Vibroacoustography for the assessment of total hip arthroplasty

• Main Authors: Hermes A.S. Kamimura, Liao Wang, Antonio A.O. Carneiro, Randall R. Kinnick, Kai-Nan An, Mostafa Fatemi
• Format: Article
• Language: English
• Published: Faculdade de Medicina / USP 2013-04-01
• Series: Clinics
• Subjects: Arthroplasty; 3D Imaging; Vibroacoustography
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1807-59322013000400463
• ISSN: 1807-5932; 1980-5322

OBJECTIVES: This paper proposes imaging with 3-dimensional vibroacoustography for postoperatively assessing the uncovered cup area after total hip arthroplasty as a quantitative criterion to evaluate implant fixation. METHODS: A phantom with a bone-like structure covered by a tissue-mimicking material was used to simulate a total hip arthroplasty case. Vibroacoustography images of the uncovered cup region were generated using a two-element confocal ultrasound transducer and a hydrophone inside a water tank. Topological correction based on the geometry of the implant was performed to generate a 3-dimensional representation of the vibroacoustography image and to accurately evaluate the surface. The 3-dimensional area obtained by the vibroacoustography approach was compared to the area evaluated by a 3-dimensional motion capture system. RESULTS: The vibroacoustography technique provided high-resolution, high-contrast, and speckle-free images with less sensitivity to the beam incidence. Using a 3-dimensional-topology correction of the image, we accurately estimated the uncovered area of the implant with a relative error of 8.1% in comparison with the motion capture system measurements. CONCLUSION: Measurement of the cup coverage after total hip arthroplasty has not been well established; however, the covered surface area of the acetabular component is one of the most important prognostic factors. The preliminary results of this study show that vibroacoustography is a 3-dimensional approach that can be used to postoperatively evaluate total hip arthroplasty. The favorable results also provide an impetus for exploring vibroacoustography in other bone or implant surface imaging applications.