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The work focuses on polymeric cartilage/bone pins (pegs) that were manufactured and tested to assess their application in meniscus injuries. The bone pins measuring 1,2 and 4 mm in diameter were produced from certified resorbable PLDLA by means of hot pressing (at 126oC). In order to establish the material characteristics, tests of mechanical properties, structural testing and stability tests were performed in vitro (an immersion medium: water/PBS buffer). It was established that after three months of incubation the initial implant’s bending strength (120 MPa) decreased by 35%, whereas its tensile strength (52 Pa) weakened by 60%. The degree of degradation did not affect the pH of the immersion fluid. The observed physical changes of the implant, such as: the mass decrease, the change of shape, the increase of crystallinity (DSC/TG), the number of polymer terminal groups (-OH, -COOH), proved the advanced degradation process of PLDLA pins. Implants of particular behaviour were inoculated into the tibia of a New Zealand rabbit. In vivo tests were conducted to confirm the changes observed in vitro. Monitoring of the degradation process was performed after three months following the implantation by means of control X-ray and computed microtomography (μCT).
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