Knee muscle activity during ambulation of trans-tibial amputees.

Gait analysis of trans-tibial amputees brings to light asymmetries of different gait parameters between the amputated and sound legs. The present study investigated the activity of the vastus medialis and biceps femoris muscles during ambulation of trans-tibial amputees. Peak activities of the vastus medialis were reached similarly in both legs (6.06+/-4.9% and 8.84+/-3.6% of gait cycle, in the sound and amputated leg, respectively). Biceps femoris peak activities were reached at 92.43+/-6.6% of gait cycle in the sound leg, and significantly later (at 9.81+/-4.8% of gait cycle) in the amputated leg (p < 0.05). Integrated EMG activity ratios, between swing and stance periods, were similar for the vastus medialis (0.33 in the sound and 0.35 in the amputated leg). However, these ratios differed significantly for the biceps femoris since the amputated leg presented a substantial (p < 0.05) smaller ratio (0.22) compared with the sound leg (0.83). The use of prosthesis in trans-tibial amputees requires further activity of the biceps femoris during stance period to improve support of the amputated leg knee joint.

Multichannel electrical stimulation of gait in motor disabled patients.

Effects of surface multichannel electrical stimulation of the leg muscles during gait were evaluated by a clinical kinesiological analysis of gait and measurements of average step length, gait velocity, ground reaction forces, and joint angles. Direct effects in 11 stimulated motor disabled patients showed 56% improvement at the kinesiological gait analysis during the stimulation. Long term effects of the multichannel therapy were compared in a threeyear control study with a group of ten nonstimulated patients. At the kinesiological analysis, the stimulated group improved 1.75 times better after 2.5 months of the treatment. The other measurements revealed higher and faster improvement at the stimulated group with a partial decrease of the therapeutic effects after a longer period without treatment. Orthotic multichannel stimulation was indicated after the multichannel therapy in the clinical environment, where the stimulation of proximal leg muscles was favored.

Influence of speed on gait parameters and on symmetry in trans-tibial amputees.

Normal gait is characterised by a high level of inter-leg symmetry of gait parameters. Therefore, efforts in rehabilitation of amputees are directed at the construction of a prosthesis which provides normal leg function and allows a more symmetrical gait. Analysis of the gait of trans-tibial amputees was performed when they were ambulating at their own freely selected speed and at a faster speed. The effect of speed on selected gait parameters in each leg was evaluated and the influence on symmetry established by comparing the inter-leg changes for each of the selected parameters. The faster gait trail affected significantly all temporal and distance parameters in both legs but not the level of symmetry between legs. At the faster speed, the hip angles at heel-strike and during swing and the knee angle during load response, in the normal leg, and the knee angle during swing in the amputated leg, all increased significantly. Speed of gait significantly affected symmetry between knee angles as reflected by the increased differences measured during load response (from 2.62 +/- 5.2 to 7.06 +/- 4.2 degrees) and during toe-off (from 1.80 +/- 7.4 to 9.50 +/- 9.1 degrees). Timing and sequence of selected gait events, as related to stride time, were not significantly affected by speed of gait. These results might contribute to a better understanding of gait characteristics in trans-tibial amputees and provide design guidance for prosthetic components.

Altered likelihood of brain activation in attention and working memory networks in patients with multiple sclerosis: an ALE meta-analysis.

Multiple sclerosis (MS) is a chronic neurological disease, frequently affecting attention and working memory functions. Functional imaging studies investigating those functions in MS patients are hard to compare, as they include heterogeneous patient groups and use different paradigms for cognitive testing. The aim of this study was to investigate alterations in neuronal activation between MS patients and healthy controls performing attention and working memory tasks. Two meta-analyses of previously published fMRI studies investigating attention and working memory were conducted for MS patients and healthy controls, respectively. Resulting maps were contrasted to compare brain activation in patients and healthy controls. Significantly increased brain activation in the inferior parietal lobule and the dorsolateral prefrontal cortex was detected for healthy controls. In contrast, higher neuronal activation in MS patients was obtained in the left ventrolateral prefrontal cortex and the right premotor area. With this meta-analytic approach previous results of investigations examining cognitive function using fMRI are summarized and compared. Therefore a more general view on cognitive dysfunction in this heterogeneous disease is enabled.

