Transforaminal endoscopic lumbar discectomy with two-segment foraminoplasty for the treatment of very highly migrated lumbar disc herniation: a retrospective analysis.

BACKGROUND: The surgical resection of very highly migrated lumbar disc herniation (VHM-LDH) is technically challenging owing to the absence of technical guidelines. Hence, in the present study, we introduced the transforaminal endoscopic lumbar discectomy (TELD) with two-segment foraminoplasty to manage VHM-LDH and evaluated its radiographic and midterm clinical outcomes. MATERIALS AND METHODS: The present study is a retrospective analysis of 33 consecutive patients with VHM-LDH who underwent TELD with two-segment foraminoplasty. The foraminoplasty was performed on two adjacent vertebrae on the basis of the migration direction of disc fragments to fully expose the disc fragments and completely decompress the impinged nerve root. The operation duration, blood loss, intra- and postoperative complications, and recurrences were recorded. Additionally, imageological observations were evaluated immediately after the procedure via magnetic resonance image and computerized tomography. Clinical outcomes were evaluated by calculating the visual analog scale (VAS) score and Oswestry Disability Index (ODI). The MacNab criterion was reviewed to assess the patients' opinions on treatment satisfaction. The resection rate of bony structures were quantitatively evaluated on postoperative image. The segmental stability was radiologically evaluated at least a year after the surgery. Additionally, surgery-related and postoperative complications were evaluated. RESULTS: The average age of the patients was 56.87 ± 7.77 years, with a mean follow-up of 20.95 ± 2.09 months. The pain was relieved in all patients immediately after the surgery. The VAS score and ODI decreased significantly at each postoperative follow-up compared with those observed before the surgery (P < 0.05). The mean operation duration, blood loss, and hospital stay were 56.17 ± 16.21 min, 10.57 ± 6.92 mL, and 3.12 ± 1.23 days, respectively. No residual disc fragments, iatrogenic pedicle fractures, and segmental instability were observed in the postoperative images. For both up- and down- migrated herniation in the upper lumbar region, the upper limit value of resection percentage for the cranial SAP, caudal SAP, and pedicle was 33%, 30%, and 34%, respectively; while those in the lower lumbar region was 42%, 36%, and 46%, respectively. At the last follow-up, the satisfaction rate of the patients regarding the surgery was 97%. Surgery-related complications including dural tear, nerve root injury, epidural hematoma, iatrogenic pedicle fractures, and segmental instability were not observed. One patient (3%) suffered from the recurrence of LDH 10 months after the initial surgery and underwent revision surgery. CONCLUSIONS: The TELD with two-segment foraminoplasty is safe and effective for VHM-LDH management. Proper patient selection and efficient endoscopic skills are required for applying this technique to obtain satisfactory outcomes.

Surgical management of lower limb radiculopathy following acute singe-level osteoporotic vertebral fracture of lower lumbar spine in geriatric patient: a retrospective study.

BACKGROUND: Radiculopathy of the lower limb after acute osteoporotic vertebral fractures (OVFs) in the lower lumbar spine is uncommon in geriatric patients. Moreover, surgical intervention is generally recommended in patients who are irresponsive to conservative treatment. Determining an optimum surgical strategy is challenging considering the poor general condition of this population. Thus, herein, we established an algorithm for surgically managing this clinical scenario, hoping to provide a reference for making a surgical decision. METHODS: We retrospectively studied patients who suffered from new-onset radiculopathy of the lower limb after acute single-level OVFs in the lower lumbar spine and eventually underwent surgical intervention at our department. Information on the demographics, bone quality, AO spine classification of the vertebral fracture, pre-existing degenerative changes, including foraminal stenosis and lumbar disc herniation, and surgical intervention type was collected. Additionally, clinical outcomes, including preoperative and postoperative visual analog scale (VAS) scores for back and leg pain, Oswestry disability index (ODI), and MacNab criterion for response to surgery, were evaluated. RESULTS: From September 2019 to December 2021, a total of 22 patients with a mean age of 68.59 ± 9.74 years were analyzed. The most involved vertebra was L5 (54.5%), followed by L4 (27.3%) and L3 (18.2%). Among the 22 patients, 15 (68.2%) were diagnosed with the A1 type fracture of AO classification, and among them, 11 (73.3%) were characterized by the collapse of the inferior end plate (IEP). Three patients (13.6%) suffered from A2-type fractures, whereas four patients (18.2%) suffered from A3-type fractures. Pre-existing degenerative changes were observed in 12 patients (54.5%) of the patients. A total of 16 patients (72.7%) were treated by percutaneous kyphoplasty (PKP). Additionally, three patients underwent posterior instrumentation and fusion, two patients underwent a secondary endoscopic foraminoplasty, and one patient underwent a secondary radiofrequency ablation. The mean follow-up period was 17.42 ± 9.62 months. The mean VAS scores for leg and back pain and ODI decreased significantly after the surgery (P < 0.05). The total satisfaction rate at the last follow-up was 90.9% per the Macnab criterion. CONCLUSION: Patients with OVFs in the IEP are predisposed to suffer from radiculopathy of the lower limb. PKP alone or in combination with other minimally invasive surgical strategies is safe and effective in treating stable fractures. Additionally, aggressive surgical intervention should be considered in patients with unstable fractures or severe foraminal encroachment.

