SCI Orthotics SCI Orthotics

Review Nomenclature Spine support orthoses Joint support orthoses Neck, ThoracoLumbarSacral Joint support orthoses Typically lower limb motor loss adaptations Motor augmentation orthoses Typically upper limb motor presence augmentation Protection orthoses

Orthotic Definition Device used to assist, resist, align or simulate function of a body part or system. Typically applies forces to affected extremity. Force has magnitude, direction and application point. Effectiveness depends on all 3. Movement = rotation, translation or combination of 2. Torque is strength of rotational force.

Orthotic Nomenclature 1971 – American Orthotic and Prosthetic Association promoted standardized nomenclature 1972 – new language put into use

Committee on Prosthetic-Orthotic Education of the National Academy of Sciences All exoskeletal devices called orthotics Described by joints they encompass Abbreviate each joint name to 1 letter Combination of symbols to indicate desired control of designated function

Orthotic Materials Thin metal, plastic, foam, epoxy, plaster. Short use = low durability need High frequency & load = high durability need

Spine Support Goal is stabilization in desired plane of motion Flex/ext, sidebending, rotation Absolute vs. relative restriction

Cervical Orthoses Halo SOMI, molded MINERVA cervical orthosis ASPEN, Miami, PHILLY MNDA for weak extensors (ALS) Headmaster collar Soft collar

Cervical Orthoses Philly: AP motion limited to 30% normal, 43% rotation, 67% side bend. SOMI: 13-27% sagittal motion, 34% rotation, 66% side bend HALO: believed most restrictive, least overall C-spine motion but individual “snaking” of vertebrae. Koch – 31% sagittal motion reduction in tetraplegia, suggested intimate fit body vest was best. 1978

ASPEN Collar

Miami collar

MNDA

ThoracoLumbarSacral Orthoses 3 point force application theory No true immobilization, just limitation of interspinous motion Limited sagittal control For effectiveness, must provide “inhibitory feedback signal” over bony prominences to reduce patient movement efforts.

LS Orthoses Commonly used for back pain syndromes Little consistent data to support idea that disk pressures reduced in lifting tasks. Nachemson A.

TLSO types Jewitt Knight-Taylor LS corsett Clamshell or turtleshell

Limb Support Orthoses Reciprocating gait orthosis HKAFO KAFO AFO

Motor Augmentation Orthoses Cervical deficits can use substitution or enhancement Upper limb’s job = terminal device (hand) placement in environment Feeding most important! Balanced forearm orthosis (BFO), tenodesis devices, hand & digit flexion or extension assist orthoses, built up grips for grip loss. General environmental control units Oromotor adaptive equipment

Static Position Maintenance Orthoses Common use in SCI, CVA Prevent contracture, maintain functional position of hand.

Interface technology for high cervical injuries Eye movement tracking Sip & puff Voice recognition

Eye Movements During Visual Scan Typical eye movement behavior while looking at a face - Note the extent to which fixations occur around the eyes - The eye movements are again voluntary and involve the saccadic system - People are generally not aware of these movements and as I have found later, verbal descriptions do not always agree with actual eye movement response. - The advantage of objective measurement techniques.

Eye Movement Measurement Techniques EOG Photoelectric Pupil Corneal Reflection Scleral Search Coil

Electrooculography (EOG) Cornea Positively Charged Relative to Retina - A Rotating Dipole

Contact Lens with Embedded Induction Coil Scleral Search Coil Contact Lens with Embedded Induction Coil

Infrared Reflectance Technique Photoelectric Infrared Reflectance Technique Limbus Eye Tracker

Pupil Corneal Reflection System “Dark Pupil” IR Image of the Eye Estimate of Pupil Center & Corneal Reflections “Original” Hockey Helmet System Mapping of Eye onto 2D CCD Array

Human-Machine Interfaces Visual control of movement, function or processes Visual control of systems from a remote location Combined Control

Protection Orthoses Skin protection PRAFO, multi-Podus – many brand names Not = heel pads, key is suspension of calcaneal posterior surface in space, no contact! Risk of Achilles tendon irritation