title: Histological and molecular characterization of the femoral attachment of the human ligamentum capitis femoris.
abstract: The ligamentum capitis femoris (LCF) has increased in clinical significance through the development of hip arthroscopy. The histological pathologies and molecular composition of the femoral attachment of the LCF and the degeneration caused by LCF disruption were investigated in the human hip joint. Twenty-four LCFs were retrieved at surgery for femoral neck fracture (age range: 63-87 years). In the "intact" (i.e., intact throughout its length, n = 12) group, the attachment consisted of rich fibrocartilage. Fibrocartilage cells were present in the midsubstance. In contrast, the construction of the attachment in the "disrupted" (i.e., ligament no longer attached to the femoral head, n = 12) group had disappeared. The attachment in the disrupted group was not labeled for type II collagen or aggrecan, while that in the intact group was labeled for types I, II and III collagen, chondroitin 4-sulfate, chondroitin 6-sulfate, aggrecan, and versican. The percentage of single-stranded DNA-positive chondrocytes was significantly higher in the disrupted group than in the intact group. We conclude that the femoral attachment of the LCF has a characteristic fibrocartilaginous structure that is likely to adjust to the mechanical load, and suggest that its degeneration is advanced by disruption and should be regarded as a clinical pathology.
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Shinohara
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kumai
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Higashiyama
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Matsuda
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Nara, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Takakura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D053674:Aggrecans / Q000032:analysis; D019902:Chondrocytes / Q000737:chemistry; D002809:Chondroitin Sulfates / Q000032:analysis; D024042:Collagen Type I / Q000032:analysis; D024043:Collagen Type II / Q000032:analysis; D024061:Collagen Type III / Q000032:analysis; D004277:DNA, Single-Stranded / Q000032:analysis; D005260:Female; D005265:Femoral Neck Fractures / Q000601:surgery; D005270:Femur Head / Q000737:chemistry / Q000293:injuries / Q000473:pathology*; D051445:Fibrocartilage / Q000737:chemistry / Q000473:pathology; D006621:Hip Joint; D006801:Humans; D008297:Male; D008875:Middle Aged; D000069593:Round Ligament of Femur / Q000737:chemistry / Q000293:injuries / Q000473:pathology*
chemical_list: D053674:Aggrecans; D024042:Collagen Type I; D024043:Collagen Type II; D024061:Collagen Type III; D004277:DNA, Single-Stranded; D002809:Chondroitin Sulfates
keywords: enthesis; ligament rupture; stability; stress deprivation