PhD position at LIRMM, Université Montpellier, France

PhD position available at LIRMM, Université Montpellier, France
Title : Prolonged Functional Balanced Standing in paraplegic patient

The standing posture in paraplegic patient can be obtained by knee joint locking. Different approaches are possible: verticalizing wheelchairs, orthosis, Vanini boots, functional electrical stimulation (FES).

Orthoses and Vanini boots allow to lock the knee and the ankles and in some cases to free one or two hand. A visual feedback is necessary for the patient to ensure his vertical alignment.

Electrical stimulation is interesting as it would allow to have in a longer term a completely implanted version of the system and therefore largely more acceptable by the patient. The electrical stimulation of biceps femori allows to lock knee joint but involves high current intensity levels which fatigue quickly the muscles and lead to early joint unlocking. conduisent trop rapidement à un déverrouillage de l’articulation. We propose here to explore orthoses, Vanini boots and FES solutions and combine them if necessary to achieve long term functional balanced standing (allowing to free one hand to grasp an object).

More precisely, we will study :

1) Knee locking under surface FES
Several strategies will be considered : 1) moving from continuous stimulation to intermittent one , 2) alterning stimulation on the two sides, 3) optimizing stimulation patterns (frequency, amplitude, …), 4) involving frontal plane movements (lateral oscillations) and stimulating other muscles. (lateral oscillations controlled by verticality of the trunk), 5) bifocal stimulation of thigh muscles, 6) matrix stimulation to modify the localization of stimulation point.

2) Balance control
We will propose strategies to ensure balance by combining different solutions (orthoses, Vanini boots, FES)
Keywords:
- musculo-skeletal modelling
- involvement in clinical experiments
- analysis of experimental data

This PhD thesis will be co-supervised by PhD Christine AZEVEDO, PhD David GUIRAUD, MD PhD Charles Fattal (PROPARA) and Pr. P. Fraisse.

Contact: fraisse@lirmm. fr, azevedo@lirmm. fr