Triangular Flap Insertion: An Option for Correction of Dog-Ears Deformity in High-Tension Areas.

Dog-ear deformity is a common protrusion defect of skin tissue after the closure of a surgical wound, affecting patients' appearance and quality of life. The common methods for correcting dog ears involve the removal of excess tissue in different directions or shapes after extending the incision along the long axis of the original wound. However, the literature regarding tissue preservation techniques for dog-ear correction is poor, especially for areas with insufficient skin tissue or high tension. The authors modified the original design of direct excisions, which transferred excess tissue from the horizontal axis of the wound to the longitudinal axis, thereby absorbing longitudinal tension and relieving linear scar contracture. This technique provides a way to correct dog ears without removing excess healthy tissue, especially as an option for dog-ear correction in high-tension areas.

Treatment for benign skin lesion in zygomatic-infraorbital region by the expanded multi-lobe cervicofacial advancement rotation flap in pediatric patients.

PURPOSE: Benign skin lesions in zygomatic-infraorbital regions severely influence pediatric patients' appearance as well as mental health. Treatments are difficult for the high requirements of patients' guardians in both function and aesthetics. The present study aims to introduce a surgical method, Expanded Multi-Lobe Cervicofacial Flap, which combines the advantages of the classical cervicofacial advancement rotation flap and the tissue expansion technique. METHODS: A total of 21 pediatric patients were enrolled. The treatment process included 2 stages: implantation of the skin tissue expander and flap transfer. The excessive skin created by tissue expansion extended the coverage area of the multi-lobe flap. RESULTS: In this retrospective study, follow-up periods were all more than 12 months (20.8 ± 6.7). In the last follow-ups, the flaps were all in good condition, and No facial organ displacement was observed. The patients' guardians were satisfied with the outcomes. CONCLUSIONS: Using the expanded multi-lobe cervicofacial flap for the zygomatic-infraorbital benign skin lesion repair is effective, and this method is especially applicable to the pediatric population.

Effect of long-term cervical extensor exercise program on functional disability, pain intensity, range of motion, cervical muscle mass, and cervical curvature in young adult population with chronic non-specific neck pain: a randomized controlled trial.

BACKGROUND: The prevalence of chronic non-specific neck pain (CNNP) is on the rise among the young adult population. We herein aimed to compare the effects of long-term specific cervical extensor training and stretching exercises on improving this chronic disorder in young adults. METHODS: In this prospective, randomized, controlled study, 70 participants aged 18-35 years with CNNP and cervical lordosis loss were included. The participants were assigned to undergo either specific cervical extensor training (observation group) or perform usual stretching exercises (control group). The exercise duration was set at 12 months, with 9 months at the clinic and 3 months at home. The outcome assessments included changes in the neck disability index, visual analog scale from baseline, cervical range of motion (CROM), cross-sectional areas (CSAs) of cervical extensors, and cervical curvature from baseline. The outcome measures were compared between groups at 3, 6, and 12 months of follow-up. RESULTS: All 70 participants underwent randomization, and no significant differences in demographics and baseline data were found between the two groups. The observation group showed a greater improvement in neck disability index and visual analog scale scores at the 12-month follow-up than the control group. Additionally, a more substantial increase in CROM and CSAs of cervical extensors was observed in the observation group at the 6-month and 12-month follow-ups (P < 0.05). Although more participants in the observation group achieved cervical lordosis at the 12-month follow-up, the difference was marginally nonsignificant (9% in the control group vs. 28% in the observation group, P = 0.075). CONCLUSIONS: In young adults with CNNP, long-term specific cervical extensor training was associated with a more significant clinically meaningful improvement in disability, pain, and CROM than stretching exercises. The increased CSAs of cervical extensors may potentially contribute to the restoration of cervical lordosis. Trial registration The study is registered at the Chinese domestic clinical trial (ChiCTR2000040009) at Chictr.org. The date of registration: November 18, 2020.

Reconstruction of Large Periorbital Defect With a Pre-expanded Retrograde Postauricular Island Flap: Our 13-Year Experiences.

