Prosthesis malignment can lead to acute and chronic health problems. Prosthetic alignment is traditionally set through physical exam and gait observation. Based on experience, these methods are often not optimal, thus, we began to use long leg anterior and posterior (AP) radiographs during the fitting process in order to obtain neutral alignment more accurately and efficiently. This study’s purpose was to quantify the effectiveness of using long leg AP radiographs, compared to traditional methods of fitting lower extremity prostheses. Radiographs obtained from lower extremity amputees between Sept 2009 and August 2010 were retrospectively reviewed. Long leg AP radiographs taken after the prosthesis had been fit based on traditional methods (baseline) were compared to long leg AP radiographs obtained after adjustments had been made based on radiographic parameters (post adjustment). Mechanical axis angular deviation (MAAD), distal displacement (DD) and leg length discrepancy (LLD) were measured. A qualitative assessment of baseline and post-adjustment long leg AP radiographs as performed to determine whether neutral alignment had been achieved (MAAD ≤ 1˚, LLD ≤ 10 mm). After prosthetic adjustments were made based on radiographic parameters, all measurements were closer to neutral and MAAD and DD were significantly decreased. Although the average final LLD decreased, it was not significant. This is the first study to document the benefits of using radiographic parameters to achieve a more neutral alignment in lower extremity prostheses. A larger sample size is needed to make more definitive conclusions of the efficacy of using long leg AP radiographs for amputee subgroups.
Abby Schultz, ’11
Major: Biochemistry and Molecular Biology, Art and Art History
Sponsor: Craig Tepper