ObjectiveTo evaluate the stability of the fixation technique for the crossed rods consisting of occipital plate and C2 bilateral lamina screws by biomechanical test.MethodsSix fresh cervical specimens were harvested and established an atlantoaxial instability model. The models were fixed with parallel rods and crossed rods after occipital plate and C2 bilateral laminae screws were implanted. The specimens were tested in the following sequence: atlantoaxial instability model (unstable model group), under parallel rods fixation (parallel fixation group), and under crossed rods fixation (cross fixation group). The range of motion (ROM) of the C0-2 segments were measured in flexion-extension, left/right lateral bending, and left/right axial rotation. After the test, X-ray film was taken to observe the internal fixator position.ResultsThe biomechanical test results showed that the ROMs in flexion-extension, left/right lateral bending, and left/right axial rotation were significantly lower in the cross fixation group and the parallel fixation group than in the unstable model group (P<0.05). There was no significant difference between the cross fixation group and the parallel fixation group in flexion-extension and left/right lateral bending (P>0.05). In the left/right axial rotation, the ROMs of the cross fixation group were significantly lower than those of the parallel fixation group (P<0.05). After the test, the X-ray film showed the good internal fixator position.ConclusionThe axial rotational stability of occipitocervical fusion can be further improved by crossed rods fixation when the occipital plate and C2 bilateral lamina screws are used.
ObjectiveTo review the research progress of the biomechanics of proximal row carpal instability (IPRC).
MethodsThe related literature concerning IPRC was extensively reviewed. The biomechanical mechanism of the surrounding soft tissue in maintaining the stability of the proximal row carpal (PRC) was analyzed, and the methods to repair or reconstruct the stability and function of the PRC were summarized from two aspects including basic biomechanics and clinical biomechanics.
ResultsThe muscles and ligaments of the PRC are critical to its stability. Most scholars have reached a consensus about biomechanical mechanism of the PRC, but there are still controversial conclusions on the biomechanics mechanism of the surrounding soft tissue to stability of distal radioulnar joint when the triangular fibrocartilage complex are damaged and the biomechanics mechanism of the scapholunate ligament. At present, there is no unified standard about the methods to repair or reconstruct the stability and function of the PRC. So, it is difficult for clinical practice.
ConclusionSome strides have been made in the basic biomechanical study on muscle and ligament and clinical biomechanical study on the methods to repair or reconstruct the stability and function of PRC, but it will be needed to further study the morphology of carpal articular surface and the adjacent articular surface, the pressure of distal carpals to proximal carpal and so on.
ObjectiveTo summarize research progress on programmed death 1 (PD-1) and programmed death-ligand 1 (PD-L1) inhibitors and their combination therapies in colorectal cancer and to provide a new treatment direction for colorectal cancer.MethodThe relevant literatures on the application of the PD-1/PD-L1 inhibitors in the colorectal cancer in recent years were collected and reviewed.ResultsThe clinical trials of anti-PD-1/PD-L1 signaling pathway antibodies had made some achievements in the colorectal cancer, especially in the patients with high frequency microsatellite instability. And the combination therapy of multiple antibodies and the combination with chemotherapy and targeted therapies were more effective.ConclusionPD-1/PD-L1 inhibitors have some certain curative effects on survival of colorectal cancer with high frequency microsatellite instability, especially combination shows a better effect.
Objective To elucidate the new development, structural features and appl ication of the lumbar interspinous process non-fusion techniques. Methods With the review of the development course and important research works in the field of the lumbar inter-spinous process non-fusion techniques, the regularity summary, science induction, and prospect were carried out. Results The lumbar inter-spinous process non-fusion technique was a part of non-fusion insertof spinal division posterior surface. According to the design, it could be divided into two major categories: dynamic and static systems. The dynamic system included Coflex and device for intervertebral assisted motion; the static system included X-STOP, ExtenSure and Wall is. The lumbar inter-spinous process non-fusion technique was a new technique of spinal division, it could reserve the integrated function of intervertebral disc and zygapophysial joint, maintain or recover the segmental movement to a normal level, and have no adverse effect on the neighboring segments. A lot of basic and cl inical researches indicated that lumbar inter-spinous process insert had extensive appl ication to curatio retrogression lumbar spinal stenosis, discogenic low back pain, articular process syndrome, lumbar intervertebral disc protrusion and lumbar instabil ity and so on. Conclusion With the matures of lumbar inter-spinous process non-fusion techniques and the increased study of various types of internal fixation devices, it will greatly facil itate the development of treatment of lumbar degenerative disease. But long-term follow-up is needed to investigating the long-term efficacy and perfect operation indication.