The clinical application of the retrograde postauricular island flap has been widely restricted because of its limited size and high morbidity of venous congestion. Thus, in this article, we introduced a pre-expanded retrograde postauricular island flap to reconstruct the large periorbital defect. A total of 13 patients with periorbital lesions who had undergone the treatment of our flap were enrolled in the study. The whole series of operations was divided into 3 parts, including expander implantation in the postauricular region, a series of expander inflations, and flap transferring, and special incisions were also designed in the procedure. In the end, all the flaps survived without serious complications. The mean size of the harvested flaps was 2.65 times larger than that of our nonexpanded cases. The reconstructed periorbital region showed a functional and aesthetic repair outcome after a follow-up of 3 to 30 months. To conclude, the pre-expanded retrograde postauricular island flap was a safe way to reconstruct a larger periorbital defect.

A practical method for the retrieval of tulip-head polyaxial pedicle screw by reusing the rod in revision and implants removal surgery: introduction of technique and evaluation of clinical outcomes.

BACKGROUND: The removal of spinal implants is needed in revision surgery or in some cases whose fracture had healed or fusion had occurred. The slip of polyaxial screw or mismatch of instruments would make this simple procedure intractable. Here we introduce a simple and practical method to address this clinical dilemma. METHODS: This is a retrospective study. The patients underwent new technique for retrieving the implants from July 2019 to July 2022 were labeled as group A, while the patients underwent traditional implants retrieval technique from January 2017 to January 2020 were labeled as group B. Patients in each group were subdivided into revision surgery group (r group) and simple implants removal group (s group) according to the surgery fashion. For the new technique, the retrieved rod was cut off to a proper length which was matched with the size of tulip head, and was replaced into the tulip head. After tightened with nut, a monoaxial screw-rod "construct" was formed. Then the "construct" can be retrieved by a counter torque. The operation duration, intraoperative blood loss, post-operative bacteria culture, hospital stay and costs were analyzed. RESULTS: A total of 116 polyaxial screws with difficult retrieval (43 screws in group A, 73 screws in group B) in 78 patients were recorded, in which 115 screws were successfully retrieved. Significant differences were found in the mean operation duration, intraoperative blood loss when comparing the r group in group A and B, as well as the s group in group A and B (P < 0.05). There were no significant differences in hospital stay and costs between group A and B. Three patients were found positive bacteria culture of drainage tube/tape in group A (3/30), while 7 patients in group B (7/48). The most prevalent bacteria was Propionibacterium acnes. CONCLUSION: This technique is practical and safe in retrieving tulip head poly-axial screw. Reduced operation duration and intraoperative bloods loss may potentially alleviate the hospitalization burden of patients. Positive bacterial cultivation results are common after implants removal surgery, but they rarely represent an organized infection. A positive culture with P. acnes or S. epidermidis should be interpreted with caution.

Modified unilateral iliac screw fixation with partial reduction in the treatment of high-grade spondylolisthesis at L5/S1 in adult patients: introduction of key technique, report of clinical outcomes and analysis of spinopelvic parameters.

BACKGROUND: Management of high-grade spondylolisthesis (HGS) remains challenging. Spinopelvic fixation such as iliac screw (IS) was developed to deal with HGS. However concerns regarding constructs prominence and increased infection-related revision surgery have complicated it's use. We aim to introduce the modified iliac screw (IS) technique in treating high-grade L5/S1 spondylolisthesis and it's clinical and radiological outcomes. METHODS: Patients with L5/S1 HGS who underwent modified IS fixation were enrolled. Pre- and postsurgical upright full spine radiographs were obtained to analyze sagittal imbalance, spinopelvic parameters, pelvic incidence-lumbar lordosis mismatch (PI-LL), slip percentage, slip angle (SA), and lumbosacral angle (LSA). Visual analogue scale (VAS), Oswestry disability index (ODI) were evaluated pre- and postoperatively for clinical outcomes assessment. Estimated blood loss, operating time, perioperative complications and revision surgery were documented. RESULTS: From Jan 2018 to March 2020, 32 patients (15 males) with mean age of 58.66 ± 7.77 years were included. The mean follow-up period was 49 months. The mean operation duration was 171.67 ± 36.66 min. At the last follow-up: (1) the VAS and ODI score were significantly improved (p < 0.05), (2) PI increased by an average of 4.3°, the slip percent, SA and LSA were significantly improved (p < 0.05), (3) four patients (16.7%) with global sagittal imbalance recovered a good sagittal alignment, PI-LL within ± 10° was observed in all patients. One patient experienced wound infection. One patient underwent a revision surgery due to pseudoarthrosis at L5/S1. CONCLUSION: The modified IS technique is safe and effective in treating L5/S1 HGS. Sparing use of offset connector could reduce hardware prominence, leading to lower wound infection rate and less revision surgery. The long-term clinical affection of increased PI value is unknown.

