Joaquin Sanchez-Sotelo
Adequate surgical exposure of the elbow joint is one of the most critical factors in achieving a successful outcome in both trauma and reconstruction. Elbow exposure is complicated by the need to identify and protect surrounding neurovascular structures, some of which are extremely close to the joint capsule. Various surgical exposures have been developed to mobilize the extensor mechanism or to allow access from the medial or lateral side of the joint while preserving the collateral ligaments; anterior exposures are seldom used for very specific indications (such as distal biceps tendon repair). The skin incision will be determined by the selected deep exposure as well as prior surgical skin incisions, but many elbow surgeons favor a universal posterior midline skin incision that allows almost circumferential exposure of the elbow joint. It is not the purpose of this chapter to discuss all the approaches to the elbow joint but rather to provide a summary of the approaches more commonly used by elbow surgeons at the present time.
Skin
Posterior Midline Skin Incision
Many elbow surgeons favor the use of a posterior midline skin incision for many elbow procedures. It has several advantages: (i) medial and/or lateral skin flaps can be elevated on demand to provide access to virtually any deep exposure, (ii) the risk of neuromas is minimized, as the number and diameter of nerve fibers crossing the posterior aspect of the elbow are low compared to the medial or lateral side, and (iii) should future surgery be needed, the same skin incision can be used for almost any procedure. Exposures that involve mobilization of the extensor mechanism are performed through this incision. It is also extremely useful for the treatment of elbow fracture-dislocations, which may require sequential access to both the medial and lateral side of the joint depending on the pathology found.
Wound-related complications are relatively uncommon provided full-thickness fasciocutaneous flaps are elevated; seromas or hematomas do happen occasionally, but they seldom compromise the outcome. The posterior midline skin incision is placed slightly off the tip of the olecranon either medially or laterally to facilitate healing. When the elbow needs to be splinted, the splint can be placed anteriorly to avoid direct pressure on the wound, and the elbow can be immobilized in extension and kept elevated to decrease swelling and surgical wound tension, as well as seroma or hematoma accumulation underneath the skin flaps.
Lateral and Medial Skin Incisions
Lateral or medial incisions are useful when no need for a more extensile approach is anticipated (Table 57-1); they can be complicated occasionally by neuromas (from transected branches of the lateral or medial antebrachial cutaneous nerves), especially on the medial side, but these more limited skin incisions are associated with a lower rate of wound complications than the posterior midline skin incision.
Lateral Approaches
The Köcher Approach
Classically, the lateral side of the elbow is exposed through the Köcher interval. This interval between the anconeus and the extensor carpi ulnaris is easily identified distally and developed proximally in line with the lateral epicondyle and humeral column. The underlying annular ligament, lateral collateral ligament complex, and elbow capsule are easily exposed. The Köcher approach can be used for radial head open reduction and internal fixation (ORIF) or replacement and is especially useful when the lateral collateral ligament complex is already injured, as in most fracture-dislocations; it represents the standard approach for reconstruction of the lateral collateral ligament (Fig. 57-1). Release of the lateral collateral complex off the lateral epicondyle through the Köcher interval allows great exposure of the subluxed or
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dislocated joint. However, increased understanding of the role of the lateral collateral ligament complex and concerns about its residual laxity after detachment have prompted the use of alternative ligament-sparing deep exposures.
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TABLE 57-1 Procedures Commonly Performed Through a Lateral or Medial Skin Incision |
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Common Extensor Group Split
One of the best exposures for internal fixation or replacement of the radial head is through a split in the extensor carpi radialis brevis(ECRB) in line with the Lister tubercle that is then continued proximally by detachment of the common extensor origin and anterior capsule off the lateral column. Incision of the annular ligament underneath the ECRB provides access to the radial head, and the supinator muscle can be elevated from proximal to distal if the radial neck needs to be exposed (Fig. 57-2). Care should be taken to protect the posterior interosseous nerve; placing the forearm in pronation displaces this nerve distally and allows safe exposure of at least 35 mm of proximal radius. A retractor placed around the neck may be used to lever the radial head and neck anteriorly for fixation or replacement.
