Background: Recent epidemiologic reports have demonstrated rising injury rates in Major League Baseball (MLB) and Minor League Baseball (MiLB). Although several studies have recently been published on specific injuries, the majority of injuries have not yet been formally studied. Purpose: The purpose of this study is to (1) generate a summative analysis of all injuries that occur in MLB and MiLB, (2) identify the 50 most common injuries, and (3) generate focused reports and fact sheets on the characteristics of each of those diagnoses. Study Design: Case series; Level of evidence, 4. Methods: The MLB Health and Injury Tracking System was used to identify injuries occurring in MLB and MiLB players from 2011 to 2016. Injuries were defined as those that occurred during normal baseball activity and resulted in at least 1 day out of play. A multitude of player and injury characteristics were analyzed, and detailed reports of the 50 most commonly occurring injuries were generated. Results: A total of 49,955 injuries occurred during the study period; 45,123 were non–season ending, and they resulted in 722,176 days out of play. The mean (median) days missed per injury was 16 (6) days. Overall, 39.1% of all injuries occurred in pitchers. The upper extremity was involved in 39% of injuries, while 35% occurred in the hip/groin/lower extremity. Surgery was required in 6.5% of cases, and 9.7% of injuries were season ending. Hamstring strains were the most common injury (n = 3337), followed by rotator cuff strain/tear (n = 1874), paralumbar muscle strain (n = 1313), biceps tendinitis (n = 1264), oblique strain (n = 1249), and elbow ulnar collateral ligament injury (n = 1191). The diagnoses that were most likely to end a player’s season were elbow ulnar collateral ligament injury (60% season ending) and superior labrum anterior and posterior tear (50.9% season ending). Conclusion: Contrary to prior reports relying on disabled list data, the annual number of injuries in professional baseball remained steady from 2011 to 2016. Similar trends were noted for the annual number of days missed and mean days missed per injury. Although the mean days missed per injury was high (16), the median was much lower at 6 days.
Osseous Vascularity of the Medial Elbow After Ulnar Collateral Ligament Reconstruction: A Comparison of the Docking and Modified Jobe Techniques
Background: Although vascularity plays a critical role in healing after ulnar collateral ligament (UCL) reconstruction, intraosseous blood flow to the medial epicondyle (ME) and sublime tubercle remains undefined. Purpose: To quantify vascular disruption caused by tunnel drilling with the modified Jobe and docking techniques for UCL reconstruction. Study Design: Controlled laboratory study. Methods: Eight matched pairs (16 specimens) of fresh-frozen cadaveric upper extremities were randomized to 1 of 2 study groups: docking technique or modified Jobe technique. One elbow in each pair underwent tunnel drilling by the assigned technique, while the contralateral elbow served as a control. Pregadolinium and postgadolinium magnetic resonance imaging were performed to quantify intraosseous vascularity within the ME, trochlea, and proximal ulna. Three-dimensional computed tomography (CT) and gross dissection were performed to assess terminal vessel integrity. Results: Ulnar tunnel drilling had minimal impact on vascularity of the proximal ulna, with maintenance of >95% blood flow for each technique. Perfusion in the ME was reduced 14% (to 86% of baseline) for the docking technique and 60% (to 40% of baseline) for the modified Jobe technique (mean difference, 46%; P = .029). Three-dimensional CT and gross dissection revealed increased disruption of small perforating vessels of the posterior aspect of the ME for the modified Jobe technique. Conclusion: Although tunnel drilling in the sublime tubercle appears to have a minimal effect on intraosseous vascularity of the proximal ulna, both the docking and modified Jobe techniques reduce flow in the ME. This reduction was 4 times greater for the modified Jobe technique, and these findings have important implications for UCL reconstruction surgery. Clinical Relevance: As the rate of revision UCL reconstructions continues to rise, investigation into causes for failure of primary surgery is needed. One potential cause is poor tendon-to-bone healing due to inadequate vascularity. This study quantifies the amount of vascular insult that is incurred in the ME during UCL reconstruction. While vascular insult is only one of many factors that affects the surgical success rate, surgeons performing this procedure should be mindful of this potential for vascular disruption.