Effects of tracer position on screw placement technique in robot-assisted posterior spine surgery: a case-control study.

INTRODUCTION: Robot-assisted spine surgery is increasingly used in clinical work, and the installation of tracers as a key step in robotic surgery has rarely been studied. OBJECTIVE: To explore the potential effects of tracers on surgical outcomes in robot-assisted posterior spine surgery. METHODS: We reviewed all patients who underwent robotic-assisted posterior spine surgery at Beijing Shijitan Hospital over a 2-year period from September 2020 to September 2022. Patients were divided into two groups based on the location of the tracer (iliac spine or vertebral spinous process) during robotic surgery and a case-control study was conducted to determine the potential impact of tracer location on the surgical procedure. Data analysis was performed using SPSS.25 statistical software (SPSS Inc., Chicago, Illinois). RESULTS: A total of 525 pedicle screws placed in 92 robot-assisted surgeries were analyzed. The rate of perfect screw positioning was 94.9% in all patients who underwent robot-assisted spine surgery (498/525). After grouping studies based on the location of tracers, we found there was no significant difference in age, sex, height and body weight between the two groups. The screw accuracy (p < 0.01)was significantly higher in the spinous process group compared to the iliac group (97.5% versus 92.6%), but the operation time (p = 0.09) was longer in comparison. CONCLUSION: Placing the tracer on the spinous process as opposed to the iliac spine may result in longer procedure duration or increased bleeding, but enhanced satisfaction of screw placement.

Comparison of clinical outcomes of modified laminoplasty with preservation of muscle group inserted into C2 and C7 spinous processes versus conventional C3-C7 laminoplasty: a prospective, randomized, controlled, noninferiority trial.

BACKGROUND: The efficacy and noninferior of performing modified double-door laminoplasty (MDDL) (C4-C6 laminoplasty plus C3 laminectomy, alongside a dome-like resection of the inferior part of the C2 lamina and the superior part of the C7 lamina) in patients with multilevel cervical spondylotic myelopathy (MCSM) is equivocal. A randomized, controlled trial is warranted. OBJECTIVE: The objective was to evaluate the clinical efficacy and noninferior of MDDL compared with traditional C3-C7 double-door laminoplasty. STUDY DESIGN: A single-blind, randomized, controlled trial. METHODS: A single-blind, randomized, controlled trial was conducted in which patients who with MCSM with greater than or equal to 3 levels of spinal cord compression from the C3 to the C7 vertebral levels were enrolled and assigned to undergo either MDDL group or conventional double-door laminoplasty (CDDL) group in a 1:1 ratio. The primary outcome was the change in the Japanese Orthopedic Association score from baseline to 2-year follow-up. The secondary outcomes included changes in the Neck Disability Index (NDI) score, the Visual Analog Scale (VAS) for neck pain, and imaging parameters. Operative complications were also collected and reported. The outcome measures were compared between the groups at 3 months, 1 year, or 2 years after surgery. RESULTS: A total of 96 patients (mean age 67 years, 39.8% women) underwent randomization. Of these patients, 93 completed 3-month follow-up, 79 completed 1-year follow-up, and 66 completed 2-year follow-up. The changes in the Japanese Orthopedic Association score did not differ significantly between the study groups at the three time points after surgery. With respect to amelioration of neck pain and disability related to neck pain, patients in the MDDL group had a significantly greater decrease in the VAS and NDI component summary score than did those in the CDDL group at 1-year (VAS: -2.5 vs. -3.2, difference -0.7, 95% CI -1.1 to -0.2, P =0.0035; NDI: -13.6 vs. -19.3, difference -5.7, 95% CI -10.3 to -1.1, P =0.0159) and 2-years (VAS: -2.1 vs. -2.9, difference -0.8, 95% CI -1.4 to -0.2, P =0.0109; NDI: -9.3 vs. -16.0, difference -6.7, 95% CI -11.9 to -1.5, P =0.0127). The changes in the range of motion (ROM), the C2-C7 Cobb angle, and the cervical sagittal vertical axis in the MDDL group were significantly less than those in the CDDL group (ROM: -9.2±6.4 vs. -5.0±6.0, P =0.0079; C2-C7 Cobb angle: -7.9±7.8 vs. -4.1±6.2, P =0.0345; cervical sagittal vertical axis: 0.6±0.9 vs. 0.2±0.6, P =0.0233). The MDDL group had less blood loss (428.1 vs. 349.1, P =0.0175) and a lower rate of axial symptoms (27.3 vs. 6.1%, P =0.0475) than the CDDL group. CONCLUSIONS: Among patients with MCSM, the MDDL produced similar cervical cord decompression compared with the conventional C3-C7 double-door laminoplasty. The modified laminoplasty was associated with meaningful improvement in amelioration of neck discomfort, maintaining a better cervical ROM and sagittal alignment, decreasing blood loss, and reducing the incidence of axial symptoms.

