Department of Orthopaedics, Peking University Third Hospital, No 49 North Garden Street, HaiDian District, Beijing, 100191, People's Republic of China.
Department of Orthopedics, NYU Langone Orthopedic Hospital, New York, NY, USA.
BMC Musculoskelet Disord. 2020 Dec 7;21(1):821. doi: 10.1186/s12891-020-03852-8.
In the setting of congenital C1 occipitalization and C2-3 fusion, significant strain is placed on the atlantoaxial joint. Vertebral fusion both above and below the atlantoaxial joint (i.e., a "sandwich") creates substantial instability. We retrospectively report on a case series of "sandwich fusion" atlantoaxial dislocation (AAD), describing the associated clinical characteristics and detailing surgical treatment. To the best of our knowledge, the present study is the largest investigation to date of this congenital subgroup of AAD.
Seventy consecutive patients with sandwich fusion AAD, from one senior surgeon, were retrospectively reviewed. The clinical features and the surgical treatment results were assessed using descriptive statistics. No funding sources or potential conflict of interest-associated biases exist.
The mean patient age was 42.2 years (range: 5-77 years); 36 patients were male, and 34 were female. Fifty-eight patients (82.9%) had myelopathy, with Japanese Orthopaedic Association (JOA) scores ranging 4-16 (mean: 12.9). Cranial neuropathy was involved in 10 cases (14.3%). The most common presentation age group was 31 to 40 years (24 cases, 34.3%). Radiological findings revealed brainstem and/or cervical-medullar compression (58 cases, 82.9%), syringomyelia (16 cases, 22.9%), Chiari malformation (12 cases, 17.1%), cervical spinal stenosis (10 cases, 14.3%), high scapula deformity (1 case, 1.4%), os odontoideum (1 case, 1.4%), and dysplasia of the atlas (1 case, 1.4%). Computed tomography angiography was performed in 27 cases, and vertebral artery (VA) anomalies were identified in 14 cases (51.9%). All 70 patients underwent surgical treatment, without spinal cord or VA injury. Four patients (5.7%) suffered complications, including 1 wound infection, 1 screw loosening, and 2 cases of bulbar paralysis. In the 58 patients with myelopathy, the mean JOA score increased from 12.9 to 14.5. The average follow-up time was 50.5 months (range: 24-120 months). All 70 cases achieved solid atlantoaxial fusion at the final follow-up.
Sandwich fusion AAD, a unique subgroup of AAD, has distinctive clinical features and associated malformations such as cervical-medullar compression, syringomyelia, and VA anomalies. Surgical treatment of AAD was associated with myelopathy improvement and minimal complication occurrence.
在先天性 C1 枕化和 C2-3 融合的情况下，寰枢关节承受着显著的压力。寰枢关节上下方的椎体融合（即“三明治”）会导致严重的不稳定。我们回顾性报告了一系列“三明治融合”寰枢关节脱位（AAD）病例，描述了相关的临床特征，并详细介绍了手术治疗方法。据我们所知，目前的研究是对这种先天性 AAD 亚组的最大调查。
对一位资深外科医生治疗的 70 例“三明治融合”AAD 患者进行回顾性分析。使用描述性统计方法评估临床特征和手术治疗效果。无资金来源或潜在的与利益冲突相关的偏倚。
患者的平均年龄为 42.2 岁（5-77 岁）；36 例为男性，34 例为女性。58 例（82.9%）有脊髓病，日本骨科协会（JOA）评分 4-16 分（平均 12.9 分）。10 例（14.3%）有颅神经受累。最常见的发病年龄组为 31-40 岁（24 例，34.3%）。影像学发现脑干和/或颈髓受压（58 例，82.9%）、脊髓空洞症（16 例，22.9%）、小脑扁桃体下疝畸形（12 例，17.1%）、颈椎管狭窄（10 例，14.3%）、高肩胛畸形（1 例，1.4%）、齿状突缺如（1 例，1.4%）和寰枢椎发育不良（1 例，1.4%）。27 例行 CT 血管造影，发现椎动脉（VA）异常 14 例（51.9%）。70 例患者均行手术治疗，无脊髓或 VA 损伤。4 例（5.7%）发生并发症，包括 1 例伤口感染，1 例螺钉松动，2 例延髓麻痹。在 58 例有脊髓病的患者中，JOA 评分从 12.9 分提高到 14.5 分。平均随访时间为 50.5 个月（24-120 个月）。70 例患者在末次随访时均获得寰枢关节牢固融合。
“三明治融合”AAD 是 AAD 的一个独特亚组，具有独特的临床特征和相关畸形，如颈髓受压、脊髓空洞症和 VA 异常。AAD 的手术治疗与脊髓病改善和并发症少有关。