Quantitative Anatomic Analysis of the Medial Ulnar Collateral Ligament Complex of the Elbow
Background: A more detailed assessment of the anatomy of the entire medial ulnar collateral ligament complex (MUCLC) is desired as the rate of medial elbow reconstruction surgery continues to rise. Purpose: To quantify the anatomy of the MUCLC, including the anterior bundle (AB), posterior bundle (PB), and transverse ligament (TL). Study Design: Descriptive laboratory study. Methods: Ten unpaired, fresh-frozen cadaveric elbows underwent 3-dimensional (3D) digitization and computed tomography with 3D reconstruction. Ligament footprint areas and geometries, distances to key bony landmarks, and isometry were determined. A surgeon digitized the visual center of each footprint, and this location was compared with the geometric centroid calculated from the outline of the digitized footprint. Results: The mean surface area of the AB was 324.2 mm 2 , with an origin footprint of 32.3 mm 2 and an elongated insertional footprint of 187.6 mm 2 (length, 29.7 mm). The mean area of the PB was 116.6 mm 2 (origin, 25.9 mm 2 ; insertion, 15.8 mm 2 ), and the mean surface area of the TL was 134.5 mm 2 (origin, 21.2 mm 2 ; insertion, 16.7 mm 2 ). The geometric centroids of all footprints could be predicted within 0.8 to 1.3 mm, with the exception of the AB insertion centroid, which was 7.6 mm distal to the perceived center at the apex of the sublime tubercle. While the PB remained relatively isometric from 0° to 90° of flexion ( P = .606), the AB lengthened by 2.2 mm ( P < .001). Conclusion: Contrary to several historical reports, the insertional footprint of the AB was larger, elongated, and tapered. The TL demonstrated a previously unrecognized expansive soft tissue insertion directly onto the AB, and additional analysis of the biomechanical contribution of this structure is needed. Clinical Relevance: These findings may serve as a foundation for future study of the MUCLC and help refine current surgical reconstruction techniques.
Decreased Shoulder External Rotation and Flexion Are Greater Predictors of Injury Than Internal Rotation Deficits: Analysis of 132 Pitcher‐Seasons in Professional Baseball
Purpose The primary aims of this work were to (1) describe normal range of motion (ROM) profiles for elite pitchers, (2) describe the characteristics of shoulder and elbow injuries in professional pitchers over a 6‐year period in one Major League Baseball organization, and (3) identify ROM measures that were independently associated with a future shoulder or elbow injury. Methods Over 6 seasons (2010‐2015), a preseason assessment was performed on all pitchers invited to Major League Baseball Spring Training for a single organization. ROM measures included shoulder flexion, horizontal adduction, external rotation (ER), internal rotation, as well as elbow flexion and extension, were measured for both the dominant and nondominant arm, and total range of motion and deficits were calculated. All noncontact shoulder and elbow injuries were identified. Using multivariate binomial logistic regression analysis to control for age, height, weight, and all other ROM measures, the factors associated with an increased risk of subsequent shoulder or elbow injury were identified. Results A total of 53 shoulder (n = 25) and elbow (n = 28) injuries occurred during 132 pitcher seasons (n = 81 pitchers). The most significant categorical risk factor associated with increased elbow injury rates was the presence of a shoulder flexion deficit >5° (odds ratio [OR] 2.83; P = .042). For continuous variables, the risk of elbow injury increased by 7% for each degree of increased shoulder ER deficit (OR 1.07; P = .030) and 9% for each degree of decreased shoulder flexion (OR 1.09; P = .017). None of the measures significantly correlated with shoulder injuries. Conclusions Preseason shoulder ER and flexion deficits are independent risk factors for the development of elbow injuries during the upcoming season. Although prior work has supported the importance of reducing glenohumeral internal rotation deficits in pitchers, this study demonstrates that deficits in shoulder ER and flexion are more significant predictors of subsequent elbow injury. Level of Evidence Level III, retrospective comparative study.
