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Fractures of the Coracoid Process: Evaluation, Management, and Outcomes 2020;00:1-10 Copyright © the American Academy of Orthopaedic Surgeons

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Fractures of the Coracoid Process: Evaluation, Management, and Outcomes 2020;00:1-10 Copyright © the American Academy of Orthopaedic Surgeons Review Article Fractures of the Coracoid Process: Evaluation, Management, and Outcomes 05/09/2020 on BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD3FlQBFFqx6X+UIgM2hyMEHeYUpK737LP7vR/A3eYg0e8= by https://journals.lww.com/jaaos from Downloaded Abstract Joseph W. Galvin, DO Fractures of the coracoid process are relatively rare, and current Downloaded Jeansol Kang, MD management guidelines remain unclear. Most coracoid fractures occur from in conjunction with other shoulder injuries, including dislocations and Richard Ma, MD https://journals.lww.com/jaaos fractures. Identifying coracoid fractures can be difficult because most Xinning Li, MD fractures are nondisplaced and can be missed on radiographs or may be masked by other injuries. Management is largely guided by fracture location and displacement. Conservative treatment is preferred for by fractures that are minimally displaced, whereas indications for surgical BhDMf5ePHKav1zEoum1tQfN4a+kJLhEZgbsIHo4XMi0hCywCX1AWnYQp/IlQrHD3FlQBFFqx6X+UIgM2hyMEHeYUpK737LP7vR/A3eYg0e8= fixation include fractures that are displaced (.1 cm), have progressed to a painful nonunion, or are associated with the disruption of the superior shoulder suspensory complex. Although conservative treatment has been historically favored, satisfactory outcomes have been reported for both surgical and nonsurgical treatment. We provide a comprehensive review of diagnosis and management strategies for coracoid fractures. oracoid fractures are relatively primarily based on level IV and V evi- Crare injuries that typically occur dence. The surgical indications for because of high-energy trauma, such coracoid fractures are evolving as a as a motor vehicle accident. However, better understanding of associated in- From the Department of Orthopaedic Surgery, Madigan Army Medical blunt trauma related to sporting juries and surgical instrumentation or Center (Dr. Galvin), Tacoma, WA, the activities have also been described as a techniques improve. Department of Orthopaedic Surgery, mechanism of injury along with The purpose of this study is to Boston University School of Medicine repetitive stress-related injuries. Most (1) review the incidence, rele- (Dr. Kang and Dr. Li), Boston, MA, and the Department of Orthopaedic coracoid fractures do not occur in iso- vant anatomy, and mechanism Surgery, University of Missouri School lation because of the high-energy of injury related to coracoid on 05/09/2020 of Medicine (Dr. Ma), Columbia, MO. mechanism of injury and is typically fractures, Dr. Li or an immediate family member associated with additional injuries to (2) describe relevant workup for holds equity in JoMI. None of the the affected shoulder, particularly to diagnosis of coracoid fractures following authors or any immediate the other structures of the superior with a focus on injury classifica- family member has received anything shoulder suspensory complex (SSSC). tion and the types of associated of value from or has stock or stock options held in a commercial company Careful clinical evaluation including injuries found in conjunction or institution related directly or imaging of the affected shoulder is with coracoid fractures, indirectly to the subject of this article: essential because the presence of con- (3) discuss relative surgical in- Dr. Galvin, Dr. Kang, and Dr. Ma. comitant injuries may affect treatment dications for coracoid fractures J Am Acad Orthop Surg 2020;00:1-10 decision-making. Owing to the relative including a succinct review of the DOI: 10.5435/JAAOS-D-19-00148 rarity of these injuries, the literature outcomes after surgical manage- surrounding the management of cora- ment, and Copyright 2020 by the American Academy of Orthopaedic Surgeons. coid fractures is limited. The available (4) discuss the areas of future evidence to guide treatment decisions is work for coracoid fractures. Month 2020, Vol 00, No 00 1 Copyright © the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited. Fractures of the Coracoid Process the attachment of the conjoint tendon joint injuries should more commonly Regional Anatomy of the at the coracoid process, resulting in involve a tear of the CC ligaments Coracoid avulsion of the coracoid tip.5-10 Fatigue rather than a coracoid fracture.23 To fractures of the coracoid process have explain the combined coracoid frac- Most coracoid fractures are associated also been described in trap shoot- ture and AC separation in adults, Li with additional injuries to the affected ers,11,12 cricket players,6,13,14 and ten- et al24 proposed a two-step