Use this URL to cite or link to this record in EThOS:
Title: Understanding why knee implants fail
Author: Cerquiglini, Arianna
ISNI:       0000 0004 8499 876X
Awarding Body: UCL (University College London)
Current Institution: University College London (University of London)
Date of Award: 2019
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Restricted access.
Access from Institution:
Total knee replacement (TKR) is a common intervention with an excellent survival rate; however, up to 20% of patients have reported poor outcomes, leading to revision. The overarching aim of this thesis is to better understand the complex mechanisms leading to knee implant failure, investigating the influence of both components' position and design features on implant performance in contemporary TKRs. Results from retrieval analysis are combined with clinical and patient imaging data, collected through collaborations with international high-volume revision surgeons. For the first time, implant position in all three anatomical planes were assessed using an innovative 3D computed tomography imaging technique and correlated with results from retrieval analysis. Tibial slope and axial rotation in malpositioned TKR showed to directly influence surface damage pattern in polyethylene tibial inserts. A new micro-CT based method for analysing polyethylene tibial inserts was developed and evaluated, in order to overcome the limitations of previous studies. This method was used to assess potential correlations with implant position in the coronal plane and SPECT/CT signal, an innovative imaging technique able to visualise the bone activity. Results showed that polyethylene deformation was influenced by both components' and overall positions and correlated with the in-vivo loading condition identified by the SPECT/CT signal pattern. This investigative approach was used in a retrieval comparative study to evaluate a current and controversial clinical problem. The Attune Knee System (DePuy) has been used in other 600,000 patients worldwide, showing good clinical outcome; however, serious concerns over the cement-tibial interface have been reported. Results revealed that changes in design features may influence the cement adhesion on tibial trays and the extent of polyethylene surface damage. Results from this thesis help to better understand the mechanism of failure in contemporary TKRs, showing the impact that both components' position and design have on implant performance.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available