Objective To observe the effect of biological fixation of femoral stem prosthesis with multilayer macropores coating by combined use of autologousbone grafting. Methods The reconstructing femoral stem prostheses were designed personally, proximal 2/3 surfaces of which were reformed by thick multilayer stereo pore structure. Twentyfour adult mongrel canines underwent right femoralhead replacement and were divided randomly into two groups. The autogenous bonemud of femoral head and neck were not used in the control group. The histologicexamination, roentgenograms and biomechanical test were carried out in the 1st,3rd and 6th month after operation to observe the bone formation and fixation inthe exterior and interior sides of the prostheses. Results Onthe whole view,bone reconstruction occurred in experimental group in the 3rd and 6th month. Roentgenograms also proved to be superior to the control group. Histological examinationshowed that both the maximum bone inserting depth（μm） and average engorging ratio(%) of newly formed bone in experimental group surpassed those in the control group. The maximum shear strength of prosthesisbone interface in experimental group was significantly higher than that in the control group（Plt;0.01）. Conclusion Intensity of biological fixation can be strengthened remarkably by using femoral stem prothesis with multilayer macropores coating by combined use of autologous bone grafting.
ObjectiveTo estimate the outcome of cerclage followed by a figure-of-eight tension band with a single titanium wire for the treatment of patellar fracture.MethodsA retrospective analysis was made on the clinical data of 46 patients with patellar fractures treated between June 2012 and November 2014. There were 30 males and 16 females, aged 20-86 years (mean, 54 years). The fracture causes included falling in 27 cases, traffic accident in 16 cases, and knock in 3 cases. There were 41 cases of closed fractures and 5 cases of open fracture. The injury located at the left side in 24 cases and the right side in 22 cases. According to AO classification, fracture was rated as type 34-A in 3 cases, as type 34-B in 1 case, as type 34-C1 in 7 cases, as type 34-C2 in 13 cases, and as type 34-C3 in 22 cases. The time between injury and operation ranged 1-12 days (mean, 3.7 days). During operations, a single titanium wire was used to pass around the patellar, followed a figure-of-eight wrapping, to tight and fix at the tension of 35 kg.ResultsAll incisions healed primarily. The patients were followed up 20.6 months on average (range, 6-24 months). Partial wire loosening was found in 2 cases, irritation of skin or soft tissue in 1 case. The X-ray examination showed bony healing at 3 months after operation, without breakage of titanium wire. The internal fixation was removed in 38 cases at 12 months after operation. According to the Böstman rating score, the mean score was 28.34 (range, 24-30) at 12 months after ope-ration; the results were excellent in 42 cases and good in 4 cases, with an excellent and good rate of 100%.ConclusionFor patellar fracture, cerclage followed by a figure-of-eight tension band with a single titanium wire is able to achieve an effective stability and to allow early motion for patient with less complication.
Objective To investigate the effects of titanium modified by ultrasonic acid etching/anodic oxidation (UAT) loaded with endothelial progenitor cells-exosome (EPCs-exo) on proliferation and osteogenic and angiogenic differentiations of adipose-derived stem cells (ADSCs). Methods The adipose tissue and bone marrow of 10 Sprague Dawley rats were harvested. Then the ADSCs and EPCs were isolated and cultured by collagenase digestion method and density gradient centrifugation method, respectively, and identified by flow cytometry. Exo was extracted from the 3rd to 5th generation EPCs using extraction kit, and CD9 and CD81 were detected by Western blot for identification. The three-dimensional printed titanium was modified by ultrasonic acid etching and anodic oxidation to prepare the UAT. The surface characteristics of UAT before and after modification was observed by scanning electron microscopy; UAT was placed in EPCs-exo solutions of different concentrations (100, 200 ng/mL), and the in vitro absorption and release capacity of EPCs-exo was detected by BCA method. Then, UAT was placed in DMEM medium containing different concentrations of EPCs-exo (0, 100, 200 ng/mL), and co-cultured with the 3rd generation ADSCs to construct