A Preliminary Evaluation of a Hydro-cast Trans-femoral Socket, a Proof of Concept

This study reports on a research project that has utilised, for the first time, a Hydro-casting (HC) technique to create a prosthetic socket for a person with trans-femoral amputation. Outcome measurements of the HC socket were compared with a socket and prosthesis produced by conventional ischial containment (IC) technique. Comparisons were based on differences in (a) stump-socket interface pressures during gait, (b) whole body gait kinetics and kinematics (c) femoral movement within the stump tissues relative to the socket during gait. These observations provided a snapshot of the biomechanical environment of the stump and socket interface and assess the feasibility of using these outcome measurements to highlight differences between the two socket designs. This study demonstrated that it is feasible to use the HC approach to produce a prosthesis that is acceptable to both user and clinician. Results showed similarities between interface pressures, kinetic and kinematic data for both socket designs. The use of ultrasound to detect femoral motion identified that the conventional design paradigm, claiming to stabilise the motion of the femur, may not actually achieve this goal. Additional research is required with larger population of people with a trans-femoral amputation to assess the long term impact of this novel approach.