Treatment of nonunion after femoral neck fracture with valgus intertrochanteric osteotomy: a case report with 18-year follow-up.

We herein report the long-term effect of valgus intertrochanteric osteotomy for nonunion after femoral neck fracture. In this report, we describe our experience using valgus intertrochanteric osteotomy to treat nonunion after femoral neck fracture in a 20-year-old woman. The patient was discharged from the hospital 10 days after the operation, the internal fixation device was removed 1 year after the operation, and the patient was then followed up for 18 years. Valgus intertrochanteric osteotomy can effectively treat nonunion after adductive femoral neck fracture.

High-precision processing method for an aluminum mirror assisted with a femtosecond laser.

At present, aluminum-based optical payloads are widely used in the aviation and aerospace field, and the demand for aluminum mirrors has become increasingly urgent in the visible light region. The main processing of an aluminum alloy mirror involves single-point diamond turning followed by a combined polishing process. Among these processes, magnetorheological finishing (MRF) is an important method for improving a surface figure. During the MRF process, excessive impurity contaminants are introduced into the surface of the aluminum mirror, thereby reducing surface reflectivity. In this paper, theoretical analysis and time-of-flight secondary ion mass spectrometry depth profiling were used to obtain the cause of pollution, and the process scheme of femtosecond laser cleaning was proposed. After verifying the feasibility, a new, to the best of our knowledge, process route was implemented on a Φ50mm aluminum mirror. Finally, the surface figure of RMS 0.022λ and the surface roughness of Ra 3.24 nm were obtained. In addition, reflectance in the visible light and near-infrared bands has increased by about 50%.

Efficacy and safety of local infiltration analgesia for pain management in total knee and hip arthroplasty: A meta-analysis of randomized controlled trial.

BACKGROUND: Local infiltration analgesia (LIA) has become popular in postoperative pain relief after total hip arthroplasty (THA) or total knee arthroplasty (TKA). The aim of this meta-analysis was to compare the efficacy and safety of LIA with intrathecal morphine and epidural analgesia after THA and TKA. METHODS: A systematic article search was performed from PubMed, Embase, and Web of Science databases, up to February 21, 2019. The main outcomes included visual analog scale for assessment of pain, morphine equivalent consumption, length of hospital stay, and adverse events. The data were calculated using weight mean difference (WMD) or risk ratio (RR) with 95% confidence intervals (95% CIs). RESULTS: Eleven studies with a total of 707 patients met the inclusion criteria and were included in this meta-analysis. LIA provided better pain control than other 2 techniques at 24-hour (WMD = 10.61, 95% CI: 3.36-17.87; P = .004), 48-hour (WMD = 16.0, 95% CI: 8.87-23.13; P < .001), and 72-hour (WMD = 11.31, 95% CI: 3.78-18.83; P < .001). Moreover, LIA had similar morphine consumption and duration of hospital stay with intrathecal morphine and epidural analgesia. There was significantly lower incidence of adverse events with LIA than with the other 2 techniques. CONCLUSION: LIA provided better postoperative pain control and less adverse events than intrathecal morphine and epidural analgesia after THA and TKA.

Study on the surface crystallization mechanism and inhibition method in the CMP process of aluminum alloy mirrors.

Owing to its material properties, aluminum-based optical loads are widely used in the aerospace field. At present, the main processing of an aluminum alloy mirror is single-point diamond turning followed by the combined polishing process. The surface will generate some white crystals during the chemical mechanical polishing process (CMP). These crystals can affect the improvement of surface quality and seriously reduce the processing efficiency of the whole process. In view of the above problems, four main factors of crystallization are obtained by interface theoretical analysis, Visual MINTEQ simulation of chemical morphological distribution, and experimental analysis. They are temperature, PH value of polishing fluid, solid-liquid contact angle, and impurity content of aluminum alloy. The crystallization phenomenon in the polishing process is successfully suppressed by improving the polishing process and selecting new materials. The experimental results showed that the surface roughness decreased from 7.21 to 2.98 nm without crystallization using the new method.

Risk Factors for Surgical Site Infection After Spinal Surgery: A Systematic Review and Meta-Analysis Based on Twenty-Seven Studies.

BACKGROUND: The present meta-analysis was conducted to explore and identify the risk factors for surgical site infection (SSI) after spinal surgery based on qualified studies and to gain insight into the management of SSI among patients undergoing spinal surgery. METHODS: We searched the following electronic databases, PubMed, the Cochrane Library, and the Embase database, updated to May 2018, to identify eligible studies according to the index words with associated publications. The odds ratios and 95% confidence intervals were used to analyze the main outcomes. RESULTS: We found 27 studies with a total of 2175 patients in the SSI group and 41,536 patients in the control group for the present meta-analysis. The pooled results revealed that the risk factors for SSI included diabetes, obesity, hypertension, ≥3 hours operative time, and transfusion. In addition, no significant association was found between SSI and the following risk factors: female gender, age >60 years, smoking habit, bone autograft, bone allograft, prophylactic antibiotics, and steroid therapy. CONCLUSIONS: Our findings provide evidence that diabetes, obesity (body mass index >30 kg/m2), hypertension, ≥3 hours operative time, and transfusion have a strong association with a remarkable increase in the risk of SSI after spinal surgery. In conclusion, more high-quality trials with larger sample sizes and long-term randomized controlled trials are warranted to confirm the risk factors for SSI among patients undergoing spinal surgery.

Fringe discretization and manufacturing analysis of a computer-generated hologram in a null test of the freeform surface.

A computer-generated hologram (CGH) is the core component for an aspheric surface test. According to fabrication demands, it is necessary to convert the designed CGH phase compensation function into the processed pattern, that is, the fringe discretization process. In this paper, we propose a new discretization method for a CGH in a test of the freeform surface, and realized the encoding of processed fringes by MATLAB software. Furthermore, we designed the experiment to verify the accuracy of the new discretization method and compared the calculation efficiency between the new algorithm and the reported algorithm. Finally, based on the testing requirement of a freeform mirror in a camera optical system, we completed the design, encoding, and fabrication of the CGH sample, and analyzed the influence of various errors on wavefront accuracy of the CGH.