ObjectiveTo study the surgical treatment method and effectiveness of Rüedi-Allg?wer Ⅲ type Pilon fractures. MethodsBetween May 2011 and April 2013,25 cases of Rüedi-Allg?wer Ⅲ type Pilon fracture (5 cases of open fractures and 20 cases of closed fractures) were treated.Of 25 cases,16 were male,and 9 were female,aged 24-45 years (mean,31 years).The left side was involved in 8 cases,and the right side in 17 cases.The disease causes were falling from height in 11 cases,traffic accident injury in 9 cases,and crash injury in 5 cases.The interval of injury and admission was 10-36 hours (mean,23.5 hours).The open reduction and internal fixation by posterolateral fibular incision and exposure of distal tibia and tibiotalar articular surface by anterior ankle incision were performed;the tibiotalar articular surface was reset and the tibia fracture end was fixed. ResultsHealing of incision by first intention was obtained in 15 cases,and healing by second intention in 6 cases undergoing skin grafting.Tension blister occurred in 4 patients,who achieved healing by second intention after treatment.All 25 patients were followed up 6-12 months (mean,8 months).During follow-up,no complication of ankle joint instability,traumatic arthritis,or loosening and breakage of internal fixation occurred.The X-ray films showed stable ankle joint,anatomic or near anatomic reduction of the tibiotalar articular surface,normal alignment of distal tibia,and good bony healing.At 6 to 12 months after operation,the flexion and extension of the ankle were normal,without pain of the ankle joint after removal of internal fixation.According to Mazur et al.rating system for ankle symptoms and function,the results were excellent in 5 cases,good in 12 cases,fair in 5 cases,and poor in 3 cases;the excellent and good rate was 68%. ConclusionThe procedure by anterior ankle lateral approach and posterolateral fibular approach can completely expose the tibiotalar articular surface,which is advantageous to displaced fracture reduction and fixation,and can achieve good effectiveness in treating Rüedi-Allg?wer Ⅲ type Pilon fractures.
ObjectiveTo analyze the effect of core stabilization exercise with unstable support surface on rehabilitation of patients with osteoporotic vertebral fracture.MethodsFrom January 2018 to January 2020, 66 patients with osteoporotic vertebral fractures in the Fifth Affiliated Hospital of Zhengzhou University were selected as the research objects. All patients were treated with percutaneous vertebroplasty. After operation, they were randomly divided into intervention group and control group by random number table method, with 33 cases in each group. Both groups were given routine rehabilitation intervention after operation, while the intervention group was given core stabilization exercise with unstable support surface at the same time. The vertebral height, shape, stability and gait of the two groups were compared 1 day before operation and 1 day after rehabilitation training.ResultsThere was no significant difference in gender, age, injured vertebral body, course of osteoporosis, years of education and marital status between the two groups (P>0.05). Before surgery, there was no statistically significant difference in the height ratio of the front edge of the injured vertebra, middle height ratio of the injured vertebra, back convex Cobb angle, track length when eyes were open, track length when eyes were closed, Romberg rate, track length per unit time when eyes were open, track length per unit time when eyes were closed, Romberg rate per unit time, deviation of the center of gravity on X-axis when eyes were open, deviation of the center of gravity on X-axis when eyes were closed, deviation of the center of gravity on Y-axis when eyes were open, deviation of the center of gravity on Y-axis when eyes were closed, stride length, step frequency or comfortable pace between the two groups (P>0.05). After training, the height ratio of the front edge of the injured vertebra [(79.26±12.15)% vs. (72.26±13.36)%], middle height ratio of the injured vertebra [(82.11±10.26)% vs. (75.64±9.56)%], back convex Cobb angle [(9.87±7.10) vs. (14.41±2.36)°], track length when eyes were closed [(1856.29±457.16) vs. (2358.48±786.45) mm], Romberg rate [(1.32±0.29)% vs. (1.87±0.54)%], track length per unit time when eyes were closed [(33.45±3.26) vs. (41.55±4.69) mm], Romberg rate per unit time [(1.41±0.30)% vs. (1.95±0.77)%], deviation of the center of gravity on X-axis when eyes were open [(11.06±1.36) vs. (16.54±2.22) mm], deviation of the center of gravity on X-axis when eyes were closed [(11.15±0.96) vs. (23.31±3.06) mm], deviation of the center of gravity on Y-axis when eyes were open [(12.57±1.84) vs. (15.56±2.06) mm], deviation of the center of gravity on Y-axis when eyes were closed [(15.69±2.05) vs. (18.96±3.56) mm], stride length [(0.57±0.12) vs. (0.49±0.10) m], step frequency [(1.09±0.29) vs. (0.94±0.20) step/s] and comfortable pace [(0.35±0.12) vs. (0.29±0.10) m/s] of the intervention group were better than those of the control group (P<0.05). There was no significant difference in the track length when eyes were open or track length per unit time when eyes were open between the two groups (P>0.05).ConclusionIn patients with osteoporotic vertebral body fractures, core stabilization exercise with unstable support surface on the basis of conventional rehabilitation interventions after surgery can effectively restore the height and shape of the vertebral body, and improve the stability and gait to a certain extent.
Objective To investigate the methods of establishing 3-dimensional skull model using electron beam CT(EBCT) data rapid prototyping technique, andto discuss its application in repairing crainomaxillofacial trauma. Methods The data were obtained by EBCTcontinuous volumetric scanning with 1.0 mm slice at thickness. The data were transferred to workstation for 3-dimensional surface reconstruction by computeraided design software and the images were saved as STL file. The data can be usedto control a laser rapid-prototyping device(AFS-320QZ) to construct geometricmodel. The material for the model construction is a kind of laser-sensitive resinpower, which will become a mass when scanned by laser beam .The design and simulation of operation can be done on the model. The image data were transferred to the device slice by slice. Thus a geometric model is constructed according to the image data by repeating this process. Preoperative analysis, surgery simulation and implant of bone defect could be done on this computer-aided manufacture d3D model. One case of craniomaxillofacial bone defect resulting from trauma wasreconstructed with this method. The EBCT scanning showed that the defect area was 4 cm×6 cm. The nose was flat and deviated to left. Results The -3dimensional -skull was reconstructed with EBCT data and rapid prototyping technique. The model can display the structure of 3-dimenstional anatomyand their relationship.The prefabricated implant by 3-dimensional model was well-matched with defect .The deformities of flat and deviated nose were corrected. The clinical result wassatisfactory after a follow-up of 17 months. Conclusion The 3-dimensional model of skull can replicate the prototype of disease and play an important role in the diagnosis and simulation of operation for repairing craniomaxillofacial trauma.
Superficial cartilage defect is an important factor that causes osteoarthritis. Therefore, it is very important to investigate the influence of superficial cartilage defects on its surface morphology and mechanical properties. In this study, the knee joint cartilage samples of adult pig were prepared, which were treated by enzymolysis with chymotrypsin and physical removal with electric friction pen, respectively. Normal cartilage and surface treated cartilage were divided into five groups: control group (normal cartilage group), chymotrypsin immersion group, chymotrypsin wiping group, removal 10% group with electric friction pen, and removal 20% group with electric friction pen. The surface morphology and structure of five groups of samples were characterized by laser spectrum confocal microscopy and environmental field scanning electron microscopy, and the mechanical properties of each group of samples were evaluated by tensile tests. The results show that the surface arithmetic mean height and fracture strength of the control group were the smallest, and the fracture strain was the largest. The surface arithmetic mean height and fracture strength of the removal 20% group with electric friction pen were the largest, and the fracture strain was the smallest. The surface arithmetic mean height, fracture strength and fracture strain values of the other three groups were all between the above two groups, but the surface arithmetic mean height and fracture strength of the removal 10% group with electric friction pen, the chymotrypsin wiping group and the chymotrypsin soaking group decreased successively, and the fracture strain increased successively. In addition, we carried out a study on the elastic modulus of different groups, and the results showed that the elastic modulus of the control group was the smallest, and the elastic modulus of the removal 20% group with electric friction pen was the largest. The above study revealed that the defect of the superficial area of cartilage changed its surface morphology and structure, and reduced its mechanical properties. The research results are of great significance for the prevention and repair of cartilage injury.
To review the structure and function of the calcified cartilage zone and its role in the pathogenesis of osteoarthritis (OA). Methods Recent l iterature about calcified zone was reviewed and analyzed in terms of architecture, composition, biomechanics, and biological function. Results Calcified zone has particular structure and material properties, and functions as a semi permeable membrane; chondrocytes in the calcified zone retain some characteristics of growth plate cells, which play a crucial role in cartilage function maintenance and pathogenesis of OA. Therefore, reconstructionof the calcified zone at osteochondral conjunction has become one of the hot research in the fields of interface tissue engineering. Conclusion It is necessary to pay more attention to calcified cartilage zone, which is important for both the treatment of OA and the preparation of tissue engineered osteochondral composite.
