Comment on the anterior approach for coronoid process fracture

Abstract

We are very interested in the article by Han et al. [1] entitled ‘‘anterior approach for fixation of isolated type III coronoid process fracture’’. It’s well known that the coronoid process is the anterior portion of the proximal articular surface of the ulna and the important bone structure providing ulnohumeral joint anterior stability. There are two osseous eminences in the coronoid process, the tip and the sublime tubercle. Some important soft tissue structures insert on the coronoid process: the anterior articular capsule, the tendon of the brachialis muscle, and the anterior band of the medial collateral ligament (AMCL). The structures maintain the anterior stability of elbow together. The study of coronoid process fracture has been the central issue of elbow trauma and instability in recently years. The fractures of coronoid process are commonly associated with complex elbow fracture-dislocation, and isolated coronoid process fractures are uncommon. There is some controversy about fixation means of the coronoid process fragment. As described in the article that many published papers with treatment of coronoid fractures, but little has been published about the surgical approach related to operative fixation. The most common approach for fixation of coronoid process fractures has been described from medial and posterior. The anterior approach is seldom used, and rare relevant literatures about anterior approach for coronoid process fractures were reported. Because the brachial artery and its branches, median nerve, which lie in the anterior of the elbow. There is great risk of iatrogenic injury to the neurovascular structures. The medial approach is the most commonly used in our institution. But we found that it is usually hard to exposure the fragments of the coronoid process from the medial incision clearly, because of the very thick flexor-pronator mass. We had performed some dissection research about the anterior approach to expose the coronoid process. In the course of our study, we found that there are some branches from the proximal radial artery and ulna artery, which constitute the vascular tree in the superficial structure of the brachialis insertion. Especially, the radial recurrent artery traverses the brachialis muscle surface. The distance of the brachial artery retracted medially is restricted by the anatomical characteristics. There are some difficulties to reduce and fix the coronoid fragment with a buttress plate in this area, but the cannulated screw is convenient to be used. We admired the authors’ skilled technique and courage. So we also want to consult some detail technique about the exposure of the coronoid process during the operation. How to optimally handle the artery branches to harvest more operating space? Whether the radial recurrent artery must be cut? The anterior approach can not be used to repair the associated ligament injury (lateral collateral ligament or medial collateral ligament). In the article, the author described that the cases were all isolated coronoid process fracture without associated ligament injury resulting in joint instability. The study was retrospective, so the incision position must be determined preoperatively. In other words, the patients with coronoid process fracture and elbow dislocation, without ligament injury, should be made a definite diagnosis before operation. How to ensure that the patients were not associated ligament injury resulting in instability of ulnohumeral joint? What accessory examination should be performed? We think that it is not accurate to diagnose the ligament without injury only through X. Zhu X. Wang (&) Z. Ma Department Orthopedic Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China e-mail: wangxin1681@126.com