Twenty percent of ankle fractures present with concomitant syndesmosis injury which results in poor clinical outcomes. Surgical stabilization of the syndesmosis can be achieved with either trans-syndesmotic screws or a suture-button device. The aim of this study is to investigate the clinical efficacy of suture-button fixation and trans-syndesmotic screw fixation in the treatment of ankle fracture combined with distal tibiofibular syndesmosis injury. A retrospective analysis was conducted by enrolling 76 patients with ankle fractures combined with distal tibiofibular syndesmosis injury who were admitted in our trauma center from January 2018 to January 2019, including 34 cases of suture button group and 42 cases of the syndesmotic screw group with a mean follow-up period of 16 ± 7 (range 12 to 21) months. The demographic data included gender, age, injury mechanism, AO classification and the operation duration were recorded, the radiographic and clinical outcomes were determined by tibiofibular clear space, tibiofibular overlap distance, complications, and the Olerud-Molander Ankle Score at the last follow-up. All the indexes were compared between the two groups to discover the related statistical differences. With the numbers available, no significant difference could be detected in the surgical duration, tibiofibular clear space, tibiofibular overlap distance, total complication rate, and middle-term Olerud-Molander Ankle scores between the two groups. However, the suture button fixation group showed higher early stage Olerud-Molander Ankle scores(p=.027) and shorter full weightbearing time(p=.018) than that of syndesmotic screw fixation group. Considering the outcomes, we conclude that the suture-button fixation not only shows equivalent efficacy to the traditional syndesmotic screw, but also has advantages of allowing early weight bearing, low requirements for routine removal.

Objective: This study aimed to compare the biomechanical stability and clinical efficacy of the Kirschner-wire (K-wire) tension band combined with patellar cerclage and an anchor-loop plate (ALP) in treating inferior-pole patellar fracture.Methods: The finite element model was established to analyze the mechanical properties of a K-wire tension band combined with patellar cerclage and ALP fixation in the treatment of inferior patellar pole fracture. The clinical data of 49 patients with patellar inferior-pole fracture (AO/OTA 34 A1) admitted to our hospital from January 2017 to July 2021 were retrospectively analyzed. Among these, 28 cases were fixed with ALPs (ALP group) and 21 cases were fixed with K-wire tension bands combined with patellar cerclage (K-wire group). By reviewing the medical records and follow-up results, we compared the operation time, final knee joint activity, incidence of secondary surgery, postoperative complications, and joint function recovery between the two groups.Results: The biomechanical analysis of the finite element model showed that the maximum displacement of the K-wire group was 1.87 times that of the ALP group. The maximum stress of the K-wire group was 1.34 times that of the ALP group. The maximum stress of the pole bone in the K-wire group was 13.89 times that of the ALP group. The average follow-up times of the K-wire group and ALP group were similar (p > 0.05), and the average ages of the two groups were similar (p > 0.05). The operation time of the ALP group was significantly shorter than that of the K-wire group (p < 0.05).The final knee joint activity of the ALP group was significantly greater than that of the K-wire group (p < 0.05). The Bostman patellar fracture function score of the ALP group was significantly better than that of the K-wire group at 3 and 9 months after operation (p < 0.05). Postoperative complications of the two groups included 1 case (3.6%) in the ALP group with internal fixation-stimulation complications and, in the K-wire group, 3 cases (14.3%) with internal fixation stimulation complications and 1 case (4.8%) with infection.Conclusion: The ALP and K-wire tension band combined with patella cerclage models were tested at 500 N, and no damage occurred, indicating that the newly designed ALP is safe in mechanical structure. The ALP has better therapeutic effect in biomechanical stability, postoperative complications, secondary surgery, and knee function. This technique is an effective method for the treatment of inferior-pole patellar fracture.

The bacterial colonization and poor osseointegration of Ti implants significantly compromise their applications in load-bearing bone repair and replacement. To endorse the Ti with both excellent bioactivity and antibacterial ability, we developed a microarc oxidation coating that was modified uniformly by hydroxyapatite (HA) nanodots arrays and loaded regionally with chitosan hydrogel containing ciprofloxacin. The bonding between the HA nanodots covered coating and the chitosan hydrogel is further enhanced via silanization and chemical grafting of glutaraldehyde. Benefiting from the regionally loaded structure of the chitosan hydrogel, the chitosan hydrogel unloaded area can promote the cell adhesion and proliferation with excellent bioactivity, though relatively low OD value of cck8 has been observed at the beginning of the cell culturing. Whereas, the OD value of cck8 rises with the prolongation of the cell culturing time due to the degradation of the regionally loaded chitosan hydrogel. With the help of the laden ciprofloxacin in chitosan hydrogels, the sample effectively sterilizes the bacterial with a bacteriostatic ring. Therefore, regional loading of chitosan hydrogel containing ciprofloxacin on the modified microarc oxidation coating is a good approach to endorse Ti with both excellent bioactivity and antibacterial ability.

