Article Figures & Data
Figures
- Fig. 1
The application of Dynesys system (case No. 9). A 70-year-old female patient was diagnosed with spinal stenosis and spondylolisthesis (A) and underwent fusion surgery at L4-5 previously 8 years prior to her visit (B). She developed back pain with intermittent claudication recently in the past year. Spinal stenosis was revealed at L3-4, and dynamic stabilization surgery was performed with Dynesys system at L3-4 (C). Postoperatively 3 years later, her symptoms were much improved with stable radiographic findings (D).
- Fig. 2
The application of NFlex system (case No. 14). A 46-year-old female patient underwent fusion surgery at L3-4 previously 2 years prior to her visit (A), but she complained of persistent pain (B). With more progressed spinal stenosis at L4-5, she underwent dynamic stabilization surgery with the NFlex system (C). No significant radiologic findings at adjacent segments were observed (D), but she maintained medical treatment for pain reduction.
- Fig. 3
Clinical outcomes. A) VAS change. Before non-fusion surgery, VAS was 7.4, and it gradually decreased after non-fusion surgery. VAS was 4.2 at 36 months postoperatively (p= 0.027). B) ODI change. ODI showed a change from 58.5% to 35.0% 36 months postoperatively (p=0.018).
- Fig. 4
MRI changes. A) Disc degeneration. Each segmental lumbar intervertebral disc gradually degenerated from the time before fusion surgery to after non-fusion surgery. Before non-fusion surgery, disc degeneration at L3-4 (*) showed statistically significant changes compared to that before fusion surgery (p=0.046). Between non-fusion surgery and the last MRI evaluation, the change at L1-2 (**) was statistically significant (p=0.032). B) Central stenosis. In the state between fusion and non-fusion surgery, stenosis at L3-4 (*) demonstrated significant degeneration (p=0.041) despite the fact that the L4-5 segment was decompressed by the fusion surgery. After non-fusion surgery, L3-4 (**) sufficient decompression was accomplished (p=0.041), but other instances of segmental stenosis did not show statistically significant changes. C) Facet joint degeneration. Each segmental facet joint was degenerated as time passed. However, the changes between fusion and non-fusion surgery and between non-fusion surgery and the last follow-up did not show statistical significance.
- Fig. 5
The change of disc degeneration on MRI (case No. 12). A 69-year-old female patient had spinal stenosis at L4-5 with multilevel disc degeneration (A). After a previous fusion surgery at L4-5 two years prior to her visit, spinal stenosis by thickening of the ligamentum flavum and disc degeneration at L2-3-4 had progressed (B). She underwent decompression and dynamic stabilization surgery at L2-3-4. At the postoperative 12-month MRI, segments at L1-2 and L5-S1 showed progression of disc degeneration (C).
- Fig. 6
Disc degeneration on lateral radiographs. Upon a comparison of disc degeneration before fusion and before non-fusion surgery and between each postoperative follow-up period, disc degeneration at L3-4 (*) was noted when comparing the state before the fusion surgery and that before the non-fusion surgery. After non-fusion dynamic stabilization surgery, disc degeneration gradually progressed, especially at L1-2 and L2-3.
Tables
- Table 1
MRI evaluation for disc degeneration, central stenosis, and facet joint degeneration.
Classification of disc degeneration Grade Signal intensity Structure Distinction of nucleus and anulus I Hyperintense, isointense to CSF Homogeneous, bright white Clear II Hyperintense, isointense to CSF Inhomogeneous with or without horizontal bands Clear III Intermediate Inhomogenous, gray Unclear IV Intermediate to hypointense Inhomogenous, gray to black Lost V Hypointense Inhomogenous, black Lost Classification of central canal stenosis Grade Definition 0 No lumbar stenosis without obliteration of anterior CSF space 1 Mild stenosis with separation of all cauda equina 2 Moderate stenosis with some cauda equine aggregated 3 Severe stenosis with none of the cauda equine separated Classification of facet joint degeneration Grade Criteria 0 Normal facet joint space (2-4mm width) 1 Narrowing of the facet joint space (< 2mm) and/or small osteophyte and/or mild hypertrophy of the articular process 2 Narrowing of the facet joint space and/or moderate osteophyte and/or moderate hypertrophy of the articular process and/or mild subarticular bone erosions 3 Narrowing of the facet joint space and/or large osteophytes and/or severe hypertrophy of the articular process and/or severe subarticular bone erosions and/or subchondral cysts CSF: cerebrospinal fluid.
Grade Disc space narrowing Osteophyte Endplate sclerosis I - - - II + - - III ± + - IV ± ± + ‘+’ indicates present; ‘-’, absence; ‘±’, either present or absent.
No. Gender Age at fusion surgery (yrs) Age at non-fusion surgery (yrs) Previous fusion segment Pain free period after fusion (m) Interval between fusion and non-fusion surgery (m) Feature of ASP Recent non-fusion segment Pedicle-based dynamic stabilization system Clinical ASP after non-fusion surgery Radiologic ASP after non-fusion surgery 1 M 49 59 L3-4 72 120 Stenosis at L4-5 DDD at L2-3, L4-5 L4-5 Dynesys + + 2 F 60 67 L4-5-S1 Persistent pain 84 Stenosis & DDD at L3-4 L3-4 Dynesys Persistent pain + 3 F 56 61 L4-5-S1 Persistent pain 60 Stenosis & DDD at L3-4 L3-4 Dynesys Persistent pain + 4 M 63 68 L4-5-S1 12 56 Stenosis at L3-4 L3-4 Dynesys - - 5 F 49 60 L4-5 96 120 Stenosis, DDD & SPL at L2-3-4 L2-3-4-5 Dynesys Persistent pain - 6 F 56 61 L3-4-5 36 60 Stenosis at L2-3 L2-3 Dynesys - - 7 F 61 63 L4-5 Persistent pain 26 Stenosis at L3-4-5 SPL at L4-5 L3-4-5 Dynesys + + 8 F 48 59 L4-5 48 120 Stenosis & DDD at L3-4 L3-4 Dynesys - - 9 F 62 70 L4-5 82 94 Stenosis & DDD at L3-4 L3-4 Dynesys - - 10 F 51 57 L4-5-S1 20 70 Stenosis & DDD at L3-4 L3-4 Dynesys - - 11 F 58 65 L4-5-S1 36 82 Stenosis at L1-2-3 L1-2-3 Dynesys - - 12 F 67 69 L4-5 20 22 Stenosis & DDD at L2-3-4 L2-3-4 NFlex - + 13 F 64 70 L4-5-S1 12 60 Stenosis at L3-4 L3-4 NFlex + - 14 F 43 46 L3-4 Persistent pain 25 Stenosis & DDD at L4-5 L4-5 NFlex + - 15 F 56 57 L2-3 Persistent pain 6 Stenosis at L4-5 L4-5 NFlex - - DDD: degenerative disc disease; SPL: spondylolisthesis; ‘+’: developed, ‘-’: absent.
In this issue
Jump to section
Related Articles
Cited By...
- No citing articles found.