University of Twente Student Theses


A Novel 3D joint space quantification method in patients with osteoarthritis in the knee

Jansen, Mylène P. (2017) A Novel 3D joint space quantification method in patients with osteoarthritis in the knee.

[img] PDF
Abstract:Introduction: In patients with knee osteoarthritis, cartilage loss causes a joint space width (JSW) decrease between the femur and tibia, which can be measured to quantify the disease progression or the effects of treatments like high tibial osteotomy (HTO) and knee joint distraction (KJD). This is currently done using radiographs, but possible alternatives to give insight in the JSW distribution throughout the joint are CT and MRI, 3D imaging techniques for which a measuring method must be developed and validated. Since CT and MRI images are taken non-weight-bearing with an extended leg, as opposed to weight-bearing, semi-flexed radiographs, the effects of weight-bearing and flexion on the knee joint space should be investigated. Materials & Methods: Forty patients treated for knee OA (20 KJD, 20 HTO) were included. Radiographic outcomes and clinical characteristics were evaluated and CT and MRI scans were performed at baseline, one-year, and two-year follow-up. The JSW was measured on the radiographs and a 3D measurement method was developed to quantify the joint space in CT and MRI images. This semi-automatic method segments bone and generates heat maps and histograms to provide more insight in the joint space distribution. The JSW measurements were compared between imaging techniques and two-year changes were compared with clinical parameters. In an additional MRI study, four different MRI scans were performed on healthy volunteers: a weight-bearing scan with extended and flexed leg and a non-weight-bearing scan with extended and flexed leg. Qualitative inspection of heat maps was performed to gain insight in JSW distribution changes. Results: Correlations between radiographic and CT JSW were significant and strong while correlations of two-year JSW changes were not. Radiographic measurements agreed with two-year clinical parameter change better than CT measurements did. The MRI study showed a shift of smaller joint space distances to the posterior side when flexing and more small distances when weight-bearing. Discussion & Conclusion: The developed semi-automatic 3D JSW measurement method can quantify the 3D joint with minimal user input and visualize the joint space distribution throughout the joint. The weak two-year change correlation of CT JSW measurements with radiographs and clinical parameters cannot be directly explained from the available data, but joint space changes observed in the MRI study with healthy volunteers indicate that differences in weight-bearing and knee flexion between the imaging methods could be the key to explaining the found differences. Therefore, additional MRI research with OA patients is necessary.
Item Type:Essay (Master)
Faculty:TNW: Science and Technology
Subject:44 medicine, 50 technical science in general
Programme:Technical Medicine MSc (60033)
Link to this item:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page