Objective:To evaluate the clinical efficacy of cannulated screws combined with suture anchor in the treatment of comminuted patellar fractures.Methods:A retrospective study was conducted to analyze the data of 72 patients who had been admitted to Department of Orthopaedics, The Second Hospital of Shanxi Medical University for comminuted patellar fractures between January 2020 and June 2023. The patients were divided into 2 groups based on the surgical techniques used. In group A of 34 patients subjected to fixation using cannulated screws combined with suture anchors, there were 22 males and 12 females with an age of 49 (39, 58) years, and 7 cases of AO type 34-C2 and 27 cases of AO type 34-C3. In group B of 38 patients subjected to fixation using cannulated screws combined with titanium cables, there were 19 males and 19 females with an age of 55 (40, 62) years, and 11 cases of AO type 34-C2 and 27 cases of AO type 34-C3. Comparisons were made between the 2 groups regarding general preoperative data, postoperative range of knee motion, fracture healing time, complications, soft tissue irritation, secondary surgery, postoperative pain assessed by visual analogue scale (VAS), postoperative Bostman knee score, and postoperative Levack knee score.Results:The 2 groups were comparable because there were no statistically significant differences in the general preoperative data and follow-up time between them ( P>0.05). There were no statistically significant differences between the 2 groups either in postoperative range of knee motion, fracture healing time, or Bostman knee score or Levack knee score at the last follow-up (all P>0.05). In group A, the VAS pain score and the rate of soft tissue irritation at the last follow-up were respectively 0.0 (0.0, 1.0) and 0% (0/34), significantly lower than those in group B [1.0 (0.0, 1.3) and 15.8% (6/38)] ( P<0.05). The overall incidence of complications and secondary surgery rate in group A were respectively 5.9% (2/34) and 2.9% (1/34), lower than those in group B [21.1% (8/38) and 15.8% (6/38)], but showing no statistically significant difference between the 2 groups ( P>0.05). Conclusions:In the treatment of comminuted patellar fractures, fixation using cannulated screws combined with both titanium cables and suture anchors can lead to comparable clinical efficacy, but fixation using cannulated screws and suture anchors can reduce soft tissue irritation, alleviate pain, and improve the quality of life of patients.

Biodegradable polyamines have long been studied as potential recombinant viral gene vectors. Spermine (SPE) is an endogenous tetra-amine with excellent biocompatibility yet poor gene condensation capacity. We have previously synthesized a polyspermine based on SPE and poly(ethylene glycol) (PEG) diacrylate (SPE-alt-PEG) for enhanced transfection performance, but the synthesized SPE-alt-PEG still lacked specificity towards cancer cells. In this study, folic acid (FA) was incorporated into SPE-alt-PEG to fabricate a targeted gene delivery vector (FA-SPE-PEG) via an acylation reaction. FA-SPE-PEG exhibited mild cytotoxicity in both cancer cells and normal cells. FA-SPE-PEG possessed higher transfection efficiency than PEI 25 K and Lipofectamine(®) 2000 in two tested cancer cell lines at functional weight ratios, and its superiority over untargeted SPE-alt-PEG was prominent in cells with overexpressed folate receptors (FRs). Moreover, in vivo delivery of green fluorescent protein (GFP) with FA-SPE-PEG resulted in highest fluorescent signal intensity of all investigated groups. FA-SPE-PEG showed remarkably enhanced specificity towards cancer cells both in vivo and in vitro due to the interaction between FA and FRs. Taken together, FA-SPE-PEG was demonstrated to be a prospective targeted gene delivery vector with high transfection capacity and excellent biocompatibility.