Influences of landscape pattern on water quality at multiple scales in an agricultural basin of western China.

Determining the associations between landscape pattern and river water quality and quantifying the abrupt change points of landscape metrics are vital to optimize landscape planning and improve basin water quality. This study took an agricultural basin in western China as a case study. River water quality of 61 sub-basin outlets were monitored during wet and dry seasons from 2020 to 2021. Landscape metrics were extracted at 100 m, 300 m, 500 m riparian buffer and sub-basin scales, respectively. Relationships between water quality and landscape pattern at multiple scales were explored by using redundancy analysis (RDA). Results showed that urban-related landscape metrics served as the primary contributor to degrade water quality during both seasons, followed by cropland-related metrics, which might be attributed to the increase of urban land and reduction of agricultural chemical fertilizer use. Landscape metrics could better explain the water quality variations during wet season than dry season. The explanatory abilities of landscape metrics to overall water quality appeared little difference among spatial scales during wet season, whereas landscape metrics within 100 m riparian buffer had much larger explanatory rate than other spatial scales during dry season. Results of abrupt change point analysis revealed that the abrupt change interval values (ACIVs) of percentage of urban land (PLANDurban) and the largest patch index of urban land (LPIurban) differed among COD, TN, and TP. The recommended threshold values of PLANDurban and LPIurban for COD, TN, and TP management were smaller than 11.0%, 2.5%, and 1.0%, respectively. When the PLANDurban or LPIurban exceeded 19.0%, the TN, TP, and COD pollution would all significantly accelerate. Therefore, a limit value of 19% of PLANDurban and LPIurban, respectively is put forward. From dry season to wet season, the ACIVs of PLANDurban and LPIurban for COD concentration increased, whereas they decreased for TN and TP concentrations. Our results can provide scientific insights into sustainable landscape planning and effective water quality protection in agricultural basins.

Conjugative Transfer of Acute Hepatopancreatic Necrosis Disease-Causing pVA1-Type Plasmid Is Mediated by a Novel Self-Encoded Type IV Secretion System.

The pathogenic pVA1-type plasmids that carry pirAB toxin genes are the genetic basis for Vibrio to cause acute hepatopancreatic necrosis disease (AHPND), a lethal shrimp disease posing an urgent threat to shrimp aquaculture. Emerging evidence also demonstrate the rapid spread of pVA1-type plasmids across Vibrio species. The pVA1-type plasmids have been predicted to encode a self-encoded type IV secretion system (T4SS). Here, phylogenetic analysis indicated that the T4SS is a novel member of Trb-type. We further confirmed that the T4SS was able to mediate the conjugation of pVA1-type plasmids. A trbE gene encoding an ATPase and a traG gene annotated as a type IV coupling protein (T4CP) were characterized as key components of the T4SS. Deleting either of these 2 genes abolished the conjugative transfer of a pVA1-type plasmid from AHPND-causing Vibrio parahaemolyticus to Vibrio campbellii, which was restored by complementation of the corresponding gene. Moreover, we found that bacterial density, temperature, and nutrient levels are factors that can regulate conjugation efficiency. In conclusion, we proved that the conjugation of pVA1-type plasmids across Vibrio spp. is mediated by a novel T4SS and regulated by environmental factors. IMPORTANCE AHPND is a global shrimp bacteriosis and was listed as a notifiable disease by the World Organization for Animal Health (WOAH) in 2016, causing losses of more than USD 7 billion each year. Several Vibrio species such as V. parahaemolyticus, V. harveyi, V. campbellii, and V. owensii harboring the virulence plasmid (designated as the pVA1-type plasmid) can cause AHPND. The increasing number of Vibrio species makes prevention and control more difficult, threatening the sustainable development of the aquaculture industry. In this study, we found that the horizontal transfer of pVA1-type plasmid is mediated by a novel type IV secretion system (T4SS). Our study explained the formation mechanism of pathogen diversity in AHPND. Moreover, bacterial density, temperature, and nutrient levels can regulate horizontal efficiency. We explore new ideas for controlling the spread of virulence plasmid and form the basis of management strategies leading to the prevention and control of AHPND.

Does the sagittal spinal profile differ between the elderly Chinese populations with and without lumbar disc herniation?

