Vaccination With Detoxified Leukocidin AB Reduces Bacterial Load in a Staphylococcus aureus Minipig Deep Surgical Wound Infection Model.

Vaccines against Staphylococcus aureus have eluded researchers for >3 decades while the burden of staphylococcal diseases has increased. Early vaccine attempts mainly used rodents to characterize preclinical efficacy, and all subsequently failed in human clinical efficacy trials. More recently, leukocidin AB (LukAB) has gained interest as a vaccine antigen. We developed a minipig deep surgical wound infection model offering 3 independent efficacy readouts: bacterial load at the superficial and at the deep-seated surgical site, and dissemination of bacteria. Due to similarities with humans, minipigs are an attractive option to study novel vaccine candidates. With this model, we characterized the efficacy of a LukAB toxoid as vaccine candidate. Compared to control animals, a 3-log reduction of bacteria at the deep-seated surgical site was observed in LukAB-treated minipigs and dissemination of bacteria was dramatically reduced. Therefore, LukAB toxoids may be a useful addition to S. aureus vaccines and warrant further study.

Concussions in Soccer: An Epidemiological Analysis in the Pediatric Population.

BACKGROUND: As the popularity of youth soccer has increased in the United States, more attention has been focused on the effect of concussion injuries, with recent debate on whether heading should be disallowed. There is little evidence examining the epidemiology of these injuries. PURPOSE/HYPOTHESIS: The purpose of this study was to examine the prevalence and incidence of youth soccer-related concussions. We hypothesized that concussion rates will correlate with increased participation in youth soccer. STUDY DESIGN: Descriptive epidemiology study. METHODS: The National Electronic Injury Surveillance System was used to collect data on concussion injuries that occurred during soccer in pediatric patients from 2008 through 2016. Soccer-related concussion injuries were identified using specific codes and were analyzed for variation in disposition. The types of contact were categorized into player-to-player, head-to-ball, player-to-post, and player-to-ground contacts. Contact types related to hospitalization were subanalyzed. RESULTS: A weighted total of 3285 concussion injuries were identified during the study period, with an average of 386 concussions each year. The average age was 13.5 years, and there were no differences seen in incidence between the sexes. The overall incidence of concussion injuries increased (r = 0.789), while hospitalizations decreased (r = -0.574). The most common cause of concussion was found to be player-to-player contact, followed by head-to-ground contact and then head-to-ball contact. Subanalysis showed that 13% of hospitalizations were due to head-to-ball contact, compared with 39% and 44% due to player-to-player contact and head-to-ground contact, respectively. The relative risk of hospitalization from a concussion due to head-to-ball contact was 7.06 compared with 22.60 due to head-to-ground contact. CONCLUSION: The incidence of concussion in youth soccer has been increasing over the past decade as predicted, given the growing participation rates in both male and female soccer players. The most common cause of concussion was player-to-player contact, and the majority of concussions resulting in hospitalization occurred because of head-to-ground contact.

Efficacy of Imaging Modalities Assessing Fatty Infiltration in Rotator Cuff Tears.

BACKGROUND: Fatty atrophy is a diagnosis characterized by the combination of fatty infiltration and muscle atrophy of the rotator cuff. Studies have shown a strong positive correlation between the level of fatty infiltration and the risk of experiencing a chronic rotator cuff tear. Therefore, the purpose of the present study was to review the current literature on radiographic imaging of fatty infiltration and fatty atrophy to better aid surgeons in predicting functional outcome and to help guide patient decisions. METHODS: We conducted a literature search in PubMed. The exact search queries included "rotator cuff" in the MeSH Terms field; "fatty atrophy," fatty infiltration," and "fatty muscle degeneration" in the Title/Abstract field; and various combinations of these searches. We initially found 184 articles using these keywords, including both human and animal studies. The 25 animal studies were excluded, leaving 159 articles. The abstracts of all remaining articles were reviewed and selected on the basis of our inclusion criteria of focusing on patients with rotator cuff tears (preoperatively and postoperatively), fatty infiltration, fatty atrophy, and imaging modalities. We excluded an additional 127 articles, leaving 32 articles that were selected for the final review and inclusion in this study. RESULTS: Among 45 shoulder specialists across different studies, interrater agreement for Goutallier staging with use of magnetic resonance imaging (MRI) ranged from 0.24 to 0.82 and intrarater agreement for supraspinatus fatty changes ranged from 0.34 to 0.89. Our review also showed strong positive correlations when assessing the severity of fatty atrophy of the rotator cuff between MRI and ultrasound or ultrasound modalities such as sonoelastography. CONCLUSIONS: Increasing fatty infiltration of the rotator cuff is associated with greater repair failure rates and hence poorer overall clinical outcomes. MRI remains the gold standard for the imaging of rotator cuff tears and postoperative healing. Ultrasound can decrease health-care expenditures associated with the assessment of repair integrity postoperatively, although ultrasound is not as precise and has some limitations compared with MRI.

Factors Affecting the Cost and Profitability of Arthroscopic Rotator Cuff Repair.

PURPOSE: To examine the cost metrics and profitability of rotator cuff repairs (RCRs) in a large health care system. METHODS: A retrospective study was performed using value analysis team data from 2 hospitals within a large metropolitan health system from 2010 to 2014. Cost and profit metrics were collected and compared against surgeon volume, surgeon subspecialty training, implant costs, Current Procedural Terminology (CPT) coding, length of stay, and hospital site. RESULTS: A total of 5,899 RCRs were identified with a mean contribution margin of $2,133. Surgical supplies were the largest contributor to direct costs. Hospital site also significantly affected contribution margin ($1,912 at hospital 1 vs $3,129 at hospital 2, P < .001). The number of billed CPT codes was not significantly correlated to contribution margin; however, significant differences were noted in contribution margin and direct cost associated with different CPT code combinations, with arthroscopic RCR with subacromial decompression and distal clavicle excision being the most profitable, at an average contribution margin of $2,147. There was no correlation between surgeon volume and contribution margin or direct cost. CONCLUSIONS: Our overall findings show that improvement in the profitability of arthroscopic RCR for hospital systems is possible, both by examining institutions' direct costs and by providing individual surgeons with cost breakdowns and contribution margin information to improve the profitability of their practice. LEVEL OF EVIDENCE: Level IV, economic and decision analysis.