The use of ground reaction measuring shoes in gait evaluation.

Ground reaction force is one of the most relevant parameters in the assessment of human gait. It is, however, difficult to measure without encumbering natural locomotion. A description of a system for measuring the vertical component of the ground reaction force and its distribution under the foot is given. The calibration procedure for the measuring shoes is described. The results of measurements are compared with those obtained from a force plate. Illustrative examples of the changes in pathological gait patterns of a hemiplegic patient during therapy by functional electrical stimulation are also given.

A quantitative method of evaluation of gait under the influence of electrical stimulation in hemiparetic patients.

To improve the procedure of selecting stimulation parameters for the best functional movement, quantitative gait evaluation was investigated. Based on the information obtained by force measuring shoes and a goniometric system, the method consists of computing average values and standard deviations of ground reaction and its point of action, goniometric functions, as well as the ankle joint torque in the sagittal and frontal plane, and their graphic representation. Deviation of the measured variables with respect to the normal gait pattern is the measure of the gait quality. Stimulation parameters were adjusted so that the patient's gait pattern approached normal.

[The use of cartilage and tissue adhesives for the treatment of surgical-stomatological diseases in old age]. / Die Anwendung von Knorpelgewebe und Gewebekleber zur Behandlung chirurgisch-stomatologischer Erkrankungen im Senium

The authors used lyophilized cartilage in plate, bar, chip or powder form in elderly patients. The transplant was also utilized in managing defects resulting from the removal of jaw cysts, bone tumours, etc. Furthermore, the authors treated bone defects of the anterior wall of the maxillary sinus and of the hard palate as well as oro-antral perforations, infected wounds of the soft tissues and inflammatory bone processes. The patients in question had been treated in the surgical service during the years 1959--1975. The authors observed in elderly patients pathological alterations of the capillaries, haemorrhagic tendency and impairment of the blood-clotting mechanism. Furthermore, they found that the granulation tissue was of poor quality. In these cases they used cartilaginous tissue in powder form which promotes the formation of granulation tissue well supplied with blood. In the patients mentioned, the authors also utilized surgical adhesive, namely after tooth extractions and in managing their complications.

[The treatment of mandibular fractures, complicated by inflammations in the fracture area, by means of xenogenic cartilage]. / Uber die Behandlung von Unterkieferbrüchen mit entzündlichen Komplikationen im Frakturbereich mittels xenogenem Knorpelgewebe.

The authors used a personal technique for the management of infected jaw fractures. If the fracture cleft was not wider than 1 cm, they performed a surgical revision (having made an incision through the mucoperiosteum of the oral vestibule) and replaced the excochleated gra-ulation tissue (including sequestrums) by lyophilized cartilage. The bone fragments were immoblized by bone sutures previously applied and also by additional plastic splints. The substitution of the cartilage by bone begun 6-8 weeks after the surgical intervention (as evidenced by radiographs); the process had terminated in about 6-10 months, the implanted cartilage being completely replaced by newly formed bone. The observation involved 16 cases. The method is also recommended for treatment on an out-patient basis.

Gait restoration in paraplegic patients: a feasibility demonstration using multichannel surface electrode FES.

Recent advances in science have aided research toward the restoration of biped gait in paraplegic patients by means of functional electrical stimulation (FES). In this paper it is shown how FES-restrengthened muscles of paraplegic patients have been used for simple FES-assisted standing. Those experiments subsequently led to biped gait-initializing experiments and to simple forms of biped gait synthesis. The purpose of this paper is to show the feasibility of using FES for standing and for restoring biped gait in many paraplegic patients--to present the past achievements, focus on problems, and highlight directions for future research. The results of gait obtained in three complete spinal cord injured patients (out of a series of 17) are shown, using four to six channels of FES. It is also shown how preserved reflex mechanisms of the transected spinal cord can be incorporated and employed for obtaining improved function while at the same time simplifying the FES hardware. Of the three patients reported on in detail here, two patients have managed to walk in parallel bars while the third patient has mastered independent unassisted walking over shorter distances with the aid of a roller walker. The biomechanical and control problems of this last patient's gait are presented in detail.

