Abstract: Objective To study the design and fabrication of the sub-ischial compression/release stabilized (CRS) transfemoral prosthetic socket based on 3D reconstructed residual limb. Methods The magnetic resonance imaging (MRI) of a transfemoral amputee's residual limb was used for 3D construction. The base of the socket was constructed by the surface of the 3D geometry of residual limb in SolidWorks, and then the sketching and swept surface function was applied to create the compression and release structure. The CRS socket was analyzed by finite element method. The simulation was then validated experimentally. Results The transfemoral CRS socket was successfully constructed in SolidWorks and assembled with the residual limb for finite element modeling. The simulation results showed the residual limb pressure distribution over the CRS socket compression areas. The maximum residual limb pressure was predicted to be 218.5 kPa by the finite element model, and experimentally measured was 239 kPa. The maximum residual limb pressure was within the pain threshold and pain tolerance range, and the patient was satisfied with the socket. Conclusion This attempt of reconstructing residual limb MRI to design the CRS prosthetic socket provided another way to study the socket behavior in the prosthesis fitting process. The FEM-CAD method can improve the socket design and fitting process with computer simulation to reduce the trial on patients.

Key words: transfemoral amputation, prosthesis, socket, three-dimensional reconstruction, compression/release, finite element