title: Reconstruction of a quadriceps tendon tear using Polyvinylidene fluoride sutures and patellar screw fixation: A biomechanical study.
abstract: BACKGROUND
  Acute quadriceps tendon tears are infrequent injuries requiring surgical treatment. Improved stability after surgical repair may allow for earlier weight-bearing and range of motion. Therefore, a new implant was tested and compared with the "gold standard", using transosseous sutures.
  
  
  METHODS
  Quadriceps tendon tears were constructed using a cadaveric model of 12 fresh matched-pair specimens (aged 61-97; mean age: 82 years). The biomechanical testing compared non-absorbable suture anchors (Polyvinylidene fluoride) versus transosseous absorbable sutures (Polydioxanon). Following anatomic reconstruction, the repaired specimens were loaded until they failed (testing machine: Hounsfield H10KM, Redhill, United Kingdom; maximum force: 1000 N; load speed: 25 mm/min; maximum test length: 150 mm; pre-load: 5 N). Values for load until tear displacement, maximum load until complete failure of the construct (pullout or breakage of the sutures or anchors) and stiffness of the reconstruction were recorded.
  
  
  RESULTS
  The stiffness found in the Polyvinylidene fluoride reconstruction (mean 9.83 N/mm) (standard deviation (SD) 7.75) showed a significant increase compared to the Polydioxanon reconstruction (mean 6.66 N/mm (SD 3.32); P=0.045). Transosseous fixation showed comparable results to the suture anchor system. There was no significant difference found in the maximum load to tear displacement (PVDF: 290.88 N (SD 106.01) vs. PDS: 266.75 N (SD 82.61); P=0.358).
  
  
  CONCLUSIONS
  Using the Polyvinylidene fluoride thread showed comparable results to the established method in reconstruction of ruptured quadriceps tendon. Stiffness of the Polyvinylidene fluoride thread reconstruction was even greater than Polydioxanon thread.
  
  
  CONCLUSIONS
  Improved stiffness may facilitate healing and is suggested as clinical relevance in reconstruction.
authors.affiliation: Department of Orthopaedic Trauma, Sana Klinikum Offenbach, Germany. Electronic address: Richard.Sellei@Sana.de.
authors.forename: R M
authors.initials: RM
authors.lastname: Sellei
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Bauer
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Hofman
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Kobbe
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Lichte
authors.affiliation: 10301 Kanis Road, Little Rock, AR 72205, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Garrison
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: H C
authors.initials: HC
authors.lastname: Pape
authors.affiliation: Department of Orthopaedic Trauma, RWTH Aachen University Hospital, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Horst
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D001863:Bone Screws; D002102:Cadaver; D006801:Humans; D008567:Membranes, Artificial; D008875:Middle Aged; D010329:Patella / Q000601:surgery*; D011145:Polyvinyls / Q000494:pharmacology*; D052097:Quadriceps Muscle / Q000293:injuries* / Q000601:surgery; D019651:Plastic Surgery Procedures / Q000379:methods*; D012421:Rupture; D013536:Suture Techniques / Q000295:instrumentation*; D013537:Sutures; D013708:Tendon Injuries / Q000503:physiopathology / Q000601:surgery*; D005465:Fluorocarbon Polymers
chemical_list: D008567:Membranes, Artificial; D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers
keywords: Bunnell suture; Polydioxanon thread; Polyvinylidene fluoride thread; Quadriceps tendon rupture; Suture anchor