UAT-ADSCs-exo. Cell morphology by laser confocal microscopy, live/dead cell staining, and cell proliferation were observed to evaluate biocompatibility; alkaline phosphatase (ALP) staining and alizarin red staining, RT-PCR detection of osteogenesis-related genes [osteocalcin (OCN), RUNT-related transcription factor 2 (Runx2), ALP, collagen type 1 (COL-1)] and angiogenesis-related gene [vascular endothelial growth factor (VEGF)], immunofluorescence staining for osteogenesis (OCN)- and angiogenesis (VEGF)-related protein expression were detected to evaluate the effect on the osteogenic and angiogenic differentiation ability of ADSCs. Results Scanning electron microscopy showed that micro-nano multilevel composite structures were formed on the surface of UAT. About 77% EPCs-exo was absorbed by UAT within 48 hours, while EPCs-exo absorbed on the surface of UAT showed continuous and stable release within 8 days. The absorption and release amount of 200 ng/mL group were significantly higher than those of 100 ng/mL group (P<0.05). Biocompatibility test showed that the cells in all concentration groups grew well after culture, and the 200 ng/mL group was better than the other groups, with fully spread cells and abundant pseudopodia, and the cell count and cell activity were significantly higher than those in the other groups (P<0.05). Compared with the other groups, 200 ng/mL group showed enhanced ALP activity and mineralization ability, increased expressions of osteogenic and angiogenic genes (OCN, Runx2, COL-1, ALP, and VEGF), as well as increased expressions of OCN and VEGF proteins, with significant differences (P<0.05). Conclusion EPCs-exo can effectively promote the adhesion, proliferation, and osteogenic and angiogenic differentiation of ADSCs on UAT surface, the effect is the most significant when the concentration is 200 ng/mL.
Objective To compare the effectiveness between three-dimensional (3D) printed porous titanium alloy cage (3D Cage) and poly-ether-ether-ketone cage (PEEK Cage) in the posterior lumbar interbody fusion (PLIF). Methods A total of 66 patients who were scheduled to undergo PLIF between January 2018 and June 2019 were selected as the research subjects, and were divided into the trial group (implantation of 3D Cage, n=33) and the control group (implantation of PEEK Cage, n=33) according to the random number table method. Among them, 1 case in the trial group did not complete the follow-up exclusion study, and finally 32 cases in the trial group and 33 cases in the control group were included in the statistical analysis. There was no significant difference in gender, age, etiology, disease duration, surgical segment, and preoperative Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The operation time, intraoperative blood loss, complications, JOA score, intervertebral height loss, and interbody fusion were recorded and compared between the two groups. Results The operations of two groups were completed successfully. There was 1 case of dural rupture complicated with cerebrospinal fluid leakage during operation in the trial group, and no complication occurred in the other patients of the two groups. All incisions healed by first intention. There was no significant difference in operation time and intraoperative blood loss between groups (P>0.05). All patients were followed up 12-24 months (mean, 16.7 months). The JOA scores at 1 year after operation in both groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between groups (P>0.05) in the difference between pre- and post-operation and the improvement rate of JOA score at 1 year after operation. X-ray film reexamination showed that there was no screw loosening, screw rod fracture, Cage collapse, or immune rejection in the two groups during follow-up. At 3 months and 1 year after operation, the rate of intervertebral height loss was significantly lower in the trial group than in the control group (P<0.05). At 3 and 6 months after operation, the interbody fusion rating of trial group was significantly better in the trial group than in the control group (P<0.05); and at 1 year after operation, there was no significant difference between groups (P>0.05). ConclusionThere is no significant difference between 3D Cage and PEEK Cage in PLIF, in terms of operation time, intraoperative blood loss, complications, postoperative neurological recovery, and final intervertebral fusion. But the former can effectively reduce vertebral body subsidence and accelerate intervertebral fusion.
