A novel standardized algorithm using SPECT/CT evaluating unhappy patients after unicondylar knee arthroplasty– a combined analysis of tracer uptake distribution and component position

BMC Medical Imaging

Research Article

Patrick Stämpfli¹  Michael T Hirschmann¹  Basil Suter¹  Niklaus F Friederich¹  Enrique Testa¹  Praveen Konala²  Helmut Rasch³ 

[1] Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laifen), CH-4101, Bruderholz, Switzerland;Department of Radiology, Plymouth, UK;Institute for Radiology and Nuclear Medicine, Kantonsspital Baselland, CH-4101, Bruderholz, Switzerland;

关键词: Knee;    SPECT/CT;    SPECT-CT;    Unicondylar knee arthroplasty;    Component position;    Localization scheme;    3D-CT;    Unicompartmental knee replacement;    Bone;   

DOI  :  10.1186/s12880-015-0053-4

 received in 2014-10-30, accepted in 2015-03-04,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundThe introduction of a standardized SPECT/CT algorithm including a localization scheme, which allows accurate identification of specific patterns and thresholds of SPECT/CT tracer uptake, could lead to a better understanding of the bone remodeling and specific failure modes of unicondylar knee arthroplasty (UKA). The purpose of the present study was to introduce a novel standardized SPECT/CT algorithm for patients after UKA and evaluate its clinical applicability, usefulness and inter- and intra-observer reliability.MethodsTc-HDP-SPECT/CT images of consecutive patients (median age 65, range 48–84 years) with 21 knees after UKA were prospectively evaluated. The tracer activity on SPECT/CT was localized using a specific standardized UKA localization scheme. For tracer uptake analysis (intensity and anatomical distribution pattern) a 3D volumetric quantification method was used. The maximum intensity values were recorded for each anatomical area. In addition, ratios between the respective value in the measured area and the background tracer activity were calculated. The femoral and tibial component position (varus-valgus, flexion-extension, internal and external rotation) was determined in 3D-CT. The inter- and intraobserver reliability of the localization scheme, grading of the tracer activity and component measurements were determined by calculating the intraclass correlation coefficients (ICC).ResultsThe localization scheme, grading of the tracer activity and component measurements showed high inter- and intra-observer reliabilities for all regions (tibia, femur and patella). For measurement of component position there was strong agreement between the readings of the two observers; the ICC for the orientation of the femoral component was 0.73-1.00 (intra-observer reliability) and 0.91-1.00 (inter-observer reliability). The ICC for the orientation of the tibial component was 0.75-1.00 (intra-observer reliability) and 0.77-1.00 (inter-observer reliability).ConclusionsThe SPECT/CT algorithm presented combining the mechanical information on UKA component position, alignment and metabolic data is highly reliable and proved to be a valuable, consistent and useful tool for analysing postoperative knees after UKA. Using this standardized approach in clinical studies might be helpful in establishing the diagnosis in patients with pain after UKA.

【 授权许可】

Unknown   
© Suter et al.; licensee BioMed Central. 2015. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.