Absorbable sutures in tendon repair. A comparison of PDS with prolene in rabbit tendon repair

The risks of foreign implantation may be avoided in tendon repair by the use of absorbable sutures, for example polydioxanone. In this study, the in vivo tensile strength half-life of 4/0 polydioxanone was found to be approximately 4 weeks. Using a rabbit model, we compared polydioxanone tendon repairs with polypropylene tendon repairs. Unilateral flexor digitorum longus repairs were performed on 46 rabbits using either polydioxanone or polypropylene. Tendons were harvested at 3 days, 2 weeks and 4 weeks and the tensile breaking strengths were obtained. 30 intact rabbit flexor digitorum longus tendons and 20 freshly repaired tendons were also tested. By 4 weeks, the repair strength had increased eight-fold from approximately 20 N to 166 N. The sutures made little contribution to the overall strength of a 4-week-old repair. There was no significant difference between polydioxanone and polypropylene repairs at any stage. These results show that polydioxanone repairs were as strong as polypropylene during the first critical weeks of tendon healing.