Total ankle replacement versus ankle fusion for end-stage ankle arthritis: A meta-analysis.

PURPOSE: This study aims to systematically review the efficacy and safety of total ankle replacement (TAR) and ankle fusion (AF) as treatment options for end-stage ankle arthritis. METHODS: A comprehensive literature search was conducted on data from multiple databases, including PubMed, The Cochrane Library, Construction and Building Materials, Embase, Web of Science, and Scopus for RCTs and prospective cohort studies comparing TAR and AF in patients with end-stage ankle arthritis from inception up to June, 2023. Our primary outcomes of interest included patients' clinical function scores and complications. We employed Review Manager 5.4 and Stata/MP 14.0 software for the meta-analysis. RESULTS: Our analysis incorporated 13 comparative studies, including 11 prospective studies, one pilot RCT, and one RCT. The pooled results revealed no significant difference in postoperative Short Form-36 scores between the TAR and AF groups (MD = -1.19, 95% CI: -3.89 to 1.50, p = .39). However, the postoperative Foot and Ankle Ability Measure scores in the AF group were significantly higher than in the TAR group (MD = 8.30, 95% CI: 1.01-15.60, p = .03). There was no significant difference in postoperative complication rates between the TAR and AF groups (RR = 0.95, 95% CI: 0.59 to 1.54, p = .85). CONCLUSION: Currently available evidence suggests no significant disparity in postoperative outcomes between TAR and AF. In the short term, TAR demonstrates better clinical scores than AF and lower complication rates. Conversely, in the long term, AF exhibits superior clinical scores and lower complication rates, although this difference is not statistically significant.

Enhanced mechanic properties of calcium phosphate cements via mussel-inspired adhesive as bone substitute: Highlights of their interactions.

BACKGROUND: Inspired by natural bones, many organic components were added to Calcium Phosphate Cements (CPCs) to improve their mechanical strength. However, the strength of these composite CPCs is limited by the low strength of organic components itself and the weak interaction between organic components and CPCs. OBJECTIVE: Firstly, a composite CPC containing mussel-inspired adhesive, Poly-(Dopamine Methacrylamide-co-2-methoxy Ethylacrylate) (pDM) was developed. Secondly, the interactions between pDM and CPC and their effect on mechanical properties were investigated. METHODS: The interactions between pDM and CPC were performed by Nuclear Magnetic Resonance, Laser Raman, X-ray Photoelectron Spectroscopy, Fourier Transform-Infrared Spectroscopy and X-ray Diffraction Analysis. RESULTS: The toughness and compressive strength of pDM-CPC scaffold were both significantly enhanced, because of the enhanced interface binding strength among CPC and pDM due to their interaction and the improved mechanical strength of pDM owing to its self-oxidation cross-linking. The toughness of pDM-CPC scaffolds increased with the increased contents of pDM, while pDM-CPC scaffold containing 35 wt.% pDM had the highest compressive strength of all, which the latter was more than five times compared to that of CPC. CONCLUSION: The mechanically strong pDM-CPC scaffolds has potential application in bone regeneration as well as in craniofacial and orthopedic repair.

Natural polymer derived hydrogel bioink with enhanced thixotropy improves printability and cellular preservation in 3D bioprinting.

Three-dimensional (3D) bioprinting is evolving into a promising technology by spatially controlling the distribution of living cells for the biomedical field. However, maintaining high printability while protecting cells from damage due to shear stress remains the key challenge for extrusion-based 3D bioprinting. Herein, we developed a novel "protein-polyphenol-polysaccharide" extrusion-based bioink named Gel-TA-Alg@Ca2+ using gelatin (Gel), tannic acid (TA) and sodium alginate (Alg) with quantitative thixotropy by pre-crosslinking with a series of low concentrations of CaCl2 at 0.03, 0.04, 0.05 and 0.06 M, respectively. Our experimental design quantitatively presented the positive proportional functional relationship between the thixotropy of Gel-TA-Alg@Ca2+ and printability (including injectability and formability) for the first time. Importantly, the thixotropy proportionately and significantly elevated cellular viability after 3D bioprinting due to the reduced extrusion force involved in printing. 3D bioprinted constructs composed of Gel-TA-Alg@Ca2+ and MG-63 cells exhibited a good cell viability rate for more than 14 days. These findings provide valuable insights into the rational design of thixotropic bioink and offer more opportunities to probe the relationship between the thixotropy and the success of 3D bioprinting.