The influence of a user-adaptive prosthetic knee across varying walking speeds: A randomized cross-over trial.

Previously conducted trials comparing the gait pattern of individuals with a transfemoral amputation using a user-adaptive and a non-microprocessor-controlled prosthetic knee (NMPK) found mixed and conflicting results. Few trials, however, have compared user-adaptive to non-adaptive prosthetic knees across different walking speeds. Because of the ability of variable damping, the effect of user-adaptive knees might be more pronounced at lower or higher walking speeds. Our aim was to compare the Rheo Knee II (a microprocessor-controlled prosthetic knee) with NMPKs across varying walking speeds. In addition, we studied compensatory mechanisms associated with non-optimal prosthetic knee kinematics, such as intact ankle vaulting and vertical acceleration of the pelvis. Nine persons with a transfemoral amputation or knee disarticulation were included and measured with their own NMPK and with the Rheo Knee II. Measurements were performed at three walking speeds: preferred walking speed, 70% preferred walking speed and 115% preferred walking speed. No differences on peak prosthetic knee flexion during swing were found between prosthetic knee conditions. In addition, prosthetic knee flexion increased significantly with walking speed for both prosthetic knee conditions. At 70% preferred walking speed we found that vaulting of the intact ankle was significantly decreased while walking with the Rheo Knee II compared to the NMPK condition (P=0.028). We did not find differences in peak vertical acceleration of the pelvis during initial and mid-swing of the prosthetic leg. In conclusion, comparison of walking with the Rheo Knee II to walking with a NMPK across different walking speeds showed limited differences in gait parameters.

Early treatment of trans-tibial amputees: retrospective analysis of early fitting and elastic bandaging.

This study investigates the effects of early fitting in trans-tibial amputees. The assumption is that compared to elastic bandaging, the use of a rigid dressing in early fitting will result in quicker wound healing and earlier ambulation. A retrospective file search was carried out in three different hospitals, analysing the time to first prosthesis, the incidence of local and general complications and the functional outcome after discharge from hospital. Each of the hospitals used a different method of postoperative care: elastic bandaging, immediate postoperative application of the plaster cast or delayed application of the plaster cast within one week post amputation. In comparison to the elastic bandaging method (N=52), the use of a rigid dressing in the early fitting method (immediate and delayed, N=97) resulted in a statistically significant shorter period from amputation to the delivery of a first regular prosthesis (110 days vs 50 days) and a decreased risk of knee flexion contracture. Although, differences in local complications were not observed, the risk of pressure sores in other places than the stump was increased in early fitting. Instead of further reducing the time to first prosthesis by immediate fitting, the use of delayed fitting resulted in a statistically significant shorter period from amputation to the delivery of a first regular prosthesis (56 vs 40 days). However, delayed fitting was associated with an increased risk for reamputation. In conclusion, this study indicates that early fitting by use of a rigid dressing after trans-tibial amputation is the treatment of choice. If it is possible to apply a plaster cast in the operating room, the authors would prefer the immediate fitting method.

Cervical muscle dysfunction in the chronic whiplash associated disorder grade II (WAD-II).

STUDY DESIGN: In a cross-sectional study, surface electromyography measurements of the upper trapezius muscles were obtained during different functional tasks in patients with a chronic whiplash associated disorder Grade II and healthy control subjects. OBJECTIVES: To investigate whether muscle dysfunction of the upper trapezius muscles, as assessed by surface electromyography, can be used to distinguish patients with whiplash associated disorder Grade II from healthy control subjects. SUMMARY OF BACKGROUND INFORMATION: In the whiplash associated disorder, there is need to improve the diagnostic tools. Whiplash associated disorder Grade II is characterized by the presence of "musculoskeletal signs." Surface electromyography to assess these musculoskeletal signs objectively may be a useful tool. METHODS: Normalized smoothed rectified electromyography levels of the upper trapezius muscles of patients with whiplash associated disorder Grade II (n = 18) and healthy control subjects (n = 19) were compared during three static postures, during a unilateral dynamic manual exercise, and during relaxation after the manual exercise. Coefficients of variation were computed to identify the measurement condition that discriminated best between the two groups. RESULTS: The most pronounced differences between patients with whiplash associated disorder Grade II and healthy control subjects were found particularly in situations in which the biomechanical load was low. Patients showed higher coactivation levels during physical exercise and a decreased ability to relax muscles after physical exercise. CONCLUSIONS: Patients with whiplash associated disorder Grade II can be distinguished from healthy control subjects according to the presence of cervical muscle dysfunction, as assessed by surface electromyography of the upper trapezius muscles. Particularly the decreased ability to relax the trapezius muscles seems to be a promising feature to identify patients with whiplash associated disorder Grade II. Assessment of the muscle (dys)function by surface electromyography offers a refinement of the whiplash associated disorder classification and provides an indication to a suitable therapeutic approach.