OBJECTIVE: To explore the characteristics of the sagittal spinopelvic profile in the elderly Chinese population with lumbar disc herniation (LDH) and to evaluate its influence on the severity, location and number of disc degeneration. METHODS: A retrospective analysis was conducted on 212 elderly Chinese patients with LDH and 213 asymptomatic volunteers with matched age and sex. Sagittal spinopelvic parameters were measured on the full-length X-ray and the sagittal profiles were determined according to the Roussouly classification. The severity, location and number of lumbar disc degeneration were evaluated from the L12 to L5S1 discs on the MRI images. RESULTS: There were no significant differences in BMI between the two groups. Patients with LDH were found to have significantly smaller TK, LL, and SS than those in the asymptomatic population (P < 0.05), while contradicting observations were obtained of PT and TPA (P < 0.05). In the LDH group, Roussouly type 1 and type 2 (50.4% and 28.7%, respectively) were predominant and the proportion of type 1 in the elderly LDH population was further increased compared to the younger LDH population. LDH population with Roussouly type 1 and 2 showed more caudal herniated locations and fewer herniated numbers than those with type 3 and 4. CONCLUSION: The sagittal spinopelvic profile was significantly different between the elderly Chinese population with and without LDH. There were significant differences in the Roussouly distribution between the elderly and the younger groups and different Roussouly types have different effects on the lumbar disc degeneration patterns.

Rosai-Dorfman disease with spine involvement: A case report.

RATIONALE: Rosai-Dorfman disease (RDD) is a rare, benign, self-limiting disease, also known as sinus histiocytosis with giant lymphadenopathy. Skeletal involvement is rare, and this isolated bone lesion usually occurs in adults with no other symptoms. It is estimated that 0.6% to 1% of RDD cases have isolated or complicated spinal lesions, which may occur in the bone, dura, and spinal parenchyma, but spinal RDD has no pathologic clinical or imaging features. PATIENT CONCERNS: A 25-year-old woman presented with complaints of low back pain without obvious causes for a month. DIAGNOSIS: RDD with spinal involvement. INTERVENTIONS: Resection of the spinous process of the third lumbar spine was performed under epidural anesthesia. OUTCOMES: At the time of discharge, the patient had no problems with autonomous activities and reported no discomfort. We also followed up the patient at 12 and 36 months after surgery, and the patient reported no discomfort, inconvenience, and no recurrence of symptoms. Imaging examination 1 year after surgery showed no recurrence. LESSON: This case suggests that surgery for RDD with spinal involvement may not require internal fixation.

Short-term posterior C1-C2 pedicle screw fixation without fusion to treat type II odontoid fracture among people under 60 years.

INTRODUCTION: Posterior C1-C2 pedicle screw fixation is a reliable technique used in treatment of type II odontoid fracture. However, the loss of cervical range of rotation motion (RORM) was inevitable. There were few studies focusing on the influence of short-term C1-C2 fixation with nonfusion technique to preserve cervical function in patients younger than 60 years. The purpose of this study was to compare cervical RORM which was measured by an improved goniometer, and the clinical outcomes between short-term and long-term C1-C2 fixation techniques in the treatment of Grauer type 2B and 2C odontoid fracture. MATERIALS AND METHODS: This study represents a retrospective analysis, including patients who underwent primary C1-C2 fixation surgery. These patients were divided into short-term and long-term groups based on whether underwent a fixation removal operation. The clinical results were collected and compared between the two groups. Independent T test and Chi-square analyses were used to identify significant differences between the two groups and dependent T test was used within each group. Statistical significance was set at p < .05. RESULTS: There were no severe postoperative complications, and all 60 patients achieved spinal stabilization after primary surgery. The mean rotation angle in the short-term group at last follow-up time was 138.39 ± 21.06°, which was better than 83.59 ± 13.06° in the long-term group (p < .05). The same statistical difference was observed in flexion-extension angle, which was 71.11 ± 18.73° in short-term group and 53.34 ± 18.23° in long-term group. The mean NDI score in short-term group at last follow-up time was 1.23 ± 0.86 and better than 8.24 ± 3.17 in long-term group. However, the VAS score in short-term group was 1.82 ± 0.54 which was worse compared to 0.64 ± 0.29 in long-term group. CONCLUSIONS: The results demonstrated that primary C1-C2 fixation with nonfusion technique could support satisfactory clinical effects. In addition, the removal of instruments after bony fusion could improve the function of cervical movement significantly in patients under 60 years.

The retropharyngeal steroid use during operation on the fusion rate and dysphagia after ACDF? A systematic review and meta-analysis.

