Limits...
Short Term Evaluation of an Anatomically Shaped Polycarbonate Urethane Total Meniscus Replacement in a Goat Model.

Vrancken AC, Madej W, Hannink G, Verdonschot N, van Tienen TG, Buma P - PLoS ONE (2015)

Bottom Line: No signs of PCU wear were found and the implant did not induce an inflammatory response in the knee joint.This study demonstrates that the novel, anatomically shaped PCU total meniscal replacement is biocompatible and resistant to three months of physiological loading.Evidently, redesigning the fixation method is necessary.

View Article: PubMed Central - PubMed

Affiliation: Radboud University Medical Center, Radboud Institute for Health Sciences, Orthopaedic Research Lab, Nijmegen, The Netherlands.

ABSTRACT

Purpose: Since the treatment options for symptomatic total meniscectomy patients are still limited, an anatomically shaped, polycarbonate urethane (PCU), total meniscus replacement was developed. This study evaluates the in vivo performance of the implant in a goat model, with a specific focus on the implant location in the joint, geometrical integrity of the implant and the effect of the implant on synovial membrane and articular cartilage histopathological condition.

Methods: The right medial meniscus of seven Saanen goats was replaced by the implant. Sham surgery (transection of the MCL, arthrotomy and MCL suturing) was performed in six animals. The contralateral knee joints of both groups served as control groups. After three months follow-up the following aspects of implant performance were evaluated: implant position, implant deformation and the histopathological condition of the synovium and cartilage.

Results: Implant geometry was well maintained during the three month implantation period. No signs of PCU wear were found and the implant did not induce an inflammatory response in the knee joint. In all animals, implant fixation was compromised due to suture breakage, wear or elongation, likely causing the increase in extrusion observed in the implant group. Both the femoral cartilage and tibial cartilage in direct contact with the implant showed increased damage compared to the sham and sham-control groups.

Conclusion: This study demonstrates that the novel, anatomically shaped PCU total meniscal replacement is biocompatible and resistant to three months of physiological loading. Failure of the fixation sutures may have increased implant mobility, which probably induced implant extrusion and potentially stimulated cartilage degeneration. Evidently, redesigning the fixation method is necessary. Future animal studies should evaluate the improved fixation method and compare implant performance to current treatment standards, such as allografts.

No MeSH data available.


Related in: MedlinePlus

Goat version of the anatomically shaped, polycarbonate urethane (PCU) total medial meniscus replacement.a) Implant including the sutures for fixation to the tibia plateau. b) Direct comparison between the goat PCU implant and a native medial meniscus that was replaced by the implant.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4507942&req=5

pone.0133138.g001: Goat version of the anatomically shaped, polycarbonate urethane (PCU) total medial meniscus replacement.a) Implant including the sutures for fixation to the tibia plateau. b) Direct comparison between the goat PCU implant and a native medial meniscus that was replaced by the implant.

Mentions: Implant geometry was derived from an excised medial meniscus of a female Dutch milk goat (Capra Hircus Sana) that was soaked in Omnipaque Iohexol (300 mg I/mL, GE Healthcare, Inc., Princeton, NJ, USA) for 2 hours and subsequently microCT scanned in air (μCT 40, Scanco Medical AG, Brüttisellen, Switzerland). The scans were taken using the following settings: 70 kVp, 114 μA, 300 ms exposure time, 264 slices and 36x36x36 μm resolution. A 3D model of this meniscus was created and the meniscal horns were extended five millimeters to allow some flexibility in adjusting the width of the implant to that of the native meniscus and for suture fixation of the implant to the tibia plateau. Polycarbonate urethane (PCU, Bionate II 80A, DSM Biomedical, Berkeley, CA) implants were subsequently produced by injection molding (Fig 1a). All implants were sterilized by ethylene oxide gas (Synergy Health, Venlo, the Netherlands).


Short Term Evaluation of an Anatomically Shaped Polycarbonate Urethane Total Meniscus Replacement in a Goat Model.

Vrancken AC, Madej W, Hannink G, Verdonschot N, van Tienen TG, Buma P - PLoS ONE (2015)

Goat version of the anatomically shaped, polycarbonate urethane (PCU) total medial meniscus replacement.a) Implant including the sutures for fixation to the tibia plateau. b) Direct comparison between the goat PCU implant and a native medial meniscus that was replaced by the implant.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507942&req=5

pone.0133138.g001: Goat version of the anatomically shaped, polycarbonate urethane (PCU) total medial meniscus replacement.a) Implant including the sutures for fixation to the tibia plateau. b) Direct comparison between the goat PCU implant and a native medial meniscus that was replaced by the implant.
Mentions: Implant geometry was derived from an excised medial meniscus of a female Dutch milk goat (Capra Hircus Sana) that was soaked in Omnipaque Iohexol (300 mg I/mL, GE Healthcare, Inc., Princeton, NJ, USA) for 2 hours and subsequently microCT scanned in air (μCT 40, Scanco Medical AG, Brüttisellen, Switzerland). The scans were taken using the following settings: 70 kVp, 114 μA, 300 ms exposure time, 264 slices and 36x36x36 μm resolution. A 3D model of this meniscus was created and the meniscal horns were extended five millimeters to allow some flexibility in adjusting the width of the implant to that of the native meniscus and for suture fixation of the implant to the tibia plateau. Polycarbonate urethane (PCU, Bionate II 80A, DSM Biomedical, Berkeley, CA) implants were subsequently produced by injection molding (Fig 1a). All implants were sterilized by ethylene oxide gas (Synergy Health, Venlo, the Netherlands).

Bottom Line: No signs of PCU wear were found and the implant did not induce an inflammatory response in the knee joint.This study demonstrates that the novel, anatomically shaped PCU total meniscal replacement is biocompatible and resistant to three months of physiological loading.Evidently, redesigning the fixation method is necessary.

View Article: PubMed Central - PubMed

Affiliation: Radboud University Medical Center, Radboud Institute for Health Sciences, Orthopaedic Research Lab, Nijmegen, The Netherlands.

ABSTRACT

Purpose: Since the treatment options for symptomatic total meniscectomy patients are still limited, an anatomically shaped, polycarbonate urethane (PCU), total meniscus replacement was developed. This study evaluates the in vivo performance of the implant in a goat model, with a specific focus on the implant location in the joint, geometrical integrity of the implant and the effect of the implant on synovial membrane and articular cartilage histopathological condition.

Methods: The right medial meniscus of seven Saanen goats was replaced by the implant. Sham surgery (transection of the MCL, arthrotomy and MCL suturing) was performed in six animals. The contralateral knee joints of both groups served as control groups. After three months follow-up the following aspects of implant performance were evaluated: implant position, implant deformation and the histopathological condition of the synovium and cartilage.

Results: Implant geometry was well maintained during the three month implantation period. No signs of PCU wear were found and the implant did not induce an inflammatory response in the knee joint. In all animals, implant fixation was compromised due to suture breakage, wear or elongation, likely causing the increase in extrusion observed in the implant group. Both the femoral cartilage and tibial cartilage in direct contact with the implant showed increased damage compared to the sham and sham-control groups.

Conclusion: This study demonstrates that the novel, anatomically shaped PCU total meniscal replacement is biocompatible and resistant to three months of physiological loading. Failure of the fixation sutures may have increased implant mobility, which probably induced implant extrusion and potentially stimulated cartilage degeneration. Evidently, redesigning the fixation method is necessary. Future animal studies should evaluate the improved fixation method and compare implant performance to current treatment standards, such as allografts.

No MeSH data available.


Related in: MedlinePlus