Lonner Baron S, Parent Stefan, Shah Suken A, Sponseller Paul, Yaszay Burt, Samdani Amer F, Cahill Patrick J, Pahys Joshua M, Betz Randal, Ren Yuan, Shufflebarger Harry L, Newton Peter O
Mount Sinai Hospital, E 101st St, New York, NY 100029, USA.
CHU Sainte-Justine Hospital Montreal, 3175 Ch de la Côte-Sainte-Catherine, Montreal, QC H3T 1C5, Canada.
Spine Deform. 2018 Mar-Apr;6(2):177-184. doi: 10.1016/j.jspd.2017.07.001.
Sagittal alignment abnormalities in Scheuermann kyphosis (SK) strongly correlate with quality of life measures. The changes in spinopelvic parameters after posterior spinal fusion have not been adequately studied. This study is to evaluate the reciprocal changes in spinopelvic parameters following surgical correction for SK.
Ninety-six operative SK patients (65% male; age 16 years) with minimum 2-year follow-up were identified in the prospective multicenter study. Changes in spinopelvic parameters and the incidence of proximal (PJK) and distal (DJK) junctional kyphosis were assessed as were changes in Scoliosis Research Society-22 (SRS-22) questionnaire scores.
Maximum kyphosis improved from 74.4° to 46.1° (p < .0001), and lumbar lordosis was reduced by 10° (-63.3° to -53.3°; p < .0001) at 2-year postoperation. Pelvic tilt, sacral slope, and sagittal vertical axis remained unchanged. PJK and DJK incidence were 24.2% and 0%, respectively. In patients with PI <45°, patients who developed PJK had greater postoperative T2-T12 (54.8° vs. 44.2°, p = .0019), and postoperative maximum kyphosis (56.4° vs. 44.6°, p = .0005) than those without PJK. In patients with PI ≥45°, patients with PJK had less postoperative T5-T12 than those without (23.6° vs. 32.9°, p = .019). Thoracic and lumbar apices migrated closer to the gravity line after surgery (-10.06 to -4.87 mm, p < .0001, and 2.28 to 2.10 mm, p = .001, respectively). Apex location was normalized to between T5-T8 in 68.5% of patients with a preoperative apex caudal to T8, whereas 90% of patients with a preoperative apex between T5 and T8 remained unchanged. Changes in thoracic apex location and lumbar apex translation were associated with improvements in the SRS function domain.
PJK occurred in 1 in 4 patients, a lower incidence than previously reported perhaps because of improved techniques and planning. Both thoracic and lumbar apices migrated closer to the gravity line, and preoperative apices caudal to T8 normalized in more than two-thirds of patients, resulting in improved postoperative function. Individualizing kyphosis correction to prevent kyphosis and PI mismatch may be protective against PJK.
休门氏后凸畸形（SK）的矢状面排列异常与生活质量指标密切相关。后路脊柱融合术后脊柱骨盆参数的变化尚未得到充分研究。本研究旨在评估SK手术矫正后脊柱骨盆参数的相互变化。
在前瞻性多中心研究中确定了96例接受手术治疗的SK患者（65%为男性；年龄16岁），随访时间至少2年。评估脊柱骨盆参数的变化以及近端（PJK）和远端（DJK）交界性后凸畸形的发生率，以及脊柱侧凸研究学会-22（SRS-22）问卷评分的变化。
术后2年时，最大后凸畸形从74.4°改善至46.1°（p <.0001），腰椎前凸减少了10°（从-63.3°至-53.3°；p <.0001）。骨盆倾斜度、骶骨倾斜度和矢状垂直轴保持不变。PJK和DJK的发生率分别为24.2%和0%。在骨盆入射角（PI）<45°的患者中，发生PJK的患者术后T2-T12角度（54.8°对44.2°，p = 0.0019）和术后最大后凸畸形角度（56.4°对44.6°，p = 0.0005）均大于未发生PJK的患者。在PI≥45°的患者中，发生PJK的患者术后T5-T12角度小于未发生PJK的患者（23.6°对32.9°，p = 0.019）。术后胸椎和腰椎顶点更靠近重力线（分别为-10.06至-4.87 mm，p <.0001，以及2.28至2.10 mm，p = 0.00）。术前顶点位于T8以下的患者中，68.5%的患者顶点位置在术后归一化至T5-T8之间，而术前顶点位于T5和T8之间的患者中，90%保持不变。胸椎顶点位置和腰椎顶点平移的变化与SRS功能域的改善相关。
四分之一的患者发生PJK，发生率低于先前报道，这可能是由于技术和规划的改进。胸椎和腰椎顶点均更靠近重力线，超过三分之二术前顶点位于T8以下的患者术后顶点位置归一化，从而改善了术后功能。个性化的后凸畸形矫正以防止后凸畸形和PI不匹配可能对预防PJK有保护作用。
