A photoactivated nanofiber graft material for augmented Achilles tendon repair.
OBJECTIVE
Suture repair of Achilles tendon rupture can cause infection, inflammation and scarring, while prolonged immobilization promotes adhesions to surrounding tissues and joint stiffness. Early mobilization can reduce complications provided the repair is strong enough to resist re-rupture. We have developed a biocompatible, photoactivated tendon wrap from electrospun silk (ES) to provide additional strength to the repair that could permit early mobilization, and act as a barrier to adhesion formation.


METHODS
ES nanofiber mats were prepared by electrospinning. New Zealand white rabbits underwent surgical transection of the Achilles tendon and repair by: (a) SR: standard Kessler suture + epitendinous suture (5-0 vicryl). (b) ES/PTB: a single stay suture and a section of ES mat, stained with 0.1% Rose Bengal (RB), wrapped around the tendon and bonded with 532 nm light (0.3 W/cm(2) , 125 J/cm(2) ). (c) SR + ES/PTB: a combination of (a) and (b). Gross appearance, extent of adhesion formation and biomechanical properties of the repaired tendon were evaluated at Days 7, 14, or 28 post-operatively (n = 8 per group at each time point).


RESULTS
Ultimate stress (US) and Young's modulus (E) in the SR group were not significantly different from the ES/PTB group at Days 7 (US, P = 0.85; E, P = 1), 14 (US, P = 0.054; E, P = 1), and 28 (US, P = 0.198; E, P = 0.12) post-operatively. Adhesions were considerably greater in the SR group compared to the ES/PTB group at Days 7 (P = 0.002), 14 (P < 0.0001), and 28 (P < 0.0001). The combination approach of SR + ES/PTB gave the best outcomes in terms of E at 7 (P < 0.016) and 14 days (P < 0.016) and reduced adhesions compared to SR at 7 (P < 0.0001) and 14 days (P < 0.0001), the latter suggesting a barrier function for the photobonded ES wrap.


CONCLUSIONS
Photochemical sealing of a ES mat around the tendon repair site provides considerable benefit in Achilles tendon repair. Lasers Surg. Med. 44: 645-652, 2012. © 2012 Wiley Periodicals, Inc.
Department of Burns and Plastic Surgery, No. 3 People's Hospital, and Institute of Traumatic Medicine; School of Medicine, Shanghai Jiao Tong University, Shanghai 201900, P.R. China.
Tao
T
Ni
Prabhu
P
Senthil-Kumar
Karen
K
Dubbin
Salvador D
SD
Aznar-Cervantes
Néha
N
Datta
Mark A
MA
Randolph
José L
JL
Cenis
Gregory C
GC
Rutledge
Irene E
IE
Kochevar
Robert W
RW
Redmond
D000125:Achilles Tendon / Q000293:injuries / Q000473:pathology / Q000601:surgery*; D000818:Animals; D001672:Biocompatible Materials; D005456:Fluorescent Dyes; D007834:Lasers; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D057139:Nanofibers; D055668:Photochemical Processes; D011817:Rabbits; D012395:Rose Bengal; D047011:Silk; D013537:Sutures; D013718:Tensile Strength; D000267:Tissue Adhesions / Q000473:pathology
D001672:Biocompatible Materials; D005456:Fluorescent Dyes; D047011:Silk; D012395:Rose Bengal