Objective: To analyze the mid-term clinical efficacy of extended to C1, 2 posterior single-door laminoplasty for the treatment of ossification of the posterior longitudinal ligament combined the upper cervical spine. Methods: From February 2013 to December 2015, 32 patients with cervical OPLL who were extended to C1, 2 posterior open-door laminoplasty were enrolled in our hospital (complete follow-up of 25 patients). There were 19 males and 6 females, aged 48-76 years (mean 60.1±7.0 years). Cervical spinal cord function was assessed using the Japanese Orthopaedic Association (JOA) spinal cord function score, and the rate of improvement in neurological function was calculated. The quality of life of patients was assessed using the neck disability index (NDI). Axial symptoms were assessed and indexed using the visual analog scale (VAS). The C0-2 angle of the cervical spine was measured by X-ray preoperative and at the last follow-up. The cervical curvature was evaluated by the C2-7 angle, and the cervical vertebra activity was observed by the dynamic X-ray of the cervical spine. Results: 25 patients were followed up for a period of 26-64 months (mean 35.9±8.1 months). At the last follow-up, the JOA score was 14.32±3.24, the NDI score was 7.61±1.23, and the VAS score was 1.42±0.78. The differences between the three scores were statistically significant compared with the preoperative scores. The neurological improvement rate at the last follow-up was 79.61%±13.23%. The preoperative C0-2 angle was 26.04°±6.28°, and the last follow-up was 24.92°±5.51°; the C2-7 angle was 19.55°±9.42° before surgery, and the C2-7 angle at last follow-up was 17.97°±8.80°. The C2-7 angle at last follow-up was slightly reduced compared with that preoperative, but the difference was not statistically significant. The preoperative cervical vertebra ROM was 35.31°±12.24°, and at the last follow-up it was 32.23°±9.65°. The ROM of cervical vertebrae at the last follow-up was slightly lower than that before surgery, but the difference was not statistically significant. Among them, the reduction of the ROM of overflexion was greater than that of the over-extension, which was the main reason for the decrease of ROM. The OPLL bone mass continued to grow at the last follow-up of 11 patients. Conclusion The extended to C1, 2 posterior single-door laminoplasty for the treatment of ossification of the posterior longitudinal ligament combined the upper cervical spine can achieve adequate spinal cord decompression, satisfactory neurological improvement, and improve the postoperative cervical curvature and activity. There was no obvious change in the curvature and activity of the cervical spine, and the axial symptoms did not increase significantly, and the clinical efficacy was positive.

Objective: To develop a new type of triple-leaf-enhanced cervical spine plate system, to study its biomechanical properties, perform clinical preliminary applications, and observe clinical effects. Methods: Twelve fresh goat specimens were used, and the high-precision digital display grating displacement sensor system was used to compare the stability, fatigue strength and tensile strength of the fixation of the anterior nailing of the new type of triple-leaf-enhanced cervical spine plate system. All of 92 patients with cervical spondylosis who underwent cervical anterior decompression, cage or titanium mesh fusion, with new PRUNUS spine plate system or Atlantis spine plate system internal fixation were selected from January 2015 to January 2018. Comparative study recorded intraoperative blood loss, operative time, preoperative cervical Cobb angle, pain visual analogue scale (VAS), and Japanese Orthopaedic Association (JOA) spinal function score, and neurological improvement ratewas calculated. Frankel grading was used to evaluate pre and postoperative functional status of the anterior and posterior nerves, so as to comprehensively evaluate the initial clinical efficacy of the new PRUNUS spine plate system. Results: The biomechanical tests showed that: 1) The flexion, extension, left bending, right bending, left rotation and right rotation ROM after fixing with the new PRUNUS spine plate system were 1.02°±0.13°, 1.32°±0.11°, 0.96°±0.23°, 1.03°±0.19°, 1.37°±0.17° and 1.05°±0.08°. ROM after fixation of Atlantis spine plate system were 0.99°±0.11°, 1.08°±0.23°, 0.83°±0.21°, 0.82°±0.13°, 1.18°±0.43°, 1.17°±0.17°, respectively. There was no significant statistical difference between the two groups; 2) The fatigue life of the new PRUNUS spine plate system and Atlantis spine plate system were 6.3×10⁵ and 6.1×10⁵, and the fatigue strengths were 512.12 Mpa and 502.85 Mpa respectively. There was no statistical difference between the two groups. 