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To reduce ankle clonus in patients with spastic paresis either phenol nerve block of the tibialis posterior nerve or botulinum toxin type A (BTA) injection in triceps surae muscles can be used. This study aims to compare the efficacy over time of phenol nerve block and BTA injection in the inhibition of ankle clonus.Twenty-two patients with spastic paresis presenting with ankle clonus were randomly treated with phenol nerve block of the tibialis posterior nerve or BTA injection in triceps surae muscles. Ankle passive dorsiflexion, clonus, M and H responses and H/M ratio were measured in all patients prior to treatment and 15 days afterwards, as well as one, three and six months later in 12 patients. Patient satisfaction was also recorded.Both patient groups showed significant clonus reduction over time with the effect of phenol being greater than that of BTA. In one month, the degree of passive dorsiflexion significantly increased in both groups without any significant difference between them. H/M ratio reduced after phenol treatment and remained almost constant during the following six months, whereas it remained at baseline level after BTA treatment.While both treatments led to reduction in ankle clonus, phenol showed greater clinical efficacy. The difference in the neurophysiological results suggests that the two drugs have different action mechanisms with a more prevalent reduction of alpha motoneuron excitability in phenol-treated patients.

In vitro experimental tests are of great importance in human joint biomechanics. These tests allow the study of the kinetostatic and dynamic behaviour of human joints: a limb specimen is connected to a rig, controlled loads are applied, and the joint displacements are measured. Fixation of the bone to the rig is a typical problem that raises in these applications. A new fixation device is presented in this paper that features several interesting and innovative characteristics: it consists of a passive parallel mechanism that allows adjustment of the pose of the bone with respect to the rig with six degrees of freedom; if needed, the bone can be removed from the rig and repositioned exactly at the same pose during the experimental tests; all six degrees of freedom of the fixation device can be locked by acting only on two screws, thus simplifying the fixation operation; the parallel structure of the mechanism guarantees a high fixation stiffness. The complete design is presented and discussed, together with the results from the workspace and stiffness analyses of the mechanism, that are particularly important for the considered applications.

Background The aim of this study is to assess the clinical value of a recently introduced original protocol for full three dimensional analysis of ankle rotations in patients with equinovarus foot. Methods A preliminary study merging the Total3Dgait protocol and the conventional Vicon® Plug-in-Gait marker-sets on five patients with foot deformity was performed to compare the output exactly over the same gait cycles. In the second study, 15 patients with equinus varus foot were assessed retrospectively by means of the Total3Dgait protocol before and after surgery. Data on ankle kinematics were compared to those of a control group. The Functional Ambulation Categories scale and other goals such as orthosis/aids removal, decrease in foot pain, healing of calluses and sores were considered as measures of clinical outcome. Findings The Total3Dgait protocol provides additional joint motion, in the coronal and transverse planes. Kinematics in the three anatomical planes improved significantly although no changes in time-distance parameters were evident. Improvement in clinical outcome measures was also achieved. Interpretation The new protocol provides valuable additional data in measuring full three dimensional kinematics of the foot during gait. Whereas the speed of walking was unchanged after surgery for most of patients, the kinematic changes in the three anatomical planes, as measured by the new protocol, were the only measures able to demonstrate motion changes induced by surgery at the foot and to explain subject-specific gains as improvement in stability during walking, relief of pain, calluses and sores, and removal or modification of foot orthosis and aids.

The reliability of kinematic measurements has a top priority in gait analysis. The aim of the present work was to assess the inter-trial, inter-session and inter-examiner variability of an anatomical-based protocol by an established method. The gait of two young adult volunteers was analyzed by four examiners with different degrees of experience in three sessions 1 week apart. The data of five trials of level walking were collected and the rotations in the three anatomical planes of the pelvis, hip, knee and ankle were calculated. Themean value over the gait cycle of the standard deviation of these rotations wascalculated for each of the 24 groups of five trials (inter-trial), the eight groups of five trials multiplied by three sessions (intersession), and the two groups of five trials multiplied by three sessions multiplied by four examiners (interexaminer). For each rotation, the inter-examiner variability was larger than the inter-session, and the latter larger than the inter-trial. The present ratio between inter-examiner and inter-trial variability wasfound to be smaller than that of the conventional protocol for each of the gait variables. 2010 Elsevier B.V. All rights reserved.

Most widespread clinical gait analysis protocols for lower limb kinematics provide information about the ankle motion only in the sagittal plane. Behavior of the foot in the coronal plane during gait is usually determined just through the measure of the foot angle of progression. In the clinical practice most of the patients, particularly with upper motor disease, present a complex deformity of the foot in the three anatomical planes, most frequently in equinus, varus, supinated foot. Adequate kinematic analysis requires full consideration of the 3D ankle-foot complex position and motion on the basis of appropriate biomechanical conventions. The aim of the present work is to test the efficacy of current kinematic protocols for gait analysis in the measurement of 3D motion in stroke patients with foot deformities before and after surgery.

Racconto filosofico sviluppato all'interno del laboratorio di design dello spazio della Facoltà del Design, Politecnico di Milano.