Objective To observe the effectiveness of the combination of dynamic and static stabil ity in the treatment of old knee medial collateral l igament injury. Methods Between March 2004 and June 2008, 26 cases of old knee medial collateral l igament injury were treated, including 19 males and 7 females with a mean age of 38 years (range, 21-48 years). Injury was caused by traffic accident in 6 cases, by sprains in 12 cases, by fall ing from height in 8 cases. The location was left knee in 15 cases and right knee in 11 cases. Of them, 24 patients showed the positive result of knee valgus test, 2 cases showed sl ightly relaxed knee tendon. The knee X-ray films of valgus stress position showed that the medial joint space differences between both knees were 3-5 mm in 2 cases and 5-12 mm in 24 cases. The injuries included avulsion of the medial femoral condyle starting point in 19 cases, central laceration in 6 cases, and tibial point laceration concomitant meniscus injury in 1 case. The time from injury to hospital ization was 3-14 months (mean, 6.4 months). Gracil is muscle was used to repair knee medial collateral l igament and the sartorius muscle transfer to reconstruct the medial rotation of knee stabil ity function. Results All incisions healed by first intention. No joint infection, deep vein thrombosis, or other postoperative compl ications occurred. Twentysix cases were followed up 12-58 months with an average of 30 months. The results of knee valgus stress test were negative with no joint tenderness. At 3 months after operation, the knee X-ray films of valgus stress position showed the medial joint space differences between both knees were less than 1 mm. According to the modified Lysholm-Scale score, the results were excellent in 18 cases, good in 7 cases, and fair in 1 case with an excellent and good rate of 96% at last follow-up. Conclusion A combination of dynamic and static stabil ity in repairing old knee medial collateral l igament injury is easy-to-operate and has the advantages to perform the operation in the same incision, so it can avoid the shortcomings of single repair method and achieve better effectiveness.
Objective To explore the clinical effect of occipital-cervical fusion and its impact on cervical curvature, and preliminarily study the causes of postoperative dysphagia. Methods The data of 24 patients who underwent occipito-cervical fusion in the Fourth People’s Hospital of Zigong between January 2014 and December 2018 were retrospectively analyzed, including 13 males and 11 females, aged 33-82 years, with an average age of (58.3±13.3) years. Among them, there were 14 cases of atlas fractures, 6 cases of atlantoaxial fractures, 1 case of intraspinal canal space-occupying lesion, 2 cases of chronic atlantoaxial dislocation with spinal cord compression, and 1 case of instability caused by inflammatory diseases. Japanese Orthopedic Association (JOA) score and Visual Analogue Scale (VAS) score were used to evaluate neurological function and pain of patients preoperatively and postoperatively. Occipito-cervical angle (O-C2) and lower cervical angle (C2-C7) were measured to evaluate the preoperative and postoperative angle changes in patients. The causes of postoperative dysphagia were analyzed. Results All the 24 patients were followed up for 8-50 months (26.3 months on average). The mean JOA score increased from 11.6±1.5 before surgery to 15.4±1.2 at the last follow-up, and the mean VAS score decreased from 6.4±1.1 before surgery to 2.0±0.6 at the last follow-up; the differences between the two time points were statistically significant (P<0.001). The bone graft fusion rate was 95.8% (23/24). The mean O-C2 angle decreased from (16.5±7.6)° before surgery to (14.7±4.5)° at the last follow-up, with no statistical significance (P=0.395). The mean angle of C2-C7 increased from (9.4±5.5)° before surgery to (16.3±3.5)° at the last follow-up, and the difference was statistically significant (P<0.001). Two patients developed postoperative dysphagia, possibly due to fusion in a flexion position. Conclusion Occipito-cervical fusion has reliable efficacy in treating occipito-cervical instability, with a high fusion rate and a low incidence of complications, but it will change the physiological curvature of upper and lower cervical vertebra, and fusion in a flexion position may cause postoperative dysphagia.
The objective of the study is to analyze the biological characteristics and stability of the linear derivative Bac2a from bactenecin, compared with the control peptide melittin. The secondary structure, antibacterial activity, hemolytic activity, cell toxicity and stability of the Bac2a were determined by circular dichroism spectroscopy, broth micro-dilution method and MTT assay. The results showed that Bac2a was a nonregular curl in aqueous solution, however, it was an α-helix structure in the hydrophobic environment. The minimal inhibitory concentration (MIC) of Bac2a ranged from 2 to 32 μmol/L, so the bacteriostatic activity of Bac2a was strong. The hemolytic rate was only 14.81% when the concentration of Bac2a was 64 μmol/L, which showed that the hemolytic rate of Bac2a was low. The therapy index of Bac2a was 3.26, and the cytotoxicity was relatively low, thus the cell selectivity was relatively high. In addition, with the heating treatment of 100℃ for 1 h, Bac2a still possessed rather a high antibacterial activity and showed a good heating stability. In a word, Bac2a has good application prospects in food, medicine and other fields, and is expected as a substitute for traditional antibiotics.