Factors That Increase the Risk of Infection After Elbow Arthroscopy: Analysis of Patient Demographics, Medical Comorbidities, and Steroid Injections in 2,704 Medicare Patients
Purpose To use a national database to determine (1) the incidence of joint infection after elbow arthroscopy, (2) identify independent patient‐related risk factors for infection, and (3) determine the influence of concomitant intra‐articular corticosteroid injection on infection risk. Methods The 100% Medicare Standard Analytic Files were queried to identify patients who underwent elbow arthroscopy from 2005 to 2012. Postoperative elbow infections occurring within 6 months of surgery were identified using both International Classification of Diseases, 9th Revision codes for postoperative infection and Current Procedural Terminology codes for the surgical treatment of a postoperative infection. Patients were excluded if their initial arthroscopic procedure was performed for infection. A multivariate binomial logistic regression analysis was then used to evaluate patient‐related risk factors for postoperative infection. Results Of the 2,704 elbow arthroscopy cases identified, 42 (1.55%) developed a postoperative infection. The annual incidence of infections did not increase significantly over the course of the study ( P = .374). A number of patient demographics and medical comorbidities significantly increased the risk of infection. The most notable factors included age ≥ 65 years (odds ratio [OR] 2.38, P = .006), body mass index > 40 (OR 1.97, P = .024), tobacco usage (OR 1.80, P = .046), alcohol usage (OR 4.01, P < .001), diabetes mellitus (OR 2.10, P = .015), inflammatory arthritis (OR 2.81, P < .001), hypercoagulable disorder (OR 2.51, P = .015), and intra‐articular corticosteroid injection at the time of arthroscopy (OR 2.79, P = .006). Conclusions The annual number of elbow arthroscopies performed in the United States has increased steadily; however, the postoperative infection rate remained consistently low at 1.55%. There are a number of patient‐specific risk factors that increase this risk with OR ranging from 1.97 to 4.01. Similarly, patients who receive an intra‐articular corticosteroid injection at the time of surgery are nearly 3 times (OR 2.79) more likely to develop a postoperative infection. Level of Evidence Level III, case‐control study.
Basics of Elbow Arthroscopy Part I: Surface Anatomy, Portals, and Structures at Risk
Abstract As our knowledge and technology advance, the indications for elbow arthroscopy continue to grow rapidly. During this expansion, a number of new portals have been described and reported using variable nomenclature and location descriptions. Accordingly, a comprehensive review of these portals is warranted. Given the concern for potential iatrogenic injury to surrounding neurovascular structures, a discussion of these critical nerves and vessels is also timely. In this work, we review pertinent surface anatomy; portal nomenclature, locations, and utility; and review distances to the nearest structures at risk. Technique Video video See video under supplementary data.
Basics of Elbow Arthroscopy Part II: Positioning and Diagnostic Arthroscopy in the Supine Position
Abstract The field of elbow arthroscopy has evolved significantly since the procedure was first introduced more than 30 years ago. As our knowledge and understanding grows, numerous technical modifications have been made to improve the safety and efficacy of elbow arthroscopy. One of the most significant modifications is the change from the supine hanging position to the supine‐suspended position with the use of a mechanical arm holder. Currently, the supine‐suspended and lateral decubitus positions are the 2 most commonly used techniques. In this work, we discuss the history of the supine position, provide key points for proper patient positioning, and detail the steps of diagnostic elbow arthroscopy. It is our hope that this work will serve as an up‐to‐date review and summary of the most critical components of this procedure for emerging elbow arthroscopists. Technique Video video See video under supplementary data.
Basics of Elbow Arthroscopy Part III: Positioning and Diagnostic Arthroscopy in the Lateral Decubitus Position
Abstract In recent years, arthroscopy has gained popularity as a preferred treatment of a multitude of pathologies affecting the elbow. Since its initial description in 1985, many modifications have been made as our knowledge and technology have advanced. Currently, the majority of arthroscopic procedures are performed in either the lateral decubitus or supine suspended position. In this work, we discuss the history, patient positioning, and key steps for performing elbow arthroscopy in the lateral decubitus position. In addition to key steps, a number of strengths and limitations of this set up are discussed in detail. When properly executed, elbow arthroscopy can be performed in a safe and efficient manner with minimal risk to patients. Technique Video video See video under supplementary data.