title: Clinical efficacy and safety of a new flexible interbody spacer system.
abstract: BACKGROUND
  Patients with lumbar degenerative disk disease (DDD) often require an interbody fusion. Several spacer systems have been developed to achieve an adequate fusion. The newly developed flexible interbody spacer system (Luna®, Benvenue Medical Inc.) expands to the disk space and is adjustable to the patient's anatomy.
  
  
  OBJECTIVE
  Prospective monocentric evaluation of interbody fusions performed with the new system in patients with DDD to assess the device's efficacy and safety.
  
  
  METHODS
  The study includes patients with DDD of one or two contiguous lumbar levels. All patients were treated with the new flexible cage system. To evaluate the clinical outcome, examinations were conducted preoperatively, 6 weeks, 6 months and 12 months postoperatively. At each study visit possible implant loosening was assessed by plain radiography and any adverse events were documented. Furthermore, back pain was evaluated using the visual analogue scale (VAS), functional impairment using the Oswestry-Disability-Index (ODI) and quality of life using the SF36.
  
  
  RESULTS
  A total of 30 patients (age: 52.8 ± 11 years, gender: 53% male) were included. None of the patients showed signs of implant loosening and the total number of adverse events was low (3%). The VAS improved significantly from 81.2 ± 9.5 mm at baseline to 28 ± 26.2 mm after 12-months (p ≤ 0.0001). The ODI also improved significantly from 57.9 ± 9.6% at baseline to 20 ± 15.6% after 12-months (p ≤ 0.0001). The physical component score (PCS) of the SF36 improved significantly ongoing from 29.2 ± 9.3 at baseline to 56.1 ± 14.9 after 12-months (p = 0.0079) and the mental component score (MCS) improved significantly from 49.2 ± 20.7 at baseline to 62.8 ± 18.9 after 12 months (p = 0.013).
  
  
  CONCLUSIONS
  Minimal-invasive lumbar interbody fusion with the new flexible system is a safe and effective treatment method for patients with DDD. Complication rates are low and treatment leads to an improvement of pain, functional impairment and quality of life.
authors.forename: Tom R
authors.initials: TR
authors.lastname: Jansen
authors.forename: Rahel
authors.initials: R
authors.lastname: Bornemann
authors.forename: Philip P
authors.initials: PP
authors.lastname: Roessler
authors.forename: Yorck
authors.initials: Y
authors.lastname: Rommelspacher
authors.forename: Andreas C
authors.initials: AC
authors.lastname: Strauss
authors.forename: Sönke P
authors.initials: SP
authors.lastname: Frey
authors.forename: Kirsten
authors.initials: K
authors.lastname: Sander
authors.forename: Dieter C
authors.initials: DC
authors.lastname: Wirtz
authors.forename: Robert
authors.initials: R
authors.lastname: Pflugmacher
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000601:surgery*; D017116:Low Back Pain; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019736:Prostheses and Implants; D011788:Quality of Life; D013123:Spinal Fusion / Q000379:methods*
keywords: Degenerative disk disease; flexible interbody fusion