3) The maximum pull-out force of the new PRUNUS spine plate system was 483.62±39.14 N, and the maximum pull-out force of the Atlantis spine plate system was 396.55±22.79 N. The difference between the two groups was statistically significant. In the clinical application, the new PRUNUS spine plate system was used, the average operation time was 102.8±13.6 min, and the average blood loss was 56.8±14.1 ml. Using the Atlantis spine plate system, the average operation time was 132.8±15.7 min, and the average blood loss was 76.8±19.1 ml. The difference between the two groups was statistically significant; Using the new PRUNUS spine plate system, the VAS score was reduced from 5.42±1.17 before surgery to 1.58±0.44, the preoperative JOA score was 8.13±1.26, and the JOA score was 14.71±1.16 at the last follow-up. Using the Atlantis spine plate system, the VAS score was 6.94±1.06 before surgery. dropped to 1.75±0.35, the preoperative JOA score was 9.26±1.32, and the JOA score was 14.96±1.56 at the last follow-up. There was no significant difference between the two groups. Conclusion The new PRUNUS spine plate system has good biomechanical properties and has a good effect on the stability of the cervical vertebra, especially for the postoperative renovations and osteoporosis patients. The operation is simple and convenient, safe and effective, and worthy of clinical promotion.

0bjective: To explore the feasibility and clinical efficacy of cervical vertebral dome expansion laminoplasty.. Methods: Our hospital from February 2017 to 2018 Sep 16 cases with cervical spinal canal dome of cervical spinal stenosis angioplasty in treatment of cervical spinal cord due to the medical records of patients, including 14 males and 2 females; Aged 49- 76 years old, average age 57.3±1.7 years old. The course of disease was 7-48 months, with an average disease duration 17.75±1.90 months. Of the 16 patients, 5 had multi-segment cervical disc herniation and 11 had long segmental ossification of the posterior longitudinal ligament. All the 16 patients underwent cervical C_3-7 dome-type spinal canal enlargement; the position, stability and spinal cord compression of the internal fixation were evaluated according to the patient's imaging data (X-ray, CT and MRI). The neck and upper extremity pain was evaluated by visual analogue scale (VAS) before and after operation. The cervical spinal cord function was evaluated by the Japanese Orthopaedic Association (JOA) spinal cord function score, and the rate of improvement of neurological function was calculated. The Frankel grading was used to evaluate the neurological function of patients before and after surgery. Results: Cervical X-ray, CT and MRI were performed in all patients before and after surgery. Operation time 55-110 min, mean 65±12 min, bleeding 100-220 ml, mean 110±20 ml. The cross-sectional area of the spinal canal and the median sagittal diameter of the spinal canal were significantly increased compared with the preoperative. All patients were followed up for an average of 10.9±1.4 months (3-20 months). Imaging examination showed that 16 patients had no loosening and fracture after internal fixation, and no re-closure occurred. MRI T2WI images showed continuous recovery of cerebrospinal fluid signal in the spinal cord of C_3-7 range. The preoperative VAS score was 7.3±0.9 points, the average VAS score at the last follow-up was 1.6±0.4 points, the preoperative JOA score was 6.9±1.1 points, and the last follow-up JOA score was 13.4±1.3 points. The improvement rate was 87.23%±3.81%; Frankel grade D before surgery, and Frankel grade E after surgery. Conclusion Cervical spinal canal domed simple angioplasty operation, spinal canal full, satisfactory clinical efficacy, and can effectively reduce the incidence of related complications, it is a safe and feasible method for the treatment of cervical spinal stenosis.

