Schimmel Janneke J P, Poeschmann Marcel S, Horsting Philip P, Schönfeld Dirk H W, van Limbeek Jacques, Pavlov Paul W
Sint Maartenskliniek, Nijmegen, The Netherlands.
Clin Spine Surg. 2016 Jun;29(5):E252-8. doi: 10.1097/BSD.0b013e31826eaf74.
Historical cohort analysis.
Evaluation of mid-term clinical outcome and radiologic fusion in patients treated with a polyetheretherketone (PEEK) cage.
Anterior lumbar interbody fusion can be a good alternative in chronic low back pain when conservative treatment fails. Although titanium alloy cages give good fusion rates, disadvantages are the subsidence of the cage in the adjacent vertebrae and problematic radiologic evaluation of fusion. PEEK cages such as the Synfix-LR cage (Synthes, Switzerland) should overcome this.
From December 2004 until August 2007, 95 patients (21 double-level and 74 single-level) with degenerative disk disease from L3-S1 were operated by a single surgeon. The number of reoperations was counted. Radiologic fusion on computed tomography scan was scored with a new scoring system by an independent skeletal radiologist and orthopedic surgeon. Intraobserver agreement and specificity were assessed. Clinical improvement was measured by the Oswestry Disability Index score. The median duration of clinical follow-up was 47.7 months (range 29.9-61.6).
In total, 26 patients were reoperated after a median period of 17.6 months (range 6.7-46.9) of the initial surgery. Of the 26 patients, 23 patients (18 single-level and 5 double-level) were reoperated for symptomatic pseudarthrosis. A moderate agreement (κ=0.36) and a specificity of 70% and 37% for the radiologist and orthopedic surgeon, respectively, were found for scoring bony bridging. The Oswestry Disability Index score improved after initial surgery; however, reoperated patients reported a significantly lower improvement.
A high number of reoperations after an anterior lumbar interbody fusion procedure with the Synfix-LR cage were found, mainly because of symptomatic pseudarthrosis. The absence of posterior fixation in combination with lower stiffness and the hydrophobic characteristics of PEEK probably lead to insufficient initial stability, creating suboptimal conditions for bony bridging, and thus solid fusion. The proposed ease of the evaluation of radiologic fusion could not be supported. Clinicians should be alert on pseudarthrosis when patients treated with the Synfix-LR cage presented with persisted or aggravated complaints.
历史队列分析。
评估接受聚醚醚酮（PEEK）椎间融合器治疗的患者的中期临床疗效及影像学融合情况。
当保守治疗无效时，前路腰椎椎间融合术可作为慢性下腰痛的一种良好替代方法。尽管钛合金椎间融合器融合率良好，但其缺点是椎间融合器在相邻椎体下沉以及融合的影像学评估存在问题。诸如Synfix-LR椎间融合器（瑞士Synthes公司）之类的PEEK椎间融合器应能克服这些问题。
2004年12月至2007年8月，由一名外科医生为95例L3-S1节段退行性椎间盘疾病患者（21例双节段和74例单节段）实施手术。统计再次手术的次数。由一名独立的骨骼放射科医生和骨科医生采用一种新的评分系统对计算机断层扫描上的影像学融合情况进行评分。评估观察者内一致性和特异性。通过Oswestry功能障碍指数评分来衡量临床改善情况。临床随访的中位时间为47.7个月（范围29.9 - 61.6个月）。
总共26例患者在初次手术后中位时间17.6个月（范围6.7 - 46.9个月）后接受了再次手术。在这26例患者中，23例患者（18例单节段和5例双节段）因有症状的假关节形成而接受再次手术。在评估骨桥形成方面发现放射科医生和骨科医生的一致性为中等（κ = 0.36），特异性分别为70%和37%。初次手术后Oswestry功能障碍指数评分有所改善；然而，接受再次手术的患者报告改善程度明显较低。
发现使用Synfix-LR椎间融合器进行前路腰椎椎间融合术后再次手术的数量较多，主要原因是有症状的假关节形成。PEEK缺乏后路固定、较低的刚度以及疏水特性可能导致初始稳定性不足，为骨桥形成创造了欠佳的条件，从而影响坚固融合。所宣称的影像学融合评估的简便性未得到证实。当使用Synfix-LR椎间融合器治疗的患者出现持续或加重的不适时，临床医生应警惕假关节形成。
