E2178. The Five Most Important MRI Findings to Assist Orthopedists in Surgical Planning for Rotator Cuff Tears
  1. Caoimhe Byrne; University of British Columbia
  2. Jennifer Hennebry; University of British Columbia
  3. Adnan Sheikh; University of British Columbia
  4. Bruce Forster; University of British Columbia
Rotator cuff tears (RCTs) are a common and lifestyle limiting pathology. They are the most common atraumatic shoulder pathology in people over the age of 50, affecting 20% of the adult population. In patients who fail conservative treatment, surgical repair is considered with a goal of restoring tendons to their anatomic insertion site. Rotator cuff repair (RCR) has a mean failure rate of 25%. Depending on patient and anatomic factors, complete tendon-to-bone repair is not always possible or suitable and other surgical approaches can be considered. These include superior capsular repair using auto- or allograft and reverse total shoulder arthroplasty. The aim of this educational exhibit is to describe with imaging examples, the most important MRI findings that will assist the orthopedist in treatment selection and prognostication to ultimately determine if the patient is a candidate for surgery and if so, the most appropriate surgical treatment.

Educational Goals / Teaching Points
At the end of this educational exhibit, the reader will be able to understand the natural history of RCTs and in particular the surgical challenge presented by massive RCTs (> 5 cm in mediolateral diameter), become familiar with available surgical options, and be able to identify and describe the five most important imaging factors affecting choice of operation and surgical outcome.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The following five most important MRI features will be discussed with imaging examples including the number of tendons demonstrating full thickness tears with special attention to full thickness tear of the subscapularis tendon, size of tear in mediolateral (ML) and anteroposterior (AP) orientations, degree of retraction as quantified by the Patte Stage and the acromiohumeral distance and the influence these parameters have on operative considerations, fatty replacement as measured using the modified Gautallier Fatty Index and muscle atrophy as evaluated using the tangent sign and occupation grade, presence or absence of cuff arthropathy, and patient factors including age, preoperative functional status and the presence or absence of pseudoparalysis and demands on and expectations for the repair.

RCT is a common and important pathology with a range of surgical treatment options. Treatment choice is dependent on patient and imaging factors. Knowledge of the most important MRI findings allows the radiologist to best assist the orthopaedic surgeon in surgical planning.