Background: This report evaluates the effect of a suture loaded with basic fibroblast growth factor (bFGF) on acute rotator cuff healing in an ovine model.
Methods: Binding and release kinetics of bFGF on a hydroxyapatite coated Orthocord suture were tested in vitro. Ten mature female sheep were used and divided into two treatment groups in the in vivo study. In each of the 10 sheep, an infraspinatus tendon in one randomly selected shoulder was detached and then re-attached either by an Orthocord suture loaded with bFGF or a suture only (n=5/treatment). All sheep were euthanized at 6 weeks after surgery. Both operated and nonoperated shoulders were histologically evaluated.
Results: The in vitro study demonstrated that the bFGF was efficiently loaded on hydroxyapatite-coated Orthocord, and over 70% of the loaded bFGF remained on the suture after five passages through the infraspinatus tendon. Approximately 20–25% of the initially loaded bFGF was released in a sustained manner during a 6-week timeframe in vitro. In the in vivo study, the infraspinatus tendons for each group were significantly different from each other (P<0.0001) with the bFGF group (mean±SD, 1.6±0.1 cm) significantly thicker than the non-bFGF loaded group (1.0±0.1 cm) (P<0.0001), and both were thicker than the nonoperated controls (0.6±0.07 cm) (P<0.0001).
Conclusions: The technique using a suture material loaded with bFGF demonstrated that the diameter of the healed tendon increased. Histologic improvement of the healed tendon was not demonstrated in the current study.
Clinical Relevance: bFGF loaded on suture material may have a beneficial effect on tendon repair.
aComparative Orthopaedic Research Laboratory, School of Veterinary Medicine, University of Wisconsin-Madison
bDepartment of Orthopedics and Rehabilitation
cDepartment of Biomedical Engineering
dDepartment of Pharmacology, University of Wisconsin, Madison, WI
This study was funded by the Wallace H. Coulter Foundation Translational Research Partnership (#133-PRJ14CU).The authors declare no conflicts of interest.William L. Murphy and Mark D. Markel have contributed equally to this study.
Correspondence to Yan Lu, MD, Department of Medical Sciences, University of Wisconsin, 2015 Linden Drive, Madison, WI 53706 Tel: +608 265 7878; fax: +608-265-8020; e-mail: firstname.lastname@example.org