title: Load and failure behavior of human muscle samples in the context of proximal femur replacement.
abstract: BACKGROUND
  To ensure adequate function after orthopedic tumor reconstruction, it is important to reattach the remaining soft tissue to the implant. This study aimed at obtaining mechanical properties of textile muscle-implant and muscle-bone connections in a preliminary test.
  
  
  METHODS
  Two groups of soft-tissue attachment were mechanically tested and compared: Native bone-muscle samples obtained from human femora and muscles attached to a prosthetic implant by means of Trevira® attachment tubes. Additionally, muscle samples were tested with muscle fibers aligned parallel and perpendicular to the tension load. A uniaxial load was exerted upon all samples.
  
  
  RESULTS
  Failure loads of 26.7 ± 8.8 N were observed for the native bone-muscle group and of 18.1 ± 9.9 N for the Trevira® group. Elongations of 94.8 ± 36.2 % were observed for the native bone-muscle group and 79.3 ± 51.8 % for the Trevira® group. The location of failure was mainly observed in the central area of the muscle fibers. Muscle fibers with parallel fiber orientation (47.6 ± 11.5 N) yielded higher tensile strength than those with perpendicular fiber orientation (14.8 ± 4.1 N).
  
  
  CONCLUSIONS
  Our experiments showed that higher forces were transmitted in the origin and insertion areas than in areas of flat soft tissue reconstruction using attachment tubes. The data indicate that the tested material allows reattaching muscles, but without reinforcing the insertion site. Therefore, attachment tubes with region-dependent and potentially anisotropic material behavior might be advantageous to optimize muscle-bone load transmission after surgery, which may allow lower complication rates and shorter physical recovery.
authors.affiliation: Department of Orthopedic, Trauma and Plastic Surgery, University of Leipzig, Liebigstraße 20, D-04103, Leipzig, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schleifenbaum
authors.affiliation: Department of Orthopedic, Trauma and Plastic Surgery, University of Leipzig, Liebigstraße 20, D-04103, Leipzig, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Institute of Anatomy, University of Leipzig, Liebigstraße 13, D-04103, Leipzig, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Möbius
authors.affiliation: Institute of Anatomy, University of Leipzig, Liebigstraße 13, D-04103, Leipzig, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wolfskämpf
authors.affiliation: Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital of Munich (LMU), Campus Grosshadern, Marchioninistraße 15, D-81377, Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Schröder
authors.affiliation: Fraunhofer-Institut für Werkzeugmaschinen und Umformtechnik IWU, Medizintechnik, Nöthnitzer Str. 44, D-01187, Dresden, Germany.
authors.forename: Ronny
authors.initials: R
authors.lastname: Grunert
authors.affiliation: Department of Anatomy, University of Otago, Lindo Ferguson Building, 270 Great King St., Dunedin, 9016, New Zealand. nlshammer@googlemail.com.
authors.forename: Niels
authors.initials: N
authors.lastname: Hammer
authors.affiliation: Department of Orthopedic, Trauma and Plastic Surgery, University of Leipzig, Liebigstraße 20, D-04103, Leipzig, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Prietzel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D002102:Cadaver; D005269:Femur / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures / Q000009:adverse effects / Q000295:instrumentation*; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D052097:Quadriceps Muscle / Q000503:physiopathology / Q000601:surgery*; D013718:Tensile Strength; D016474:Weight-Bearing
keywords: Mechanical properties; Muscle-attachment tubes; Muscle-bone connection; Proximal femoral reconstruction; Tumor orthopedic