Material properties of common suture materials in orthopaedic surgery

Suture materials in orthopaedic surgery are used for closure of wounds, repair of fascia, muscles, tendons, ligaments, joint capsules, and cerclage or tension band of certain fractures. The purpose of this study was to compare the biomechanical properties of eleven commonly used sutures in orthopaedic surgery. Three types of braided non-absorbable and one type of braided absorbable suture material with different calibers (n=77) underwent biomechanical testing for maximum load to failure, strain, and stiffness. All samples were tied by one surgeon with a single SMC (Seoul Medical Center) knot and three square knots. The maximum load to failure and strain were highest for #5 FiberWire and lowest for #0 Ethibond Excel (p<0.001). The stiffness was highest for #5 FiberWire and lowest for #2-0 Vicryl (p<0.001). In all samples, the failure of the suture material occurred at the knot There was no slippage of the knot in any of the samples tested. This data will assist the orthopaedic surgeon in selection and application of appropriate suture materials and calibers to specific tasks.

Influence of stent type on hemodynamic depression after carotid artery stent placement

PURPOSE: To assess the effect of stent type on hypotension and bradycardia after carotid artery stent placement. MATERIALS AND METHODS: A retrospective analysis on a prospectively maintained database was conducted in 256 patients (126 men; mean age, 71.8 years +/- 8.6; 194 de novo lesions) undergoing carotid artery stent placement between January 1996 and January 2007 by using self-expanding stents. Braided Elgiloy stents (Wallstents) were used in 44 of the 256 patients (17.2%) and slotted-tube nitinol stents were deployed in 212 (82.8%). Bivariate and multivariable logistic regression models were used to determine the influence of stent design on procedural and 24-hour hypotension and bradycardia. RESULTS: Procedural hemodynamic depression (HD) was encountered in 73 of the 256 patients (28.5%) due to hypotension in 24 (9.4%), bradycardia in 12 (4.7%), or both in 37 (14.5%) patients. Rates of procedural hypotension were 11.3% with nitinol stents and 0% with braided Elgiloy stents (P = .0188). Persistent postprocedural HD occurred in 91 of the 256 patients (35.5%) due to hypotension in 40 patients (15.6%), bradycardia in 23 (9.0%), or both in 28 (10.9%). Within a multivariable analysis adjusted for clinically relevant factors affecting rates of HD, the use of braided Elgiloy stents was associated with a decreased rate of procedural hypotension (odds ratio: 0.165; 95% confidence interval: 0.038, 0.721; P = .017). Procedural hypotension and bradycardia were not correlated to incidence of major adverse events but were associated with an increased duration of hospital stay (P = .0059 and P = .0335, respectively). CONCLUSIONS: Nitinol stents are associated with a higher risk of hypotension as compared to braided Elgiloy stents during carotid artery stent placement.