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Figure 57-1 The Köcher approach uses the interval between anconeus and extensor carpi ulnaris. The interval is being used in this case to expose the lateral collateral ligament complex. |
Lateral Column
The proximal aspect of this approach, through detachment of the extensor muscle group origin off the lateral column and distal split of the extensor group in line with the Lister tubercle, allows excellent exposure to the anterior compartment; the posterior compartment can be easily exposed from the lateral side by elevation of the triceps and anconeus off the lateral column. These two combined form the basis of the so-called lateral column procedure (Fig. 57-3).
Medial Approaches
As noted above, the skin of the medial aspect of the elbow is richly innervated by multiple branches of the medial antebrachial cutaneous nerve. Incisions placed on this area have a high risk of neuroma formation, and some authors recommend identification and preservation of these branches when a medial skin incision is used. Alternatively, the medial aspect of the elbow may be exposed through a posterior midline skin incision by elevation of a medial skin flap.
Deep medial exposures vary depending on the procedure to be performed (Table 57-1). The medial side of the elbow joint is covered by the flexor-pronator group anteriorly and the triceps posteriorly. Medial collateral ligament (MCL) reconstruction used to be performed through detachment of the flexor-pronator group; currently, a muscle split is used for most MCL reconstructions, and detachment of the flexor-pronator group is reserved for submuscular transposition of the ulnar nerve, and may also be used for coronoid exposure and sometimes resection of heterotopic ossification.
Different approaches may be used for coronoid exposure. Coronoid plating and reconstruction require ample exposure. The author favors elevation of the flexor-pronator group off the subcutaneous border of the ulna from proximal to distal (Fig. 57-3). This exposure allows identification and preservation of the MCL which appears as a white collection of fibers as the fleshy flexor-pronator group is elevated; it does not require formal transposition of the ulnar nerve and limits the amount of muscle that needs to be detached from the distal humerus, providing good exposure to both the coronoid and the ulnar shaft.
The so-called medial column procedure provides access to both the anterior and the posterior compartments of the elbow and is used mainly for contracture release The principles of this approach are similar to those of the lateral column approach: preservation of the collateral ligament and ample access to the joint through a somewhat limited muscle dissection. The posterior compartment of the elbow is exposed by elevation of the triceps off the medial column. The anterior compartment is exposed by elevation of the pronator teres off the medial intermuscular septum and the anterior column; the exposure is extended distally
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through a split in the raphe between the flexor and pronator components of the flexor-pronator group.
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Figure 57-2 Radial head exposure through a muscle-splitting approach. A: The split in extensor carpi radialis brevis (ECRB) and proximal extension along the lateral column are marked in blue. B: The radial head is easily exposed through the split. C: Proximal extension of the approach along the column provides an excellent exposure for fixation or replacement. |
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Figure 57-3 Coronoid fractures may be exposed medially by elevation of the flexor-pronator group from distal to proximal. The medial collateral ligament, deep to the muscle group, is pointed out by the forceps. The medial side of the trochlea and the coronoid lie just anterior to the ligament. |
The Extensor Mechanism
Internal fixation of most distal humerus fractures and reconstruction of the elbow joint with either a joint prosthesis or interposition arthroplasty often require mobilization of the extensor mechanism. Table 57-2 summarizes surgical approaches to mobilize the triceps with some of their advantages and disadvantages.
Working on Both Sides of the Triceps
This approach was originally described by Alonso-Llames for the treatment of children's supracondylar fractures and their sequelae. Access to the distal humerus working on both sides of the triceps is ideal, as it preserves the extensor mechanism intact. However, it provides limited exposure to the articular surface. It is used mainly for internal fixation of selected simple distal humerus fractures, elbow arthroplasty in the presence of distal humeral bone loss, and supracondylar osteotomies.
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Figure 57-4 Some of the posterior exposures of the elbow joint. A: Paratricipital approach. B: Olecranon osteotomy. C: Bryan-Morrey triceps reflection. D: Triceps-reflecting anconeus pedicle (TRAP) approach. |
Triceps-Reflection
The triceps can be detached off the olecranon and reflected in continuity with the anconeus, forearm fascia, and ulnar periosteum from either lateral to medial or medial to lateral (Fig. 57-4). Reflection from medial to lateral, the Bryan-Morrey approach, is more commonly used, especially for elbow arthroplasty. The Köcher interval may be identified and developed laterally and the approach extended by reflecting the triceps and anconeus from lateral to medial, the so-called Mayo modified extensile Köcher approach. Both approaches require secure reattachment of the extensor mechanism with nonabsorbable transosseous sutures and avoidance of extension against resistance for about 6 weeks.
