Impact of local steroid application on dysphagia after anterior cervical spine surgery: a meta-analysis.

INTRODUCTION: Dysphagia is one of the most common complications of anterior cervical spine surgery. Local steroid was widely used to reduce the postoperative swallowing pain. However, the effect of local steroid application on dysphagia after anterior cervical spine surgery was still uncertain. MATERIALS AND METHODS: We searched Medline (PubMed), Embase and the Cochrane Library on July 27, 2021 for studies investigating the effect of local steroid application on dysphagia after anterior cervical spine surgery from their date of inception to 2021. The relative risk or weighted mean difference with 95% confidence interval was recorded as a summary statistic consist of postoperative dysphagia, swallowing VAS scores, SWAL-QOL scores, PSTSI, and steroid related complications. RESULTS: This meta-analysis included 7 RCT studies involving 254 patients in the steroid group and 232 patients in the placebo group. Results showed local steroid group had less patients with dysphagia, lower swallowing VAS scores and less severe of prevertebral soft-tissue edema on the fourth day after surgery. No significant difference in non-fusion rate between the two groups was observed. And all included studies had no serious steroid related complications reported. CONCLUSIONS: The use of local steroid in anterior cervical spine surgery could reduce the early postoperative dysphagia without serious steroid related complication. However, the safety of local steroid application still need further studies with larger samples.

BMP9-induced osteogenetic differentiation and bone formation of muscle-derived stem cells.

Efficient osteogenetic differentiation and bone formation from muscle-derived stem cells (MDSCs) should have potential clinical applications in treating nonunion fracture healing or bone defects. Here, we investigate osteogenetic differentiation ability of MDSCs induced by bone morphogenetic protein 9 (BMP9) in vitro and bone formation ability in rabbit radius defects repairing model. Rabbit's MDSCs were extracted by type I collagenase and trypsin methods, and BMP9 was introduced into MDSCs by infection with recombinant adenovirus. Effects of BMP9-induced osteogenetic differentiation of MDSCs were identified with alkaline phosphatase (ALP) activity and expression of later marker. In stem-cell implantation assay, MDSCs have also shown valuable potential bone formation ability induced by BMP9 in rabbit radius defects repairing test. Taken together, our findings suggest that MDSCs are potentiated osteogenetic stem cells which can be induced by BMP9 to treat large segmental bone defects, nonunion fracture, and/or osteoporotic fracture.

Interleukin-4 and osteoprotegerin suppress polyethylene wear debris-induced osteolysis in a murine air pouch model / 南方医科大学学报

<p><b>OBJECTIVE</b>To test the effect of recombinant interleukin-4 (IL-4) and recombinant osteoprotegerin (OPG) in suppressing bone resorption induced by polyethylene wear particles..</p><p><b>METHODS</b>A cranial bone allograft was introduced into the air pouches induced on the back of BALB/c mice, followed by injection of 1 ml suspension of polyethylene particles into the pouches. The mouse models were then divided into 3 groups to receive injections of saline (control), IL-4 alone, or IL-4 and OPG into the pouches. The tissues were harvested 21 days after bone implantation for molecular and histological analyses.</p><p><b>RESULTS</b>Polyethylene wear particles-stimulated inflammatory responses (increased cellular infiltration and IL-1 and TNF production) were markedly reduced by IL-4 treatment either alone or combined with OPG (P<0.05). Polyethylene particles significantly increased tartrate-resistant acid phosphatase (TRAP) staining and bone absorption of the implanted bone graft, and IL-4 treatment, either alone or combined with OPG, obviously reduced the osteolysis induced by polyethylene particles (P<0.05).</p><p><b>CONCLUSION</b>IL-4 offers protection against polyethylene wear debris-induced inflammation and bone resorption in this mouse model. IL-4 combined with OPG can be a feasible and effective therapeutic approach to the treatment and prevention of polyethylene wear debris-associated osteolysis and aseptic loosening of the prosthetic components.</p>