Optimization of surface modifications of extrasynovial tendon to improve its gliding ability in a canine model in vitro

Abstract

Previous studies have shown that the carboxyl groups in hyaluronic acid (HA) could be activated by 1-ethy 1-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS) to form intermediate O-acylisoureas, which can chemically bind to exposed amino groups on the tendon surface, leading to improved gliding ability. However, the optimal ratio and concentrations of the components in this chemical mixture were not investigated. The purpose of this study was to optimize the constituents of this tissue engineering approach to tendon surface modification, to reduce friction and improve durability. Peroneus longus (PL) tendons (n ¼ 40) were harvested from adult mongrel dogs along with the A2 pulley obtained from the ipsilateral hind paw. After the gliding resistance of the normal PL tendon was measured, the tendons were treated under varying concentrations of HA (0.5, 1, and 2%) and EDC/NHS (0.05, 0.25, and 1%) mixed with a 10% gelatin. Tendon friction was measured for 1000 cycles of simulated flexion/extension motion. Following testing, the residual HA on the tendon surface was evaluated by immunohistochemisty. The gliding resistance of the untreated PL tendons had a mean value of 0.087 AE 0.021 N. After surface treatment, there was no significant difference in friction due to HA concentration alone, but the concentration of EDC/NHS and the interaction between HA concentration and EDC/NHS concentration had a significant effect on friction. Regardless of HA concentration, the friction after 1000 cycles was significantly decreased in preparations which included a 1% concentration of EDC/ NHS. The tendons with lower gliding resistance presented a smoother surface on light microscopy and maintained more residual HA on the tendon surface. By varying the relative concentrations of HA, EDC, and NHS it is possible to optimize the effect of surface treatment on friction and durability in a canine extrasynovial tendon in vitro. ß

Compressive properties of cd-HA-gelatin modified intrasynovial tendon allograft in canine model in vivo

“…Because high gliding resistance causes more adhesions (Zhao et al, 2001a, 2001b) we tried to decrease the gliding resistance for extrasynovial tendon autografts. We found that tendon surface modification with chemically modified hyaluronic acid could improve grafted extrasynovial tendon gliding ability in vitro and in vivo (Momose et al, 2002; Sun et al, 2004; Taguchi et al, 2008; Tanaka et al, 2006, 2007; Yang et al, 2004; Zhao et al, 2006). In addition, we recently reported that this tendon surface treatment, combined with gelatin, significantly improved gliding ability of lyophilized tendon as well (Ikeda et al, 2010).…”

“…However, the gliding ability of intrasynovial tendons prepared by lyophilization, a common method of preservation, is significantly decreased (Ikeda et al, 2010). To increase the tendon gliding ability, surface modification with carbodiimide derivatized hyaluronic acid (cd-HA) has been well studied (Ikeda et al, 2010; Momose et al, 2002; Sun et al, 2004; Taguchi et al, 2008; Tanaka et al, 2006; Yang et al, 2004). This surface modification indeed has been recently reported to mitigate this adverse effect, leading to decreased postoperative adhesions (Zhao et al, 2010).…”

Repopulation of Intrasynovial Flexor Tendon Allograft with Bone Marrow Stromal Cells: AnEx VivoModel

“…33 We found that the increase in gliding resistance was reversed through surface modification with cd-HA-gelatin. The efficacy of this modification has been reported in both in vitro 33,48 and in vivo 39,49 models. Karabekmez and Zhao reported that surface modification with cd-HA decreased the adhesion formation without altering the cellularity in either the autologous extrasynovial tendon or the intrasynovial allograft in an in vivo canine model.…”

Effects of Stress Deprivation on Lubricin Synthesis and Gliding of Flexor Tendons in a Canine Model in Vivo

“…Second, we did not determine if wear was enhanced following a reduction in lubricin content. Our previous studies showed that flexor tendons could maintain an intact surface during up to 1000 cycles of repetitive motion 27,41 . This suggests that lubricin, a component of the flexor tendon surface, resists wear.…”