Faulks Charlie R, Biddau Dean T, Rossi Vincent J, Brazenor Graeme A, Malham Gregory Michael
Neuroscience Institute, Epworth Hospital, Richmond, Melbourne, Australia.
Department of Neurosurgery, Atrium Health Musculoskeletal Institute, Charlotte, NC, USA.
J Spine Surg. 2022 Sep;8(3):304-313. doi: 10.21037/jss-22-36.
The motion preserving benefits of lumbar total disc replacement (LTDR) are well established. There is a paucity of long-term follow-up data on the M6-L prosthesis. The aim was to evaluate the clinical and radiographic outcomes of patients undergoing LTDR with M6-L and make comment about its effectiveness and durability.
A retrospective single center chart review was performed of all patients who underwent LTDR with M6-L between January 1, 2011, and January 1, 2021, either as standalone device or combined with a caudal anterior lumbar interbody fusion (ALIF) (hybrid procedure). Preoperative, postoperative, and final follow-up patient reported outcome measures (PROMs) (VAS back, VAS leg, ODI, and SF-12) and patient satisfaction were recorded prospectively. Device range of motion (ROM), adjacent segment degeneration/disease and heterotopic ossification (HO) were obtained from flexion and extension lumbar radiographs at most recent follow-up.
Sixty patients underwent LTDR with the M6-L device. Mean age was 41 [16-71] years and 38 (63%) were male. Sixteen (26.7%) underwent standalone LTDR, 42 (70.0%) a hybrid procedure, and 2 (3.3%) a 3-level procedure. Twenty-three (38.3%) patients were lost to follow-up. Thirty-seven (61.7%) were followed for a mean of 4.3 [1-10] years with 36/37 reviewed at a minimum of 2-years and 13/37 followed for over 5-years. Only one patient with osteopenia needed index level revision LTDR surgery for subsidence requiring supplemental posterior instrumentation. There were no osteolysis induced device related failures. Thirty patients obtained long-term follow-up radiographic data. Six patients had adjacent segment degeneration; none required surgery for adjacent segment disease (ASD). Three patients presented with clinically significant HO (2 with McAfee class III, 1 with class IV). The average M6-L ROM was 8.6 degrees. Mean preoperative baseline PROMs demonstrated statistically significant improvements postoperatively and were sustained at last follow-up (P<0.05).
Total disc replacement (TDR) with M6-L showed clinically significant improvement in PROMs that were sustained at long-term follow-up. There were no osteolysis induced device related failures. The device ROM was maintained and showed a downward trend over the 10-year study follow-up period. This paper demonstrated that the M6-L was an effective and durable arthroplasty device in this series.
腰椎全椎间盘置换术（LTDR）保留运动功能的益处已得到充分证实。关于M6-L假体的长期随访数据较少。本研究旨在评估接受M6-L型LTDR患者的临床和影像学结果，并对其有效性和耐久性进行评价。
对2011年1月1日至2021年1月1日期间接受M6-L型LTDR的所有患者进行回顾性单中心图表审查，这些患者接受的手术方式为单独使用该假体或联合尾侧前路腰椎椎间融合术（ALIF）（混合手术）。前瞻性记录术前、术后及末次随访时患者报告的结局指标（PROMs）（腰部视觉模拟评分、腿部视觉模拟评分、Oswestry功能障碍指数和SF-12）以及患者满意度。在最近一次随访时，通过腰椎屈伸位X线片获取假体活动范围（ROM）、相邻节段退变/疾病及异位骨化（HO）情况。
60例患者接受了M6-L型假体LTDR手术。平均年龄为41岁（16 - 71岁），男性38例（63%）。16例（26.7%）接受单独LTDR手术，42例（70.0%）接受混合手术，2例（3.3%）接受三节段手术。23例（38.3%）患者失访。37例（61.7%）患者获得随访，平均随访时间为4.3年（1 - 10年），其中36/37例至少随访2年，13/37例随访超过5年。仅1例骨质疏松患者因假体下沉需要补充后路内固定而进行了翻修手术。没有因假体周围骨溶解导致的与假体相关的失败病例。30例患者获得了长期随访影像学资料。6例患者出现相邻节段退变；均无需因相邻节段疾病（ASD）进行手术。3例患者出现具有临床意义的HO（2例为McAfee III级，1例为IV级）。M6-L假体的平均活动范围为8.6度。术前平均基线PROMs在术后有统计学意义的改善，并在末次随访时得以维持（P<0.05）。
M6-L型全椎间盘置换术（TDR）在PROMs方面显示出具有临床意义的改善，且在长期随访中得以维持。没有因假体周围骨溶解导致的与假体相关的失败病例。假体活动范围得以维持，并且在10年的研究随访期内呈下降趋势。本文表明，在本系列研究中，M6-L是一种有效且耐用的关节置换装置。
