Yang Haisong, Lu Xuhua, He Hailong, Yuan Wen, Wang Xinwei, Liao Xinyuan, Chen Deyu
From the Department of Orthopaedic Surgery, Changzheng Hospital, Shanghai, China.
Spine (Phila Pa 1976). 2015 Apr 1;40(7):E388-93. doi: 10.1097/BRS.0000000000000800.
Retrospective case-control study.
To clarify the association between plate-to-disc distance (PDD) and adjacent-level ossification development (ALOD) and adjacent segment degeneration (ASD).
Anterior cervical discectomy and fusion with plating provides higher fusion rate and improved alignment but has been reported to result in ALOD and ASD.
We retrospectively reviewed 218 patients with solid fusion after anterior cervical arthrodesis with plating at our institution between January 2004 and December 2010. PDD was measured on postoperative lateral radiographs for each adjacent disc space and used to assign patients to 1 of 3 groups: group L, long PDD (>5 mm); group S, short PDD (0 mm ≤PDD ≤5 mm); and group N, PDD (<0 mm, disk space encroachment). Mean follow-up was 5.3 years. Incidences of cranial and caudal ALOD and ASD with and without symptoms were compared among groups. Severity of caudal ossification was not measured in 30 patients because bony overlap precluded adequate visualization of the caudal level.
Ossification developed in 134 (61%) of 218 cranial adjacent disc spaces and 45 (24%) of 188 caudal adjacent disc spaces (P < 0.01). Mean cranial PDD was shorter than mean caudal PDD (P < 0.01). Ossification rate was higher in group N than in group S at the cranial adjacent disc spaces (100% vs. 66%, P < 0.01). Incidences of both cranial and caudal ALOD were significantly higher in group S than in group L (66% vs. 31%, P < 0.01; and 31% vs. 13%, P < 0.01, respectively). No significant differences in symptomatic and asymptomatic ASD were seen among groups.
Longer PDD does not decrease the incidence of ASD but it can prevent ALOD. We now attempt to place anterior cervical plates of 5 mm or greater from adjacent disc spaces.
回顾性病例对照研究。
阐明钢板与椎间盘间距（PDD）与相邻节段骨化发展（ALOD）及相邻节段退变（ASD）之间的关联。
颈椎前路椎间盘切除及钢板融合术可提供更高的融合率并改善对线，但据报道会导致ALOD和ASD。
我们回顾性分析了2004年1月至2010年12月在我院接受颈椎前路融合钢板固定且融合稳固的218例患者。在术后的侧位X线片上测量每个相邻椎间盘间隙的PDD，并将患者分为3组之一：L组，PDD长（>5mm）；S组，PDD短（0mm≤PDD≤5mm）；N组，PDD（<0mm，椎间盘间隙侵犯）。平均随访时间为5.3年。比较各组有症状和无症状的头侧及尾侧ALOD和ASD的发生率。30例患者未测量尾侧骨化的严重程度，因为骨质重叠妨碍了对尾侧节段的充分观察。
218个头侧相邻椎间盘间隙中有134个（61%）发生骨化，188个尾侧相邻椎间盘间隙中有45个（24%）发生骨化（P<0.01）。头侧平均PDD短于尾侧平均PDD（P<0.01）。在头侧相邻椎间盘间隙，N组的骨化率高于S组（100%对66%，P<0.01）。S组头侧和尾侧ALOD的发生率均显著高于L组（分别为66%对31%，P<0.01；31%对13%，P<0.01）。各组有症状和无症状ASD的发生率无显著差异。
较长的PDD不会降低ASD的发生率，但可预防ALOD。我们现在尝试将颈椎前路钢板放置在距相邻椎间盘间隙5mm或更大距离处。
3级。
