Characteristics of idiopathic atlanto-axial subluxation: a comparative radiographic study in patients with an idiopathic etiology and those with rheumatoid arthritis

Comparing Lumbar Spine Cages and Bone Grafts in Spinal Arthrodesis: A Meta-Analysis of Clinical Outcomes

INTRODUCTION AND AIM

The role of interbody cages in lumbar arthrodesis remains debated despite widespread adoption. This meta-analysis aimed to compare clinical and radiological outcomes between synthetic cages and structural bone grafts in lumbar fusion surgery from the latest updated evidence based on subgroup-based analysis and stratification of outcomes.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to conduct a literature search across major databases through December 2024. Studies comparing lumbar interbody fusion outcomes between cage and bone graft cohorts were included in this analysis. Random-effects meta-analyses were performed for fusion rates, radiographic parameters, clinical outcomes, and complications. Subgroup analyses stratified results by surgical approach, cage material, and graft type.

RESULTS

Twenty studies (1,452 patients) met inclusion criteria. Cage utilization demonstrated significantly higher fusion rates (96.3% versus 90.8%, RR=2.74, p=0.03) and greater disc height maintenance (MD=0.73 mm, 95% CI=0.45-1.01). Polyetheretherketone (PEEK) cages showed superior fusion rates compared to titanium (RR=1.00 versus 0.94, p=0.042). Back pain improvement was greater in the cage group (MD=0.65, 95% CI=0.08-1.22), while complication and reoperation rates remained comparable. No significant differences were observed in lordosis restoration or Oswestry Disability Index (ODI) scores.

CONCLUSIONS

Synthetic cage implementation in lumbar arthrodesis is associated with superior fusion rates and disc height maintenance, especially with PEEK devices. These benefits occur without increased complications, supporting cage utilization in appropriate clinical scenarios. Future studies should focus on long-term outcomes and cost-effectiveness analyses.

Multimodal Management of Coexisting Atlantoaxial Subluxation and Spinal Stenosis in an Older Adult: A Case Report and Literature Review

This case report investigates the diagnostic and therapeutic challenges caused by the coexistence of atlantoaxial subluxation and spinal stenosis in a 70-year-old male patient with chronic progressive numbness in both hands. A detailed assessment showed that the patient's symptoms were primarily caused by spinal stenosis, not atlantoaxial subluxation. Considering the patient's age and preference for nonsurgical treatment, a conservative chiropractic care plan was implemented, significantly improving his symptoms and quality of life. This case highlights the potential benefit of conservative chiropractic care in managing such complex cases, emphasizes the need for meticulous diagnosis, and requires further research to validate these findings and develop comprehensive management guidelines.

Atlantoaxial Subluxation Associated With Chronic Motor Tics

Head jerking is one of the most common symptoms of motor tics, and because of this, patients are at an increased risk of cervical spine disorders. However, there have been no reports of atlantoaxial subluxation in the English literature. To the best of our knowledge, this is the first case of atlantoaxial subluxation associated with chronic motor tics. A 41-year-old man with a history of chronic motor tics since childhood was diagnosed with high cervical myelopathy due to atlantoaxial subluxation. The patient underwent posterior fusion surgery using atlantoaxial instrumentation and an autologous bone graft. Although screw breakage occurred as an early postoperative instrumentation failure, the clinical outcome was excellent after surgery without recurrence of subluxation. Other techniques such as atlantoaxial transarticular fixation and occipitocervical fusion followed by long-term external immobilization might be treatment options at the initial surgery, or in case of postoperative recurrent atlantoaxial subluxation.

Open Reduction for Potentially Reducible Atlantoaxial Dislocation Secondary to Transverse Ligament Laxity in Patients with Rheumatoid Arthritis

OBJECTIVE

Atlantoaxial dislocation (AAD) is classified into reducible AAD and irreducible AAD (IRAAD). Anterior or posterior releasing followed by occipitocervical/atlantoaxial fusion is often performed for IRAAD, but is technically demanding. This study aimed to evaluate the results of the posterior open reduction technique without releasing the atlantoaxial joint in the treatment of potentially reducible AAD (PRAAD) caused by transverse ligament laxity in patients with rheumatoid arthritis (RA).

METHODS

Data from 38 RA patients who experienced PRAAD due to transverse ligament laxity were retrospectively reviewed. They all underwent posterior open reduction and fusion without releasing the atlantoaxial joint. Outcomes were evaluated by using atlantodental interval, modified Japanese Orthopedic Association scores, Nurick grade, Neck Disability Index, and visual analog scale score for neck pain.

RESULTS

All the patients achieved solid bone fusion at follow-up. The mean atlantodental interval was reduced to 5.6 ± 0.7 mm and 2.1 ± 0.5 mm after traction and operation, respectively, from a preoperative score of 8.2 ± 0.6 mm (P < 0.05). Compared with the respective preoperative values, the mean modified Japanese Orthopedic Association score and Nurick grade were significantly increased at the final follow-up (both P < 0.05), whereas the Neck Disability Index and visual analog scale score for neck pain were significantly decreased (both P < 0.05).

CONCLUSIONS

AAD with partial reduction after skeletal traction for 48 hours should be defined as PRAAD, not IRAAD. Open reduction with a C1-C2 pedicle screw-rod system can be safely and effectively applied in the treatment of PRAAD due to transverse ligament laxity in patients with RA.