Objective To investigate the method and the cl inical outcomes of reconstruction of the knee stability after resection of tumors of the proximal fibula. Methods The cl inical data were retrospectively analyzed, from 16 patients with tumors of the proximal fibula undergoing proximal fibular resections and reconstructions of the lateral collateral ligament and the tendon of the biceps femoris with anchors between January 2008 and December 2009 (test group). Five patients underwent proximal fibular resection but were not given reconstruction surgery at the same period as the control group. There was no significant difference in gender, ages, disease duration, and tumor site between 2 groups (P gt; 0.05). Lateral stress test was performed after operation; X-ray films were taken to measure the joint space. Musculoskeletal Tumor Society (MSTS) functional score system was used to evaluate the joint function. Results All incisions healed by first intention in 2 groups. Iatrogenic complete peroneal nerve function loss occurred in patients undergoing Malawer type II surgical resection. The patients in both groups were followed up 12 to 36 months, with an average of 30 months. One patient with osteosarcoma of the test group developed local recurrence, and died of lung and systemic metastases after 12 months; the other patients had no recurrence. At last follow-up, the results of knee lateral stress test were negative in the test group, and the joint space increased and was classified as grade A; the results of knee lateral stress test were positive in the control group, and the joint space was classified as grade D. The MSTS score was 97.5 ± 3.5 in the test group and 87.5 ± 3.5 in the control group, showing significant difference (t=2.85, P=0.01). Conclusion The reconstruction of the bony attachment of the lateral collateral ligament and the tendon of the biceps femoris with anchors after resection of the proximal fibula is a safe, rel iable, and simple technique to reconstruct knee stabil ity after resection of tumors of the proximal fibula.
Objective To investigate the cl inical results and complications of minimally invasive anterior transarticular screw fixation and fusion for atlantoaxial instabil ity. Methods Between May 2007 and December 2010, 13 patients with atlantoaxial instabil ity were treated with minimally invasive anterior transarticular screw fixation and fusion under endoscope. There were 11 males and 2 females, aged 17-61 years (mean, 41.3 years). The time between injury and operation was 5-14 days (mean, 7.4 days). All cases included 6 patients with Jefferson fracture, 5 with odontoid fracture, and 2 with os odontoideum. According to Frankel classification of nerve functions, 2 cases were rated as grade D and 11 cases as graed E. The operation time, intra-operative blood loss, radiation exposure time, and complications were recorded and analyzed. The stabil ity was observed by X-ray films. The cl inical outcome was assessed using the Frankel scale, and the fusion rates were determined by CT scan threedimensional reconstruction at last follow-up. Results The mean operation time was 124 minutes (range, 95-156 minutes); the mean intra-operative blood loss was 65 mL (range, 30-105 mL); and the mean radiation exposure time was 41 seconds (range, 30-64 seconds). Thirteen patients were followed up 12-47 months (mean, 25.9 months). No blood vessel and nerve injuries or internal fixator failure occurred. The bone fusion time was 6 months, and the dynamic cervical radiography showed no instabil ity occured. At last follow-up, the neurological function was grade E in all patients. The fusion rate was 84.6% (11/13). No continuous bone bridge was seen in the joint space of 2 patients, but they achieved stabil ity. Conclusion Minimally invasive anterior transarticular screw fixation and fusion is a safe and effective procedure for treatment of atlantoaxial instabil ity.
ObjectiveTo explore the effects of core stable training on cervical vertebrae pain, cervical function and balance ability in patients with neck type cervical spondylopathy (NTCS).MethodsFrom January to August 2018, 98 patients with NTCS were treated. According to the odd and even bed numbers, 49 patients were enrolled in the observation group and 49 were in the control group. The patients in the control group was given Kinesio tape treatment, and the observation group was given core stability training based on the treatment of the control group. Cervical vertebrae pain was assessed by Visual Analogue Scale (VAS), Clinical Assessment Scale for Cervical Spondylosis (CASCS) and Neck Disability Index (NDI); cervical vertebra activity were used to assess the cervical; the Berg Balance Scale (BBS) was used to assess patients’ balance before intervention and at the 4th week of intervention. The incidence of complications during the intervention and the effective of treatment 4 weeks after intervention were recorded. The recurrence rate 6 months after the intervention was recorded.ResultsThere were no significant difference in CASCS, NDI, VAS, and BBS scores between the two groups before intervention (P>0.05). At the 4th week of the intervention, the CASCS and BBS scores of the two groups were higher than those before the intervention, and the VAS and NDI scores were lower than those before the intervention (P<0.05); and the CASCS and BBS scores in observation group at the 4th week of the intervention were higher than that of control group, and VAS and NDI scores were lower than those of the control group (P<0.05). There was no significant difference in the activity of the cervical vertebrae before intervention in both of the two groups (P>0.05). At the 4th week of the intervention, the activity of the cervical vertebrae in all directions was bigger than that of before the intervention in both of the two groups (P<0.05), and that in observation group were bigger than that of the control group (P<0.05). The effective rate at the 4th week in the observation group (95.92%) was higher than that in the control group (81.83%)(P<0.05). The recurrence rate 6 months after intervention in the observation group (6.38%) was lower than that in the control group (22.50%) (P<0.05).ConclusionCore stability training can relieve cervical spondylosis in NTCS patients, and improve the cervical function and patients’ balance; it has high safety and stable efficacy.
