No abstract

The native extracellular matrix (ECM) biomaterial derived from small intestinal submucosa (SIS) is widely applied in tissue engineering for tissue repair and regeneration. SIS ECM is obtained through physical and chemical methods to remove the intrinsic cells, which would otherwise cause adverse immune reactions when the SIS ECM is implanted into the host body. Several research teams have reported diverse SIS decellularization methods. However, there was no consensus on the criteria to be used for the decellularization methods for SIS and further research on the mechanism action of SIS is needed for comprehensive detection of the biological composition. In this present study, we used three reported methods to prepare SIS and compared their effects on decellularization and the remaining biological components, microstructure and cytocompatibility. SIS prepared by the three kinds of decellularization methods all achieved the recommended criteria, had good biocompatibility and retained most active components. Nevertheless, regardless of which decellularization method was used, the microstructure and bioactive components of the prepared SIS were damaged in varying degrees. We recommend that researchers need to select a decellularization method that would be appropriate to use according to their research purposes. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 689–697, 2019.

Purpose It was the primary purpose of the present systematic review to identify the optimal protection measures during COVID-19 pandemic and provide guidance of protective measures for orthopedic surgeons. The secondary purpose was to report the protection experience of an orthopedic trauma center in Wuhan, China during the pandemic. Methods A systematic search of the PubMed, Cochrane, Web of Science, Google Scholar was performed for studies about COVID-19, fracture, trauma, orthopedic, healthcare workers, protection, telemedicine. The appropriate protective measures for orthopedic surgeons and patients were reviewed (on-site first aid, emergency room, operating room, isolation wards, general ward, etc.) during the entire diagnosis and treatment process of traumatic patients. Results Eighteen studies were included, and most studies (13/18) emphasized that orthopedic surgeons should pay attention to prevent cross-infection. Only four studies have reported in detail how orthopedic surgeons should be protected during surgery in the operating room. No detailed studies on multidisciplinary cooperation, strict protection, protection training, indications of emergency surgery, first aid on-site and protection in orthopedic wards were found. Conclusion Strict protection at every step in the patient pathway is important to reduce the risk of cross-infection. Lessons learnt from our experience provide some recommendations of protective measures during the entire diagnosis and treatment process of traumatic patients and help others to manage orthopedic patients with COVID-19, to reduce the risk of crossinfection between patients and to protect healthcare workers during work. Level of evidence IV.

Purpose Treatment options for adult spinal cord injury without radiographic abnormality (ASCIWORA) varied. Compression of ASCIWORA may more likely result from spinal cord lesions such as edema and hemorrhage or contusion. This study aimed to explore the clinical effect of early durotomy with duroplasty decompression in the treatment of severe ASCIWORA. Methods Data of 16 patients with ASCIWORA who underwent early (< 72 h) posterior laminectomy followed by durotomy with duroplasty decompression from June 2015 to January 2017 were retrospectively analyzed. Patients' prognosis was analyzed by American Spinal Injury Association Impairment Scale (AIS) grades and scores. In 3 patients, intraspinal pressure (ISP) was continuously monitored for 1 week. Results Cervical magnetic resonance imaging (MRI) revealed spinal cord edema in 9 patients and suspected hemorrhage or contusion in 7 cases. Pathological manifestations of spinal cord injury found during the operation were consistent with preoperative MRI findings. Of the 16 cases, AIS grade was improved by 1 grade in 3 cases, 2 grades in 11 cases, and 3 grades in 1 case. The AIS scores at the last follow-up were significantly higher than preoperative scores. There was a high level of ISP after laminectomy, whereas ISP continued to decrease steadily after durotomy. Conclusions Durotomy helps thoroughly decompress the spinal cord and improve cerebrospinal fluid circulation in severe ASCI-WORA cases. Cervical MRI and pathological investigation of the spinal cord can be used to evaluate and predict the prognosis of ASCIWORA patients. ISP monitoring is an effective method for evaluating intramedullary pressure and decompression.

No abstract

ABSTRACT:We investigated the effects of locally and systemically administered alendronate on wear debris-induced osteolysis in vivo. Endotoxin-free titanium particles were injected into rabbit femurs, prior to insertion of a nonweight-bearing polymethylmethacrylate plug into the distal femur canal. Then the particles were repeatedly injected into the knee 2, 4, and 6 weeks after the implantation. Alendronate was incorporated at three different concentrations (0.1, 0.5, and 1.0 wt %) into bone cement for local delivery. For systemic delivery, alendronate was subcutaneously injected (1.0 mg/kg/week) 1 week after the implantation and then once a week until sacrifice. Eight weeks postoperatively, there was significant evidence of osteolysis surrounding the plug in the control group compared with markedly blocked osteolysis in the 0.5 wt % and the 1.0 wt % groups, and the systemic group. There was a concentration-dependent effect of alendronate-loaded bone cement on the improvement of peri-prosthetic bone stock. Notably, no significant differences were found between the 0.5 wt % and the systemic group in peri-prosthetic bone stock and implant fixation. Collectively, although the biological efficacy after the systemic delivery of alendronate was slightly higher than that in the local treatment groups, alendronate-loaded bone cement may be therapeutically effective in inhibiting titanium particle-induced osteolysis in vivo. ß

BackgroundIliosacral screw fixation is a popular method for the management of posterior pelvic ring fractures or dislocations, providing adequate biomechanical stability. Our aim in this study was to describe the use of a new patient-specific external template to guide the insertion of iliosacral screws and to evaluate the efficacy and safety of this technique compared with the conventional fluoroscopy-guided technique.MethodsThis was a retrospective study of patients with incomplete or complete posterior pelvic ring disruptions who required iliosacral screw fixation. For analysis, patients were divided into two groups: the external template group (37 screws in 22 patients) and the conventional group (28 screws in 18 patients). The operative time per screw, radiation exposure time and the rate of screw perforation (accuracy) were compared between groups. In the external template group, the difference between the actual and planned iliosacral screw position was also compared.ResultsIn the conventional group, the average operative time per screw was 39.7 ± 10.6 min, with an average radiation exposure dose of 1904.0 ± 844.5 cGy/cm2, with 4 cases of screw perforation. In the external template group, the average operative time per screw was 17.9 ± 4.7 min, with an average radiation exposure dose of 742.8 ± 230.6 cGy/cm2 and 1 case of screw perforation. In the template group, the mean deviation distance between the actual and planned screw position was 2.75 ± 1.0 mm at the tip, 1.83 ± 0.67 mm in the nerve root tunnel zone and 1.52 ± 0.48 mm at the entry point, with a mean deviation angle of 1.73 ± 0.80°.ConclusionsThe external template provides an accurate and safe navigation tool for percutaneous iliosacral screw insertion that could decrease the operative time and radiation exposure.

No abstract