Corrigendum: Coating of manganese functional polyetheretherketone implants for osseous interface integration.

[This corrects the article DOI: 10.3389/fbioe.2023.1182187.].

Coating of manganese functional polyetheretherketone implants for osseous interface integration.

Polyetheretherketone (PEEK) has been used extensively in biomedical engineering and it is highly desirable for PEEK implant to possess the ability to promote cell growth and significant osteogenic properties and consequently stimulate bone regeneration. In this study, a manganese modified PEEK implant (PEEK-PDA-Mn) was fabricated via polydopamine chemical treatment. The results showed that manganese was successfully immobilized on PEEK surface, and the surface roughness and hydrophilicity significantly improved after surface modification. Cell experiments in vitro demonstrated that the PEEK-PDA-Mn possesses superior cytocompatibility in cell adhesion and spread. Moreover, the osteogenic properties of PEEK-PDA-Mn were proved by the increased expression of osteogenic genes, alkaline phosphatase (ALP), and mineralization in vitro. Further rat femoral condyle defect model was utilized to assess bone formation ability of different PEEK implants in vivo. The results revealed that the PEEK-PDA-Mn group promoted bone tissue regeneration in defect area. Taken together, the simple immersing method can modify the surface of PEEK, giving outstanding biocompatibility and enhanced bone tissue regeneration ability to the modified PEEK, which could be applied as an orthopedic implant in clinical.

A dual-functional PEEK implant coating for anti-bacterial and accelerated osseointegration.

Polyetheretherketone (PEEK) has been widely applied in biomedical engineering. However, the unsatisfactory bioactivity essentially limits the clinical application of PEEK. In this study, a simply immersing method was proposed to fabricate a dual-functional PEEK with antibacterial properties and enhanced bone integration. Firstly, the surface of PEEK was modified with a polydopamine (PDA) coating by incubating at dopamine solution. Afterward, the PEEK-PDA was modified with manganese (Mn) and silver (Ag) ions by the soaking method to fabricate the PEEK-PDA-Mn/Ag. The physicochemical capabilities of PEEK-PDA-Mn/Ag were further explored in the ions release, wettability, morphology, and element distributions. PEEK-PDA-Mn/Ag obviously accelerated the adhesion and distribution of MC3T3-E1 cells, indicating favorable biosafety in vitro. Meanwhile, the osteogenic properties of PEEK-PDA-Mn and PEEK-PDA-Mn/Ag were proved by the increased expression of osteogenic genes, alkaline phosphatase (ALP), and mineralization in vitro. Additionally, the wide antibacterial capabilities of PEEK-PDA-Mn/Ag were proved in both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in vitro. Furthermore, the PEEK-PDA-Mn/Ag was antibacterial with capability in enhancing osseointegration in vivo. Overall, the simply immersing method can modify the surface of PEEK, giving the bioactivity, biocompatibility, and antibacterial ability to the composited PEEK, which could be applied as an orthopedic implant in clinical.

Comparative study of InterTAN and Dynamic Hip Screw in treatment of femoral intertrochanteric injury and wound.

The aim of this study is to compare the effects and complications of InterTAN nail versus Dynamic Hip Screw (DHS) in treatment of femoral intertrochanteric fractures. Between January 2006 and December 2013, a total of 75 patients with femoral intertrochanteric fractures were retrospectively reviewed. There were 16 cases of type A1, 51 cases of type A2, and 8 cases of type A3. 37 patients treated with InterTAN nail, and 38 with DHS. The clinic data of surgical trauma, postoperative function and complications were statistically compared in this study. This results indicated that 31 cases by InterTAN and 30 cases by DHS had obtained follow-up with mean time (11 ± 5.6) months. Operative time of InterTAN group is (23.1 ± 9.2) min, and of DHS group is (55.2 ± 14.5) min (P < 0.05). Intra-operative active blood loss is (70.1 ± 30.7) ml in InterTAN group, and (205.7 ± 40.7) ml in DHS group (P < 0.05). Fluoroscopy frequency of InterTAN group is (16.3 ± 4.4) times, and of DHS group is (25.1 ± 3.1) times (P < 0.05). Complications occurred in 3 cases (9.7%) in InterTAN group compared 6 cases (20%) in DHS group (P < 0.05). Two cases had hip varus in InterTAN group, and three cases in DHS group. One case had deep venous thrombosis (DVT) in InterTAN group, and one case in DHS group. In conclusion, InterTAN significantly reduce the operative time, fluoroscopy frequency, intra-operative active blood loss and postoperative complications. The InterTAN technical features make it applicable to the aged patient with variety of medical basic diseases and cases of osteoporotic and unstable fracture types.