PURPOSE: The aim of this meta-analysis was to investigate the effects of retropharyngeal steroid use during operation on bony fusion and dysphagia rate after ACDF. METHODS: We searched the electronic literature database of PubMed, Embase and the Cochrane Library published from January 1990 to February 2020. The size of each group, mean age, proportion of female patients, dysphagia events and fusion rate at one-year follow-up were extracted. RevMan 5.3 was used for the meta-analysis. RESULTS: A total of eight studies including six RCTs and two case-control studies met the inclusion criteria. This meta-analysis showed that retropharyngeal steroids could achieve significantly lower dysphagia rates (p < 0.001), higher fusion rates (p = 0.01), less moderate and severe events rates according to the Bazaz stratification (p < 0.001). However, there was no significant difference between two groups regarding operation time (p = 0.67), blood loss (p = 0.33), VAS scores at one day (p = 0.90) and VAS scores at two weeks (p = 0.80). CONCLUSIONS: Retropharyngeal steroid use is an effective method in reducing dysphagia rate, severe dysphagia rate and increasing fusion rate during ACDF surgery, without increasing operating time, blood loss or VAS scores at one day and two weeks. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Characteristics of the sagittal spinal balance in the asymptomatic elderly Chinese population.

PURPOSE: To investigate the normal values of the sagittal spinal parameters and analyze the distribution of the global spinal profiles in a Chinese population with age over 75. METHODS: Two hundred and twelve sets of the whole spine lateral radiographs were obtained from a database of an asymptomatic elderly population. Global and regional spinal parameters were measured. Sagittal profiles were determined according to the Roussouly classification compared with previous studies involving different populations. RESULTS: A total of 102 elderly subjects (≥ 75 years) were enrolled with an average age of 79.24 ± 3.53 years. The mean values of the spinopelvic parameters were 42.89 ± 11.64° for TK, 13.84 ± 10.78° for TLK, 44.48 ± 12.88° for LL, 44.76 ± 9.84° for PI, 17.19 ± 8.08° for PT, 28.35 ± 7.94° for SS, 3.47 ± 3.56 cm for SVA, 14.75 ± 7.85° for TPA, -0.27 ± 11.95° for PI-LL, respectively. Subjects ≥ 75 years were found to have significantly smaller LL and SS, but greater TLK, PT, SVA, TPA, and PI-LL than those 60-74 years (p < 0.05). Significant age- and sex-dependent differences were found in the Roussouly classification's distribution between the two subgroups. CONCLUSIONS: The normal values of the sagittal parameters were presented in the elderly Chinese asymptomatic population (≥ 75 years). Ethnic, age, and sex displayed significant effects on the behaviors of the sagittal spinal balance and profiles. These results could be served as physiological references for the planning of surgical strategies in elderly Chinese patients over 75 years.

Occipitocervical Revision Surgery Using the Bicortical Screw and Plate System for Failed Craniovertebral Junction Stabilization.

BACKGROUND: To evaluate the clinical efficacy and safety of the modified technique utilizing the occipital bicortical screws and plate system in occipitocervical revision surgery. METHODS: Between October 2010 and May 2018, 12 consecutive patients were retrospectively evaluated. All patients had posterior occipitocervical resurgery utilizing modified technique of bicortical screws and occipital plate. The measurements of extracranial occiput on midline were conducted on computed tomography (CT) scans. The thickness of the occipital bone at the location of external occipital protuberance and below 15 mm were evaluated, respectively. For the procedure, the trajectory was drilled perpendicular to the external occipital protuberance for the specified depth with a depth-limited drilling, 2 mm away from the internal bone plate, then the trajectory was deepened at intervals of 1 mm each time until reaching the internal bone plate. Meanwhile, a probe was used to explore all the walls of the trajectory. Bicortical screws were inserted to the occipital plate and the depth of penetration was less than 2 mm from the internal bone plate. Clinical efficacy and radiographic evaluation were followed up. RESULTS: The thickest point was the external occipital protuberance, which was 15.49 ± 1.47 mm and decreased gradually on the midline to 13.41 ± 1.60 mm at below 15 mm. Twelve cases (mean age 41.17 years; range, 24-62 years), including five males and seven females, were followed up for 24.08 months (14-32 months). The interval time was 40.42 months (3-156 months) after the initial operation. At the final follow-up, JOA score increased from 8.58 ± 2.53 before surgery to 12.67 ± 1.84 (P < 0.05) and VAS score improved from 6.17 ± 1.21 to 2.08 ± 1.32 (P < 0.05). Besides, clinical symptoms were relieved in all patients after revision surgery. All patients had rigid internal fixations with bone fusion and no major complications occurred. CONCLUSIONS: Posterior occipitocervical plate-screw system with bicortical screws had the advantages of safety, simple and promising efficacy without excessive tissue release or intraspinal manipulation, proving that it's valuable as a modified technique for occipitocervical revision surgery.

