PURPOSE: To perform quantitative evaluation of lower-extremity prosthesis fit by using spiral computed tomography (CT). MATERIALS AND METHODS: Two spiral CT scans were obtained at each of two different sessions in seven adult patients who had undergone amputation below the knee. A rigid- body transformation of the tibia was computed and used to align paired (intra- and intersession) spiral CT data sets for each individual in a common coordinate system. Paired scans in each individual were compared to assess registration and precision of soft-tissue change measurement. Clinical prosthesis fit evaluation was demonstrated in an adult amputee volunteer who underwent CT evaluation while wearing two different prostheses. RESULTS: In the seven patients examined, more than 90% of the measured soft-tissue volume displacements between sessions could be explained as true differences. Precision error of soft-tissue volume change was approximately 13 cm3, or approximately 1% error relative to the mean volume. Volumetric changes due to different prostheses were substantially larger than the random error. CONCLUSION: Registration of CT volumetric data sets to quantify residual- limb soft-tissue envelope change in lower-limb prosthetics is precise and can be used to detect the effect of prosthesis shape alterations.
- Computed tomography (CT), helical
- Computed tomography (CT), image processing
- Computed tomography (CT), three-dimensional
- Computed tomography (CT), utilization
- Stents and prostheses