The reversible adjustable coupling: A lightweight and low-cost alignment component for the lower limb prosthesis:

BackgroundThe alignment of the lower limb prosthesis is an integral part of the prosthetic fitting. A properly aligned prosthesis contributes to optimal gait and overall function of the patient. The current offering of alignment componentry is expensive for low-income countries. The purpose of this study was to develop a lightweight and low-cost alignment coupler for the lower limb prosthesis.MethodsAn alignment coupler called the reversible adjustable coupling was designed and manufactured. Measurements of total anterior/posterior and medial/lateral and rotation in prostheses were recorded and mechanical testing performed. Swiftness and difficulty of use was also recorded.ResultsThe reversible adjustable coupling permitted acceptable ranges of anterior/posterior and medial/lateral translation and 30° of internal and external rotation of prosthetic componentry. Repetitive loading of the coupling at a speed of 1 Hz under 1.28 kN load for 2000 cycles was successful, as were static and strength tests.Discuss...