Application of interspinous dynamic stabilization in degenerative lumbar stenosis: a long-term follow-up study
PAN Ai-xing
HAI Yong
YANG Jin-cai
SU Qing-jun
GUAN Li
KANG Nan
LIU Yu-zeng
MENG Xiang-long
ZHANG Yang-pu
Abstract：Objective To evaluate the long-term outcomes of the application of interspinous dynamic stabilization in lumbar spinal stenosis ( LSS ). Methods Thirty patients ( 12 males and 18 females, aged from 46 - 77, 64.83 ± 11.83 on average ) with the diagnosis of LSS, treated by Coflex interspinous dynamic stabilization in our clinic from September 2007 to June 2009, were involved in this study. Clinical evaluations including visual analogue score ( VAS ) and Owestry Disability Index ( ODI ) were performed. Complications, reoperation rate, adjacent segment degeneration ( ASD ) rate were recorded. Meanwhile, radiographic measurements including intervertebral foraminal height ( IFH ), intervertebral space height ( ISH ), lumbar range of motion ( ROM ) were compared pre-operation, post-operation, and at the last follow-up. Results Twenty-five Coflex surgeries, 5 Topping-off surgeries ( Coflex combined with fusion ) were completed successfully. The average follow-up period was 94.6 months ( range:84 - 108 months ). Operation time: Coflex ( 76.5 ± 12.6 ) min; Topping-off ( 120.8 ± 17.5 ) min. Blood loss: Coflex ( 150.7 ± 24.8 ) ml; Topping-off ( 280.1 ± 30.1 ) ml. Hospital stay: Coflex ( 10.8 ± 1.9 ) days; Topping-off ( 12.5 ± 1.5 ) days. Differences were statistically significant ( P < 0.001 ). The postoperative VAS improved significantly in both groups [ Back pain: 6.87 ± 1.53 to 2.13 ± 0.78 ( P = 0.000 ). Leg pain: 7.81 ± 1.49 to 2.08 ± 0.83 ( P = 0.000 ) ]. The postoperative ODI evaluation improved significantly in both groups [ 54.2 ± 16.39 to 8.87 ± 2.86 ( P = 0.000 ) ]. As for imaging study, the intervertebral foraminal height ( IFH ) increased from ( 19.41 ± 1.74 ) mm ( pre-op ) to ( 22.14 ± 2.39 ) mm ( post-op ) and returned to ( 19.52 ± 2.87 ) mm ( last FU ). Intervertebral space height ( ISH ) increased from ( 9.96 ± 1.82 ) mm ( pre-op ) to ( 12.00 ± 2.06 ) mm ( post-op ) and returned to ( 9.19 ± 2.17 ) mm ( last FU ). No statistical significance existed in IFH and ISH ( P > 0.05 ). Range of motion ( ROM ) of the Coflex level had a slight drop from ( 5.70 ± 3.69 ) ° to ( 3.04 ± 2.31 ) ° ( P = 0.000 ), but the ROM of the adjacent segment was maintained. Three patients ( 10% ) presented ASD, 1 patient presented restenosis of the operated segment, and 1 patient presented degeneration on other segments, 4 ( 13.3% ) of them underwent the second surgery. Four patients ( 13.3% ) presented osteosynthesis of the spinous process around the Coflex. Two patients presented heterotopic ossification ( 6.7% ). Conclusions Coflex interspinous dynamic stabilization implanted after the decompression is long-term effective for LSS with acceptable complications and reoperation rate. Meanwhile, the Coflex could maintain the IFH, ISH and ROM of the operated level, which can effectively prevent the occurrence of ASD.
Keywords：Spinal stenosisLumbar vertebraeInternal fixatorsFollow-up studies
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 84-90 )