Parylene scaffold for cartilage lesion.

Evaluate parylene scaffold feasibility in cartilage lesion treatment, introducing a novel paradigm combining a reparative and superficial reconstructive procedure. Fifteen rabbits were used. All animals had both knees operated and the same osteochondral lesion model was created bilaterally. The parylene scaffold was implanted in the right knee, and the left knee of the same animal was used as control. The animals were euthanized at different time points after surgery: four animals at three weeks, three animals at six weeks, four animals at nine weeks, and four animals at 12 weeks. Specimens were analyzed by International Cartilage Repair Society (ICRS) macroscopic evaluation, modified Pineda histologic evaluation of cartilage repair, and collagen II immunostaining. Parylene knees were compared to its matched contra-lateral control knees of the same animal using the Wilcoxon matched-pairs signed rank. ICRS mean ± SD values for parylene versus control, three, six, nine and twelve weeks, respectively: 7.83 ± 1.85 versus 4.42 ± 1.08, p = 0.0005; 10.17 ± 1.17 versus 6.83 ± 1.17, p = 0.03; 10.89 ± 0.60 versus 7.33 ± 2.18, p = 0.007; 10.67 ± 0.78 versus 7.83 ± 3.40, p = 0.03. Modified Pineda mean ± SD values for parylene versus control, six, nine and twelve weeks, respectively: 3.37 ± 0.87 versus 6.94 ± 1.7, p < 0.0001; 5.73 ± 2.05 versus 6.41 ± 1.7, p = 0.007; 3.06 ± 1.61 versus 6.52 ± 1.51, p < 0.0001. No inflammation was seen. Parylene implanted knees demonstrated higher collagen II expression via immunostaining in comparison to the control knees. Parylene scaffolds are a feasible option for cartilage lesion treatment and the combination of a reparative to a superficial reconstructive procedure using parylene scaffolds led to better results than the reparative procedure alone.

High Tibial Osteotomy Survivorship: A Population-Based Study.

BACKGROUND: High tibial osteotomy (HTO) was developed to treat early medial compartment osteoarthritis in varus knees. PURPOSE: To evaluate the midterm and long-term outcomes of HTO in a large population-based cohort of patients. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Data from the California Office of Statewide Health Planning and Development were used to identify patients undergoing HTO from 2000 to 2014. Patients with infectious arthritis, rheumatological disease, congenital deformities, malignancy, concurrent arthroplasty, or skeletal trauma were excluded. Demographic information was assessed for every patient. Failure was defined as conversion to total or unicompartmental knee arthroplasty. Differences between patients requiring arthroplasty and those who did not were identified using univariate analysis. Multivariate analysis was performed, and Kaplan-Meier survivorship estimates for 5- and 10-year survival were computed. RESULTS: A total of 1576 procedures were identified between 2000 and 2014; of these, 358 procedures were converted to arthroplasty within 10 years. Patients who went on to arthroplasty after HTO were older (48.23 ± 6.76 vs 42.66 ± 9.80 years, respectively; P < .001), had a higher incidence of hypertension (25.42% vs 17.82%, respectively; P = .001), and had a higher likelihood of having ≥1 comorbidity (38.0% vs 31.4%, respectively; P = .044). Patients were 8% more likely to require arthroplasty for each additional year in age (relative risk [RR], 1.08). Female patients were also at an increased risk of conversion to arthroplasty compared with male patients (RR, 1.38). Survivorship at 5 and 10 years was 80% and 56%, respectively, and the median time to failure was 5.1 years. CONCLUSION: HTO may provide long-term survival in select patients. Careful consideration should be given to patient age, sex, and osteoarthritis of the knee when selecting patients for this procedure.

Should antibiotics be administered before arthroscopic knee surgery? A systematic review of the literature.

AIM: To explore the current evidence surrounding the administration of prophylactic antibiotics for arthroscopic knee surgery. METHODS: Databases were searched from inception through May of 2018 for studies examining prophylactic antibiotic use and efficacy in knee arthroscopy. Studies with patient data were further assessed for types of arthroscopic procedures performed, number of patients in the study, use of antibiotics, and outcomes with the intention of performing a pooled analysis. Data pertaining to "deep tissue infection" or "septic arthritis" were included in our analysis. Reported data on superficial infection were not included in our data analysis. For the pooled analysis, a relative risk ratio was calculated and χ2 tests were used to assess for statistical significance between rates of infection amongst the various patient groups. Post hoc power analyses were performed to compute the statistical power obtained from our sample sizes. Number needed to treat analyses were performed for statistically significant differences by dividing 1 by the difference between the infection rates of the antibiotic and no antibiotic groups. An alpha value of 0.05 was used for our analysis. Study heterogeneity was assessed by Cochrane's Q test as well as calculation of the I 2 value. RESULTS: A total of 49682 patients who underwent knee arthroscopy for a diverse set of procedures across 19 studies met inclusion critera for pooled analysis. For those not undergoing graft procedures, there were 27 cases of post-operative septic arthritis in 34487 patients (0.08%) who received prophylactic antibiotics and 16 cases in 10911 (0.15%) who received none [risk ratio (RR) = 0.53, 95% confidence interval (CI): 0.29-0.99, P = 0.05]. A sub-group analysis in which bony procedures were excluded was performed which found no significant difference in infection rates between patients that received prophylactic antibiotics and patients that did not (P > 0.05). All anterior cruciate ligament reconstruction studies used prophylactic antibiotics, but two studies investigating the effect of soaking the graft in vancomycin in addition to standard intravenous (IV) prophylaxis were combined for analysis. There were 19 cases in 1095 patients (1.74%) who received IV antibioitics alone and no infections in 2034 patients who received IV antibiotics and had a vancomycin soaked graft (RR = 0.01, 95%CI: 0.001-0.229, P < 0.01). CONCLUSION: Prophylactic antibiotics are effective in preventing septic arthritis following simple knee arthroscopy. In procedures involving graft implantation, graft soaking reduces the rate of infection.