Effect of a Semirigid Ankle Brace on the In Vivo Kinematics of Patients with Functional Ankle Instability during the Stance Phase of Walking

An ankle brace is commonly used by patients after they suffer from initial ankle sprains, reducing the incidents of recurrent sprain or limiting laxity in joints with functional ankle instability (FAI). However, whether the application of a semirigid ankle brace can improve the abnormal ankle gait kinematics of patients with FAI remains unknown. This study aimed to determine the effect of a semirigid ankle brace on the gait kinematics of ankle joints through 3D-2D fluoroscopy image registration. A total of 8 subjects with FAI (3 males and 5 females, 10 feet) as FAI group and 10 subjects without FAI (6 males and 4 females, 10 feet) as control group were enrolled in this study. Three-dimensional bone models created from computed tomography images were matched to fluoroscopic images to compute the 6 degrees of freedom (DOF) talocrural, subtalar, and ankle joints complex kinematics for control and FAI group with or without brace during the stance phase of walking. FAI patients had significantly less ROMs in inversion/eversion rotation of the talocrural and subtalar joint after wearing semirigid ankle brace. Laxity was observed in most of the displacements of the talocrural and subtalar joints in FAI group. The brace partly altered the ankle joints movement in opposite directions, especially joint rotation, and restricted the talocrural and subtalar joints in the dorsiflexion position during the touch down phase of walking

Tailoring the tribology property and corrosion resistance of selective laser melted CoCrMo alloys by varying copper content

In this study, the cobalt-chromium-molybdenum (CoCrMo) alloys containing varying Cu contents (CCM-xCu, x  = 0, 2, 3, 4 wt%) were fabricated via the selected laser melting (SLM) method. The influences of Cu content on tribological performance and corrosion resistance were investigated. The 2 and 3 wt% Cu contributed to inhibiting the generation of the HCP phase, whereas the inhibitory effect was quite limited at 4 wt% Cu. Notably, 4 wt% Cu led to the formation of Cr-enrich precipitates in the matrix, which was partially coherent with the Cu nanoparticle. The corrosion resistance of the CCM alloy was enhanced as the 2 and 3 wt% Cu added into the CCM alloy, contrarily, which deteriorated when Cu content reached 4 wt%. For the CCM-2Cu and CCM-3Cu, Cr-precipitates played a major role in enhancing the wear resistance, while the Cu lubrication effect working in coordination with Cr-precipitates determined that for the CCM-4Cu. This study was expected to achieve better tribology and corrosion properties of SLM-produced CCM alloys by tailoring microstructure through the Cu element

The Selective Transport of Ions in Charged Nanopore with Combined Multi-Physics Fields

The selective transport of ions in nanopores attracts broad interest due to their potential applications in chemical separation, ion filtration, seawater desalination, and energy conversion. The ion selectivity based on the ion dehydration and steric hindrance is still limited by the very similar diameter between different hydrated ions. The selectivity can only separate specific ion species, lacking a general separation effect. Herein, we report the highly ionic selective transport in charged nanopore through the combination of hydraulic pressure and electric field. Based on the coupled Poisson–Nernst–Planck (PNP) and Navier–Stokes (NS) equations, the calculation results suggest that the coupling of hydraulic pressure and electric field can significantly enhance the ion selectivity compared to the results under the single driven force of hydraulic pressure or electric field. Different from the material-property-based ion selective transport, this method endows the general separation effect between different kinds of ions. Through the appropriate combination of hydraulic pressure and electric field, an extremely high selectivity ratio can be achieved. Further in-depth analysis reveals the influence of nanopore diameter, surface charge density and ionic strength on the selectivity ratio. These findings provide a potential route for high-performance ionic selective transport and separation in nanofluidic systems

Comparison of Transforaminal Percutaneous Endoscopic Lumbar Discectomy with and without Foraminoplasty for Lumbar Disc Herniation: A 2-Year Follow-Up

Background. Both transforaminal percutaneous endoscopic lumbar discectomy with foraminoplasty (TF PELF) and transforaminal percutaneous endoscopic lumbar discectomy without foraminoplasty (TF PELD) were developed for lumbar disc herniation (LDH) patients. However, the safety and effectiveness between the TF PELF and TF PELD have not been investigated. Methods. Of the included 140 LDH patients, 62 patients received TF PELF (PELF group) and 78 patients received TF PELD (PELD group). The operation time, the duration of staying at the hospital, and complication incidences were recorded. All patients were followed up for 2 years, where low back and leg visual analogue scale (VAS) pain ratings and Oswestry Disability Index (ODI) were compared between the 2 groups before and after surgery. Modified Macnab criterion was estimated for all patients at postoperative 2 years. Results. There were no significant difference of the operation time, number of days staying at the hospital, and the incidence of complications between the 2 groups (P>0.05). Two cases in the PELF group and 1 case in the PELD group received a second surgery due to unrelieved symptoms postoperatively. Low back and leg VAS and ODI scores decreased in both groups after operation (P0.05). Six patients in the PELF group and 3 patients in the PELD group did not continue the follow-up; thus, only 131 patients completed Macnab evaluation. The satisfactory rate was reported as 80.4% in the PELF group and 90.7% in the PELD group (P>0.05). Conclusions. This study suggested that the safety and effectiveness of TF PELF are comparable to TF PELD for LDH patients