures of the Elbow

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CHAPTER 7 Surgical Exposures of the Elbow

GENERAL PRINCIPLES

Rigorous adherence to the principles of good surgical technique is of no greater importance in any anatomic part than at the elbow.6,8,35 The most appropriate surgical approach depends on the specific goal of the surgical intervention and on the lesion. As for any orthopedic procedure, the choice of the surgical approach should be based on the following criteria (Box 7-1):

A thorough understanding of the anatomy of the elbow region and the relationship of the nerves and vessels is particularly important to selecting the exposure that best satisfies these requirements (Fig. 7-1).

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FIGURE 7-1 Cross-sectional anatomy shows the important neurovascular and muscular relationships that must be understood to achieve a complication-free exposure of the elbow.

(Modified from Eycleshymer, A. C., and Schoemaker, D. M.: A Cross Section Anatomy. New York, D. Appleton and Co., 1930. In Darrach, W.: Surgical approaches for surgery of the extremities. Am. J. Surg. 67:93, 1945.)

LATERAL APPROACHES

A lateral exposure, probably the most commonly used approach to the elbow joint, offers many variations. It is used for radial head excision, removal of loose bodies, and repair of lateral ligaments, to fix condylar and Monteggia fractures, to release the joint capsule, and to remove osteophytes. Access to the radiohumeral articulation has been described by several authors.7,18,21,24,36 The techniques differ according to the muscle interval entered and the means of reflecting the muscle mass from the proximal ulna. With any of the lateral exposures to the joint or to the proximal radius, the surgeon must be constantly aware of the possibility of injury to the posterior interosseous or recurrent branch of the radial nerve.

Kaplan has described an approach through the interval between the extensor digitorum communis and the extensor carpi radialis longus and brevis muscles. Because of the proximity of the radial nerve, pronation of the forearm during exposure has been recommended to assist in carrying the radial nerve out of the surgical field. The effect of this maneuver has been quantified by Strachan and Ellis, who found that approximately 1 cm of mediolateral radial nerve translation can occur with forearm pronation (Fig. 7-2).42

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FIGURE 7-2 Approximately 1 cm of medial to lateral translation of the posterior interosseous nerve occurs as the forearm is rotated from supination to pronation.

(Redrawn from Strachan, J. H., and Ellis, B. W.: Vulnerability of the posterior interosseous nerve during radial head resection. J. Bone Joint Surg. 53B:320, 1971.)

Even with this maneuver, however, the radial nerve is precariously close to the surgical field, so this approach is used less often than that described by Kocher. Knowledge of Kaplan’s interval24 is useful to expose the posterior interosseous nerve when decompression is performed in conjunction with tennis elbow release (see Chapter 44).41

THE KOCHER APPROACH AND ITS VARIATIONS

Some variation of the Kocher exposure is the most frequently used approach to the lateral aspect of the joint. This has the advantage of being extensile, affording a full complement of surgical options as the exposure is extended. This approach enters the joint through the interval of the anconeus and extensor carpi ulnaris, thus providing protection to the deep radial nerve. The interval is also anterior to the lateral ulnar collateral ligament, which reduces the likelihood of severing it at arthrotomy. In addition to providing a limited exposure for radial head excision and loose body removal, the particular value of this technique is that it may be converted to an extensile posterolateral approach to the entire distal humerus. If an extensile exposure is anticipated, a posterior incision is made. The same deep exposure can be accomplished by extending the posterior lateral skin incision and elevating the lateral skin cutaneous flap.

Limited Distal Lateral Approach: Kocher “J”

Interval

The interval between the anconeus and extensor carpi ulnaris is identified and entered (Fig. 7-3B). For excision of the radial head, the extensor carpi ulnaris and a small portion of the supinator muscle are dissected free of the capsule and retracted anteriorly (see Fig. 7-3C). The annular ligament is then identified and entered. Care should be taken to enter the annular ligament approximately 1 cm above the crista supinatoris to avoid injury to the lateral ulnar collateral ligament (see Fig. 7-3D).

Expanding the Distal Lateral Exposure

Interval

After the interval is entered, the anconeus is more completely reflected from its ulnar insertion (Fig. 7-4A). The lateral collateral ligament complex is identified by first elevating the extensor carpi ulnaris from the annular ligament just distal to the lateral epicondyle (see Fig. 7-4B). The fleshy attachment of the extensor carpi radialis longus is identified just above the common extensor tendon. This origin is freed from the supracondylar ridge. The dissection then elevates the common extensor tendon and the posterior edge of the extensor carpi radialis brevis from the lateral ligament complex (see Fig. 7-4D). This is done very carefully to identify and leave intact the lateral collateral ligament complex, and thus, reconstruction of the lateral ulnar collateral ligament can take place (see Chapter 48).

The Limited Proximal Lateral Exposure (Column Approach)

Skin Incision and Technique

This limited exposure of the anterior (and posterior) capsule has been described by Mansat and Morrey.28 The skin incision is over the lateral column, extending distally over the lateral epicondyle to the radial head (Fig. 7-5A). The extensor carpi radialis longus and distal fibers of the brachial radialis are elevated from the lateral column and epicondyle (see Fig. 7-5B). The brachialis muscle is separated from the anterior capsule, which can be safely performed if the joint has been entered at the radiocapitellar articulation. Since the arthrotomy provides accurate spatial orientation across the joint, damage to neurovascular structures is avoided. The procedure then continues as described in Chapter 44.