Normal Atlanto-Occipital Interval in Adults of Southeast Nigeria: An Evaluation of the Effect of Age, Sex, and Race

BACKGROUND

Imaging of the craniocervical junction (CCJ) after trauma is crucial for injury detection and description. Of all the anatomic measurements of the CCJ, the normal value of atlanto-occipital interval (AOI) is not yet well established in adults. The aim of our study is to determine the normal values of the AOI in Nigerians aged between 21 and 60 years using multidetector computed tomography (MDCT) scan and to determine racial, age, and sex differences.

METHODS

This was a prospective observational study done at Memfys Hospital for Neurosurgery, Enugu, Nigeria, between May 2016 and April 2017. There were 240 subjects (120 men and 120 women) divided into the following age groups: 21-30, 31-40, 41-50, and 51-60 years. Non-Nigerians and those with preexisting CCJ abnormalities were excluded. Normal values were those within the 95% confidence interval. Results were analyzed for possible sex and age variations and compared with the available literature for racial differences. Ethical approval was obtained for this study.

RESULTS

The measured normal computed tomography value of the AOI in adult Nigerians was 1.181 ± 0.018 mm. The values in the age groups of 21-30, 31-40, 41-50, and 51-60 years were 1.279 ± 0.038, 1.164 ± 0.033, 1.151 ± 0.029, and 1.133 ± 0.033 mm, respectively (P < 0.05). The average normal values in men and women were 1.188 ± 0.025 and 1.174 ± 0.026 mm, respectively. The interobserver reliability test using the Cronbach α was 0.938.

CONCLUSIONS

AOI values in this study were higher than previous MDCT-based values in non-African populations. The AOI decreased linearly with age and did not show any sex difference.

Treatment of atlanto-axial subluxation secondary to rheumatoid arthritis by short segment stabilization with polyaxial screws

OBJECTIVE

The main aim of this study was to analyse the compex clinical and radiographic findings in a group of RA patients with atlanto-axial slip (AAS) treated with free-hand short C1 lateral mass and C2 trans-pedicular screw fixation. The surgical technique used and the pathology treated were the same in all patients, producing a very homogeneous cohort of patients This allowed the study and measurement of radiographic parameters and fusion process.

METHODS

Twenty-nine patients (21 female, 8 male, mean age 54.9 years, duration of RA 17.3 years) with AAS and without CS were treated by short C1/2 fixation. Mean follow-up was 4.5 years. Pain intensity was monitored using VAS. Radiographic assessment consisted of lateral cervical radiographs in neutral and dynamic views, MR and CT of the cervical spine. The AADI, PADI, AAA, sub-axial cervical Cobb angle and canal-clivus angle (CCA) were measured pre-operatively and during the follow-up.

RESULTS

Significant malposition was recorded in 4 (3.4%) out of 116 inserted screws. AADI, PADI, AAA and CCA values changed significantly after surgery and remained stable during follow-up. The Cobb C angle value showed no significant change after surgery. There was a significant decrease of the VAS after the surgery. Fusion or a stable situation was achieved in all patients at 2-year follow-up. Pannus regression was observed in the vast majority of patients; only in two cases was rheumatic tissue detected on MR at 2 years post-operatively.

CONCLUSION

C1 lateral mass and C2 trans-pedicular fixation with polyaxial screws followed by an autograft between C1 and C2 lamina allowed, with an acceptable complication rate and favourable clinical results, adequate slip reposition, introduction of optimal sagittal alignment in terms of the final AAA with no radiographic consequences for the sub-axial cervical spine and assurance of long-term stability.

Retrospective review of 22 surgically treated adults with congenital anomalies of the upper cervical spine: a clinical and radiological review

PURPOSE

The purpose of this study was to clarify the characteristics of adult cases with instability due to upper cervical spine anomalies who needed fusion surgery regarding the clinical and radiological findings.

METHODS

Twenty-two consecutive patients with instability due to upper cervical spine anomaly in adult cases were reviewed. The congenital anomalies included idiopathic atlanto-axial subluxation in nine cases, os odontoideum in seven cases, occipitalization of the atlas in four cases, atlanto-occipital subluxation in one case and AAS with another anomaly in one case. We evaluated the severity of neurological symptoms before surgery and at the last follow-up. We also observed MR images before and 1 year after surgery.

RESULTS

Before surgery, the 22 patients included seven Ranawat Grade I cases, ten Ranawat Grade II cases, and five Ranawat Grade IIIa cases. Regarding the neurological status after surgery, those included eighteen Ranawat Grade I cases, three Ranawat Grade II cases, and one Ranawat Grade IIIa case. Preoperative T2-weighted MR images demonstrated intramedullary high signal intensity (IHSI) in 12 cases. IHSI group did not include significantly more Ranawat Grade IIIa cases compared to the remaining 10 cases. In postoperative MR images (nine cases), the regression or disappearance of IHSI was demonstrated in only three cases.

CONCLUSIONS

In adult cases with instability due to upper cervical spine anomalies, we acquired favorable clinical outcomes after surgery. Regarding the neurological severity before surgery, there was no relationship with the IHSI on T2-weighted MR image. Moreover, the regression or disappearance of IHSI after surgery was not frequently demonstrated.