A novel biomimetic material for engineering postsurgical adhesion using the injured digital flexor tendon-synovial complex as an in vivo model.
BACKGROUND
Many surgical procedures are complicated by adhesions. These restrictive fibrotic bands form between normally separate gliding tissue layers, potentially impairing function. The authors tested the adhesion-modifying effect of a novel fibronectin-derived biomimetic biomaterial in a tendon-synovial complex injury model.


METHODS
The deep flexor tendons of digits 2 and 4 in the right forepaw of 15 New Zealand White rabbits were subjected to 5-mm-long partial tenotomies. Animals were randomized to receive biomaterial tubes enveloping the tendon injuries or left untreated. Digits, amputated at 2 weeks, were randomized to mechanical pullout assessments of adhesion strength or to quantitative histologic cellularity and immunohistochemical proliferation (Ki67) assessments.


RESULTS
The mean peak pullout force required to break the adhesions was reduced from 7.70 N (n = 6) in untreated digits to 0.31 N (n = 7) in biomaterial-treated digits (p = 0.001). The mean structural stiffness of the adhesions was also significantly reduced (p = 0.001). Histologically, treated and untreated digits demonstrated an equal incidence of adhesions. The treated adhesions were 55 percent less cellular at their surface than the untreated injured controls (p = 0.003). Treated tendons were 8 percent more cellular (with equal numbers of proliferating cells) at their surface and significantly more cellular within their bulk than positive controls (p <or= 0.05).


CONCLUSIONS
This study suggests a significant reduction in the restrictive nature of postsurgical adhesions following treatment with the antiadhesive biomaterial without compromising tendon cellularity.
Branford
Olivier A
OA
Middlesex, Stanmore, and Manchester, United Kingdom From RAFT, Mount Vernon Hospital; University College London Tissue Repair and Engineering Center, Institute of Orthopedics; and University of Manchester Plastic and Reconstructive Surgery Research.
Mudera
Vivek
V
Brown
Robert A
RA
McGrouther
Duncan A
DA
Grobbelaar
Adriaan O
AO
D000818:Animals; D040761:Biomimetic Materials; D004195:Disease Models, Animal; D005353:Fibronectins; D005552:Forelimb; D019637:Orthopedic Procedures / Q000009:adverse effects; D011817:Rabbits; D013708:Tendon Injuries / Q000150:complications / Q000503:physiopathology*; D013710:Tendons / Q000601:surgery*; D013718:Tensile Strength; D000267:Tissue Adhesions / Q000209:etiology / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*
D005353:Fibronectins