POSTEROLATERAL EXPOSURES

THE BOYD POSTEROLATERAL EXPOSURE7

Exposure of the lateral ulnohumeral and radiohumeral joint is accomplished with several variations of a posterolateral approach described by Boyd. Depending on the need to expose the proximal ulna or the distal humerus, these approaches can be extended and thus provide significant versatility.40

Skin Incision

Begin the incision just posterior to the lateral epicondyle and lateral to the triceps tendon, and continue the incision distally to the lateral tip of the olecranon and then down the subcutaneous border of the ulna to the junction of its proximal and middle thirds or as necessary in order to expose the fracture (Fig. 7-6A).

Technique

The anconeus and extensor carpi ulnaris are stripped subperiosteally from the ulna, beginning on the lateral subcutaneous crest of the bone and reflecting the muscles volarward. The supinator is released subperiosteally from its ulnar insertion, and the entire muscle mass is reflected anteriorly (see Fig. 7-6B). Be careful not to detach the ulnar attachment of the lateral ulnar collateral ligament. Thus, the lateral surface of the ulna and the proximal portion of the radius are adequately exposed (see Fig. 7-6C). The substance of the reflected supinator protects the deep branch of the radial nerve (see Fig. 7-6D). If greater exposure of the radius is desired, the recurrent interosseous artery (not the dorsal interosseous artery) is divided in the proximal portion of the wound, and the muscle mass is further reflected volarward to expose the interosseous membrane. The deep branch of the radial nerve remains protected.

EXTENSILE POSTEROLATERAL EXPOSURE (KOCHER)

This is an extension of the limited exposures described above involving the release of collateral ligament and capsule.24

Skin Incision and Technique

The triceps may be elevated from the posterior aspect of humerus by extending the skin incision proximally up the lateral column (Fig. 7-7A). This may proceed 6 to 7 cm proximal to the lateral epicondyle without fear of violence to the radial nerve.

Proceed as shown in Figure 7-7B by completely elevating the anconeus from the ulna. The triceps is easily elevated from the posterior humerus in the normal situation, and even in post-traumatic contractures, the triceps can be elevated with a periosteal elevator without much additional difficulty (see Fig. 7-7C). The lateral collateral ligament is released from the humeral origin as a separate structure or if prior surgery has caused scarring, with the common extensor tendon complex. The anterior capsule is then incised. A varus stress is applied to the elbow, which opens like a book hinging on the medial ulnar collateral ligament and common flexor muscles (see Fig. 7-7D). The triceps remains attached to the ulna.

MAYO MODIFIED KOCHER EXTENSILE POSTEROLATERAL EXPOSURE

Technique

If more extensile exposure is required than has been obtained with the previous steps (see Figs. 7-5 and 7-6), a medial skin flap is elevated and the ulnar nerve identified. It is protected or translocated according to the merits of the case and after the release has proceeded according to the steps shown in Figure 7-6. The triceps and anconeus muscle sleeve is reflected from the tip of the olecranon by releasing Sharpey’s fibers (see Fig. 7-8A). The entire extensor mechanism including anconeus is thus reflected from lateral to medial (see Fig. 7-8B). After the triceps has been reflected and the posterior capsule released, the lateral collateral ligament may be detached from the humerus depending on the goal of the specific procedure and the additional exposure required. By flexing the elbow and removing the tip of the olecranon, the articular surface and the entire posterior humerus can be exposed.

POSTERIOR EXPOSURES

Extensile posterior exposure implies effective management of the triceps mechanism.5,37 In recent years, there has been a marked increased interest in revisiting and modifying previously described posterior surgical approaches.

A posterior exposure of the elbow joint may be used for virtually any surgical indication. In fact, a posterior skin incision is now considered to be the universal approach to any deep structure of the elbow. Because the dissection may be readily extended and tissues mobilized medially and laterally, distal humeral and proximal ulnar fractures, joint reconstruction, tumors, infections, and synovial processes are amenable to treatment through a posterior exposure.

Several skin incisions and techniques have been described. Although MacAusland27 used a transverse incision, most posterior skin incisions are longitudinal. The S incision of Ollier today is not as often used as the straighter incision recommended by Langenbeck.25 Probably the most important aspect of any incision is that it should not cross the tip of the olecranon. Smith also attributed better healing to a medial incision as compared with a lateral one.38

Releasing the triceps transverse section of the triceps mechanism at its musculotendinous junction has been described but does not afford adequate repair for optimal rehabilitation.46 Releasing the triceps at its attachment to the olecranon26 is not advisable, owing to the difficulty of adequate repair and possible disruption during rehabilitation.9 Today we categorize triceps management into four categories: (1) triceps splitting, (2) triceps reflecting, (3) triceps preserving, and (4) olecranon osteotomy (Fig. 7-9). A midline splitting incision was described as early as 1918 by James Thompson to expose the distal humerus for fractures, but it did not include release from the ulna to provide exposure of the joint itself.44

Splitting the triceps in line with the muscle fibers and at its insertion to expose the humerus and the elbow joint was described by Langenback25 and Campbell.10 This approach has had considerable resurgence of interest in recent years. When contracture is present, Campbell first separated the tendon from the muscle as an inverted V and then released the muscle fibers longitudinally. This technique, recommended later by Van Gorder46 for distal humerus fractures, allows lengthening of the musculotendinous unit, which may be necessary to fully mobilize the ankylosed joint. This triceps torque exposure has also faced a renewed interest and popularity in recent years.