[An extended CT scale technique for evaluating periprosthetic bone lesions - an in vitro study].
OBJECTIVE
In the present study the reduction of artifacts using an extended CT scale technique was examined in 5 vitallium and 5 titanium-aluminium-vanadium tumor prostheses.


METHODS
5 titanium-aluminium-vanadium and 5 vitallium distal femur Mutars(R) tumor prostheses (Mutars(R) - Modular Universal Tumor And Revision System) were implanted in 10 human femur specimens. 110 artifical drill hole lesions of 1 mm, 2 mm, 3 mm, 5 mm and 8 mm diameter were placed in the bone around the hexagonal stem of the tumor prosthesis and furthermore in the proximal part of the femur. All specimens were examined using conventional CT and an extended CT scale technique in a slice thickness of 3 mm.


RESULTS
In the proximal part of the femur all drill holes could be detected using 3 mm slices, no artefacts were observed. Along the hexagonal stem smooth lines arising from each hexagonal plane could be observed. This made it impossible to detect a 1 mm drill in 1 vitallium and in 1 titanium-aluminium-vanadium stem. There was no difference between the extended CT scale and conventional CT.


CONCLUSIONS
The extended CT scale did not significantly (p > 0.05, t-test) improve the imaging of artificial drill hole lesions along the hexagonal Mutras(R) stem.
Gosheger
G
G
Klinik und Poliklinik für Allgemeine Orthopädie der Westfälischen Wilhelms-Universität Münster. goshegg@uni-muenster.de
Ludwig
K
K
Hillmann
A
A
Meier
N
N
Boettner
F
F
Winkelmann
W
W
D000368:Aged; D000369:Aged, 80 and over; D000497:Alloys; D016477:Artifacts; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D005266:Femoral Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D011856:Radiographic Image Enhancement; D012680:Sensitivity and Specificity; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*; D014025:Titanium; D014057:Tomography, X-Ray Computed; D014800:Vitallium
D000497:Alloys; D014800:Vitallium; C031462:titanium alloy (TiAl6V4); D014025:Titanium