title: In vitro evaluation of the relationship between the semitendinosus muscle and cranial cruciate ligament in canine cadavers.
abstract: OBJECTIVE
  To evaluate the role of the semitendinosus muscle in stabilization of the canine stifle joint.
  
  
  METHODS
  Left stifle joints collected from cadavers of 8 healthy Beagles.
  
  
  METHODS
  Left hind limbs, including the pelvis, were collected. To mimic the tensile force of the quadriceps, gastrocnemius, and semitendinosus muscles, wires were placed under strain between the ends of each muscle. A sensor was used to measure the tensile force in each wire. Specimens were tested in the following sequence: cranial cruciate ligament (CrCL) intact, CrCL transected, released (tensile force of semitendinosus muscle was released in the CrCL-transected stifle joint), and readjusted (tensile force of semitendinosus muscle was reapplied in the CrCL-transected stifle joint). Specimens were loaded at 65.3% of body weight, and tensile force in the wires as well as the cranial tibial displacement were measured.
  
  
  RESULTS
  Tensile force for the CrCL-transected condition increased significantly, compared with that for the CrCL-intact condition. Mean ± SD cranial tibial displacement for the CrCL-transected condition was 2.1 ± 1.3 mm, which increased to 7.2 ± 2.3 mm after release of the tensile force in the semitendinosus muscle.
  
  
  CONCLUSIONS
  Results supported the contention that the semitendinosus muscle is an agonist of the CrCL in the stifle joint of dogs. Moreover, the quadriceps and gastrocnemius muscles may be antagonists of the CrCL. These findings suggested that the risk of CrCL rupture may be increased by diseases (such as cauda equina syndrome) associated with a decrease in activity of the semitendinosus muscle.
authors.affiliation: Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo, Japan. n.kanno7@gmail.com
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kanno
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Amimoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hara
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Harada
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nezu
authors.forename: Takuya
authors.initials: T
authors.lastname: Yogo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tagawa
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D001696:Biomechanical Phenomena; D002102:Cadaver; D004285:Dogs / Q000293:injuries* / Q000601:surgery; D005269:Femur / Q000293:injuries / Q000601:surgery; D006614:Hindlimb / Q000293:injuries* / Q000601:surgery; D018482:Muscle, Skeletal / Q000502:physiology*; D013264:Stifle / Q000502:physiology* / Q000601:surgery; D013977:Tibia / Q000293:injuries / Q000601:surgery