title: Temporal changes in the tensile strength of ultra-high-molecular-weight polyethylene cable embedded in muscle tissue.
abstract: BACKGROUND
  Wires and cables have been used extensively for spinal sublaminar wiring, but damages to the spinal cord due to compression by metal wires have been reported. We have used more flexible ultra-high-molecular-weight polyethylene cable (Tekmilon tape) instead of metal wires since 1999 and have obtained good clinical outcomes. Although the initial strength of Tekmilon tape is equivalent to metal wires, the temporal changes in the strength of Tekmilon tape in the body should be investigated to show that sufficient strength is maintained over time until bone union is complete.
  
  
  METHODS
  Tekmilon tape was embedded into the paravertebral muscle of 10-week-old male Japanese white rabbits. Samples were embedded for 0, 1, 3, 6 or 12 months. At the end of each period, sequential straight tensile strength and sequential knot-pull tensile strength were measured.
  
  
  RESULTS
  The initial strength of Tekmilon tape in muscle tissue was maintained over time, with 92% straight tensile strength and 104% knot-pull tensile strength at 6months, and values of 77% and 100% at 12 months, respectively. Since single knot is clinically relevant, it is very important that the knot-pull tensile strength did not decrease over a 12-month period. This suggests that temporal changes in the tensile strength of Tekmilon tape are negligible at 1 year.
  
  
  CONCLUSIONS
  Tekmilon tape maintains sufficient strength in vivo until bone union has occurred. It is useful for sublaminar wiring instead of metal materials due to its flexibility and strength and may reduce the risk of neurological damage.
authors.affiliation: Department of Orthopedic Surgery, Nara Medical University, 840 Shijyo, Kashihara, Nara, Japan. matuhiro0311@hotmail.co.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsumori
authors.forename: Yurito
authors.initials: Y
authors.lastname: Ueda
authors.forename: Munehisa
authors.initials: M
authors.lastname: Koizumi
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Miyazaki
authors.forename: Hideki
authors.initials: H
authors.lastname: Shigematsu
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Satoh
authors.forename: Takuya
authors.initials: T
authors.lastname: Oshima
authors.forename: Masato
authors.initials: M
authors.lastname: Tanaka
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takakura
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D018482:Muscle, Skeletal / Q000601:surgery*; D011095:Polyethylenes / Q000737:chemistry*; D019736:Prostheses and Implants; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene