Lower extremity joint kinematics of stair ascent in transfemoral amputees

Abstract

Background: Stair ascent is a very demanding task for transfemoral amputees (TFAs). The purpose of this study was to investigate the lower extremity joint kinematics of TFAs who can climb stairs using a step-over-step gait pattern without an active artificial prosthetic knee joint or handrail use. Case Description and Methods: Case series. Participants were two traumatic TFAs and 10 control participants. Both TFAs used a single-axis prosthetic knee joint in daily living. Sagittal plane joint kinematics were recorded at 60 Hz using an eight-camera motion analysis system and digital video camera. Findings and Outcomes: From the instant of touchdown, the prosthetic knee joint was rapidly extended and remained fully extended until toe-off. In the latter half of the stance phase, the knee and ankle joints of the sound limb simultaneously showed rapid joint flexion during continuous extension. Further, the ankle joint of the sound limb showed greater plantarflexion at the end of the stance phase. Conclusion: These results suggest that the TFA in the present study would (1) extend the prosthetic knee joint to prevent the knee flexion generated by the bodyweight (plus ground reaction force and/or joint moment), and (2) lift the whole body in an upward direction using strong counter-movements and greater joint extension during the stance phase. Clinical relevanceThe data describing the lower extremity joint kinematics of TFAs who can climb stairs in a step-over-step manner provides us with a basis for better understanding of adaptive prosthetic control and would be expected to aid in the development of more effective gait rehabilitation programme.

Stair ascent with an innovative microprocessor-controlled exoprosthetic knee joint

“…Climbing stairs step over step is diffi cult and is often not feasible with conventional prosthetic knee joints. It requires maximum strength, coordination, compensation, and motor performance to achieve and is reported by only a few amputees [1,8] . Previously, only one available knee component offered a stair-climbing function.…”

Foot clearance strategy for step-over-step stair climbing in transfemoral amputees

“…Byrne and Prentice 9 reported that a total knee arthroplasty patient was able to maintain toe clearance when overcoming obstacles by increasing hip flexor work during the elevation phase of swing. Furthermore, in our previous study, 5 TFAs who could climb stairs using the SOS strategy showed a greater hip flexion velocity in the prosthetic limb during the early swing phase compared to ABS, suggesting that the TFAs would intentionally flex their hip joints rapidly to replicate the knee joint in conjunction with the hip flexion. Hence, as corroborated by previous research, the present study showed that the combination of extension-flexion by the hip joint in the prosthetic leg during the early swing phase Prosthetics and Orthotics International 38 (4) could be an effective compensatory strategy to achieve foot clearance during SOS stair climbing in TFAs.…”

Novel knee joint mechanism of transfemoral prosthesis for stair ascent

“…This difficulty in ascending stairs is mainly due to the generation of a insufficient extension moment around the knee joint of the prosthesis to lift the body to the next step on the staircase and prevent any unexpected flexion of the knee joint in the stance phase. Hobara et al first demonstrated that a transfemoral prosthesis without an actuator and with very low friction allowed amputees to ascend stairs by developing a special gait through rehabilitation training [8]. Although this was an important finding, it involved users being trained to use the hip extensor and flexor for compensatory motion, which could lead to fatigue.…”