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Objective: To establish reference values of rotator cuff (RC) cross sectional area (CSA) in males. Materials and methods: We retrospectively analyzed shoulder MRIs from 500 patients aged 13-78 years, grouped as follows (N=100 in each): <20, 20-30, 30-40, 40-50, >50 years. All examinations were reviewed to exclude prior surgery, tears, or significant RC pathology. We segmented a standardized T1 sagittal MR image in each case to obtain CSA of supraspinatus (SUP), infraspinatus/teres minor (INF), and subscapularis (SUB) muscles. Across age groups, we recorded individual and total muscle CSA. We also performed ratios between individual muscle CSA and total CSA to examine total muscle mass contribution over age groups. We tested for differences between age groups controlled for BMI. Results: CSAs for SUP, INF, SUB, and total RC CSA were lower in subjects >50 years compared to all other groups (P<0.003 for all comparisons), persisting after controlling for BMI (P<0.03). Relative contribution of SUP CSA to total RC CSA was stable across age groups (P>0.32). INF CSA relative to total RC CSA increased with age, whereas SUB decreased (P<0.005). Subjects >50 years showed lower SUP (-15%), INF (-6%), and SUB (-21%) CSA, when compared to mean CSAs of all subjects <50 years. Total RC CSA significantly correlated with age (r=-0.34, P<0.001), persisting after controlling for BMI (r=-0.42, P<0.001). Conclusion: RC muscles in male subjects with no tears on MRI show decreasing CSA with age, independent of BMI. [ABSTRACT FROM AUTHOR]

Purpose: Plant-based diets have become increasingly popular in Western culture. Although studies have examined physiologic health improvements of plant-based diets, there is little data on plant-based diets as it relates to sports performance. Methods: Clinical review of systematic reviews, randomized trials, prospective and retrospective cohort studies available in English on PubMed and Google Scholar databases utilizing combinations of the search terms "athlete, sport, nutrition, diet, vegan, vegetarian, strength, endurance, health, performance, and exercise." Results: There are no significant differences in athletic performance in participants maintaining plant-based diets compared to those consuming omnivorous diets specifically related to strength, power, and endurance. Plant-based diets are at higher risk of predisposing individuals to certain micronutrient deficiencies, reduced protein intake, and lower serum creatine and sex testosterone levels, though supplementation may effectively replace the lacking components. Non-plant-based diets are associated with a higher risk of obesity, type II diabetes mellitus, certain malignancies, and cardiovascular disease, though several studies demonstrate that a particular meat- and fish-filled diet may reduce body weight, blood pressure, fat composition, and all-cause mortality. Conclusion: Though plant-based and mixed omnivorous eaters may vary in their macronutrient and micronutrient intake, disease propensities, and oxygen consumption during exertion, a plant-based diet does not translate into a significantly different physical performance compared to a non-plant-based diet across measures of strength, power, and aerobic/anaerobic performance. For athletes, trainers, nutritionists and dieticians, and physicians, the most important recommendation is to maintain a nutritionally sufficient diet that provides the appropriate levels of vital nutrients and vitamins. [ABSTRACT FROM AUTHOR]

Purpose: Orthopedic literature remains divided on the utility of biologic augmentation to optimize outcomes after isolated meniscal repair. The aim of this systematic review is to analyze the clinical outcomes and re-operation rates of biologically augmented meniscal repairs.Methods: PubMed, CINAHL, Cochrane, and EMBASE databases were queried in October 2020 for published literature on isolated meniscal repair with biological augmentation. Studies were assessed for quality and risk of bias by two appraisal tools. Patient demographics, meniscal tear characteristics, surgical procedure, augmentation type, post-operative rehabilitation, patient reported outcome measures, and length of follow-up were recorded, reviewed, and analyzed by two independent reviewers.Results: Of 3794 articles, 18 met inclusion criteria and yielded 537 patients who underwent biologic augmentation of meniscal repair. The biologically augmented repair rates were 5.8-27.0% with PRP augmentation, 0.0-28.5% with fibrin clot augmentation, 0.0-12.9% with marrow stimulation, and 0.0% with stem cell augmentation. One of seven studies showed lower revision rates with augmented meniscal repair compared to standard repair techniques, whereas five of seven found no benefit. Three of ten studies found significant functional improvement of biologically augmented repair versus standard repair techniques and six of ten studies found no difference. There was significant heterogeneity in methods for biologic preparation, delivery, and post-operative rehabilitation protocols.Conclusion: Patients reported significant improvements in functional outcomes scores after repair with biological augmentation, though the benefit over standard repair controls is questionable. Revision rates after biologically augmented meniscal repair also appear similar to standard repair techniques. Clinicians should bear this in mind when considering biologic augmentation in the setting of meniscal repair.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Objective: To develop and validate a deep convolutional neural network (CNN) method capable of (1) selecting a specific shoulder sagittal MR image (Y-view) and (2) automatically segmenting rotator cuff (RC) muscles on a Y-view. We hypothesized a CNN approach can accurately perform both tasks compared with manual reference standards. Material and methods: We created 2 models: model A for Y-view selection and model B for muscle segmentation. For model A, we manually selected shoulder sagittal T1 Y-views from 258 cases as ground truth to train a classification CNN (Keras/Tensorflow, Inception v3, 16 batch, 100 epochs, dropout 0.2, learning rate 0.001, RMSprop). A top-3 success rate evaluated model A on 100 internal and 50 external test cases. For model B, we manually segmented subscapularis, supraspinatus, and infraspinatus/teres minor on 1048 sagittal T1 Y-views. After histogram equalization and data augmentation, the model was trained from scratch (U-Net, 8 batch, 50 epochs, dropout 0.25, learning rate 0.0001, softmax). Dice (F1) score determined segmentation accuracy on 105 internal and 50 external test images. Results: Model A showed top-3 accuracy > 98% to select an appropriate Y-view. Model B produced accurate RC muscle segmentations with mean Dice scores > 0.93. Individual muscle Dice scores on internal/external datasets were as follows: subscapularis 0.96/0.93, supraspinatus 0.97/0.96, and infraspinatus/teres minor 0.97/0.95. Conclusions: Our results show overall accurate Y-view selection and automated RC muscle segmentation using a combination of deep CNN algorithms. [ABSTRACT FROM AUTHOR]