Objective To systematically review the effectiveness and safety of power chain vs. nickel titanium coil springs in closing dental extraction space. Methods Databases including PubMed, EMbase, The Cochrane Library, Chinese Biomedicine Literature Database, Chinese Scientific Journals Full-text Database, and Chinese Journal Full-text Database were searched to collect the randomized controlled trials (RCTs) on comparing power chain with nickel titanium coil springs published before February 2012. Two reviewers independently screened literature, extracted data and assessed the quality of the included studies. Then meta-analysis was conducted using RevMan 5.0 software. Results A total of 4 RCTs involving 122 patients were included. The results of meta-analyses showed that there was a significant difference in the rate of space closure between the two groups (MD=0.30 mm per month, 95%CI 0.17 to 0.44, Plt;0.000 1); The results of subgroup analyses indicated that, both high-quality trials (MD=0.20, 95%CI 0.07 to 0.34, P=0.003) and low quality trials (MD=0.40, 95%CI 0.30 to 0.50, Plt;0.000 01) showed no significant difference in the rate of space closure. Conclusion Current clinical evidence indicates nickel titanium coil spring is superior to power chain in the rate of space closure, but its long-term effect still needs to be proved by more large-scale RCTs.
Objective To analyze the effectiveness of single three-dimensional (3D)-printed microporous titanium prostheses and flap combined prostheses implantation in the treatment of large segmental infectious bone defects in limbs. MethodsA retrospective analysis was conducted on the clinical data of 76 patients with large segmental infectious bone defects in limbs who were treated between January 2019 and February 2024 and met the selection criteria. Among them, 51 were male and 25 were female, with an age of (47.7±9.4) years. Of the 76 patients, 51 had no soft tissue defects (single prostheses group), while 25 had associated soft tissue defects (flap combined group). The single prostheses group included 28 cases of tibial bone defects, 11 cases of femoral defects, 5 cases of humeral defects, 4 cases of radial bone defects, and 3 cases of metacarpal, or carpal bone defects, with bone defect length ranging from 3.5 to 28.0 cm. The flap combined group included 3 cases of extensive dorsum of foot soft tissue defects combined with large segmental metatarsal bone defects, 19 cases of lower leg soft tissue defects combined with large segmental tibial bone defects, and 3 cases of hand and forearm soft tissue defects combined with metacarpal, carpal, or radial bone defects, with bone defect length ranging from 3.8 to 32.0 cm and soft tissue defect areas ranging from 8 cm×5 cm to 33 cm×10 cm. In the first stage, vancomycin-loaded bone cement was used to control infection, and flap repair was performed in the flap combined group. In the second stage, 3D-printed microporous titanium prostheses were implanted. Postoperative assessments were performed to evaluate infection control and bone integration, and pain release was evaluated using the visual analogue scale (VAS) score. Results All patients were followed up postoperatively, with an average follow-up time of (35.2±13.4) months. In the 61 lower limb injury patients, the time of standing, walk with crutches, and fully bear weight were (2.2±0.6), (3.9±1.1), and (5.4±1.1) months, respectively. The VAS score at 1 year postoperatively was significantly lower than preoperative one (t=−10.678, P<0.001). At 1 year postoperatively, 69 patients (90.8%) showed no complication such as infection, fracture, prosthesis displacement, or breakage, and X-ray films indicated good integration at the prosthesis-bone interface. According to the Paley scoring system for the healing of infectious bone defects, the results were excellent in 37 cases, good in 29 cases, fair in 3 cases, and poor in 7 cases. In the single prostheses group, during the follow-up, there was 1 case each of femoral prostheses fracture, femoral infection, and tibial infection, with a treatment success rate of 94.1% (48/51). In lower limb injury patients, the time of fully bear weight was (5.0±1.0) months. In the flap combined group, during the follow-up, 1 case of tibial fixation prostheses screw fracture occurred, along with 2 cases of recurrent foot infection in diabetic patients and 1 case of tibial infection. The treatment success rate was 84.0% (21/25). The time of fully bear weight in lower limb injury patients was (5.8±1.2) months. The overall infection eradication rate for all patients was 93.4% (71/76). Conclusion The use of 3D-printed microporous titanium prostheses, either alone or in combination with flaps, for the treatment of large segmental infectious bone defects in the limbs results in good effectiveness with a low incidence of complications. It is a feasible strategy for the reconstruction of infectious bone defects.
