Radioprotection of Tendon Tissue via Crosslinking and Free Radical Scavenging

Ionizing radiation could supplement tissue bank screening to further reduce the probability of diseases transmitted by allografts if denaturation effects can be minimized. It is important, however, such sterilization procedures be nondetrimental to tissues. We compared crosslinking and free radical scavenging potential methods to accomplish this task in tendon tissue. In addition, two forms of ionizing irradiation, gamma and electron beam (e-beam), were also compared. Crosslinkers included 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and glucose, which were used to add exogenous crosslinks to collagen. Free radical scavengers included mannitol, ascorbate, and riboflavin. Radioprotective effects were assessed through tensile testing and collagenase resistance testing after irradiation at 25 kGy and 50 kGy. Gamma and e-beam irradiation produced similar degenerative effects. Crosslinkers had the highest strength at 50 kGy, EDC treated tendons had 54% and 49% higher strength than untreated, for gamma and e-beam irradiation respectively. Free radical scavengers showed protective effects up to 25 kGy, especially for ascorbate and riboflavin. Crosslinked samples had higher resistance to collagenase and over a wider dose range than scavenger-treated. Of the options studied, the data suggest EDC precrosslinking or glucose treatment provides the best maintenance of native tendon properties after exposure to ionizing irradiation

Rehabilitation Predictors of Clinical Outcome Following Revision ACL Reconstruction in the MARS Cohort.

BackgroundRevision anterior cruciate ligament (ACL) reconstruction has been documented to have worse outcomes than primary ACL reconstruction. The reasons remain varied and not completely understood.MethodsPatients undergoing revision ACL reconstruction were prospectively enrolled. Data collected included baseline demographics, surgical technique and pathological condition, prescribed rehabilitation instructions, and a series of validated patient-reported outcome instruments. Patients were followed for 2 years and asked to complete a set of outcome instruments identical to those completed at baseline. Subsequent surgical procedures on the ipsilateral knee were recorded. Regression analysis was used to control for age, sex, activity level, baseline outcome scores, and the above-mentioned rehabilitation-related variables in order to assess the factors affecting clinical outcomes 2 years after revision ACL reconstruction.ResultsA total of 843 patients met the inclusion criteria and were successfully enrolled, and 82% (695) were followed for 2 years. Two rehabilitation-related factors were found to influence outcome. First, patients who were prescribed an ACL brace for their return to sports had a significantly better Knee injury and Osteoarthritis Outcome Score (KOOS) for sports and recreational activities at 2 years (odds ratio [OR] =1.50, 95% confidence interval [CI] = 1.07 to 2.11; p = 0.019). Second, patients prescribed an ACL brace for the postoperative rehabilitation period were 2.3 times more likely to have subsequent surgery by 2 years (OR = 2.26, 95% CI = 1.11 to 4.60; p = 0.024). The odds of a graft rerupture were not affected by any type of brace wear.ConclusionsRehabilitation-related factors that the physician can control at the time of an ACL reconstruction have the ability to influence clinical outcomes at 2 years. Weight-bearing and motion can be initiated immediately postoperatively. Bracing during the early postoperative period is not helpful. Use of a functional brace early in the postoperative period was associated with an increased risk of a reoperation. Use of a functional brace for a return to sports improved the KOOS on the sports/recreation subscale.Level of evidencePrognostic Level I. See Instructions for Authors for a complete description of levels of evidence

Osteoarthritis Classification Scales: Interobserver Reliability and Arthroscopic Correlation

The MARS Group* Background: Osteoarthritis of the knee is commonly diagnosed and monitored with radiography. However, the reliability of radiographic classification systems for osteoarthritis and the correlation of these classifications with the actual degree of confirmed degeneration of the articular cartilage of the tibiofemoral joint have not been adequately studied. Methods: As the Multicenter ACL (anterior cruciate ligament) Revision Study (MARS) Group, we conducted a multicenter, prospective longitudinal cohort study of patients undergoing revision surgery after anterior cruciate ligament reconstruction. We followed 632 patients who underwent radiographic evaluation of the knee (an anteroposterior weight-bearing radiograph, a posteroanterior weight-bearing radiograph made with the knee in 45°of flexion [Rosenberg radiograph], or both) and arthroscopic evaluation of the articular surfaces. Three blinded examiners independently graded radiographic findings according to six commonly used systems-the Kellgren-Lawrence, International Knee Documentation Committee, Fairbank, Brandt et al., Ahlbäck, and Jäger-Wirth classifications. Interobserver reliability was assessed with use of the intraclass correlation coefficient. The association between radiographic classification and arthroscopic findings of tibiofemoral chondral disease was assessed with use of the Spearman correlation coefficient. Results: Overall, 45°posteroanterior flexion weight-bearing radiographs had higher interobserver reliability (intraclass correlation coefficient = 0.63; 95% confidence interval, 0.61 to 0.65) compared with anteroposterior radiographs (intraclass continue

Personalized medicine in psychiatry: problems and promises

The central theme of personalized medicine is the premise that an individual’s unique physiologic characteristics play a significant role in both disease vulnerability and in response to specific therapies. The major goals of personalized medicine are therefore to predict an individual’s susceptibility to developing an illness, achieve accurate diagnosis, and optimize the most efficient and favorable response to treatment. The goal of achieving personalized medicine in psychiatry is a laudable one, because its attainment should be associated with a marked reduction in morbidity and mortality. In this review, we summarize an illustrative selection of studies that are laying the foundation towards personalizing medicine in major depressive disorder, bipolar disorder, and schizophrenia. In addition, we present emerging applications that are likely to advance personalized medicine in psychiatry, with an emphasis on novel biomarkers and neuroimaging