Objective: This study aimed to introduce a new surgical method for the fixation of olecranon fractures, and to compare the biomechanical stability and clinical efficacy of Kirschner wire tension band and anchor loop plate (ALP) in the treatment of olecranon fractures.Methods: A finite element model was established to analyze the mechanical properties of Kirschner wire tension and anchor loop plate fixation for olecranon fracture. The clinical data of 53 patients with olecranon fractures admitted to our hospital from March 2016 to October 2021 were retrospectively analyzed. Among them, 22 cases were fixed with an anchor loop plate (ALP group), and 31 patients were fixed with the Kirschner wire tension band technique. By reviewing the medical records and follow-up results, the final elbow mobility, secondary surgery, postoperative complications and elbow function recovery Mayo score and DASH score were compared between the two groups.Results: The biomechanical analysis of the finite element model showed that under the load of 120 N, the maximum displacement of the Kirschner wire group was 1.09 times that of the ALP group, the maximum stress of the Kirschner wire group was 1.33 times that of the ALP group, and the maximum stress of the olecranon proximal bone of the Kirschner wire group was 2.17 times that of the ALP group. Under the load of 200 N, the maximum displacement of the Kirschner wire group was 1.19 times that of the ALP group. The overall maximum stress of the Kirschner wire group was 1.59 times that of the ALP group, and the maximum stress of the proximal olecranon bone of the Kirschner wire group was 1.99 times that of the ALP group. The average follow-up time of the Kirschner wire and anchor loop plate groups was similar (p > 0.05). The average age of the two groups was identical (p > 0.05). The final elbow mobility in the anchor loop plate group was significantly greater than in the Kirschner wire group (p < 0.05). The Mayo score of the anchor loop plate group was substantially higher than that of the Kirschner wire group at 3 and 12 months after operation (p < 0.05), and the DASH score was significantly lower than that of the Kirschner wire group (p < 0.05). Postoperative complications in the two groups: 1 case (4.5%) in the anchor loop plate group had difficulties with internal fixation stimulation, and no infection occurred; in the Kirschner wire group, 5 cases (16.1%) had complications of internal fixation stimulation, and 1 patient (3.2%) had an infection.Conclusion: The model of olecranon fracture fixed by anchor loop plate and Kirschner wire tension technique was tested under 120 and 200 N tension, and no damage was found, indicating that the newly designed anchor loop plate was safe in mechanical structure. The biomechanical stability of the anchor plate technique is more stable, so it is not easy to have postoperative complications such as fracture block cutting and internal fixation failure. And the secondary operation rate and elbow function have better results. This technique is an effective method for the treatment of olecranon fractures.

The purpose of this study was to compare the biomechanical stability of the Kirschner wire tension band combined with patellar cerclage and anchor loop plate ( ALP ) in the treatment of inferior patellar fracture with different fracture lines and to provide a new solution for the treatment of sleeve avulsion fracture of the inferior pole of the patella. The finite element model was established, and the lower pole fractures of different fracture block sizes were graded according to the distribution of the lower pole fracture line. The model was subjected to finite element mechanical test under 500 N tensile load to test the biomechanical properties of Kirschner wire tension band combined with patellar cerclage anchor nail loop plate fixation for the treatment of patellar lower pole fractures with different fracture lines. The clinical data of 8 patients with sleeve avulsion fracture of the inferior pole of the patella admitted to our hospital from June 2018 to June 2022 were retrospectively analyzed. All patients were treated with a newly designed anchor loop plate. The safety and effectiveness of this new technique in the treatment of sleeve avulsion fracture of the inferior pole of the patella were analyzed. The safety activity of passive flexion and extension of the knee joint during the operation was observed by consulting the medical records and follow-up results(The maximum knee flexion angle that can be achieved without internal fixation failure during the operation.). The fracture healing, knee function recovery and postoperative complications were observed. Bostman score was used to evaluate knee joint function 3 and 9 months after operation. The biomechanical analysis of the finite element model showed that the maximum displacement of the Kirschner wire group was 1.77 times that of the ALP group at I-degree of the lower pole bone, the maximum stress of the Kirschner wire group was 1.21 times that of the ALP group, and the maximum stress of the Kirschner wire group was 13.29 times that of the ALP group. The maximum displacement of the II-degree of the lower pole bone in the Kirschner wire group was 2.22 times that of the ALP group, the maximum stress in the Kirschner wire group was 1.53 times that of the ALP group, and the maximum stress in the Kirschner wire group was 15.34 times that of the ALP group. The maximum displacement of the III-degree of the lower pole bone in the Kirschner wire group was 3.43 times that of the ALP group, the maximum stress in the Kirschner wire group was 1.60 times that of the ALP group, and the maximum stress in the Kirschner wire group was 16.86 times that of the ALP group. All avulsion fractures of the inferior patellar pole healed well without serious complications such as internal fixation failure or infection. The average operation time was 81.87 min ( 72-87 min ), the average final knee range of motion ( ROM ) was 124.50 ° ( 118 ° -130 ° ), the average Bostman score was 26.38 ( 24-29 ) in the third month, and the average Bostman score was 28.63 ( 27-30 ) in the ninth month. All patients showed good knee function one year after the operation. With the change of fracture line to the distal end, the biomechanical stability of anchor loop plate was less affected by the change of fracture line, while the influence of Kirschner wire tension band combined with patellar cerclage technology tended to be unstable. Therefore, for sleeve avulsion fracture of the inferior pole of the patella, anchor loop plate has more biomechanical stability. In the preliminary study of clinical cases, the internal fixation effect of ALP technique for the fixation of lower polar sleeve avulsion fracture of patella is good in the short-term observation. The stable mechanical properties can allow early knee joint function exercise, which may bring good knee joint function to patients with this type of fracture.