Mummaneni Praveen V, Park Paul, Fu Kai-Ming, Wang Michael Y, Nguyen Stacie, Lafage Virginie, Uribe Juan S, Ziewacz John, Terran Jamie, Okonkwo David O, Anand Neel, Fessler Richard, Kanter Adam S, LaMarca Frank, Deviren Vedat, Bess R Shay, Schwab Frank J, Smith Justin S, Akbarnia Behrooz A, Mundis Gregory M, Shaffrey Christopher I
*Department of Neurosurgery and§§Department of Orthopaedic Surgery, University of California, San Francisco, California;‡Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan;§Weill Cornell Brain and Spine Center, New York, New York;¶Department of Neurological Surgery, University of Miami, Miami, Florida;‖San Diego Center for Spinal Disorders, La Jolla, California;#Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, New York, New York;**Department of Neurosurgery, University of South Florida, Tampa, Florida;‡‡Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania;¶¶Cedars-Sinai Spine Center, Los Angeles, California;‖‖Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois;##Rocky Mountain Scoliosis & Spine, Denver, Colorado;***Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
Neurosurgery. 2016 Jan;78(1):101-8. doi: 10.1227/NEU.0000000000001002.
Proximal junctional kyphosis (PJK) is a known complication after spinal deformity surgery. One potential cause is disruption of posterior muscular tension band during pedicle screw placement.
To investigate the effect of minimally invasive surgery (MIS) on PJK.
A multicenter database of patients who underwent deformity surgery was propensity matched for pelvic incidence (PI) to lumbar lordosis (LL) mismatch and change in LL. Radiographic PJK was defined as proximal junctional angle >10°. Sixty-eight patients made up the circumferential MIS (cMIS) group, and 68 were in the hybrid (HYB) surgery group (open screw placement).
Preoperatively, there was no difference in age, body mass index, PI-LL mismatch, or sagittal vertical axis. The mean number of levels treated posteriorly was 4.7 for cMIS and 8.2 for HYB (P < .001). Both had improved LL and PI-LL mismatch postoperatively. Sagittal vertical axis remained physiological for the cMIS and HYB groups. Oswestry Disability Index scores were significantly improved in both groups. Radiographic PJK developed in 31.3% of the cMIS and 52.9% of the HYB group (P = .01). Reoperation for PJK was 4.5% for the cMIS and 10.3% for the HYB group (P = .20). Subgroup analysis for patients undergoing similar levels of posterior instrumentation in the cMIS and HYB groups found a PJK rate of 48.1% and 53.8% (P = .68) and a reoperation rate of 11.1% and 19.2%, respectively (P = .41). Mean follow-up was 32.8 months.
Overall rates of radiographic PJK and reoperation for PJK were not significantly decreased with MIS pedicle screw placement. However, a larger comparative study is needed to confirm that MIS pedicle screw placement does not affect PJK.
近端交界性后凸（PJK）是脊柱畸形手术后已知的并发症。一个潜在原因是椎弓根螺钉置入过程中后肌肉张力带的破坏。
探讨微创手术（MIS）对PJK的影响。
对接受畸形手术患者的多中心数据库进行倾向匹配，以骨盆入射角（PI）与腰椎前凸（LL）不匹配及LL变化为指标。影像学PJK定义为近端交界角>10°。68例患者组成全椎弓根螺钉微创（cMIS）组，68例患者组成混合（HYB）手术组（开放螺钉置入）。
术前，两组在年龄、体重指数、PI-LL不匹配或矢状垂直轴方面无差异。cMIS组和HYB组后路治疗的平均节段数分别为4.7和8.2（P <.001）。两组术后LL和PI-LL不匹配均得到改善。cMIS组和HYB组的矢状垂直轴仍保持生理状态。两组的Oswestry功能障碍指数评分均显著改善。cMIS组31.3%发生影像学PJK，HYB组52.9%发生影像学PJK（P = 0.01）。cMIS组因PJK再次手术的比例为4.5%，HYB组为10.3%（P = 0.20）。对cMIS组和HYB组中接受相似后路内固定节段的患者进行亚组分析，发现PJK发生率分别为48.1%和53.8%（P = 0.68），再次手术率分别为11.1%和19.2%（P = 0.41）。平均随访32.8个月。
采用MIS椎弓根螺钉置入术，影像学PJK和因PJK再次手术的总体发生率并未显著降低。然而，需要更大规模的对照研究来证实MIS椎弓根螺钉置入术不会影响PJK。
