title: Effects of corticosteroids and hyaluronic acid on torn rotator cuff tendons in vitro and in rats.
abstract: Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HA-treated tendons (p < 0.05), as well as PCNA(+) cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site.
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Gotoh
authors.affiliation: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University school of Medicine, Fukuoka, Japan.
authors.forename: Tomonoshin
authors.initials: T
authors.lastname: Kanazawa
authors.affiliation: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University school of Medicine, Fukuoka, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ohta
authors.affiliation: Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University school of Medicine, Fukuoka, Japan.
authors.forename: Keiichirou
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Honda
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ohzono
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Shimokobe
authors.affiliation: Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Mitsui
authors.affiliation: Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Shirachi
authors.affiliation: Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Okawa
authors.affiliation: Department of Orthopedic Surgery, Kurume University, Fukuoka, Japan.
authors.forename: Fujio
authors.initials: F
authors.lastname: Higuchi
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Shirahama
authors.affiliation: Department of Orthopedic Surgery, Kurume University Medical Center, Fukuoka, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Shiba
authors.affiliation: Cancer Vaccine Center, Kurume University, Fukuoka, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Matsueda
mesh_terms: D000305:Adrenal Cortex Hormones / Q000009:adverse effects*; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects* / Q000648:ultrastructure; D006801:Humans; D006820:Hyaluronic Acid / Q000009:adverse effects*; D007150:Immunohistochemistry; D008297:Male; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D017006:Rotator Cuff / Q000187:drug effects*; D000070636:Rotator Cuff Injuries; D016474:Weight-Bearing
chemical_list: D000305:Adrenal Cortex Hormones; D006820:Hyaluronic Acid
keywords: corticosteroids; hyaluronic acids; tendon; tendon fibroblast; totator cuff tears