Purpose: Knowledge of ulnar nerve position is of utmost importance to avoid iatrogenic injury in elbow arthroscopy. The aim of this study was to determine how accurate surgeons are in locating the ulnar nerve after fluid extravasation has already occurred, and basing their localization solely on palpation of anatomical landmarks.Methods: Seven cadaveric elbows were used and seven experienced surgeons in elbow arthroscopy participated. An arthroscopic setting was simulated and fluids were pumped into the joint from the posterior compartment for 15 min. For each cadaveric elbow, one surgeon was asked to locate the ulnar nerve solely by palpation of the anatomical landmarks, and subsequently pin the ulnar nerve at two positions: within 5 cm proximal and another within 5 cm distal of a line connecting the medial epicondyle and the tip of the olecranon. Subsequently, the elbows were dissected using a standard medial elbow approach and the distances between the pins and ulnar nerve were measured.Results: The median distance between the ulnar nerve and the proximal pins was 0 mm (range 0-0 mm), and between the ulnar nerve and the distal pins was 2 mm (range 0-10 mm), showing a statistically significant difference (p = 0.009). All seven proximally placed pins (100%) transfixed the ulnar nerve versus two out of seven distally placed pins (29%) (p = 0.021).Conclusions: In a setting simulating an already initiated arthroscopic procedure, the sole palpation of the anatomical landmarks allows experienced elbow surgeons to accurately locate the ulnar nerve only in its course proximal to the medial epicondyle (7/7, 100%), whereas a significantly reduced accuracy is documented when the same surgeons attempt to locate the nerve distal to the medial epicondyle (2/7, 29%; p = 0.021). Current findings support the establishment of a proximal anteromedial portal over a distal anteromedial portal to access the anterior compartment after tissue extravasation has occurred with regard to ulnar nerve safety. [ABSTRACT FROM AUTHOR]

Purpose: In this anatomical cadaver study, the distance between major nerves and ligaments at risk for injury and portal sites created by trainees was measured. Trainees, inexperienced in elbow arthroscopy, have received a didactic lecture and cadaver instruction prior to portal placement. The incidence of iatrogenic injury from novice portal placement was also determined.Methods: Anterolateral, direct lateral, and anteromedial arthroscopic portals were created in ten cadavers by ten inexperienced trainees in elbow arthroscopy. After creating each portal, the trajectory of the portal was marked with a guide pin. Subsequently, the cadavers were dissected and the distances between the guide pin in the anterolateral, direct lateral, and anteromedial portals and important ligaments and nerves were measured.Results: The difference between the distance of the direct lateral portal and the posterior antebrachial cutaneous nerve (PABCN) (22 mm, p < 0.001), the lateral antebrachial cutaneous nerve (4.0 mm, p < 0.001), and the radial nerve (25 mm, p < 0.001) was different from the average reported distances in the literature. A difference was found between the distance of the anterolateral portal and the PABCN (32 mm, p < 0.001) compared to previous studies. Three major iatrogenic complications were observed, including: laceration of the posterior bundle of the medial ulnar collateral ligament, lateral ulnar collateral ligament midsubstance laceration, and median nerve partial laceration.Conclusion: Surgeons increasingly consider arthroscopic treatment as an option for elbow pathology. In the present study a surgical complication rate of 30 % was found with novice portal placement during elbow arthroscopy. Furthermore, as the results from this study have indicated, accurate, precise, and safe portal placement in elbow arthroscopy is not easily achieved by didactic lecture and cadaver instruction session alone. Level of evidence V. [ABSTRACT FROM AUTHOR]

Purpose: To determine the rate of donor-site morbidity after osteochondral autologous transplantation (OATS) for capitellar osteochondritis dissecans.Methods: A literature search was performed in PubMed/MEDLINE, Embase, and Cochrane Library to identify studies up to November 6, 2016. Criteria for inclusion were OATS for capitellar osteochondritis dissecans, reported outcomes related to donor sites, ≥10 patients, ≥1 year follow-up, and written in English. Donor-site morbidity was defined as persistent symptoms (≥1 year) or cases that required subsequent intervention. Patient and harvest characteristics were described, as well as the rate of donor-site morbidity. A random effects model was used to calculate and compare weighted group proportions.Results: Eleven studies including 190 patients were included. In eight studies, grafts were harvested from the femoral condyle, in three studies, from either the 5th or 6th costal-osteochondral junction. The average number of grafts was 2 (1-5); graft diameter ranged from 2.6 to 11 mm. In the knee-to-elbow group, donor-site morbidity was reported in 10 of 128 patients (7.8%), knee pain during activity (7.0%) and locking sensations (0.8%). In the rib-to-elbow group, one of 62 cases (1.6%) was complicated, a pneumothorax. The proportion in the knee-to-elbow group was 0.04 (95% CI 0.0-0.15), and the proportion in the rib-to-elbow group was 0.01 (95% CI 0.00-0.06). There were no significant differences between both harvest techniques (n.s.).Conclusions: Donor-site morbidity after OATS for capitellar osteochondritis dissecans was reported in a considerable group of patients.Level Of Evidence: Level IV, systematic review of level IV studies. [ABSTRACT FROM AUTHOR]