Complete exposure of the radius

Abstract

THE entire length of the radius is most easily exposed through an anterolateral incision. ANATOMY.Three long muscles flank the bone upon its outer or lateral border---the brachioradialis, miscalled the supinator longus, and the long and short radial extensors of the wrist (Fig. 324). They can be retracted outwards when they have been relaxed by bending thc elbow. These three muscles have origins FIG. 328. -Anatotoical relationships nt the upper part of the radius. The white crescnnt hetaeen the two black insertions represents the bicipital bursa and shows how it lies in a bay formcd by thn supinntor edge. The surgeon is guided l o the h r s a by thc outer face of the biceps tondon. face of the biceps tendon.which are proximal to the elbow-joint, and in order to mobilize them fully, the incision must extcnd proximal to the elbow. Further, this lateral group of three is strapped t o the lower fourth of the radial shaft by two small muscleswhich form an oblique proniinencc when the hand is prone. When the long muscles are raised from the bone these two short muscles are raised with them. The pronator teres, inserted at the middle of the radial shaft upon its outer face, will then be exposed, and full pronation of the hand will reveal an expanse of bone in the lower half of the shaft.The supinator muscle grasps the upper third of the shaft, and the posterior interosseous nerae (deep branch of the radial-l3.X.A.) penetrates the ariterolateral face of the supinator, and lies between two layers of the muscle : the deep layer separates the nerve from the bone. The supinator attachmcnt to thc radius skirts the edge of thc bicipital tuberosity, which is covered in front by a bursa (Fig. 322).Tht Deep Guide.-The edge of the supinator is obscured by the loose connective tissue that surrounds the recurrent radial vessels, but it can be reached with precision by following the outer The outer face of the tendon leads the surgeon to the bursa : -the knife cuts through this to the tuberosity and a t once affords t,he rugirie a point of direct contact with the bone (Fig. 325). It is * Shown at the Section of Surgery, Royal Academy of Medicine in Ireland. April 3, 1915.

Anatomic considerations regarding the posterior interosseous nerve at the elbow

“…7,8,15 Given the measurements in this and other studies, it is more appropriately termed contact with the proximal diaphysis, not the neck of the radius. 1,4,5,13,14,16,17,23 The contact is along the entire portion of the PIN as it progresses from a proximal/anterior to distal/lateral structure in the forearm.…”

“…Contrasting previous assertions, pronation did not yield a reliable additional increase in this safe zone. 2,3,7,10,11,13,14,21 Any protection of the PIN beyond the 1.1 cm of distal displacement found by placing the forearm in pronation would come from medial displacement of the nerve or interposed structures. The absence of muscle fibers found deep to the nerve suggests that surgeons should not rely on an interposed deep head of the supinator muscle for protection.…”

“…8,10,11 Next, a modified Henry approach between the brachioradialis and the flexor carpi radialis allowed exposure of the PIN in the volar forearm. 7,8 Through the anterior approach, dissection was carried out laterally; a few fibers of the musculature were split to identify the nerve within the supinator. Care was taken to ensure that the PIN was left in situ.…”

“…) The location and course of the posterior interosseous nerve (PIN) at the elbow and proximal forearm have been depicted and described in many surgical anatomy texts. [7][8][9][10][11]23 The relationship of the PIN to the proximal radius during the lateral approach to the elbow, as described by Kocher,11,12 is of particular interest, as this is a common surgical exposure. 8,9 A variety of procedures, including open reduction-internal fixation of a radial head or neck fracture, synovectomy or radial head excision, lateral collateral ligament reconstruction, and unconstrained total elbow arthroplasty, may place the nerve at risk.…”

Comparison Between Incidence of Posterior Interosseous Nerve Injury Following Volar Approach and Dorsal Approach in Fixing Fractures of Proximal Half of Radial Shaft

“…They reported one case of infection and two cases of damage to the sensory branch of radial nerve which recovered. In their study, range of approach and good coverage on the plate were reported as benefits of the VA. 13 The anterior or volar approach (VA) described by Henry in 1927, 14 is preferred for biceps repair and boast a distal extensile approach with adequate soft tissue coverage. The PIN may be at risk during this approach and pressure on the nerve during retraction may lead to neurapraxia.…”