Explore the vast range of titles available.

The necessity of routinely placing closed suction wound drainage in spinal surgery has been questioned. This study aims to assess if closed suction wound drainage is necessary for posterior atlantoaxial fixation via intermuscular approach. The functional outcomes of these 40 patients who underwent posterior atlantoaxial fixation via intermuscular approach without drainage tube (Group A) were compared with that of a control group, which consisted of 68 randomly enrolled cases with posterior atlantoaxial fixation via intermuscular approach with drainage tube (Group B). Outcome assessments included American Spinal Injury Association (ASIA) scoring grade and Visual Analog Scale Score for Neck Pain (VASSNP). The postoperative analgesic consumption, the incidence of subcutaneous and surrounding ecchymosis and the time of ambulation were compared between two groups. Bone fusion was evaluated through computed tomography (CT) reconstruction. Postoperative paravertebral tissue edema was evaluated by the edema coefficient. The use of drainage tube had no significant influence on the postoperative analgesic consumption, wound ecchymosis, the time of ambulation and paravertebral tissue edema ( P  > 0.05). There were no statistically significant differences in the VASSNP and bone fusion rates during the follow-up period between the two groups ( P  > 0.05). All patients achieved ASIA grade E 3 months after surgery. No complications such as wound infection occurred in either group. Posterior atlantoaxial fixation via intermuscular approach does not necessitate postoperative drainage tube placement if there is no accidental vascular injury or excessive muscle bleeding occurs intraoperatively.

BACKGROUND:Sectioning of the C2 nerve root allows for direct visualization of the C1-2 joint and may facilitate arthrodesis. OBJECTIVE:To determine the clinical and functional consequences of C2 nerve root sectioning during placement of C1 lateral mass screws. METHODS:All patients undergoing C1 lateral mass screw fixation were included in this prospective study. A standard questionnaire was used to determine the severity of occipital numbness/pain and its effect on quality of life (QOL). Domains of the neck disability index were used to assess the disability related to C2 symptoms. RESULTS:A total of 28 patients were included (C2 transection, 8; C2 preservation, 20). A trend of decreased blood loss and length of surgery was observed in the C2 transection cohort. Occipital numbness was reported by 4 (50.0%) patients after C2 transection. Occipital neuralgia was reported by 7 (35.0%) patients with C2 preservation. None of the patients with numbness after C2 transection reported being “bothered” by it. All patients with occipital neuralgia after C2 sparing reported being “bothered” by it, and 57.1% reported a moderate to severe effect on QOL. The use of medication was reported by 5 (71.4%) patients with neuralgia vs none with numbness. Mean disability was significantly higher with neuralgia vs numbness (P = .016). CONCLUSION:C2 nerve root transection is associated with increased occipital numbness but this has no effect on patient-reported outcomes and QOL. C2 nerve root preservation can be associated with occipital neuralgia, which has a negative impact on patient disability and QOL. C2 nerve root transection has no negative consequences during C1-2 stabilization. ABBREVIATIONS:NDI, neck disability indexQOL, quality of life