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TABLE 57-2 Surgical Exposures to Mobilize The Extensor Mechanism |
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Olecranon Osteotomy
This approach provides excellent exposure to the elbow joint, especially for the management of complex distal humerus fractures. There are some controversies regarding the ideal osteotomy configuration and fixation technique. Currently, most authors favor a chevron-shaped osteotomy initiated with a saw and completed with an osteotome to create additional microinterdigitation at the osteotomy site and avoid inadvertent damage to the articular cartilage. The osteotomy should be centered at the bare area of the olecranon (Fig. 57-4).
Plate fixation provides excellent stability, but it seems to increase the rate of wound complications. Tension band wiring using either a large-fragment partially threaded cancellous screw or two Kirschner wires is commonly used. When screw fixation is selected, drilling and tapping should be completed before performing the osteotomy, and screw length should be enough to provide cortical engagement while avoiding mediolateral translation of the osteotomized fragment with introduction of a long straight screw in the bowed ulnar canal. When Kirschner wires are used, wire placement through the anterior ulnar cortex may decrease the risk of postoperative migration. The main complications
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of olecranon osteotomy are nonunion and hardware-related complications.
Triceps Split
The triceps can be split in the midline to expose the distal part of the humerus. The split may be extended distally by elevation of medial and lateral subperiosteal flaps off the ulna. This approach is recommended by some mainly for elbow arthroplasty. It maintains the extensor mechanism centralized, but the attachment of the medial half of the triceps is often thin, which may compromise the quality of the repair.
The Triceps-Reflecting Anconeus Pedicle Approach
The triceps-reflecting anconeus pedicle (TRAP) approach was developed for internal fixation of complex distal humerus fractures to avoid the disadvantages of olecranon osteotomy while providing improved exposure over triceps-reflection approaches. It basically involves complete detachment of the triceps and anconeus off the proximal ulna by combining the Bryan-Morrey and the extensile Köcher approaches (Fig. 57-4). The joint can be exposed by elbow hyperextension, and the ulna is kept intact to be used as a template for reconstruction of the distal humerus articular surface or in case conversion to elbow replacement becomes necessary. It may lead to weakness in terminal extension.
Anterior Approaches
Anterior approaches to the elbow have very specific indications. Some authors recommend an anterior approach for contracture release, but access to the posterior compartment is required for most contracted elbows, which makes this approach somewhat unappealing. Currently, the anterior aspect of the elbow is exposed most commonly for repair of distal biceps tendon injuries. Either a small anterior incision used to retrieve the tendon is then combined with a second incision in the proximal aspect of the dorsal forearm, or a single larger anterior approach is used for both tendon retrieval and reattachment. Care should be taken to protect the median and radial nerves as well as the brachial artery. Care should also be taken to avoid crossing the elbow flexion crease at a right angle to decrease the chance of skin contracture limiting elbow extension. Moisture accumulated in the elbow flexion crease when the joint is immobilized in some flexion may increase the risk of wound-related complications after any anterior approach.
Suggested Readings
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Bryan RS, Morrey BF. Extensive posterior exposure of the elbow. A triceps-sparing approach. Clin Orthop. 1982;166:188–192.
Diliberti T, Botte MJ, Abrams RA. Anatomical considerations regarding the posterior interosseous nerve during posterolateral approaches to the proximal part of the radius. J Bone Joint Surg. 2000;82A:809–813.
Dowdy PA, Bain GI, King GJ, et al. The midline posterior elbow incision. An anatomical appraisal. J Bone Joint Surg. 1995;77B:696–699.
Frankle MAMD. Triceps split technique for total elbow arthroplasty. Techniques Shoulder Elbow Surg. 2002;3(1):23–27.
Husband JB, Hastings H II. The lateral approach for operative release of post-traumatic contracture of the elbow. J Bone Joint Surg.1990;72A:1353–1358.
Mansat P, Morrey BF. The column procedure: a limited lateral approach for extrinsic contracture of the elbow. J Bone Joint Surg. 1998;80A:1603–1615.
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Wada T, Ishii S, Usui M, et al. The medial approach for operative release of post-traumatic contracture of the elbow. J Bone Joint Surg. 2000;82B:68–73.