![[ Visit Client Website ]](images/banner.gif)
Wednesday, September 24, 2008: 10:00 AM
Auditorium (Palazzo dei Congressi di Stresa)
Pseudoelastic alloys have never been utilised in rehabilitation medicine yet. A compliant dynamic brace (EDGES) promoting spastic elbow relaxation was designed for clinical use and helped investigate the potentialities of pseudolastic NiTi in orthotics. Due to the great deformability of these materials, EDGES yields under involuntary jerks (ensuring the patient feels no pain), but, as soon as jerks fade, it starts anew exerting a constant mild force on the arm. Such a continual corrective push could be effective in improving limb posture by eliciting the relaxation of contracted tissues, without provoking spastic reflexes.
Thermal (DSC), and mechanical (traction and bending tests) characterisation was carried out to select the most suitable heat treatment for a commercial Ni50.7-Ti49.3 grade. 400° 1h+WQ was chosen, guaranteeing plateau values of σm=500MPa and σr=250MPa. A prototype of EDGES was assembled with two thermoplastic shells connected by polycentric hinges. Four 2mm-diameter NiTi bars were encastred in the upper-arm shell while they could slide along tubular fixtures on the forearm.
Three post-stroke subjects (62.3±1.5y/o, mild elbow flexors spasticity) wore EDGES for 2 weeks, at least 10h a day. No additional treatment was applied to the examined arm during this period or the following week. A great improvement (20°±5°) of the resting position was observed in all patients as early as 3h after starting the treatment. During walking, EDGES did not constrain limb movements and was thus very well accepted by the patients. A slight decrease in elbow flexors spasticity was also observed in all subjects, but this effect disappeared 1 week after discontinuation, as did posture improvements.
EDGES appears to be a good alternative to traditional orthoses in terms of acceptability and effectiveness in improving posture, and it could be very useful whenever short-term splinting is planned. Other orthoses could be significantly enhanced by utilizing pseudoelastic NiTi.
Thermal (DSC), and mechanical (traction and bending tests) characterisation was carried out to select the most suitable heat treatment for a commercial Ni50.7-Ti49.3 grade. 400° 1h+WQ was chosen, guaranteeing plateau values of σm=500MPa and σr=250MPa. A prototype of EDGES was assembled with two thermoplastic shells connected by polycentric hinges. Four 2mm-diameter NiTi bars were encastred in the upper-arm shell while they could slide along tubular fixtures on the forearm.
Three post-stroke subjects (62.3±1.5y/o, mild elbow flexors spasticity) wore EDGES for 2 weeks, at least 10h a day. No additional treatment was applied to the examined arm during this period or the following week. A great improvement (20°±5°) of the resting position was observed in all patients as early as 3h after starting the treatment. During walking, EDGES did not constrain limb movements and was thus very well accepted by the patients. A slight decrease in elbow flexors spasticity was also observed in all subjects, but this effect disappeared 1 week after discontinuation, as did posture improvements.
EDGES appears to be a good alternative to traditional orthoses in terms of acceptability and effectiveness in improving posture, and it could be very useful whenever short-term splinting is planned. Other orthoses could be significantly enhanced by utilizing pseudoelastic NiTi.