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The purpose of this study was to evaluate the suitability of a plasma sprayed titanium porous coating on polished magnesia‐stabilized zirconia (Mg‐PSZ) ceramic surfaces. We hypothesized that diffusion bonding was responsible for the adhesion of the coating to the ceramic substrate. Mg‐PSZ tensile test coupons were vibratory polished (roughness Sa = 0.50 μm) or vibratory polished/lapped (Sa = 0.12 μm) before coating and testing. The exposed surfaces after tensile testing were examined by energy dispersive X‐ray (EDX) analysis. Mg‐PSZ shear test coupons were vibratory polished (Sa = 0.48 μm). As the surface roughness of the ceramic substrate decreased by a factor of 4.175, the coating tensile strength increased from 62.6 to 66.8 MPa, comparable to that of porous coated cobalt chromium (CoCr) and titanium (Ti‐6Al‐4V) coupons. EDX analyses found titanium everywhere on the ceramic surface after the titanium layer was pulled off with tensile testing, even on areas that appeared to be “clean” to the naked eye. This suggested that titanium oxide compounds were present at the interface, where the oxygen required could only result from diffusion bonding across the interface. Diffusion bonding may also explain the significantly higher amounts of zirconium on the coating surface that had been pulled off the smoother lapped ceramic coupons. The measured shear strength of porous‐coated ceramic coupons was significantly higher than that of CoCr and Ti‐6Al‐4V coupons. The superior adherence of the titanium coating to Mg‐PSZ suggests this process has great clinical potential in arthroplasty, especially for patients with metal sensitivity. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1925–1932, 2019.

Use of larger diameter femoral heads has emerged as a promising strategy to reduce the risk of dislocation after total hip arthroplasty, but thinning the walls of cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) acetabular liners to accommodate these larger heads may compromise the locking mechanism of the liner. The purpose of this study was to test the mechanical integrity of the locking mechanism in cross-linked and re-melted UHMWPE acetabular components with reduced wall thickness. The locking mechanism of cross-linked (100 kGy/re-melted) acetabular liners in sizes 50/28, 50/36, and 52/36 mm of 1 design was evaluated by lever-out tests and torsion tests. Torsion tests were performed at 2 angles to isolate the liner's locking tabs independent of the contribution of its central post. Lever-out testing demonstrated nominally reduced failure strength in 50/36-mm liners (13.3 N · m) compared with 50/28-mm liners (12.3 N · m; P=.0502), whereas the lever-out strength of 52/36-mm liners was 12.2±0.94 N · m. Failure torques were similar between 50/28- and 50/36-mm liners at 45° and 90°, but the failure torque of size 52/36-mm liners was significantly higher at each angle. The use of larger diameter femoral heads does not compromise the locking mechanism of thinned MicroSeal (Signal Medical Corp, Marysville, Michigan) acetabular liners. Use of a cross-linked UHMWPE acetabular liner, with a locking mechanism that is not compromised when the liner is thinned to a thickness of at least 2.86 mm, appears to be a biomechanically sound construct when articulated with large diameter femoral heads.

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intraoperative revision for malplaced screws during the index procedure. Results of 10 case series and a European registry show rates of pedicle screw placement accuracy (0 mm to ≤ 2 mm) between 95% and 100% with 3D O-arm surgical imaging with navigation compared to 84%-95% reported for various current practice options from multiple meta-analyses. In addition, accuracy rates of between 72% and 92% have been reported for 2D C-arm without navigation. Economic studies demonstrated 3D O-arm surgical imaging with navigation has the potential to reduce the cost of fusion procedures in Europe and the USA by negating the need for pre-operative and post-operative imaging associated with current standardof-care, reducing the need for reoperations for screw revision, shortening length of procedures and OR time. It has been estimated that it could reduce the cost of hospitalization for spinal surgery by at least 3.8%. ConClusions: Current evidence shows 3D O-arm surgical imaging with navigation substantially reduces the human and financial burden of patients during spinal stabilization surgery compared with standard practice. PMS11 Evaluating thE Efficacy of BioSiMilar inflixiMaB with thE acr50 rESPonSE in PatiEntS with rhEuMatoid arthritiS; a MEta-analySiS in BayESian fraMEwork