L Heemskerk Johan, Vega Carlos Perez, A Domingo Ricardo, R Richter Kent, Richter Reed, G Vivas-Buitrago Tito, T Neal Matthew, Quinones-Hinojosa Alfredo, Abode-Iyamah Kingsley
Department of Neurological Surgery, Mayo Clinic, Jacksonville, USA.
Department of Orthopedic Surgery, OLVG, Amsterdam, Netherlands.
Spine Surg Relat Res. 2021 Dec 27;6(4):350-357. doi: 10.22603/ssrr.2021-0073. eCollection 2022.
Plate distance is correlated with an increased incidence of adjacent segment pathologies (ASP). However, a correct plate-to-disk distance >5 mm is often not achieved. Therefore, this study aimed to quantify the effect of short plate-to-disk distance on the development of ASP using epidemiological measures in patients with cervical degenerative spine disease undergoing single-level anterior cervical discectomy and fusion (ACDFs).
Medical records of all patients with cervical degeneration undergoing single-level ACDF with plating (between January 2015 and December 2017), and a follow-up of at least 1 year, were reviewed retrospectively. Radiologic and clinical outcomes were assessed preoperatively, postoperatively, and at last follow-up. The plate-to-adjacent disk distance was measured, and epidemiological measures were calculated to quantify the risk on adjacent-level ossification development (ALOD) and adjacent segment degeneration (ASD).
Thirty-eight (47.5%) of the 80 patients developed ALOD, and 12 (15.0%) developed ASD after a 2-year follow-up. The incidence of ALOD was significantly lower if the plate was >5 mm away from the adjacent disk space compared to <5 mm (cranial adjacent segment, 22.5% vs. 51.3% [=0.010] and caudal, 21.4% vs. 47.8% [=0.029]). A correct plate-to-disk distance resulted in a relative risk reduction of 57.2% for the cranial segment and 56.0% for the caudal segment, with a number needed to treat of 4. The ASD was only observed in the cranial adjacent segments, and a correct plate-to-disk distance resulted in a relative risk reduction of 32.1% and a number needed to treat of 18.
Only four patients need to be treated with a correct plate-to-disk distance to avoid one case of ALOD. Therefore, it is advisable to keep the plate at a distance >5 mm away from the adjacent disk.
钢板距离与相邻节段病变（ASP）发生率增加相关。然而，通常无法实现正确的钢板与椎间盘距离>5mm。因此，本研究旨在采用流行病学方法，对接受单节段颈椎前路椎间盘切除融合术（ACDF）的颈椎退行性疾病患者中，钢板与椎间盘距离过短对ASP发展的影响进行量化。
回顾性分析2015年1月至2017年12月期间所有接受单节段ACDF并使用钢板固定、且随访至少1年的颈椎退变患者的病历。在术前、术后及末次随访时评估影像学和临床结果。测量钢板与相邻椎间盘的距离，并计算流行病学指标以量化相邻节段骨化发展（ALOD）和相邻节段退变（ASD）的风险。
80例患者中有38例（47.5%）在2年随访后发生ALOD，12例（15.0%）发生ASD。与钢板距离相邻椎间盘间隙<5mm相比，若钢板距离相邻椎间盘间隙>5mm，ALOD发生率显著降低（头侧相邻节段，22.5%对51.3%[=0.010]；尾侧，21.4%对47.8%[=0.029]）。正确的钢板与椎间盘距离使头侧节段的相对风险降低57.2%，尾侧节段降低56.0%，所需治疗人数为4。ASD仅在头侧相邻节段观察到，正确的钢板与椎间盘距离使相对风险降低32.1%，所需治疗人数为18。
仅需对4例患者采用正确的钢板与椎间盘距离进行治疗，即可避免1例ALOD。因此，建议将钢板与相邻椎间盘保持>5mm的距离。