Objective: To explore the relationship between the compression depth and compressive stress of the anterior and posterior cervical spinal cord in different sports positions. Methods: Specimens of ten intact fresh cervical spine (C₁-T₁) from adult cadaver were collected. In order to simulate cervical disc degeneration and abnormal ligamentum flavum, we placed two hemispherical steel balls into the anterior and posterior side of the cervical spinal cord through the bone window of the C_{4, 5}. The measurement was conducted in 10%, 20%, 30%, 40%, 50%, and 60% of the sagittal diameter for the compressive stress of the anterior and posterior cervical spinal cord under different compression depths of flexion, neutral, and posterior extension. Results: The anterior depth of a certain pressure with the posterior pressure depth was increasing in neutral position, the stress on the anterior of the cervical cord-meningeal complex (CCMC) had no significant change, while the stress on the posterior of the CCMC increased greatly with the increasing of the degree of canal occlusion. The stress on the posterior of the CCMC varied insignificantly between 10% and 20% depth of canal occlusion (P>0.05). However, there was remarkable significance among 30% and 60% (P<0.05). In extension or flexion position, the stress on the anterior of the CCMC had no significant change, while the stress on the posterior of the CCMC increased greatly with the increasing of the degree of canal occlusion. The stress on the posterior of the CCMC varied insignificantly between neighboring depths of canal occlusion from 10% (P>0.05). However, there was remarkable significance among 20% and 60% (P<0.05). The posterior depth of a certain pressure with the anterior pressure depth was increasing in neutral position. The stress on the anterior of the CCMC increased greatly with the increasing of the degree of canal occlusion. The stress on the anterior of the CCMC varied insignificantly between 10% and 20% depth of canal occlusion(P>0.05). However, there was remarkable significance among 30% and 60% (P<0.05). The stress on the posterior of the CCMC had no significant change. In extension or flexion position, the stress on the anterior of the CCMC increased greatly with the increasing of the degree of canal occlusion. The stress on the anterior of the CCMC varied insignificantly between neighboring depths of canal occlusion from 10% (P>0.05). However, there was remarkable significance among 20% and 60% (P<0.05). The stress on the posterior of the CCMC had no significant change. Compared with the neutral position, the anterior flexion position and the posterior extension position had different trends in the compressive stress in the anterior and posterior aspect of the cervical spinal cord. Conclusion The stress on the anterior and the posterior of the CCMC has a closely nonlinear relationship with the depth of canal occlusion. With the increase of the depth of canal occlusion, the stress is increasing, especially running over the 30% depress of canal occlusion under neutral position. However, the stress is increased, especially running over the 20% depress of canal occlusion under the flexion and extension position.

BACKGROUND:Intervertebral disc degeneration is clinically considered to be the main cause of low back pain,but due to the unclear pathogenesis of intervertebral disc degeneration,there is still a lack of effective means to delay the progression of the disease.Single-cell RNA sequencing technology can amplify and sequence mRNA at the single-cell level,reveal the gene expression intensity of a single cell,discover different cell subsets in tissues according to the heterogeneity of cells,study the pathogenesis of intervertebral disc degeneration at the molecular level,and provide a new theoretical basis for its early diagnosis and treatment. OBJECTIVE:To introduce the basic principles of single-cell RNA sequencing technology and review the research progress of single-cell RNA sequencing technology in intervertebral disc degeneration in recent years. METHODS:A computer was used to search PubMed,Web of Science,CNKI and WanFang databases for the literature published from 2012 to 2022.Key words were"single-cell RNA sequencing,intervertebral disc degeneration,sequencing Technology"in Chinese and English.Duplicate,poor-quality and irrelevant articles were excluded;a total of 70 articles were eventually included. RESULTS AND CONCLUSION:(1)We identified new cell subsets such as homeostatic chondrocytes,hypertrophy chondrocyte-like nucleus pulposus cells and fibrous nucleus pulposus cells,identified the marker genes and transcription factors of these cell subsets,and described the functions,differentiation paths and cell fate of these cell subsets during the development and progression of intervertebral disc degeneration,and proposed the concept of progenitor nucleus pulposus cells.A cell subpopulation with progenitor nucleus pulposus cells properties was identified and its effectiveness in treating intervertebral disc degeneration was verified in mice.(2)Fibro chondrocyte-like annulus fibrosus cells and annulus fibrosus stem cells with both cartilage and fiber properties were identified,and a new type of composite hydrogel was prepared by combining fibrous cartilage inducers silk fibroin and hyaluronic acid in vitro.Experiments in mice demonstrated that this hydrogel could repair both annulus fibrosus tissue and cartilage matrix,and was remarkably effective in the treatment of intervertebral disc degeneration.(3)Regulatory chondrocytes were found in endplate cartilage.Two distinct fates in the progression of intervertebral disc degeneration were analyzed and the differential genes in the two fates were identified.Intercellular communication analysis indicated that regulatory chondrocytes interact with endothelial cells to promote angiogenesis.(4)Immune cells such as macrophages,T cells,myeloid progenitor cells and neutrophils were identified in the degenerated intervertebral disc tissues,demonstrating the existence of immune response during intervertebral disc degeneration.It was found that apolipoprotein induced the polarization of macrophages M1 and M2 subtypes,and this polarization process affected the activity of progenitor nucleus pulposus cells by amplifying the inflammatory response through the MIF signaling pathway.

