The effects of fibroblast growth factor-2 on rotator cuff reconstruction with acellular dermal matrix grafts.
OBJECTIVE
Our purpose was to determine whether the local application of fibroblast growth factor (FGF) 2 accelerates regeneration and remodeling of rotator cuff tendon defects reconstructed with acellular dermal matrix (ADM) grafts in rats.


METHODS
Thirty adult male Sprague-Dawley rats were divided into equal groups undergoing FGF-treated and FGF-untreated repairs. All rats underwent placement of an ADM graft for the supraspinatus defect (3 x 5 mm). FGF-2 (100 microg/kg) in a fibrin sealant was applied to both shoulders in the FGF-treated group, whereas only fibrin sealant was applied in untreated group. At 2, 6, and 12 weeks after surgery, 5 rats (10 shoulders) in each group were sacrificed for histologic analysis (3 shoulders) and biomechanical testing (7 shoulders). The controls were 5 unoperated rats (3 histologic and 7 biomechanical control specimens).


RESULTS
Unoperated control tendons inserted into the bone by direct insertion; there was a zone of fibrocartilage between the tendon and bone. At 2 weeks, the FGF-treated group had tendon maturing scores similar to those in the untreated group (P > .05). At 6 and 12 weeks, the FGF-treated group had significantly higher scores (P < .05). At 2 weeks, specimens in both the treated and untreated groups exhibited similar strength; the ultimate tensile failure load was 6.0 +/- 4.0 N and 5.8 +/- 2.0 N, respectively (P > .05). At 6 weeks, the FGF-treated specimens were stronger, with an ultimate tensile failure load of 10.2 +/- 3.1 N compared with 7.2 +/- 2.2 N in the untreated group (P = .02). At 12 weeks, the FGF-treated specimens were stronger, with an ultimate tensile failure load of 15.9 +/- 1.6 N compared with 13.2 +/- 2.0 N in the untreated group (P = .0072), and there were no significant differences in strength compared with the controls (17.8 +/- 2.6 N) (P > .05).


CONCLUSIONS
The remodeling of ADM grafts placed in rat rotator cuff tendon defects was accelerated by the local administration of FGF-2.


CONCLUSIONS
The application of FGF-2 may result in improved histologic characteristics and biomechanical strength in ADM graft constructs in humans.
Ide
Junji
J
Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan. ide@kumamoto-u.ac.jp
Kikukawa
Kenshi
K
Hirose
Jun
J
Iyama
Ken-ichi
K
Sakamoto
Hidetoshi
H
Mizuta
Hiroshi
H
D000818:Animals; D001696:Biomechanical Phenomena; D004353:Drug Evaluation, Preclinical; D015718:Fibrin Tissue Adhesive; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D051445:Fibrocartilage / Q000473:pathology; D020007:Implants, Experimental; D008297:Male; D008422:Materials Testing; D018482:Muscle, Skeletal / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration; D017006:Rotator Cuff / Q000502:physiology / Q000601:surgery*; D054457:Tissue Scaffolds; D014945:Wound Healing
D015718:Fibrin Tissue Adhesive; D016222:Fibroblast Growth Factor 2