The rutile structure titanium oxide (Ti-O) film was prepared on the pure titanium material TA2 (99.999%) surface by the magnetic filter high vacuum arc deposition sputtering source. The method can not only maintain the material mechanical properties, but also improve the surface properties for better biocompatibility to accommodate the physiological environment. The preparation process of the Ti-O film was as follows. Firstly, argon ions sputtered to the TA2 substrate surface to remove the excess impurities. Secondly, a metal ion source generated Ti ions and oxygen ions by the RF discharge. Meanwhile a certain negative bias was imposed on the sample. There a certain composition of Ti-O film was obtained under a certain pressure of oxygen in the vacuum chamber. Finally, X-ray diffraction was used to research the structure and composition of the film. The results showed that the Ti-O film of the rutile crystal structure was formed under the 0.18 Pa oxygen partial pressure. A Nano scratch experiment was used to test the coating adhesion property, which demonstrated that the film was stable and durable. The contact angle experiment and the platelet clotting experiment proved that the modified surface method had improved platelet adhesion performance, and, therefore, the material possessed better biocompatibility. On the whole, the evaluations proved the modified material had excellent performance.
ObjectiveTo compare the biomechanical characteristics of self-made nickel-titanium shape memory alloy stepped plate with calcaneal plate and cannulated compression screws in fixing calcaneal osteotomy.MethodsCalcaneal osteotomy was operated on 6 fresh-frozen lower limbs collected from donors. Then three kinds of fixation materials were applied in random, including the self-made nickel-titanium shape memory alloy stepped plate (group A), calcaneal plate (group B), and cannulated compression screws (group C). Immediately after fixation, axial loading of 20-600 N and 20 N/s in speed was introduced to record the biomechanical data including maximum displacement, elastic displacement, and maximum load. Then fatigue test was performed (5 Hz in frequency and repeat 3 000 times) and the same axial loading was introduced to collect the biomechanical data. Finally, the axial compression stiffness before and after fatigue test were calculated.ResultsThere was no significant difference in the axial compression stiffness between pre- and post-fatigue test in each group (P>0.05). However, the axial compression stiffness was significant higher in group A than that in groups B and C both before and after fatigue test (P<0.05). No significant difference was found between group B and group C (P>0.05).ConclusionSelf-made nickel-titanium shape memory alloy stepped plate is better than calcaneal plate and cannulated compression screws in axial load stiffness after being used to fix calcaneal osteotomy.
ObjectiveTo evaluate the effectiveness of three-dimensional (3D) printing artificial vertebral body and interbody fusion Cage in anterior cervical disectomy and fusion (ACCF) combined with anterior cervical corpectomy and fusion (ACDF).MethodsThe clinical data of 29 patients with multilevel cervical spondylotic myelopathy who underwent ACCF combined with ACDF between May 2018 and December 2019 were retrospectively analyzed. Among them, 13 patients were treated with 3D printing artificial vertebral body and 3D printing Cage as 3D printing group and 16 patients with ordinary titanium mesh Cage (TMC) and Cage as TMC group. There was no significant difference in gender, age, surgical segment, Nurick grade, disease duration, and preoperative Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score, and Cobb angle of fusion segment between the two groups (P>0.05). The operation time, intraoperative blood loss, hospitalization stay, complications, and implant fusion at last follow-up were recorded and compared between the two groups; JOA score was used to evaluate neurological function before operation, immediately after operation, at 6 months after operation, and at last follow-up; VAS score was used to evaluate upper limb and neck pain. Cobb angle of fusion segment was measured and the difference between the last follow-up and the immediate after operation was calculated. The height of the anterior border (HAB) and the height of the posterior border (HPB) were measured immediately after operation, at 6 months after operation, and at last follow-up, and the subsidence of implant was calculated.ResultsThe operation time of 3D printing group was significantly less than that of TMC group (t=3.336, P=0.002); there was no significant difference in hospitalization stay and intraoperative blood loss between the two groups (P>0.05). All patients were followed up 12-19 months (mean, 16 months). There was no obvious complication in both groups. There were significant differences in JOA score, VAS score, and Cobb angle at each time point between the two groups (P<0.05). There was an interaction between time and group in the JOA score (F=3.705, P=0.025). With time, the increase in JOA score was different between the 3D printing group and the TMC group, and the increase in the 3D printing group was greater. There was no interaction between time and group in the VAS score (F=3.038, P=0.065), and there was no significant difference in the score at each time point between the two groups (F=0.173, P=0.681). The time of the Cobb angle interacted with the group (F=15.581, P=0.000). With time, the Cobb angle of the 3D printing group and the TMC group changed differently. Among them, the 3D printing group increased more and the TMC group decreased more. At last follow-up, there was no significant difference in the improvement rate of JOA score between the two groups (t=0.681, P=0.502), but the Cobb angle difference of the 3D printing group was significantly smaller than that of the TMC group (t=5.754, P=0.000). At last follow-up, the implant fusion rate of the 3D printing group and TMC group were 92.3% (12/13) and 87.5% (14/16), respectively, and the difference was not significant (P=1.000). The incidence of implant settlement in the 3D printing group and TMC group at 6 months after operation was 15.4% (2/13) and 18.8% (3/16), respectively, and at last follow-up were 30.8% (4/13) and 56.3% (9/16), respectively, the differences were not significant (P=1.000; P=0.264). The difference of HAB and the difference of HPB in the 3D printing group at 6 months after operation and last follow-up were significantly lower than those in the TMC group (P<0.05).ConclusionFor patients with multilevel cervical spondylotic myelopathy undergoing ACCF combined with ACDF, compared with TMC and Cage, 3D printing artificial vertebrae body and 3D printing Cage have the advantages of shorter operation time, better reduction of height loss of fusion vertebral body, and maintenance of cervical physiological curvature, the early effectiveness is better.
Objective To evaluate the effectiveness of using titanium alloy trabecular bone three-dimensional (3D) printed artificial vertebral body in treating cervical ossification of the posterior longitudinal ligament (OPLL). Methods A retrospective analysis was conducted on clinical data from 45 patients with cervical OPLL admitted between September 2019 and August 2021 and meeting the selection criteria. All patients underwent anterior cervical corpectomy and decompression, interbody bone graft fusion, and titanium plate internal fixation. During operation, 21 patients in the study group received titanium alloy trabecular bone 3D printed artificial vertebral bodies, while 24 patients in the control group received titanium cages. There was no significant difference in baseline data such as gender, age, disease duration, affected segments, or preoperative pain visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), vertebral height, and C2-7 Cobb angle (P>0.05). Operation time, intraoperative blood loss, and occurrence of complications were recorded for both groups. Preoperatively and at 3 and 12 months postoperatively, the functionality and symptom relief were assessed using JOA scores, VAS scores, and NDI evaluations. The vertebral height and C2-7 Cobb angle were detected by imaging examinations and the implant subsidence and intervertebral fusion were observed. Results The operation time and incidence of complications were significantly lower in the study group than in the control group (P<0.05), while the difference in intraoperative blood loss between the two groups was not significant (P>0.05). All patients were followed up 12-18 months, with the follow-up time of (14.28±4.34) months in the study group and (15.23±3.54) months in the control group, showing no significant difference (t=0.809, P=0.423). The JOA score, VAS score, and NDI of the two groups improved after operation, and further improved at 12 months compared to 3 months, with significant differences (P<0.05). At each time point, the study group exhibited significantly higher JOA scores and improvement rate compared to the control group (P<0.05); but there was no significantly difference in VAS score and NDI between the two groups (P>0.05). Imaging re-examination showed that the vertebral height and C2-7 Cobb angle of the two groups significantly increased at 3 and 12 months after operation (P<0.05), and there was no significant difference between 3 and 12 months after operation (P>0.05). At each time point, the vertebral height and C2-7 Cobb angle of the study group were significantly higher than those of the control group (P<0.05), and the implant subsidence rate was significantly lower than that of the control group (P<0.05). However, there was no significant difference in intervertebral fusion rate between the two groups (P>0.05). Conclusion Compared to traditional titanium cages, the use of titanium alloy trabecular bone 3D-printed artificial vertebral bodies for treating cervical OPLL results in shorter operative time, fewer postoperative complications, and lower implant subsidence rates, making it superior in vertebral reconstruction.