Gait Inefficiency in Trans Tibial Amputation

A significant amount of investigation has been undertaken in trans tibial amputees in order that a more efficient energy store can be constructed for the foot-ankle. The beneficial effect of the knee with respect to weight acceptance (loading response) remains and the main deficiency is the inability to eccentrically power the ankle at initial contact and concentrically power it at terminal stance-pre swing. Carbon fiber foot prostheses can emulate the energy storeage characteristics of the normal leg sufficiently to allow running (Strike). Increasingly sophisticated designs of foot construct return higher proportions of loading response energy (Flex 84%, Seattle 52% and Solid ankle cushion heel 31% Czerniecki)

Gailey (1997) has shown that the mass of a below knee limb is not critical to gait efficiency. A comparison of those with short stumps and those with long stumps revealedd that a short stump is associated with an inefficient gait. Attempts at matching the inertial properties of the normal limb lead to increased energy expenditure (Mattes).

References

Czerniecki JM, Gitter A, Munro C. Joint moment and muscle power output characteristics of below knee amputees during running: the influence of energy storing prosthetic feet. J Biomech 1991;24(1):63-75.

Gailey RS, Nash MS, Atchley TA, et al. The effects of prosthesis mass on metabolic cost of ambulation in non-vascular trans-tibial amputees. Prosthet Orthot Int 1997;21(1):9-16.

Mattes SJ, Martin PE, Royer TD. Walking symmetry and energy cost in persons with unilateral transtibial amputations: matching prosthetic and intact limb inertial properties. Arch Phys Med Rehabil 81(5):561-8.

Strike S, Hillery M. The design and testing of a composite lower limb prosthesis. Proc Inst Mech Eng [h] 214(6):603-14.

16% less efficient:

Gailey RS, Wenger MA, Raya M, et al. Energy expenditure of trans-tibia amputees during ambulation at self-selected pace. Prosthet Orthot Int 1994;18(2):84-91.