title: A study to compare the efficacy of polyether ether ketone rod device with titanium devices in posterior spinal fusion in a canine model.
abstract: BACKGROUND
  The benefits of posterior lumbar fusion surgery with orthotopic paraspinal muscle-pediculated bone flaps are well established. However, the problem of non-union due to mechanical support is not completely resolved. The aim of the study was to compare the efficacy of polyether ether ketone (PEEK) rod device with conventional titanium devices in the posterior lumbar fusion surgery with orthotopic paraspinal muscle-pediculated bone flaps.
  
  
  METHODS
  This was a randomized controlled study with an experimental animal model. Thirty-two mongrel dogs were randomly divided into two groups-control group (n = 16), which received the titanium device and the treatment group (n = 16), which received PEEK rods. The animals were sacrificed 8 or 16 weeks after surgery. Lumbar spines of dogs in both groups were removed, harvested, and assessed for radiographic, biomechanical, and histological changes.
  
  
  RESULTS
  Results in the current study indicated that there was no significant difference in the lumbar spine of the control and treatment groups in terms of radiographic, manual palpation, and gross examination. However, certain parameters of biomechanical testing showed significant differences (p < 0.05) in stiffness and displacement, revealing a better fusion (treatment group showed decreased stiffness with decreased displacement) of the bone graft. Similarly, the histological analysis also revealed a significant fusion mass in both treatment and control groups (p < 0.05).
  
  
  CONCLUSIONS
  These findings revealed that fixation using PEEK connecting rod could improve the union of the bone graft in the posterior lumbar spine fusion surgery compared with that of the titanium rod fixation.
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150081, China.
authors.forename: Nanxiang
authors.initials: N
authors.lastname: Wang
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150081, China.
authors.forename: Huanxin
authors.initials: H
authors.lastname: Xie
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150081, China.
authors.forename: Chunyang
authors.initials: C
authors.lastname: Xi
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150081, China.
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150081, China. Nanxiang1986@sina.com.
authors.forename: Jinglong
authors.initials: J
authors.lastname: Yan
mesh_terms: D000818:Animals; D001577:Benzophenones; D001696:Biomechanical Phenomena; D016025:Bone Transplantation / Q000379:methods; D004285:Dogs; D007659:Ketones; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008422:Materials Testing / Q000379:methods; D023421:Models, Animal; D011092:Polyethylene Glycols; D011108:Polymers; D019736:Prostheses and Implants; D011474:Prosthesis Design; D011859:Radiography; D011897:Random Allocation; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D013524:Surgical Flaps; D014025:Titanium
chemical_list: D001577:Benzophenones; D007659:Ketones; D011108:Polymers; C063834:polyetheretherketone; D011092:Polyethylene Glycols; D014025:Titanium
keywords: Canine models; PEEK devices; Paraspinal muscle-pediculated bone flaps; Posterior lumbar fusion; Titanium rods