A second study involved 32 subjects, 16 healthy controls and 16 transtibial amputees using the Proprio Foot (Alimusaj, 2009). The subjects underwent three-dimensional (3D) gait analysis on stairs. Kinematics and kinetics of the lower limbs were compared during stair ascent and descent with the prosthetic foot set to a neutral ankle angle and then with an adapted dorsi-flexion ankle angle of 4 degrees. Comparisons were also made between experimental group subjects and control subjects. The study concluded that for both stair ascent and descent, the prosthesis resulted in an improvement in kinematic and kinetic measures of the knee with an increase of knee flexion and increase of the knee stability during stance.
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Like many operations, the outcomes of surgery cannot be absolutely guaranteed but for those who are deemed to be suitable, a benefit can be expected in over 85% of patients. Results data at the Oxford Lymphoedema Practice is grouped by the starting volume discrepancy (as measured by digital perometry) into low, medium and high volume groups. Low volume groups will have a lesser benefit in terms of absolute volume reduction (because their volume discrepancy is low to start with) but surgery may bring benefits with reduction in garment requirement and in reduction of lymphoedema deterioration in the longer term. Medium and larger volume discrepancy patients typically benefit from a reduction in limb volume discrepancy and in how tense or tight the limb feels. Reduction of limb volume discrepancy by 50% would be not uncommon and depending on the approach of the patient, a reduction in requirement to wear compressive garments may result from this. There is good scientific data demonstrating a reduction in incidence of post-operative cellulitis after LVA surgery. Whilst strong evidence exists for this surgery in general, for any given individual it is impossible to predict their degree of response as this will rely largely on the actual nature of their lymphatic channels at the time of surgery. (For this reason it is important to counsel patients carefully about their potential chance of benefitting from undergoing surgery. Expectation management by the treating surgeon(s) is an important part of assessment and it is important that such discussion is undertaken in detail.)
23: Physical Therapy Management of Adult Lower-Limb …
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For individuals who have lost a limb below the knee, there is a need for a device to replace the function of the ankle and foot. Stair ambulation is limited in the transtibial amputee due to the neutral and fixed ankle position which exists in traditional prosthetic ankles. Under study are newer prosthetic ankles which adjust the foot-ankle angle during the swing phase using sensor and microprocessor technologies to identify sloping gradients and the ascent or descent of stairs after the first step. Users can place the foot fully on a step when climbing or descending stairs and it will automatically adapt the ankle position to enable the next step. On ramp ascent and descent, adaptation begins on the second step and the device makes small adjustments until it reaches the degree of slope of the ramp. The Proprio Foot is one such "quasi-passive" device. The device is passive since no power is generated through the ankle in stance. The device is also said to be designed to dorsiflex, or bring the toes closer to the shin, during the swing phase to improve ground clearance, improve gait symmetry and reduce the likelihood of falls. Other claims include the device's ability to assist in standing from a seated position and plantar (bottom of the foot) flexion when kneeling, sitting and lying down. Early pilot studies suggest that both during stair ascent and descent, the Proprio Foot improves knee flexion kinematics. The weight of the Proprio Foot device is more than twice the weight of a conventional ankle-foot prosthetic such as the LP Vari-Flex (995g versus 405g). Concern has been raised that because of its weight, the Proprio Foot might not benefit amputees with limited endurance and knee musculature.