A Novel Bunyavirus Discovered in Oriental Shrimp (Penaeus chinensis).

Herein, we describe a novel bunyavirus, oriental wenrivirus 1 (OWV1), discovered in moribund oriental shrimp (Penaeus chinensis) collected from a farm in China in 2016. Like most bunyaviruses, OWV1 particles were enveloped, spherical- to ovoid-shaped, and 80-115 nm in diameter. However, its genome was found to comprise four segments of (-)ssRNA. These included an L RNA segment (6,317 nt) encoding an RNA-directed RNA polymerase (RdRp) of 2,052 aa, an M RNA segment (2,978 nt) encoding a glycoprotein precursor (GPC) of 922 aa, an S1 RNA segment (1,164 nt) encoding a nucleocapsid (N) protein of 243 aa, and an S2 RNA segment (1,382 nt) encoding a putative non-structural (NSs2) protein of 401 aa. All the four OWV1 RNA segments have complementary terminal decanucleotides (5'-ACACAAAGAC and 3'-UGUGUUUCUG) identical to the genomic RNA segments of uukuviruses and similar to those of phleboviruses and tenuiviruses in the Phenuiviridae. Phylogenetic analyses revealed that the RdRp, GPC, and N proteins of OWV1 were closely related to Wenzhou shrimp virus 1 (WzSV-1) and Mourilyan virus (MoV) that infect black tiger shrimp (P. monodon). Phylogenetic analyses also suggested that OWV1 could be classified into a second, yet to be established, species of the Wenrivirus genus in the Phenuiviridae. These wenriviruses also clustered with Wenling crustacean virus 7 from shrimps and bunya-like brown spot virus from white-clawed crayfish. Of note there were no homologs of the NSs2 of OWV1 and MoV/WzSV-1 in GenBank, and whether other crustacean phenuiviruses also possess a similar S2 RNA segment warrants further investigation. In addition, we established a TaqMan probe-based reverse-transcription quantitative PCR method for detection of OWV1, and it was detected as 1.17 × 102-1.90 × 107 copies/ng-RNA in gills of 23 out of 32 P. chinensis samples without an obvious gross sign. However, the discovery of OWV1 highlights the expanding genomic diversity of bunyaviruses.

The ratio of the posterior atlanto-occipital interval (PAOI): a novel radiographic ratio method evaluating the risk of cervical spondylotic myelopathy-a case-control study.

BACKGROUND: Our study aims to introduce a dynamic interval ratio method calculated using cervical hyperextension-flexion X-ray films. Secondarily, we aim to evaluate the relationship between the posterior atlanto-occipital interval ratio and cervical spondylotic myelopathy and explain the rationale. METHODS: We reviewed 83 cases with visible cervical dynamic X-ray films in our hospital from February 2015 to December 2018. Cases were divided into 2 groups according to their diagnosis (with or without spondylotic myelopathy). Radiographic measurements included the shortest distance between the posterior arch of the atlas and the occipital bone and cervical range of motion, and demographic data such as gender, age, and body mass index were also extracted. The posterior atlanto-occipital interval ratio (distance at hyperextension position/distance at hyperflexion position) was determined using logistic regression analysis models between the 2 groups. RESULTS: We included 40 cases in the disease group and 43 cases in the control group. The mean posterior atlanto-occipital interval ratio was 0.65±0.30 (mean ± standard deviation) in the disease group and 0.30±0.28 in the control group, with a significant difference (P<0.01). There was no correlation between the posterior atlanto-occipital interval ratio and gender or body mass index. However, the interval ratio had strong correlations with age, cervical spondylotic myelopathy, and Japanese Orthopaedic Association scores. Age, posterior atlanto-occipital interval ratio, and interval distance at hyperextension in the disease group were higher than those of the control group. Contrastingly, range of motion, Japanese Orthopaedic Association scores, and interval distance at the disease group's hyperflexion position were lower than in the control group. In all cases, the risk of cervical spondylotic myelopathy in the T2 group (cases with middle posterior atlanto-occipital interval ratio, according to the tertiles) was 6 times more than the T1 group (cases with lower ratio), and the T3 group (cases with higher ratio) had a 26.4 times greater risk than the T1 group. CONCLUSIONS: Our results suggest that the posterior atlanto-occipital interval ratio is a simple and meaningful parameter that could provide prognostic value for the risk of cervical spondylotic myelopathy through the imaging examinations of the selected cases. Higher posterior atlanto-occipital interval ratios indicate a greater risk for cervical spondylotic myelopathy and cervical musculoskeletal dysfunction. A higher posterior atlanto-occipital interval ratio may manifest undetected posterior atlanto-occipital stiffness, which needs more pathological evidence in future studies.