Objective To observe the effects of occipitoaxial angle (O‐C2 angle, OC2A) and posterior occipitocervical angle (POCA) selection on postoperative clinical efficacy and lower cervical curvature in patients with acute acquired atlantoaxial dislocation after occipitocervical fusion (OCF). Methods A total of 150 healthy subjects without cervical disease (healthy group) were randomly selected based on gender and age. Three spine surgeons measured the OC2A and POCA of the healthy group and averaged the values. A total of 30 patients with an average age of 51.0 years (range, 18–70 years; 16 male and 14 female) with trauma or rheumatoid arthritis (disease group) who underwent occipitocervical fusion (OCF) for atlantoaxial dislocation between January 2012 and June 2016 were reviewed. OC2A, POCA, and cervical spinal angle (CSA) were measured postoperative/soon after surgery and ambulation, and at the final follow‐up visit. The preoperative and final follow‐up visual analog scale (VAS), Japanese orthopedics association score (JOA), neck disability index (NDI), and dCSA (change of CSA from postoperative/soon after surgery and ambulation to final follow‐up) were recorded. Results The values of OC2A and POCA in 150 healthy subjects were 14.5° ± 3.7° and 108.2° ± 8.1°, respectively, and the 95% confidence interval (CI) were 7.2°–21.8° and 92.3°–124.0°, respectively. There was a negative correlation between OC2A and POCA (r = −0.386, P < 0.001). There were 18 patients (group one) of ideal OC2A and POCA (both within 95% CI of the healthy group) postoperative/soon after surgery and ambulation with a mean follow‐up time of 26.3 ± 20.9 months in disease group. The remaining patients (group two) with a mean follow‐up time of 31.3 ± 21.3 months. There was no statistically significant difference in the baseline data as well as pre‐operative outcomes, including VAS score, JOA score, and NDI between the two groups. Likewise, the post‐operative outcomes in final follow‐up, including VAS and JOA score, had no distinct difference in the two groups. However, NDI (11.0 ± 2.9) in group two at the final follow‐up was significantly higher than that in group one (7.0 ± 2.3) (P < 0.001). And group two showed statistically greater dCSA (5.9 ± 7.5°) than group one (−2.3° ± 6.2°) (P = 0.003). Conclusions The negative correlation between OC2A and POCA plays an important role in maintaining the biodynamic balance of the occipital‐cervical region. OC2A and POCA should be controlled of a normal population in patients with acute acquired atlantoaxial dislocation during OCF, which can further improve the clinical efficacy and prevent loss of lower cervical curvature after surgery.

Background C1 posterior arch screw placement is one of the most effective treatments for atlantoaxial instability (AAI), which can be performed by either pedicle or lateral mass screw fixation. This study attempted to compare the feasibility and clinical outcomes of C1 pedicle with lateral mass screw fixations for treatment of AAI with C1 posterior arches >4 mm. Methods A total of 140 patients with AAI (C1 posterior arches measuring >4 mm) was enrolled in this single-center, randomized, double-blind trial. The subjects were randomly assigned into two treatments: C1 pedicle (group A) or lateral mass (group B) screw fixation. The patients, independent evaluating physicians and radiologists were blinded throughout the entire study. Patients were assessed before operation and in a series of follow-ups at 6 weeks, 6 months, 1 year, and 3 years post-surgery. The operation time, volume of blood loss, intraoperative complications, bone fusion rates, Japanese Orthopaedic Association (JOA) and visual analog scale (VAS) scores were monitored. Results All 140 patients showed overall improvements in clinical symptoms after surgery. The mean follow-up time was 24.5 ± 13.0 months. In both groups, the mean JOA scores improved significantly at the time of final follow-up as compared to prior surgery (group A: 7.1 ± 1.4 vs 13.7 ± 1.9; group B:7.3 ± 1.8 vs 13.1 ± 1.4; improvement rates: 87.2 % (group A) and 86.5 % (group B)). The VAS scores also decreased significantly in both groups at the time of final follow-up as compared to prior surgery (group A: 6.0 ± 1.3 vs 1.7 ± 0.8, and group B: 5.7 ± 1.1 vs 2.1 ± 1.2). Bone fusion was achieved within 12 months postoperatively in the patients from both groups. The operation time was significantly shorter and volume of blood loss was significantly less in the patients from group A as compared to group B ( p  < 0.01). Furthermore, thirteen patients had burst bleeding from the C1-2 venous plexus and nine patients had immediate pain and numbness in the occipitocervical region due to C2 nerve roots irritation during lateral mass screw replacement, which were not observed in the patients with C1 pedicle screw insertion. No complications such as screw loosening, shifting, breakage, or AAI were observed in both groups. Conclusions C1 pedicle screw fixation is less invasive and simpler, and has fewer complications. It renders better clinical outcomes than lateral mass screw fixation for treatment of AAI. Trial registration Current Controlled Trials ChiCTR-IOR-15006748 .

