MUSCULOSKELETAL IMAGING 2084 Coracoid Process: The Lighthouse of the Shoulder 1 The coracoid process is a hook-shaped bone structure project- ing anterolaterally from the superior aspect of the scapular neck. Surgeons often refer to the coracoid process as the “lighthouse of the shoulder” given its proximity to major neurovascular structures such as the brachial plexus and the axillary artery and vein, its role in guiding surgical approaches, and its utility as a landmark for oth- er important structures in the shoulder. The coracoid also serves as a critical anchor for many tendinous and ligamentous attachments. These include the tendons of the pectoralis minor, coracobrachialis, and short head of the biceps brachii muscles, and the coracocla- vicular, coracohumeral, coracoacromial, and transverse scapular ligaments. Consequently, the coracoid and its associated structures are linked to numerous shoulder pathologic conditions. This article will detail the anatomy of the coracoid and its associated structures and review the clinical and radiologic findings of corresponding pathologic conditions in this region with original illustrations and multimodality imaging examples. Highlighted in this article are the coracoclavicular joint, the classification and management of coracoid fractures, subcoracoid impingement, the coracoacromial arch and subacromial impingement, the coracohumeral ligament and the biceps pulley, the coracoclavicular ligament and its surgi- cal reconstruction, adhesive capsulitis, the suprascapular notch and suprascapular notch impingement, subcoracoid bursitis, coracoid transfer procedures, and coracoid tumors. A brief summary of the pathophysiology, potential causes, and management options for each of the pathologic entities will also be discussed. © RSNA, 2016฀•฀radiographics.rsna.org Hussan Mohammed, MD Matthew R. Skalski, DC Dakshesh B. Patel, MD Anderanik Tomasian, MD Aaron J. Schein, MD Eric A. White, MD George F. Rick Hatch III, MD George R. Matcuk Jr, MD Abbreviations: AP = anteroposterior, FS = fat saturated, PD = proton density weighted, STIR = short inversion time inversion-recovery RadioGraphics 2016; 36:2084–2101 Published online 10.1148/rg.2016160039 Content Codes: 1 From the Departments of Radiology (H.M., D.B.P., A.T., A.J.S., E.A.W., G.R.M.) and Or- thopaedic Surgery (G.F.R.H.), Keck School of Medicine, University of Southern California, 1500 San Pablo St, 2nd Floor Imaging, Los An- geles, CA 90033-5313; and Department of Radi- ology, Southern California University of Health Sciences, Whittier, Calif (M.R.S.). Recipient of a Certificate of Merit award for an education exhibit at the 2015 RSNA Annual Meeting. Re- ceived March 5, 2016; revision requested April 19 and received May 10; accepted May 24. For this journal-based SA-CME activity, the authors, editor, and reviewers have disclosed no relevant relationships. Address correspondence to G.R.M. (e-mail: matcuk@usc.edu). © RSNA, 2016 After completing this journal-based SA-CME activity, participants will be able to: ■ Identify the anatomy related to the coracoid process, including its tendon and ligament attachments, the coracoac- romial arch, the biceps pulley, the su- prascapular notch, and the subcoracoid bursa. ■ Describe various pathologic conditions of the coracoid and its associated struc- tures in terms of clinical presentation, imaging findings, and management. ■ Discuss surgical considerations involv- ing the coracoid process. See www.rsna.org/education/search/RG. SA-CME LEARNING OBJECTIVES Introduction One of the most fundamental principles of shoulder surgery is to embark on an approach that is lateral to the coracoid process, to avoid the vital neurovascular structures that run medially, such as the brachial plexus and branches of the axillary artery and vein. There- fore, the coracoid has been dubbed the “lighthouse of the shoulder” by some orthopedists (1). In addition to serving as a palpable landmark in guiding surgical approaches, the coracoid serves as a critical attachment anchor for several tendons and ligaments. These include the tendons of the pec- toralis minor, coracobrachialis, and short head of the biceps brachii muscles, and the coracoclavicular, coracohumeral, coracoacromial, and suprascapular ligaments (2). Thus, it comes as no surprise that among the litany of causes of anterior shoulder pain, the coracoid or one of its related structures is often implicated. Given the numerous key structures involving this relatively small region and the clinical reliance on imaging to confirm a diagnosis, detailed knowledge of coracoid process anatomy and its related structures is crucial in mus- culoskeletal radiologic practice yet challenging to attain. This copy is for personal use only. To order printed copies, contact reprints@rsna.org