Braun John T, Federico Sofia C, Lawlor David M, Grottkau Brian E
Massachusetts General Hospital, 55 Fruit St., Yawkey 3E, Boston, MA, 02114, USA.
Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
Spine Deform. 2025 Jul;13(4):1085-1098. doi: 10.1007/s43390-025-01077-0. Epub 2025 Mar 28.
Though multiple studies have reported tether rupture rates after anterior vertebral tethering (AVT) as high as 50%, few have adequately analyzed the clinical significance of tether rupture and factors that potentially increase the likelihood of revision surgery. We reviewed 262 consecutive adolescent idiopathic scoliosis (AIS) patients after AVT with the goal of identifying early and late tether ruptures and categorizing these tether ruptures as inconsequential, consequential, problematic, or beneficial. Our hypothesis was that the tether rupture rate after AVT for AIS would be significant but only a small percentage of patients would require revision surgery.
Charts, radiographs, and CT scans were reviewed for tether rupture in 262 consecutive AIS patients treated with AVT for thoracic and thoracolumbar/lumbar curves 33-77°. Early tether rupture occurred < 2 years and late tether rupture ≥ 2 years postoperatively. Tether rupture was further categorized as inconsequential (final curve < 40° and no pain), consequential (curve ≥ 40° and/or convex back pain), problematic (revision surgery required), or beneficial (improvement of overcorrection) at follow-up.
Of 262 consecutive AIS patients status post AVT (106 thoracic curves, 53 thoracolumbar curves, and 103 double curves), tether rupture was found in 45 patients with 66 curves (34 thoracic and 32 thoracolumbar/lumbar) treated at age 14.5 years and at Risser 2.6 and Sanders 4.7. Curves with tether rupture corrected from 50.3° preoperatively to 20.8° postoperatively, but lost 7.2° of correction with tether rupture settling at 28.0° final at 2.6 years (0-11 years). Early tether rupture occurred in 12/133 (9%) and late tether rupture in 33/129 (26%) patients with 2-11 year follow-up. Tether rupture was inconsequential in 67% (30/45) of patients, consequential in 13% (6/45), problematic in 16% (7/45), and beneficial in 4% (2/45). In those patients with tether rupture, 69% occurred in a thoracolumbar/lumbar curve and 47% demonstrated a rupture at L2,3. Revision surgery for a thoracolumbar/lumbar tether rupture involved tether replacement alone in 4 patients and thoracic fusion in 2 additional patients, 1 requiring thoracic fusion alone, and 1 requiring thoracic fusion with thoracolumbar/lumbar tether replacement (hybrid). Revision surgery for a thoracic tether rupture involved 1 tether replacement and 1 thoracic fusion. Revision surgery was unrelated to curve correction or loss of correction, but was related to multiple tether ruptures and convex back pain (p < 0.005).
This study demonstrated an early tether rupture rate of 9% and late tether rupture rate of 26% in a large series of patients treated with AVT for AIS over 14 years. While the majority of patients had inconsequential tether rupture (67%), with 7.2° loss of correction, a final curve < 40°, and no pain, a number of patients had consequential (13%) or problematic tether rupture (16%). These adversely affected patients had a final curve ≥ 40°, convex back pain, or required revision surgery. Additionally, a small number of patients (4%) actually benefitted from tether rupture by improvement in an area of impending overcorrection.
IV.
尽管多项研究报告称前路椎体栓系术（AVT）后栓系断裂率高达50%，但很少有研究充分分析栓系断裂的临床意义以及可能增加翻修手术可能性的因素。我们回顾了262例连续接受AVT治疗的青少年特发性脊柱侧凸（AIS）患者，目的是识别早期和晚期栓系断裂，并将这些栓系断裂分类为无关紧要、有影响、有问题或有益的。我们的假设是，AIS患者AVT后栓系断裂率会很高，但只有一小部分患者需要翻修手术。
回顾了262例连续接受AVT治疗胸段及胸腰段/腰段33 - 77°侧弯的AIS患者的病历、X线片和CT扫描，以确定栓系断裂情况。早期栓系断裂发生在术后<2年，晚期栓系断裂发生在术后≥2年。在随访时，栓系断裂进一步分类为无关紧要（最终侧弯<40°且无疼痛）、有影响（侧弯≥40°和/或凸侧背痛）、有问题（需要翻修手术）或有益（过度矫正改善）。
在262例连续接受AVT治疗的AIS患者中（106例胸段侧弯、53例胸腰段侧弯和103例双弯），45例患者出现栓系断裂，涉及66条侧弯（34条胸段和32条胸腰段/腰段），治疗时年龄为14.5岁，Risser征为2.6级，Sanders征为4.7级。发生栓系断裂的侧弯术前矫正角度为50.3°，术后为20.8°，但随着栓系断裂，矫正角度丢失7.2°，在2.6年（0 - 11年）时最终稳定在28.0°。在2 - 11年的随访中，12/133（9%）患者发生早期栓系断裂，33/129（26%）患者发生晚期栓系断裂。67%（30/45）的患者栓系断裂无关紧要，13%（6/45）有影响，16%（7/45）有问题，4%（2/45）有益。在那些发生栓系断裂的患者中，69%发生在胸腰段/腰段侧弯，47%在L2,3处出现断裂。胸腰段/腰段栓系断裂的翻修手术中，4例患者仅更换栓系，另外2例患者进行了胸段融合，1例仅需胸段融合，1例需要胸段融合并更换胸腰段/腰段栓系（混合手术）。胸段栓系断裂的翻修手术包括1例更换栓系和1例胸段融合。翻修手术与侧弯矫正或矫正丢失无关，但与多处栓系断裂和凸侧背痛有关（p < 0.005）。
本研究表明，在14年期间接受AVT治疗的大量AIS患者中，早期栓系断裂率为9%，晚期栓系断裂率为26%。虽然大多数患者的栓系断裂无关紧要（67%），矫正角度丢失7.2°，最终侧弯<40°且无疼痛，但仍有一些患者的栓系断裂有影响（13%）或有问题（16%）。这些受到不利影响的患者最终侧弯≥40°，有凸侧背痛或需要翻修手术。此外，少数患者（4%）实际上因栓系断裂而在即将出现过度矫正的区域得到改善而受益。
IV级。
