A Bioabsorbable Polymer for Collateral Ligament Repair in the Pig

Summary

A bioabsorbable internal fixation device of a poly-L-isomer of lactic acid (PLLA) was used to repair the proximal attachment of the medial femorotibial collateral ligament (MCL) in six miniature Yucatan pigs and compared with metal screw fixation in four pigs. Healing was evaluated by physical examination, gross dissection of surgical sites and histological evaluation of bone ligament interface. Chemical stress analysis of the tack was also evaluated.

The absorbable PLLA tack induced minimal tissue reaction and maintained sufficient apposition for healing of the MCL in the miniature Yucatan pigs. No postsurgical complications were noted in the experimental or control groups. All surgical implant procedures were considered successful in maintaining MCL apposition. This study suggests future potential for utilization of the PLLA tack for bioabsorbable implants in soft tissue or bone.

A bioabsorbable internal fixation device of a poly-L-isomer of lactic acid was used to repair the proximal attachment of the medial femorotibial collateral ligament in pigs, and compared with metal screw fixation. No postsurgical complications were noted in either group. All surgical implant procedures were successful. This study suggests future potential for utilization of the tack for bioabsorbable implants in soft tissue or bone.

Keywords

Bioabsorbable - lactic acid - collateral ligament

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