title: The hamstring muscle complex.
abstract: OBJECTIVE
  The anatomical appearance of the hamstring muscle complex was studied to provide hypotheses for the hamstring injury pattern and to provide reference values of origin dimensions, muscle length, tendon length, musculotendinous junction (MTJ) length as well as width and length of a tendinous inscription in the semitendinosus muscle known as the raphe.
  
  
  METHODS
  Fifty-six hamstring muscle groups were dissected in prone position from 29 human cadaveric specimens with a median age of 71.5 (range 45-98).
  
  
  RESULTS
  Data pertaining to origin dimensions, muscle length, tendon length, MTJ length and length as well as width of the raphe were collected. Besides these data, we also encountered interesting findings that might lead to a better understanding of the hamstring injury pattern. These include overlapping proximal and distal tendons of both the long head of the biceps femoris muscle and the semimembranosus muscle (SM), a twist in the proximal SM tendon and a tendinous inscription (raphe) in the semitendinosus muscle present in 96 % of specimens.
  
  
  CONCLUSIONS
  No obvious hypothesis can be provided purely based on either muscle length, tendon length or MTJ length. However, it is possible that overlapping proximal and distal tendons as well as muscle architecture leading to a resultant force not in line with the tendon predispose to muscle injury, whereas the presence of a raphe might plays a role in protecting the muscle against gross injury. Apart from these architectural characteristics that may contribute to a better understanding of the hamstring injury pattern, the provided reference values complement current knowledge on surgically relevant hamstring anatomy.
  
  
  METHODS
  IV.
authors.affiliation: Department of Orthopaedic Surgery, Academic Medical Center, University of Amsterdam, PO Box 22700, 1100 DE, Amsterdam, The Netherlands, a.d.vandermade@amc.uva.nl.
authors.forename: A D
authors.initials: AD
authors.lastname: van der Made
authors.forename: T
authors.initials: T
authors.lastname: Wieldraaijer
authors.forename: G M
authors.initials: GM
authors.lastname: Kerkhoffs
authors.forename: R P
authors.initials: RP
authors.lastname: Kleipool
authors.forename: L
authors.initials: L
authors.lastname: Engebretsen
authors.forename: C N
authors.initials: CN
authors.lastname: van Dijk
authors.forename: P
authors.initials: P
authors.lastname: Golanó
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000293:injuries / Q000502:physiology*; D012015:Reference Standards; D013710:Tendons / Q000033:anatomy & histology / Q000502:physiology; D013848:Thigh