Radiographic parameters improve lower extremity prosthetic alignment

Abstract

Purpose The goal of prosthetic fitting is to provide comfort and functionality to the patient. It is thought that incorporating the use of standing anterior-posterior long leg radiographs (LLR) into the fitting of lower extremity prostheses will provide an objective guide when making adjustments, and be a better assessment of alignment. This study compares prosthetic alignment before and after radiography-guided adjustments. Method This retrospective study was performed at a multidisciplinary amputee clinic on patients with congenital and/or acquired limb deficiencies. Their prosthetic alignment was evaluated by LLR and adjusted as needed. Satisfactory alignment was defined as a mechanical axis angular deviation of B1°and a leg length discrepancy of B10 mm.Results A total of 45 unique prostheses from 24 subjects (10 female and 14 male) were included. Post-adjustment radiographs were obtained from 29 prostheses. After the initial prosthetic fitting, the probability of a satisfactory fit was 20.0 % (95 % CI 10.9-34.9 %). Following the baseline adjustment, the probability of a satisfactory fit improved to 53.3 % (95 % CI 37.5-70.9 %). After adjustment number 4, the probability of a satisfactory fit further improved to 76.7 % (95 % CI 41.9-98.0 %). There were also significant improvements in distal offset distance (p = 0.0040) and leg length discrepancy (p = 0.0206). The distal offset distance decreased by an average of 10.7 mm (95 % CI 3.6-17.8), and leg length discrepancy decreased by an average of 3.0 mm (95 % CI 00.48-5.5). Conclusions The addition of LLRs to existing fitting methods significantly improves prosthetic alignment and length.

Application and Evaluation of Lighthouse Technology for Precision Motion Capture

“…Socket reaction moments and ground reaction forces have been found to be some of the notable factors that indicate misalignment [9]. Other studies have established that radiographic parameters and gait or temporal parameters can also serve as important factors for guiding alignment [10] [11]. Hence, instead of using a system that relies on parameters such as visual inspection, experience, and skill of the prosthetist, more pronounced and effective methods can be devised to capture motion and align a prosthesis.…”

A systematic review of methods used to assist transtibial prosthetic alignment decision-making

“…The rest of the studies [20][21][22] aligned the prosthesis at the bench before the walking trials, and 1 study did not state. 24 In the primary studies, although 10 m of self-selected walking speed for amputees to adapt alignment changes between trials was considered, adaptation time for 19 studies was not reported. The rest of the studies offered an adaptation time ranging from 5 to 30 min, 25,26,29 one study checked the prosthetic alignment after 1 month, 21 and another followed up monthly for 2 years.…”

Scoping review to evaluate existing measurement parameters and clinical outcomes of transtibial prosthetic alignment and socket fit

“…17,18,[28][29][30]37,42,45,47,50,54,62,68,70,78,79 Of the studies that relied on the prosthetist's judgment, eight included supplemental verbal or written patient report. 26,39,43,49,52,56,58,69 No study solely depended on patient report, contrary to assessments of socket fit. All the studies assessing alignment parameter with patient feedback included a second quantitative clinical outcome, such as gait analysis (n 5 2) or smart pyramid-reported socket reaction moments (n 5 2).…”

“…Additional alignment parameters used include alignment jig (n 5 4) 57,61,65,74 and radiographic comparison (n 5 1). 56…”