颈椎前路钢板固定融合术后邻近节段骨化发生的因素

Development of adjacent level ossification in patients after fixation with anterior cervical plate

目的:探讨颈椎前路钢板固定融合术后发生邻近节段骨化的相关因素。方法:回顾分析因颈椎退行性变行颈椎前路钢板固定融合术后患者的影像学资料,将患者分组,A组:钢板至邻近节段椎间盘的距离<5mm;B组:钢板至邻近节段椎间盘的距离≥5mm。术后平均随访26个月,相邻节段的骨化程度按0级(无骨化)到3级(完全桥接)划分。结果:钢板上端邻近节段的骨化发生率(35%)显著高于钢板下端(16%)(P<0.01)。A组的骨化发生率高于B组,且A组有13例的骨化程度是2级～3级。结论:颈椎前路钢板固定融合术后邻近节段骨化与钢板和邻近椎间隙的距离相关,钢板距离邻近节段椎间盘越近,发生骨化的可能性越大。钢板两端距离相邻椎间隙>5mm能降低邻近节段中度到重度骨化的发生。

Objective：To explore the reason of adjacent level ossification after fixation with anterior cervical plate.Methods：We retrospectively reviewed the radiographs of the cervical spine patients who had a solid fusion following an anterior cervical arthrodesis with a plate for the treatment of a degenerative cervical condition.None of the patients had had cervical spine surgery prior to the arthrodesis.The plate-to-disc distance was measured on the postoperative radiograph and was used to divided the patients into 2 groups for each of the adjacent disc spaces.In group A,the plate-to-disc distance was 〈5mm,and in group B, it was ≥5mm. The mean duration of follow-up was 26 months.The severity of the ossification at the two adjacent disc spaces was classified on a scale ranging from grade 0（no ossification）to grade 3（complete bridging）.Results：Ossification developed in 24（35%）patients in the cephalad adjacent disc spaces and 11 （16%）in the caudal adjacent disc spaces.The mean cephalad plate-to-disc distance was shorter than the mean caudal adjacent disc spaces.The rate of ossification was higher in group A than in group B.In addition,all the 13 cases of moderate-to-severe ossification developed in group A.Conclusion：There is a positive association between adjacent level ossification following anterior cervical plate and the plate-to-disc distance.Placing anterior cervical plates at least 5 mm away from the adjacent disc spaces can decrease the rate of moderate-to-severe adjacent level ossification.