Iizuka Haku, Iizuka Yoichi, Mieda Tokue, Kobayashi Ryoichi, Nishinome Masahiro, Ara Tsuyoshi, Sorimachi Yasunori, Nakajima Takashi, Takagishi Kenji
Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, Gunma, 371-8511, Japan.
Eur Spine J. 2015 Dec;24(12):2961-6. doi: 10.1007/s00586-015-4207-4. Epub 2015 Sep 2.
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.
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.
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.
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.
本研究旨在阐明因上颈椎畸形而需要融合手术的成年不稳定病例在临床和影像学方面的特征。
回顾了22例成年上颈椎畸形所致不稳定的连续病例。先天性畸形包括9例特发性寰枢椎半脱位、7例齿突骨、4例寰椎枕化、1例寰枕半脱位以及1例合并其他畸形的寰枢椎半脱位。我们评估了手术前及末次随访时神经症状的严重程度。还观察了手术前后的磁共振成像（MR）图像。
手术前，22例患者中包括7例Ranawat I级病例、10例Ranawat II级病例和5例Ranawat IIIa级病例。关于术后神经状态，包括18例Ranawat I级病例、3例Ranawat II级病例和1例Ranawat IIIa级病例。术前T2加权MR图像显示12例存在脊髓内高信号强度（IHSI）。与其余10例相比，IHSI组中Ranawat IIIa级病例并未显著更多。在术后MR图像（9例）中，仅3例显示IHSI消退或消失。
在因上颈椎畸形导致不稳定的成年病例中，我们术后获得了良好的临床效果。关于术前神经严重程度，与T2加权MR图像上的IHSI并无关联。此外，术后IHSI的消退或消失并不常见。
