ArticleSurgical neurology international2025
Clinical features of atlas occipital assimilation: A retrospective study.
Article in Surgical neurology international, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
2 citing papers in PubMed.
- Atlanto-occipital assimilation with arcuate foramen, vertebral artery hypoplasia, and elongated styloid process: a case report.Anatomical science international · 2026Article
- Atlas posterior arch defect with Atlanto-occipital assimilation: Two case reports highlighting fracture mimicry and retro-odontoid pseudotumor.Surgical neurology international · 2026Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background: Atlas occipital assimilation (AOA) is a rare developmental anomaly of the craniocervical junction, with a poorly understood natural history. Therefore, in 15 cases, we reassess the clinical profile of three types of AOA. Methods: For 15 patients, we applied the 3 classifications: type 1 (4 patients; unilateral joint union (hemi-assimilation), type 2 (7 patients; bilateral joint union with atlas cleft (three-way), and type 3 (4 patients; bilateral joint union and complete union of the posterior arch (circumferential). Variables studied included age, sex, neurological status, pathological magnetic resonance findings, and clivo-axial angles (CAAs). Results: For these 15 patients, we discovered no significant gender differences. However, type 1 AOA affected younger people, type 2 involved more middle-aged/elderly people, and type 3 had most elderly population. Interestingly, all 7 type 2 patients were asymptomatic, and symptoms for the remaining patients included cough, headache, upper limb numbness (i.e., due to Chiari type 1 malformation [CM1] in type 1 patients), and myelopathy (i.e., due to spinal canal stenosis at C1-2 in type 3 patients). In addition, 75% of type 3 AOA patients had C2-3 fusions. The average CAA was 127.5° for type 1 and 139° for types 2 and 3. Decompressive surgery was performed for type 1 and decompression with fusions for type 3 patients. Conclusion: Half of the AOA cases are asymptomatic. However, symptomatic cases require attention to CM1 in young people and atlanto-axial dislocation in elderly people.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.