Background The transoral atlantoaxial reduction plate (TARP) is an effective advance in the treatment of atlantoaxial dislocation (AAD) and can enable the performance of anterior atlantoaxial release, reduction, decompression, and internal fixation in a one-stage operation. However, accurate transoral C2 pedicle insertion (C2TOPI) remains a challenge. The aim of this study is to develop a grouped patient-specific drill template (PDT) specifically for AAD with complete reduction and, furthermore, to compare its efficacy and accuracy in facilitating C2TOPI. Methods After CT scanning, ten cadaveric C2 specimens were randomly assigned to two groups (the PDT and freehand group). A grouped PDT specifically for AAD with complete reduction was designed and manufactured. C2TOPI was performed using the PDT or the fluoroscopy-guided freehand technique. Postoperative CT scans were subsequently performed to analyze the deviations at the centroid of the cross section at the midpoint of the pedicle. Screw position grades were also assessed in both groups. Results Compared to the freehand group, the PDT group had a significantly shorter surgery time ( p  < 0.001). Significant differences between the two groups were observed in the absolute value of the deviations at the centroid of the pedicle on either the axial or sagittal planes ( p  < 0.05). No significant difference was found in the screw positions between the two groups ( p  > 0.05); however, two unacceptable breaches (20%) occurred in the freehand group. Conclusion A specifically designed PDT could provide an accurate and easy-to-apply method for C2TOPI in AAD with complete reduction.

Purpose. To preliminarily evaluate the feasibility and accuracy of using rapid prototyping drill templates (RPDTs) for C1 lateral mass screw (C1-LMS) and C2 pedicle screw (C2-PS) placement. Methods. 23 formalin-fixed craniocervical cadaver specimens were randomly divided into two groups. In the conventional method group, intraoperative fluoroscopy was used to assist the screw placement. In the RPDT navigation group, specific RPDTs were constructed for each specimen and were used intraoperatively for screw placement navigation. The screw position, the operating time, and the fluoroscopy time for each screw placement were compared between the 2 groups. Results. Compared with the conventional method, the RPDT technique significantly increased the placement accuracy of the C2-PS (p<0.05). In the axial plane, using RPDTs also significantly increased C1-LMS placement accuracy (p<0.05). In the sagittal plane, although using RPDTs had a very high accuracy rate (100%) in C1-LMS placement, it was not statistically significant compared with the conventional method (p>0.05). Moreover, the RPDT technique significantly decreased the operating and fluoroscopy times. Conclusion. Using RPDTs significantly increases the accuracy of C1-LMS and C2-PS placement while decreasing the screw placement time and the radiation exposure. Due to these advantages, this approach is worth promoting for use in the Harms technique.

Background Patients with atlantoaxial dislocation combined with atlas occipitalization often present with variations in the anatomy of the vertebral artery and bone, posing potential risks during the implantation of the C2 pedicle screws during surgery. Objective Based on comprehensive preoperative imaging evaluation, this study investigates the blood supply, course, and relationship with bone of the vertebral artery in patients with atlantoaxial dislocation combined with atlas occipitalization, aiming to provide reference for safe implantation of internal fixation. Methods Imaging data of 77 patients with atlantoaxial dislocation combined with atlas occipitalization from October 2015 to December 2023 at the First Affiliated Hospital of the University of Science and Technology of China were collected, including CT, CT angiography, and MRI. The blood supply, course, and relationship with surrounding structure of the vertebral artery were analyzed using PACS and RadiAnt software. Results There were 18 males and 59 females, with an average age of 48.5 ± 10.5 years (range: 17–71 years). Forty-one cases (53.2%) were associated with congenital C2-3 fusion(Klippel-Feil syndrome). Vertebral artery blood supply was predominantly unilateral (including single blood supply) in 56 cases (72.7%), with left-sided predominance (62.5%). Segment V3 course variations of the vertebral artery were common, with 47 cases (35.6%) not entering the transverse foramen of C1. High-riding vertebral arteries were present in 36 cases (46.8%), with 22 cases (61.1%) associated with congenital C2-3 fusion. The average width of the axis pedicle on the high-riding side was 2.13 ± 1.2 mm, and the height of the isthmus was ≤ 5 mm, with an average of 2.55 ± 1.07 mm. There was a loose gap on the lateral side of the vertebral artery within the transverse foramen, with an average of 2.1 mm, and the corresponding width of the subarachnoid space on the inner side of the axis pedicle was 3.48 mm. Conclusion Comprehensive preoperative imaging evaluation can reduce the risk of vertebral artery injury during surgery in patients with congenital atlantoaxial dislocation combined with atlas occipitalization, and provide feasible and optimized internal fixation solutions.

