A prosthetic or orthotic device using at least one of measurements of residual limb length or circumference to define a prosthetic socket assembly configuration, comprising modular socket components fitted to the individual user's residual limb having a mounting point for an attachment, at least one compliant member attached to at least one stabilizing unit, and at least one second compliant member attached to at least one stabilizing unit wherein the first compliant member and the second compliant member work in cooperation with the stabilizing unit(s) to control bone position and support the limb within the interface.