Using Stubby Prosthesis after Bilateral Transfemoral Amputation: A Biomechanical Case Study

Abstract

Background: After bilateral transfemoral amputation, people may experience limitations in everyday life due to limited mobility and prosthesis problems. Materials and method: The case study covered a 54-year-old man after bilateral traumatic amputation of his lower limbs. Transfemoral amputations were performed using the Caldwell method; disproportion in the length of stumps was 5 mm. The motion task was recorded using the SMART-E optoelectronic system (BTS Bioengineering, Milan, Italy) according to the standard Davis protocol (the Newington model). Biomechanical evaluation included the measurement of angle-time relationships, characterizing the range of motion (ROM) in lower limb joints and Ground Reaction Force (GRF). The analyzed tasks are walking with self selected speed, fast gait and walking in stubby prostheses. Results: Step width was the most similar to the gait of healthy persons walking with stubby prostheses (0.17 ± 0.01 m for healthy people, 29% higher for stubbies, 35% for prosthetic gait with self-selected gait speed and 41% for fast gait speed). Step width was the smallest when walking with stubbies. Conclusions: The reduction of body height allows to reduce the risk of fall. Higher metabolic cost of gait in people after amputation result from a greater need to maintain balance and posture, and to perform walking movement.

Hip joint and muscle loading for persons with bilateral transfemoral/through-knee amputations: biomechanical differences between full-length articulated and foreshortened non-articulated prostheses

“…Interestingly, participants showed higher cadence with stubbies than full-length articulated prostheses and AB. This may indicate an attempt to maintain similar walking speeds to those achieved with prosthetic knees by increasing cadence [ 19 ], which was not sufficient given the lower stride lengths with stubbies. Unlike stubbies, BTF with full-length articulated prostheses needed to adopt larger stride lengths to be able to swing the full-length prosthesis back from a larger hip extension position, which ultimately created higher hip flexion moments, burdening the hip flexor muscles, in accordance with previous literature that demonstrated high hip flexors activations during gait compared to persons without limb loss [ 3 ].…”

“…However, these studies did not analyse the biomechanical effect of different prosthetic designs on the BTF musculoskeletal function and loading, as all participants were fitted with microprocessor knees and dynamic response feet. The biomechanics with stubby prostheses has been previously presented in case studies, which showed slower walking speeds [ 18 , 19 ] and higher oxygen cost when used for long distances [ 20 ] compared to conventional full-length articulated prostheses. Previous studies focused on spatiotemporal, metabolic, kinematics and dynamic measures, excluding other relevant physiological aspects such as muscle and joint contact forces, that are related to pathology.…”