Pathophysiology analysis of late infections in artificial joint implants

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K18531
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56020:Orthopedics-related
• Research Institution: Shinshu University
• Principal Investigator: Kamanaka Takayuki 信州大学, 医学部附属病院, 助教(診療) (30791884)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 人工関節 / 晩期感染

Outline of Final Research Achievements

In cell experiments, RAW cells, V79 cells, and MC cells were used to confirm that there was no difference in cell proliferation among various metals. FeCl3 proliferated significantly more in V79 than in other cells, but in other metals there was generally no significant difference in proliferation between cells. The metals that showed little growth in any of the cells were Pt alloys, Cr alloys, Ni alloys, Co alloys, and Pd alloys. Ti alloys often used in orthopedic surgery contain Ni and may inhibit cell proliferation.
In addition, metal particles were not detected in the soft tissue and synovial fluid around the implant collected from the case of revision surgery due to infection after artificial joint replacement, and evaluation could not be performed.

Free Research Field

脊椎外科

Academic Significance and Societal Importance of the Research Achievements

高齢化が進む近年、変形性膝関節症や変形性股関節症により人工関節置換術を受ける患者が増えている。人工関節置換術の合併症には手術部の感染があるが、術後数か月経過して起こる晩期感染症がある。晩期感染症患者のインプラントは緩みが生じていることが大半であるが起因菌が検出されないことも多い。インプラントから漏出する金属粒子が細胞毒性を起こしている可能性がある。細胞毒性を生じにくい金属を使用したインプラントを使うことで人工関節置換術後の晩期感染症を減らせる可能性がある。