ObjectiveTo investigate the feasibility and effectiveness of motor imagery based brain computer interface with wrist passive movement in chronic stroke patients with wrist extension impairment.MethodsFifteen chronic stroke patients with a mean age of (47.60±14.66) years were recruited from March 2017 to June 2018. At baseline, motor imagery ability was assessed first. Then motor imagery based brain computer interface with wrist passive movement was given as an intervention. Both range of motion of paretic wrist and Barthel index was assessed before and after the intervention.ResultsAmong the 15 chronic stroke patients admitted in the study, 12 finished the whole therapy, and 3 failed to pass the initial assessment. After the therapy, the 12 participants who completed the whole sessions of the treatment and follow up had improved ability of control electroencephalogram, in whom 9 regained the ability to actively extend the affected wrist, and the other 3 failed to actively extend their wrist (the rate of active extending wrist was 75%). The activity of daily life of all the participants did not change significantly before and after intervention, and no discomfort was found after daily treatment.ConclusionIn chronic stroke patients with wrist extension impairment, motor imagery based brain computer interface with wrist passive movement training is feasible and effective.
Patients with amyotrophic lateral sclerosis ( ALS ) often have difficulty in expressing their intentions through language and behavior, which prevents them from communicating properly with the outside world and seriously affects their quality of life. The brain-computer interface (BCI) has received much attention as an aid for ALS patients to communicate with the outside world, but the heavy device causes inconvenience to patients in the application process. To improve the portability of the BCI system, this paper proposed a wearable P300-speller brain-computer interface system based on the augmented reality (MR-BCI). This system used Hololens2 augmented reality device to present the paradigm, an OpenBCI device to capture EEG signals, and Jetson Nano embedded computer to process the data. Meanwhile, to optimize the system’s performance for character recognition, this paper proposed a convolutional neural network classification method with low computational complexity applied to the embedded system for real-time classification. The results showed that compared with the P300-speller brain-computer interface system based on the computer screen (CS-BCI), MR-BCI induced an increase in the amplitude of the P300 component, an increase in accuracy of 1.7% and 1.4% in offline and online experiments, respectively, and an increase in the information transfer rate of 0.7 bit/min. The MR-BCI proposed in this paper achieves a wearable BCI system based on guaranteed system performance. It has a positive effect on the realization of the clinical application of BCI.
Regarding to the channel selection problem during the classification of electroencephalogram (EEG) signals, we proposed a novel method, Relief-SBS, in this paper. Firstly, the proposed method performed EEG channel selection by combining the principles of Relief and sequential backward selection (SBS) algorithms. And then correlation coefficient was used for classification of EEG signals. The selected channels that achieved optimal classification accuracy were considered as optimal channels. The data recorded from motor imagery task experiments were analyzed, and the results showed that the channels selected with our proposed method achieved excellent classification accuracy, and also outperformed other feature selection methods. In addition, the distribution of the optimal channels was proved to be consistent with the neurophysiological knowledge. This demonstrates the effectiveness of our method. It can be well concluded that our proposed method, Relief-SBS, provides a new way for channel selection.
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.
Objective To explore the influence of discectomy and artificial disc replacement on the upper lumbar facet joint and to provide the evidence for use of artificial disc replacement. Methods Under the loads of 200-2 000 N axis pressure and 1-10 Nm back-extending/side-bending pressure on the 7 fresh adult corpses, the pressure of L3,4facet joint was measured in the case of L4,5disc integrity, discectomy and artificial disc replacement and the statistical analysis was done.ResultsUnder the same load (axis, back-extending/side bending), there were significant differences (Plt;0.01) in the pressure of upper lumbar facet jointboth between disc integrity and discectomy and between discectomy and artificial disc replacement, and there was no difference(Pgt;0.05) between disc integrity and artificial disc replacement. Conclusion The stress ofupper lumbar facet joint reduced after discectomy, it implies that simply discectomy may change biomechanics of lumbar and lead to secondary lumbar structure degeneration. The stress of upper lumbar facet joint is close to the normal value after artificial disc replancement, it implies that artificial disc replacement may protect lumbar structure. It provides some biomechanics foundation and evidence for artificial disc replacement.