title: Quantitative analysis of attachment of the labrum to the glenoid fossa: a cadaveric study.
abstract: OBJECTIVE
  This study investigated the direct and continuous attachment of the labrum to the glenoid fossa, including the fibrocartilaginous tissue, using image-analysis software and histology.
  
  
  METHODS
  Twenty-six cadaveric shoulders (11 male, 15 female; mean age 80.1 years; age range 36-103 years) were used. The glenoid of each specimen was divided into six pie-slice-shaped pieces from the center perpendicular to the articular surface by radial incisions at the 2, 4, 6, 8, 10, and 12 o'clock positions. The general distribution of the labrum, including the fibrocartilage, was assessed in hematoxylin and eosin-, Safranin O- and Azan-Mallory-stained sections. The continuous length of attachment of the labrum to the glenoid was measured using image-analysis software. The width of attachment to the articular surface of the glenoid was assessed in each position.
  
  
  RESULTS
  The labrum attached to both the articular surface and the neck of the glenoid in all shoulders (100 %) in the 4 and 6 o'clock positions. The mean length of the entire attachment to the glenoid was 4.6 mm (range 3.2-6.1 mm). The width of attachment from the bony edge of the glenoid to the edge of the labrum on the articular surface ranged from 0 to 4.3 mm. The length of the entire attachment of the labrum was shortest in the 2 o'clock position (p = 0.229). Additionally, the length of the entire attachment of the labrum was longest in the 4 o'clock position. The width of attachment to the articular surface of the glenoid was greatest in the 4 o'clock position (p < 0.01).
  
  
  CONCLUSIONS
  In the 4 and 6 o'clock positions, the labrum attached to both the articular surface and neck of the glenoid in all of the shoulders (100 %). The length of the entire attachment to the labrum, including the fibrocartilage, was shortest in the 2 o'clock position. The width of attachment to the articular surface of the glenoid was greatest in the 4 o'clock position (p < 0.01).
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan. hide-g@fj8.so-net.ne.jp.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Goto
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nozaki
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishimori
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Takenaga
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Murase
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nagaya
authors.affiliation: Department of Arthroplastic Medicine, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Iguchi
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Nagoya Sports Clinic, Nagoya, Japan.
authors.forename: Katsumasa
authors.initials: K
authors.lastname: Sugimoto
authors.affiliation: Department of Public Health, Aichi Medical University, Nagakute, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishiyama
authors.affiliation: Department of Orthopedic Surgery, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8601, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Otsuka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D051445:Fibrocartilage / Q000166:cytology; D061165:Glenoid Cavity / Q000033:anatomy & histology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012540:Scapula / Q000033:anatomy & histology*; D012785:Shoulder Joint / Q000033:anatomy & histology*