Objective:To investigate the feasibility and early clinical effect of lumbar lateral anterior interbody fusion in the treatment of degenerative lumbar scoliosis.Methods:Forty patients with degenerative lumbar scoliosis who underwent lumbar lateral anterior interbody fusion combined with posterior percutaneous pedicle screw and rod internal fixation from January 2018 to January 2020 were selected. There were 17 males and 23 females; The age was 65.4±7.2 years (range 51-84 years). All patients had obvious low back pain, of which 22 patients (55.0%) had lower limb pain, numbness or intermittent claudication. 16 patients (40.0%) had scoliosis and the main curve protruded to the right, and 24 patients (60.0%) had scoliosis and the main curve protruded to the left. The operation time and intraoperative bleeding were recorded. The main outcome measures were visual analogue scale (VAS), Oswestry disability index (ODI), the MOS item short from health survey (SF-36), deformity correction, bone graft fusion time and complications.Results:The left approach was used in 16 cases of scoliosis with the main curve protruding to the right; In 24 cases, the main curve of scoliosis protruded to the left, of which 6 cases showed osteophyte on the concave side (right side) of coronal CT and the right approach was adopted, while the rest were adopted the left approach. Single segment fusion was performed in 8 cases (20.0%), double segment fusion in 12 cases (30.0%), three segment fusion in 16 cases (40.0%), and four segment fusion in 4 cases (10%). Among the 22 patients with symptoms of lower limb nerve damage, 6 needed secondary unilateral laminectomy. All 40 patients completed the operation successfully, the operation time was 255±37 min (range 130-345 min) and the amount of intraoperative bleeding was 100±16.2 ml (range 10-505 ml). All patients were followed up for 12.8±4.5 months (range 6-24 months). The preoperative VAS score was 5.7±1.0, improved to 3.5±0.7 on the first day after operation, and 1.4±0.3 at the last follow-up. The difference was statistically significant ( F=2322.229, P <0.001). The preoperative ODI was 79.9%±9.3%, the first day after operation was 51.6%±8.9%, and the last follow-up was 11.7%±2.2%. The difference was statistically significant ( F=3770.411, P <0.001). SF-36 was 68.6±5.3 before operation and 78.4±5.5 on the first day after operation, which increased to 109.9 ± 4.9 at the last follow-up. The difference was statistically significant ( F=21736.486, P <0.001). The Cobb angle of lumbar scoliosis was 27.8°±14.1° before operation and 7.5°±3.5° on the first day after operation, the difference was statistically significant ( t=3.551, P <0.001); The height of intervertebral space was 10.9±2.1 mm before operation and 15.3±3.4 mm on the first day after operation, the difference was statistically significant ( t=2.106, P <0.001). 24 patients (60.0%) had pain or numbness in the front of the thigh, and 4 patients (10.0%) had quadriceps femoris weakness; These symptoms disappeared within 3 months after operation in 26 patients, except that the numbness in the front of the thigh was only reduced in 2 patients 3 months after operation. All patients achieved satisfactory fusion in all segments at the last follow-up, and there was no non-fusion. Conclusion:Lumbar lateral anterior interbody fusion is a safe and feasible method for the treatment of degenerative lumbar scoliosis.