Double-limb support and step-length asymmetry in below-knee amputees.

The sequence of gait events and symmetry of kinematic parameters between both lower limbs are compromised in below-knee amputees. In the present study the periods of double-limb support and the step length in below-knee amputees were investigated. The symmetry of the two periods of double-limb support occurring in each stride was obviously abnormal (ratio: 0.74) among temporal and distance parameters. The time of double-limb support (0.211 +/- 0.05 seconds) measured from heel-strike of the amputated leg until toe-off of the normal leg was significantly longer (p = 0.011) when compared with the contralateral leg (0.173 +/- 0.04 seconds). The step length of the normal leg (0.709 +/- 0.07 m) was significantly (p = 0.045) shorter than that of the amputated leg (0.752 +/- 0.08 m). Most of these differences between measured kinematic parameters can be explained by the limited ability of the prosthesis ankle-foot component to reproduce the normal functions of both foot and ankle.

Ankle muscle activity before and after botulinum toxin therapy for lower limb extensor spasticity in chronic hemiparetic patients.

BACKGROUND AND PURPOSE: Recent studies have been made of the novel treatment of lower limb spasticity after stroke with botulinum toxin A, and the results were based mostly on the clinical assessment made before and after treatment. This study investigated the effects of toxin on ankle muscle activity during gait in patients with severe extensor spasticity. The questions posed were whether the toxin particularly diminishes the so-called premature muscle activity as a major cause of equinovarus deformity and whether different types of altered motor control allow a prediction of the outcome of the treatment. METHODS: In 12 chronic hemiparetic outpatients with pronounced lower limb spasticity, we injected 400 U botulinum toxin A into the soleus and tibialis posterior muscles and both heads of the gastrocnemius muscles. Ankle spasticity and complex gait analysis including kinematic electromyography (EMG) of the soleus and tibialis muscles were assessed before treatment and 4 weeks after the injection. RESULTS: Nine patients profited with a reduction of spasticity, improved gait ability, and a more normal temporal pattern of muscle activity with a prominent reduction of the premature activity of the plantar flexors. Eight patients exhibited a qualitative pattern (type I) corresponding to an increased stretch-reflex excitability. Three patients did not profit; their muscle tone, gait ability, and muscle activation remained stable or even deteriorated. CONCLUSIONS: This study further supports the beneficial effects of botulinum toxin in the treatment of lower limb extensor spasticity. A correlation was observed between the clinical reduction of muscle tone, functional gait parameters, and a more normal EMG pattern with a predominant reduction of the premature activity of the plantar flexors. The qualitative type of EMG pattern corresponding to an increased stretch-reflex excitability (type I) was a positive predictor for the outcome.

Therapeutic effects of multisite electric stimulation of gait in motor-disabled patients.

Therapeutic effects in ten hemiplegic patients and one paraparetic patient treated by multisite electric stimulation of gait were compared with effects in ten hemiplegic patients treated by standard rehabilitation methods after 2.6 months of extensive therapy. Average step length and gait velocity, ground reaction forces and their distribution under both feet, and crutch loading were measured; goniograms of joint angles, kinesiologic gait analysis, and EMG recordings from the main muscles used in ambulation and in standing, were made while patients in both groups walked without stimulation. Quantitative measurements before, during, at the end, and 8.4 months posttherapy were taken based on at least 40 strides per patient. The results for the stimulated group in midtherapy indicated faster recovery rates (3.15 times in step length and 2.25 times in gait velocity) than in the control group, and at the end of therapy the stimulated group had higher improvement levels (2.14 times in step length, 1.42 times in gait velocity, and 1.63 times in kinesiologic gait analysis). The differences between the two groups faded after 8.4 months without treatment, and some kinesiologic deficits reappeared, mostly those in the more distal muscle groups. These findings indicate a need for a simpler orthotic electric stimulation after multisite therapy in several cases. Immediate effects of the six-site stimulation were also considered for orthotic possibilities after the therapy.