Orthosis

Treatments used for various types of fractures are cast immobilization, traction, and internal fixation. A plaster or fiber glass cast is the most commonly used device for fracture treatment. Most broken bones heal successfiiUy once properly repositioned, ie, fixed in place via a cast. This type of cast or brace is known as an orthosis. It allows limited or controlled movement of nearby joints. This treatment is desirable for certain fractures. 

Mechanical pain and disability due to permanent joint deformities require joint orthosis. Long-term relief of pain and improvements of function have been achieved with total hip, knee, shoulder, wrist and multiple joint replacements. 

These injections can likewise enable patients to wear and use orthotic devices more effectively. Injection into the triceps surae musculature can improve the fit and function of an ankle-foot orthosis by preventing excessive plantar flexor spasticity from pistoning the foot out of the orthosis.49 Injections into severely spastic muscles can also increase patient comfort and ability to perform ADL and hygiene activities. Consider, for example, the patient with severe upper extremity flexor spasticity following a CVA. Local injection of botulinum toxin into the affected muscles may enable the patient to extend his or her elbow, wrist, and fingers, thereby allowing better hand cleansing, ability to dress, decreased pain, and so forth.7... 

Andrews, B.J., Barnett, R.W. et al. Rule-based control of a hybrid FES orthosis for assisting paraplegic locomotion, Awtomeciicfl 11 175-199,1989. 

Goldfarb, M. and W.K. Durfee, Design of a controlled-brake orthosis for FES-aided gait. IEEE Trans. Rehabil. Eng., 1996,4 13-24. 

Solomonov, M., Best, R.,Aguilar, E., Cetzee,T, D Ambrosia, R., andRarrata, R.V. (1997),Reciprocating gait orthosis powered with electrical muscle stimulation (RGO-2), Orthopedics, pp. 315-324 (Part 1) pp. 411 18 (Part 2). 

Davis, R., Houdayer, T., Andrews, B., Emmons, S., and Patrick, P. Paraplegia prolonged closed loop standing with implanted nucleus FES-22 stimulator and andrews foot-ankle orthosis. Stereotaa. Funct. Neurosurg. 1997 69 281-287. 

Motion data collection subject calibration and multiple walks, per test condition (barefoot and orthosis)... 

A rehabilitation engineer asks three key questions Can a diminished function or sense be successfully augmented Is there a substitute way to return the function or to restore a sense And is the solution appropriate and cost-effective These questions give rise to two important rehabilitation concepts orthot-ics and prosthetics. An orthosis is an appliance that aids an existing function. A prosthesis provides a substitute. 

Orthosis A modality-specific appHance that aids the performance of a function or movement by augmenting or assisting the residual capabilities of that function or movement. An orthopaedic brace is an orthosis. 

An orthopedic prosthesis is an internal or external device that replaces lost parts or functions of the neuroskeletomotor system. In contrast, a orthopedic orthosis is a device that augments a function of the skeletomotor system by controlling motion or altering the shape of body tissue. For example, an artificial leg or hand is a prosthesis, whereas a calliper (or brace) is an orthosis. This chapter addresses only orthoses and external orthopedic prostheses internal orthopedic prostheses, such as artificial joints, are a subject on their own. 

FIGURE 68.1 Three-force system required in an orthosis to control a valgus hindfoot due to weakness in the hindfoot supinators. 

FIGURE 68.2 The ARGO reciprocating-gait orthosis, normally worn under the clothing, with structural components produced from 3D CAD. (Courtesy of Hugh Steeper, Ltd., U.K.)... 

Leg cuffs fitted snuggly with knee extended, but with orthosis/knee centers of rotation misaligned... 

Rectified, rectification Adjustment of a model of body shape to achieve a desirable load distribution in a custom-molded prosthesis or orthosis. 

Here we present technical aspects of the available externally powered orthoses and prostheses that interface directly or indirectly with the human neuro-musculo-skeletal system. We elaborate here two methods for the restoration of movements in humans with paralysis functional activation of paralyzed muscles termed functional electrical stimulation (FES) or functional neuromuscular stimulation (FNS or NMS), and parallel application of FES and a mechanical orthosis called hybrid assistive system (HAS). We also describe externally controlled and powered leg and arm/hand prostheses. 

Bionic glove was beneficial for tetraplegic patients both therapeutically and as an orthosis, yet, the overall acceptance rate remained insufficient. 

Hybrid assistive systems Combination of a functional electrical stimulation and a mechanical orthosis. Myoelectric (EMG) control Use of voluntary generated myoelectric activity as control signals for an externally controlled and powered assistive system. 

Reciprocating gait orthosis A walking and standing assistive system with a reciprocating mechanism for hip joints, which extends the contralateral hip when the ipsilateral hip is flexed. 

Self-fitting modular orthosis A modular, self-fitting, mechanical orthosis with a soft interface between human body and the orthosis. 

Ijzerman, M., Stolfers, T. et al., The NESS Handmaster orthosis restoration of hand function in C5 and stroke patients by means of electrical stimulation, J. Rehab. Sci. 9 86-89,1996. 

Andrews, B.J., Baxendale, R.H. et al, Hybrid FES orthosis incorporating closed loop control and sensory feedback,/. Biomed. Engng. 10 189-195,1988. 

Solomonow, M., Biomechanics and physiology of a practical powered walking orthosis for paraplegics. In Stein, R.B., Peckham, H.P., and Popovid, D. (Eds.) Neural Prostheses Replacing Motor Function After Disease or Disability, Oxford University Press, New York, pp. 202-230,1992. 

Houdayer, T., Davis, R. et al.. Prolonged closed-loop standing in paraplegia with implanted cochlear FES-22 stimulator and Andrews ankle-foot orthosis. In Popovid, D. (Ed.) Proceedings of 2nd International Symposium on FES, Burnaby, pp. 168-169,1997. 

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