單側前位經寰樞椎關節螺絲釘固定術治療不穩定之第1-2頸椎病變合併第二型樞椎齒突骨折之案例報告

Unilateral anterior transarticular screw fixation for atlantoaxial instability combined with type II odontoid fracture. Case report

傳統上，我們會用後位經寰樞椎關節螺絲釘固定術治療不穩定之第1-2頸椎病變合併第二型樞椎齒突骨折。它有高達95-100%的融合率。然而也同時有著高達20%的致殘與致死率。因此、前位固定術對於不需要減壓的病人是一個更好的方式。它有著較安全和較少的組織破壞。案例是個本身有風濕性關節炎病史的老人。外傷後產生無法忍受的頸部疼痛。動態影像檢查顯示寰樞椎關節不穩定。核磁共振顯示第二型樞椎齒突骨折與假性骨樣增生但無後側減壓之需要。回顧目前的文獻、前側固定術對於這樣不需要後側減壓但又需要寰樞椎關節固定的病人是個好的方式。我們選擇了這樣的術式並且報告指有一邊的固定也是可以有好的止痛效果、並且在八個月後仍然證實是有效的穩定度。這樣一個步驟顯然是有效的而且是安全的。也防止進一步的假性骨增生。在目前的台灣文獻裡、這是第一個報導的單側前位經寰樞椎關節螺絲釘固定術。

To treat type II odontoid fracture combined with atlantoaxial instability, traditionally we can do internal fixation of posterior transarticular screws. Fusion rate was documented very high (95-100%). However, the morbidity and mortality were around 20%. Anterior transarticular screws is an alternative method for patients who need C1-2 fixation only. This approach is a minimal invasive and safer procedure on neurovascular injury. An elderly patient with rheumatoid arthritis suffered from intractable pain on neck after traumatic episode. Dynamic cervical spine radiographs showed instability of C1-2 articulation. MRI studies revealed type II odontoid fracture with pseudoarthrosis. The spinal cord was free from compression. Review of previous literatures of ATS fixation suggested a good choice for atlantoaxial instability without need of posterior decompression than traditional posterior transarticular screw fixation. Based on previous studies, we applied unilateral anterior transarticular screw fixation and obtained a good and immediate pain relief. The stability of C1-C2 was maintained after 8-month follow-up. We present a good outcome of unilateral ATS fixation on C1-2 and believe this procedure is safe and efficient to achieve stabilization and prevent odontoid pseudoarthrosis. To the best of the authors’ knowledge, this is the first report of this unilateral fusion method in Taiwan literature.