Oocyte morphology and estrogen concentrations following a reduction in progesterone in beef cattle

Low dosages of progestogens promote persistent follicles, high systemic estrogen and low fertility. The objectives of this study were to determine effects of a reduction in progesterone on (1) morphology of oocytes and intrafollicular concentrations of estradiol. Cows on low progesterone (n = 12) received used intravaginal progesterone inserts on d 4 after estrus and prostaglandin (PG) F2alpha (25 mg, i.m.) on d 6. Control animals (n = 12) received saline on d 6. The oocyte and follicular fluid were recovered from the largest follicle on d 8 or d 10.;Serum estradiol was lower during d 4--6 but greater (P \u3c .01) during d 7--10 in cows treated with progesterone inserts and PGF 2alpha while the largest follicle was larger in treated cows on day 10 only (14 vs. 12 mm; P \u3c .05). Intrafollicular concentrations of estrogen were greater in treated than in control cows (990 +/- 87 vs 191 +/- 106; P \u3c .01). Progesterone in follicular fluid (mean = 42 ng/ml) did not differ. Oocytes were observed in oocyte nuclear stage I in the control group on d 8. All other oocytes were in nuclear stage II. In addition, the degree of clumping of mitochondria, the percentage of intact cumulus cell processes and percentage of normally shaped mitochondria was greater in oocytes from d 8 control cows than in all other groups.;Changes in concentrations of estradiol and oocyte morphology typically associated with the preovulatory period had occurred within 2 d after a reduction in progesterone, even when low peripheral concentrations of progesterone were maintained. These earliest stages of oocyte maturation occurred in response to a reduction in progesterone. Similar changes in oocyte morphology were observed in control animals by d 10 of the estrous cycle, probably representing the onset of atresia

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