Objectives The type of atlantodental space tissue in patients with atlantoaxial dislocation (AAD) can help doctors understand the possibility of reduction before surgery. However, relevant research on this topic is lacking. In this study, we aimed to summarise the atlantodental space classification of patients with AAD using magnetic resonance imaging (MRI) and explore their clinical characteristics. Materials and methods Preoperative 3T cervical MR images of patients who underwent posterior reduction and fixation surgery for non-traumatic AAD between 1 September 2012 and 31 July 2023 were collected. Two radiologists read and recorded the MRI results based on the standard protocol. The kappa value was used to evaluate intra- and inter-observer agreements. The patient’s age, sex, body mass index, clinical symptoms, Japanese Orthopaedic Association (JOA) score, and visual analogue scale information were obtained from medical records. Results A total of 135 patients with AAD (mean age, 51.3 ± 14.0 years, 52 men) were included in the analysis. The inter-observer agreement between the two readers was 0.818 ( P  < 0.0001). The intra-observer consistencies were 0.882 ( P  < 0.0001) and 0.896 ( P  < 0.0001). Patients with inflexible tissue signs exhibit more irreducible in hyperextension position, and their range of motion of ADI is smaller. These patients were older and had a higher incidence of abnormal spinal cord signals and JOA scores. Conclusions Novel MRI signs exhibited high inter- and intra-observer consistency and were associated with patient age, abnormal spinal cord signals, reducibility, range of motion of ADI, and symptoms.

Background context Studies have shown biomechanical superiority of cervical pedicle screw placement over other techniques. However, accurate placement is challenging due to the inherent risk of neurovascular complications. Navigation technology based on intraoperative 3D imaging allows highly accurate screw placement, yet studies specifically investigating screw placement in patients with traumatic atlantoaxial injuries are scarce. The aim of this study was to compare atlantoaxial screw placement as treatment of traumatic instabilities using iCT-based navigation or fluoroscopic-guidance with intraoperative 3D control scans. Methods This was a retrospective review of patients with traumatic atlantoaxial injuries treated operatively with dorsal stabilization of C1 and C2. Patients were either assigned to the intraoperative navigation or fluoroscopic-guidance group. Screw accuracy, procedure time, and revisions were compared. Results Seventy-eight patients were included in this study with 51 patients in the navigation group and 27 patients in the fluoroscopic-guidance group. In total, 312 screws were placed in C1 and C2. Screw accuracy was high in both groups; however, pedicle perforations > 1 mm occurred significantly more often in the fluoroscopic-guidance group ( P = 0.02). Procedure time was on average 23 min shorter in the navigation group ( P = 0.02). Conclusions This study contributes to the available data showing that navigated atlantoaxial screw placement proves to be feasible as well as highly accurate compared to the fluoroscopic-guidance technique without prolonging the time needed for surgery. When comparing these data with other studies, the application of different classification systems for assessment of screw accuracy should be considered.

During our clinical work, a special subtype of atlantoaxial dislocation(AAD) was identified, which was combined with atlas occipitalization and C2-3 fusion and was named as \"sandwich\" AAD.To explore if the biomechanical characteristics between atlantoaxial joints in “sandwich” deformity patients is particular and if there is a relationship between the AAD and the malformations (Chiari malformation and the formation of syringomyelia). A biomechanical study on the atlantoaxial joint by simulating “sandwich” deformity in cadaveric specimens was conducted. Five fresh frozen cadaver spinal specimens (from the occiput to C7) were selected from human donors with no history of spinal trauma and congenital malformations. The C0-1 and C2-3 (C1 pedicle screws combined with occipital titanium, C2 pedicle screws and C3 lateral mass screws) were fixed to develop congenital atlas occipitalization and C23 fusion deformities (“sandwich” deformity). Each specimen was tested two times, firstly under the normal condition and secondly under the “sandwich” condition. Then the range of motion(ROM) between C1 and C2 was measured under different conditions. The results showed that the relative range of flexion-extension motion between C1-2 in the “Sandwich” specimens was significantly greater than that in the normal specimens ( P  < 0.05). No significant difference in the relative range of other two motion modes (lateral bending and axial rotation) between C1-2 was observed for the normal and “Sandwich” specimens. The “clamp” mechanism of “sandwich” deformity during flexion and extension might be involved in the pathogenesis of AAD and secondary nervous system damage.