mech- shoulder, particularly to the SSSC. nis players,7 where it is likely that anism in which the sudden contrac- Therefore, surgeons should understand repetitive direct microtrauma ulti- tion of the conjoint tendon and the complex anatomy of the coracoid mately leads to bony failure of the pectoralis minor muscle produces a process and have knowledge of the coracoid. In addition, isolated frac- fracture of the coracoid and the com- attachment sites of the conjoint tendon, tures can occur secondary to iatrogenic ponent residual force along the CC coracoclavicular (CC) (trapezoid and surgical etiologies such as trans- ligaments determines whether the CC conoid) ligaments, coracoacromial coracoid drilling for suture button ligament is disrupted. (anterior and posterior bundles) liga- fixation of unstable acromioclavicular ment (CAL), coracohumeral ligament, (AC) joint separations and after and pectoralis minor. The minimum reverse shoulder arthroplasty.15-17 Physical Examination distance between the tip of the coracoid Most coracoid fractures occur in Findings and the most anterior CC ligament conjunction with other ipsilateral (trapezoid) is 25.1 mm, and sex differ- Identifying coracoid fractures via shoulder injuries. This pattern is typi- ences are present with a mean of physical presentation can be difficult as cally because of high-energy trauma, 28.1 mm and 22.0 mm in men and physical examination findings may be most often a direct blow from a motor women, respectively.1 nonspecific and are often masked by vehicle accident or fall.18-21 Associated other concomitant shoulder injuries. injuries include glenohumeral joint Isolated fractures typically present Epidemiology and injuries, AC joint injuries, rotator cuff with pain and tenderness to palpation tears, and fractures of the acro- Mechanism of Coracoid over the coracoid. Patients may also mion, scapula, distal clavicle, and Fractures exhibit limited, painful active shoulder humerus.18,19 The most common abduction, flexion, and/or external McGinnis and Denton2 described the associated injury is AC joint separa- rotation, but the neurovascular exam- prevalence of coracoid fractures tion.9,18-20 In the largest series of ination is usually normal.6,13,25 between3%to13%ofallscapula coracoid fractures involving nonsport- Examination findings in nonisolated fractures after a review of the litera- related trauma, Ogawa et al18 found cases vary depending on the associated ture in 1989. More recent data from that 58% (39/67) of patients with injuries. The most common combi- two systematic reviews of scapula coracoid fractures had associated AC nation of coracoid fracture with AC fractures in 2006 and 2008 reported joint injuries. Similarly, in a review of joint injury may present with addi- the prevalence of apophyseal (acro- sport-related coracoid fractures, Kna- tional findings of pain and tenderness mion, coracoid, and scapular spine) pik et al20 reported concurrent AC joint to palpation over the AC joint, visible fractures at 6% and 8.2%, respec- injury in 60% of patients. deformity, and painful cross-body tively.3,4 Isolated coracoid fractures The mechanism resulting in this adduction.21,24,26-28 Owing to the are rare, with 43 case reports in the combination of injury proposed by presence and severity of associated English literature and few retrospec- Wilson et al involves a direct force to injuries, coracoid fractures may be tive case series. the AC joint, causing caudad dis- overlooked—therefore, the physical Coracoid fractures are generally placement of the acromion and scap- examination should be performed due to high-energy direct impact ula, whereas the CC ligaments pull the with a focus on the reported mech- injuries or eccentric pull through soft- coracoid cephalad.10 This may result anism of injury. tissue attachments (ie, conjoint ten- in a coracoid fracture in skeletally don or CC ligaments) resulting in immature patients in whom the CC failure of the bone. Isolated fractures, ligaments are relatively stronger than Imaging as described in case reports, are often the unfused epiphyseal plate of the because of acute trauma, wherein a coracoid.9,22 However, this may not True anterior-posterior, scapular-Y, sudden and violent contraction of the explain all coracoid fractures in and axillary lateral views will help coracobrachialis and the short head adults, where the relative strength of visualize the fracture. An MRI or CT of the biceps brachii muscles during the coracoid and clavicle in relation to scan with three-dimensional recon- resisted elbow flexion places stress at the CC ligaments suggest that AC struction assists in understanding the 2 Journal of the American Academy of Orthopaedic Surgeons Copyright © the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited. Joseph W. Galvin, DO, et al Figure 1 Photographs showing relevant anatomy for classification of coracoid
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