title: Functional and radiological outcomes of semi-rigid dynamic lumbar stabilization adjacent to single-level fusion after 2 years.
abstract: OBJECTIVE
  To prospectively evaluate the functional and radiological outcomes of Isobar semi-rigid dynamic posterior stabilization adjacent to single-level fusion up to and including 24 months postoperatively.
  
  
  METHODS
  A prospective follow-up for 24 months of 36 patients who underwent posterior Isobar dynamic stabilization due to single-level degenerative lumbar discopathy and instability (DLDI) with mild adjacent level degeneration, with collection of functional [visual analog scale (VAS) and Oswestry Disability Index (ODI)] and radiological data (resting, functional X-rays and MRI).
  
  
  RESULTS
  Functional outcomes at 24 months showed significant improvement in mean VAS score by 38.9 points (P < 0.01) and ODI by 22.4 points (P < 0.01). Compared with data preoperatively, disc height at the index and adjacent levels and intervertebral angle (IVA) at the index level showed a slight decreasing trend at each follow-up (P > 0.05), while IVA at the adjacent level showed a slight increasing trend (P > 0.05). Range of motion averaged 2.84° at the index level and remained unchanged at the adjacent level (P > 0.05). The mean Pfirrmann score changed from 2.86 preoperatively to 2.92 at 24 months postoperatively at the index level (P > 0.05), and from 1.92 preoperatively to 1.96 at 24 months postoperatively at the adjacent level (P > 0.05). No reoperation, loosening of screws or infection was recorded.
  
  
  CONCLUSIONS
  Patients with single-level DLDI and mild adjacent level degeneration treated with Isobar stabilization show a clinical improvement after 2 years. However, disc degeneration at the index and adjacent levels seems to continue despite using semi-rigid dynamic stabilization.
authors.affiliation: Department of Orthopaedic Surgery, Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, 639 Zhizaoju Road, 200011, Shanghai, People's Republic of China.
authors.forename: Lingjie
authors.initials: L
authors.lastname: Fu
authors.forename: Alexandra
authors.initials: A
authors.lastname: France
authors.forename: Youzhuan
authors.initials: Y
authors.lastname: Xie
authors.forename: Kai
authors.initials: K
authors.lastname: Fang
authors.forename: Yaokai
authors.initials: Y
authors.lastname: Gan
authors.forename: Pu
authors.initials: P
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000601:surgery*; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000517:prevention & control*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000295:instrumentation*; D010147:Pain Measurement; D011446:Prospective Studies; D019736:Prostheses and Implants; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular; D012086:Reoperation; D013123:Spinal Fusion / Q000009:adverse effects; D016896:Treatment Outcome