title: A cadaveric model for ligamentum teres function: a pilot study.
abstract: OBJECTIVE
  Despite the prevalence and clinical consequences of ligamentum teres pathology, its function is poorly understood. The purpose of this study was to help define the role the ligamentum teres may have in hip joint stabilization and determine whether a ball and string model could be used to describe the function of the ligamentum teres.
  
  
  METHODS
  Eight embalmed cadavers were dissected to remove all soft tissue from around the hip, leaving only the ligamentum teres intact. Available hip abduction, adduction, medial rotation, and lateral rotation range of motion were measured for three repeated trials. The position of the ligamentum teres in relation to the femoral head was recorded at the endpoint position of these movements.
  
  
  RESULTS
  An endpoint position as limited by the ligamentum teres for abduction, medial rotation, and lateral rotation was identified at a mean of 73°(SD 11°), 64°(SD 11°), and 58°(SD 10°), respectively. Hip adduction was limited by bony contact and therefore was not measured. The ligamentum teres wrapped around the femoral head to prevent inferior, posterior, and anterior subluxation with abduction, medial rotation, and lateral rotation, respectively. Repeated measures ANOVA indicated no significant difference in endpoint position based on trial number for the three movements (n.s.).
  
  
  CONCLUSIONS
  The ligamentum teres consistently tightened to limit hip abduction, medial rotation, and lateral rotation. These results support a ball and string model for the femoral head and ligamentum teres. This information could be important for those with hip instability and ligamentum teres pathology.
authors.affiliation: Department of Physical Therapy, Duquesne University, 114 Rangos School of Health Sciences, Pittsburgh, PA 15282, USA. martinr280@duq.edu
authors.forename: RobRoy L
authors.initials: RL
authors.lastname: Martin
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Kivlan
authors.forename: F Richard
authors.initials: FR
authors.lastname: Clemente
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D008023:Ligaments, Articular / Q000502:physiology*; D008297:Male; D010865:Pilot Projects; D016059:Range of Motion, Articular / Q000502:physiology