This consists of a short-latency response (SLR) corresponding
to the mono- and oligosynaptic reflex and a medium-latency response (MLR) relayed by group-II spindle afferent fibers and likely made of a segmental burst and a transcortical loop.
Soleus (Sol) SLR and MLR were evoked by toe-up and tibialis anterior (TA) MLR by toe-down platform rotation in 15 standing subjects and recorded by surface electromyogram (EMG). For each stimulus type, up to 20 perturbations were elicited during i) quiet stance (Control) and while ii) performing JM, iii) leaning forward (FW), iv) holding onto a stable frame (Holding). For each subject, stimulus type and condition, rectified EMG traces were averaged. Based on the comparison of the population PSI-7977 datasheet grand averages, selective effects of JM on the responses were identified. Appropriate time windows were set for measuring the area of SLR and of the early and late burst AZD1080 of MLR (MLR1 and MLR2).
Significant changes in response size, but not latency, were induced by all conditioning procedures. During toe-up, JM slightly increased Sol SLR; FW increased both Sol background activity and SLR; MLR1 was not affected by JIM, but increased by FW; MLR2 was
strongly diminished by JM and increased by FW. During toe-down, JM did not affect TA MLR1, but strongly diminished MLR2. Under Holding condition, Sol SLR to toe-up was unaffected, but both MLR1 and MLR2 to toe-up and toe-down were diminished, in both Sol and TA.
JM selectively decreases the response component (MLR2) starting about 100 ms from onset of the stretch, in both extensor and flexor muscles. Latency and quality of the JIM effect on MLR2 indicate that JM operates by gating a long-loop, possibly transcortical pathway. This new information suggests that lesions of cortical areas or descending pathways can exert enhancing effects on muscle tone by removing an inhibitory action on the late component
of the stretch reflex. (C) 2008 IBRO. CHIR99021 Published by Elsevier Ltd. All rights reserved.”
“Background: For good rehabilitation candidates, the biomechanical advantages of the end weight-bearing through-knee amputation (TKAmp) compared with the above knee amputation (ARA) are well established. However, the TKAmp has been abandoned by vascular surgeons because of poor wound healing rates related to long tissue flaps and challenges to prosthetic fitting related to the femoral condyles. Since 1998, we have performed the modified “”Mazet”" technique TKAmp procedure that creates shorter flaps to close the wound and greatly facilitates prosthesis fitting. The purpose of this study is to review our results with TKAmp in patients with peripheral vascular disease who were not candidates for below-knee amputation.
Methods: The records of all patients who underwent through-knee amputation between 1998 and 2006 were retrospectively reviewed. Mean follow-up was 33 months (range, 38 days to 99 months).