RESUMEN
As the area and range of surgical treatments in the orthopedic field have expanded, the development of biomaterials used for these treatments has also advanced. Biomaterials have osteobiologic properties, including osteogenicity, osteoconduction, and osteoinduction. Natural polymers, synthetic polymers, ceramics, and allograft-based substitutes can all be classified as biomaterials. Metallic implants are first-generation biomaterials that continue to be used and are constantly evolving. Metallic implants can be made from pure metals, such as cobalt, nickel, iron, or titanium, or from alloys, such as stainless steel, cobalt-based alloys, or titanium-based alloys. This review describes the fundamental characteristics of metals and biomaterials used in the orthopedic field and new developments in nanotechnology and 3D-printing technology. This overview discusses the biomaterials that clinicians commonly use. A complementary relationship between doctors and biomaterial scientists is likely to be necessary in the future.
RESUMEN
This study investigated the time-dependent characteristics of acupuncture and analyzed the association between acupuncture utilization and mortality rates, readmission rates, and complications among ischemic stroke patients. Data from the National Health Insurance Service-National Sample Cohort 2.0 from South Korea were used to track patients with subacute and chronic ischemic stroke, who had survived more than one month after onset, between 2010 and 2013. A total of 2299 patients were followed up until 2015. At baseline, the acupuncture group (n = 195) and the control group (n = 2104) had similar ages (acupuncture group: 69.0 ± 11.1 years; control group: 68.5 ± 11.8 years), but the acupuncture group had more comorbidities (Charlson comorbidity index; acupuncture group: 4.7 ± 2.1, control group: 4.3 ± 2.4). According to time-dependent Cox regression survival analysis, acupuncture treatment was associated with low hazard ratios (HR) for death (HR: 0.32; 95% confidence interval (CI): 0.18-0.60), fewer composite complications (HR: 0.34; 95% CI: 0.21-0.53), and reduced urinary tract infection (HR: 0.24; 95% CI: 0.11-0.54). Many acupuncture session sensitivity analyses were performed to assess the robustness using different criteria to define the acupuncture group, and the results were consistent with those of the main analysis. Therefore, acupuncture treatment might be associated with lower mortality rates and the prevention of complications after ischemic stroke.