title: [Lesions of the popliteus system and their significance for the stability of the knee joint].
abstract: BACKGROUND
  Stäubli postulated a clinical significance of lesions to the popliteus system because of a 95% incidence in acute and 85.7% in chronic ruptures of the cruciate ligaments. The sparse clinical literature on this topic favours conservative or operative treatment as well.
  
  
  OBJECTIVE
  What is the significance of isolated lesions of the popliteus tendon on translational stability of the knee joint?
  
  
  METHODS
  The popliteus tendon was severed in six sheep. One year postop. the knee joints were evaluated by means of x-ray, biomechanical testing, computed tomography osteoabsorptiometry (CTOAM) and micromorphology.
  
  
  RESULTS
  There were no pathological findings on x-ray. The simulation of the trauma situation ex vivo showed no instability whereas increased translation and progressive loosening of secondary stabilizers was found after one year (posterior and total aptranslation, compliance index p < 0.05). The position of the density maxima of the subchondral mineralization are about the same on the operated and the non-operated knee joint. All tendons healed macroscopically, but micromorphology exhibited a persisting increase of cross-sectional areas, a low differentiated ultrastructure of the tendon and an increased cellularity (p < 0.01).
  
  
  CONCLUSIONS
  
  
  
  METHODS
  1. intraarticular, extrasynovial tendons heal spontaneously even within the synovial environment; 2. healing is defective even one year postop.; 3. the postulate of the significance of the popliteus system for the stability of the knee is proven. Clinical: 1. (isolated) lesions of the popliteus go undetected with clinical and instrumented examination; 2. conservative treatment eventually results in increased posterior translational instability; 3. this will increase strain and load on the menisci and ACL- reconstructions.
authors.affiliation: Sektion Unfallchirurgie, Technischen Universität München.
authors.forename: M A
authors.initials: MA
authors.lastname: Scherer
authors.forename: G
authors.initials: G
authors.lastname: Metak
authors.forename: H
authors.initials: H
authors.lastname: Anetzberger
authors.forename: M
authors.initials: M
authors.lastname: Müller-Gerbl
authors.forename: M
authors.initials: M
authors.lastname: Raschke
authors.forename: K
authors.initials: K
authors.lastname: Herfeldt
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D001696:Biomechanical Phenomena; D007593:Joint Instability / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D007718:Knee Injuries / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D016059:Range of Motion, Articular / Q000502:physiology; D012756:Sheep; D013708:Tendon Injuries / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D013710:Tendons / Q000473:pathology / Q000503:physiopathology; D014945:Wound Healing / Q000502:physiology
vernacular_title: Läsionen des Popliteus-Systems und ihre Bedeutung für die Stabilität des Kniegelenkes.