Master Tech Ortho Surgery Elbow CH1

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1  Exposures of the Upper Extremity: Humerus, Elbow, Forearm

THE EXTENSILE POSTERIOR MEDIAL EXPOSURE OF THE HUMERUS (MAYO EXPOSURE) Comment We have found this approach extremely valuable for exposing the posterior aspect of the humerus since it allows extension distally by employing the triceps reflexion exposure from the olecranon. This is a unique (Mayo) feature to the manner of exposing and protecting the radial nerve. Indications Fractures of the posterior aspect of the humerus, extensile exposure for revision of total elbow, humeral, and ulnar components. Position The patient is supine, and the arm is brought across the chest. The surgical table is tilted at 10 degrees opposite to the side of the surgeon. Skin Incision Proximally from the posterior medial aspect of the triceps in line with the long head and distally between the medial epicondyle and tip of the olecranon (Fig. 1A-7). Note : This excision can be extended distally over the subcutaneous border of the ulna if required.

FIGURE 1A-7

Technique ●● The skin and subcutaneous tissue are entered, and the ulnar nerve is identified, and flaps are raised medially and laterally (Fig. 1A-8A and B). ●● The ulnar nerve is identified lying on the posterior surface of the intermuscular septum. The fascia protecting the nerve is split proximally, including the ligament of Struthers. The nerve is identified distally to the level of the cubital tunnel, but the cubital tunnel retinaculum is not released. ●● With sharp dissection, the triceps is freed from the distal aspect of the humerus (Fig. 1A-9B). The medial head of the triceps as well as the medial aspect of the long head of the triceps are retracted laterally. ●● The muscle is then elevated from the entire posterior medial aspect of the humerus with a perios- teal elevator (Fig. 1A-10). Note : The critical departure of this exposure is that it is extended, releasing the intramuscular sep- tum, elevating the radial nerve subperiosteally, and retracting it laterally. ●● At this point, the triceps position is restored. The radial nerve is palpated as it penetrates the inter- muscular septum laterally (Fig. 1A-11). ●● Once the location has been identified, the triceps muscle is reflected from medial to lateral, and the radial nerve is identified at the site of its penetration of the intermuscular septum laterally (Fig. 1A-12). The intermuscular septum is then elevated from the lateral aspect of the humerus. In so doing, this affords greater access to the proximal aspect of the humerus (Fig. 1A-13A and B).