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Background: Zirconium ceramics are one of the most controversial prosthetic biomaterials with good mechanical properties on the one hand, but early failure incidents on the other hand. A case of an early failure of zirconia femoral head in a 73-year-old clergy man, who underwent a total hip arthroplasty 28 months before, is reported., Method: The retrieved femoral head fragments, during revision surgery, were studied using scanning electron microscopy., Findings: Although a randomly occurred fracture without biomechanical significance can be a possible explanation, the collected data give evidence that initial non-critical microcracks or crazes due to contact stresses or strain mismatches or both between the ceramic head and the metallic tapered neck of the prosthesis led to the fatigue of the material. The final outcome was a catastrophic fracture of the head., Interpretation: Fixation of the neck into the zirconia head, with no mismatching or stress differences, would solve the fatigue-induced head destruction.

Objectives: To determine the safety of the use of Durasphere in patients receiving warfarin anticoagulation., Methods: This case series included patients requiring long-term anticoagulation who also had intrinsic sphincteric deficiency or mixed urinary incontinence, and bladder outlets without hypermobility. All patients, with the exception of the 1 man in the study, were treated under local anesthesia with periurethral carbon bead injections, while receiving therapeutic doses of warfarin., Results: Between 1999 and 2004, 20 such patients received carbon bead injections, on 36 different occasions, during therapeutic warfarin administration. Two complications related to the anticoagulation were encountered, one minor complication of a small periurethral hematoma and the other more severe, with a patient developing urinary retention and intravesical hemorrhage., Conclusions: In most cases, the injection of carbon beads under local anesthesia in patients receiving therapeutic warfarin anticoagulation can be safely performed without reversal of the anticoagulation.

Durasphere is a urethral bulking agent used to treat stress urinary incontinence secondary to intrinsic sphincter deficiency. Although rare, chronic outlet obstruction and urinary retention are possible complications of this "permanent" bulking agent. We describe the endoscopic evacuation of Durasphere causing bladder outlet obstruction 1 year after being injected.

A beta type titanium alloy, Ti-29Nb-13Ta-4.6Zr, was newly designed and developed for biomedical applications. The new alloy contains non-toxic elements such as Nb, Ta, and Zr. In the present study, phases that appeared in the new alloy through various aging treatments were characterized by hardness tests and microstructural observations in order to identify the phase transformation. Fatigue properties of the new alloy were investigated. Young's modulus and cyto-toxicity of the new alloy were also evaluated. Precipitated phases distribute homogeneously over the whole specimen, and they are alpha phase, a small amount of omega phase, and beta phase when the new alloys are subjected to aging treatment at 673K for 259.2ks after solution treatment at 1063K for 3.6ks. The fatigue strength of the new alloy subjected to aging at 673K for 259.2ks after solution treatment at 1063K for 3.6ks is much better than when subjected to other aging treatments. In this case, the fatigue limit is around 700MPa. Young's modulus of the new alloy is much smaller than that of Ti-6Al-4V ELI. The cyto-toxicity of the new alloy is equivalent to that of pure Ti. Therefore, it is proposed that the new alloy, Ti-29Nb-13Ta-4.6Zr, will be of considerable use in biomedical applications.

Objectives: To assess the safety and effectiveness of Durasphere compared with bovine collagen in the treatment of stress urinary incontinence (SUI) due to intrinsic sphincter deficiency (ISD)., Methods: This multicenter, randomized, controlled, double-blind trial was composed of 355 women diagnosed with SUI due to ISD and used a standardized pad test and the Stamey continence grade as the primary endpoints. The participants' ages ranged from 26 to 84 years. All patients had an abdominal leak point pressure of less than 90 cm H(2)O (average 51)., Results: At 12 months after the first injection, the two materials were equivalent with respect to the improvement in continence grade and pad weight testing. Less Durasphere was injected to obtain comparable clinical results (Durasphere 4.83 mL versus bovine collagen 6.23 mL, P <0.001). When examined 1 year after the date of the last treatment, 49 (80.3%) of the 61 women treated with Durasphere showed improvement of 1 continence grade or more compared with 47 (69.1%) of 68 women treated with bovine collagen (P value for difference = 0.162). Although the adverse events reported for both groups were similar, the Durasphere group had an increased short-term risk of urgency and urinary retention., Conclusions: The use of Durasphere for the treatment of SUI due to ISD was equally effective as bovine collagen and used less material. The U.S. Food and Drug Administration granted market approval for Durasphere on September 13, 1999. The product design and initial clinical data suggest the potential for greater durability of the clinical benefit, with the possibility of a permanent solution for SUI due to ISD in some patients.