Comparison of á priori alignment techniques for transtibial prostheses in the developing world - pilot study

The purpose of this study was to evaluate three alignment systems based on two alignment theories that can be utilized in the fabrication of monolimb prostheses that have acceptable alignment. A second goal was to assess the feasibility of technology transfer for providing prosthetic services to remote areas of landmine-affected countries.

Five prosthetists and five healthy transtibial amputees participated in the study. Each prosthetist was trained and then used each of the three systems to capture alignment measurements for one subject. Three monolimbs identified as X, Y and Z were fabricated for each subject and assessed during clinical static and dynamic gait conditions. Training materials and methods were also evaluated.

All three systems captured acceptable alignments fairly well, although the two systems that incorporated weight-bearing into the alignment process had slightly better outcomes. Each system has its own advantages in terms of ease of use, required equipment, and ease of technology transfer.

All three systems have the potential for application in outreach prosthetic services and warrant continued evaluation. Minor changes need to be incorporated into the alignment systems and procedures to make them easier to use and more effective.