A 3D-printed phantom twin and multi-transducer holder for dynamic anatomical ultrasonography of the lower limb

We aim to improve the residuum health of individuals suffering from lower-limb loss through ‘digital twin’ computational simulations for the creation of optimized 3D-printed prosthetic attachments. Our objective is to utilize 4D tracking data of various tissue interfaces as a primary input into the digital twin. Dynamic anatomical ultrasonography (DAU) is a novel technique in which synchronized individual transducers are positioned at known locations utilizing a 3D-printed holder. Pulse-echo ultrasound data are recorded and subsequently analyzed, providing plots of tissue interface depths versus recording time. For the scientific validation of the DAU technique, a bespoke 3D-printed phantom twin has been created incorporating replica compartments of soft-tissue interfaces and bone tissue of a healthy thigh. To demonstrate its utility, a preliminary experiment was performed in which the phantom twin was positioned within the DAU device and the replica bone manually traversed randomly; subsequent DAU analysis provided a plot of interface depth versus recording time.