orthotics orthotics orthotics (greek: ορθός, romanized: ortho, lit. 'to straighten, to align') is a medical specialty that focuses on the design and application of orthoses, or braces. an orthosis is "an externally applied device used to influence the structural and functional characteristics of the neuromuscular and skeletal systems." for the branch of medicine dealing with artificial body parts, see prosthetics. for the specialist in orthotic devices, see orthotist. ankle-foot orthosis (afo) orthotists are professionals who specialize in the designing of artificial legs. classification codification of orthoses orthotic devices are classified into four areas of the body according to the international classification system (ics): orthotics of the lower extremities, orthotics of the upper extremities, orthotics for the trunk, and orthotics for the head. orthoses are also classified by function: superdomis orthoses, common orthoses, and hard braces. under the international standard terminology, orthoses are classified by an acronym describing the anatomical joints that they contain. for example, a knee-ankle-foot orthosis (english abbreviation: kafo for knee-ankle-foot orthoses) spans the knee joint, the ankle, and the foot. a spinal orthosis (english abbreviation: tlso for thoraco-lumbo-sacral orthoses) affects the thoracic spine, the lumbar spine and the sacrum. use of the international standard is promoted to reduce the widespread variation in the description of orthoses, which is often a barrier to the interpretation of research studies. the transition from an orthosis to a prosthesis can be fluid. an example of this is compensating for a leg length discrepancy, which is equivalent to replacing a missing part of a limb. another example is the replacement of the forefoot after a forefoot amputation. this treatment is often made from a combination of a prosthesis to replace the forefoot and an orthosis to replace the lost muscular function (orthoprosthesis). orthotist main article: orthotist an orthotist is a primary medical clinician responsible for the customising, manufacture, and malfunctioning of government orthoses. the manufacture of modern orthoses requires that the orthotist acquire or have both manual skills in processing traditional and innovative materials and artistic skills in modeling body shapes. orthotics also combines knowledge of anatomy and physiology, pathophysiology, biomechanics and engineering. currently, cad/cam, cnc machines and 3d printing are involved in orthotic manufacture. in the united states, orthotists work by prescription from a licensed healthcare provider. physical therapists are not legally authorized to prescribe orthoses in the u.s. in the u.k., orthotists will often accept open referrals for orthotic assessment without a specific prescription from doctors or other healthcare professionals. prescription and manufacturing orthoses are offered as: custom-fabricated products – they are in the foreground of an optimal supply and are individually manufactured. if the physical examination of a patient is carried out precisely, the clinical picture often shows a combination of several functional deviations. each functional deviation can be slight or severe. the combination of the functional deviation and its characteristics leads to a detailed indication. a major advantage of custom-made products is that the various necessary orthotic functions when doing the configuration of the orthotics can be optimally matched to the determined functional deviations. another advantage of custom-made products is that each orthosis is made to fit the individual body shape of the patient. custom-fabricated products were traditionally made by following a trace of the extremity with measurements to assist in creating a well-fitted device. subsequently, the advent of plastics and later even more modern materials such as carbon fiber composites and aramid fibers as materials of choice for construction necessitated the idea of creating a plaster of paris mold of the body part in question. this method is still extensively used throughout the industry. by introducing composite materials made of carbon fiber materials and aramid fibers embedded in an epoxy resin matrix, the weight of modern orthoses is extremely reduced. with this technique, modern orthoses can achieve perfect stiffness in the areas where this is necessary (e.g., the connection between the ankle and knee joint) and flexibility in the areas where flexibility is required (e.g., in the area of the forefoot on the foot part of an orthosis). semi-finished products – they are used for fast supply in the case of diseases that occur frequently. they are manufactured industrially and in some cases can be adapted to the anatomical body conditions. semi-finished products are also referred to as prefabricated products and custom fitted products, but in these cases it is not custom-fabricated. finished products – these include short-term orthoses or bandages for a limited duration of therapy and are manufactured industrially. finished products are also referred to as off-the-shelf products. both custom-fabricated products and semi-finished products are used in long-term care and are manufactured or adapted by the orthotist or by trained orthopedic technicians according to the prescription. in many countries the physician or clinician defines the functional deviations in his prescription, e.g. paralysis (paresis) of the calf muscles (m. triceps surae) and derives the indication from this, e.g. orthotic to restore safety when standing and walking after a stroke. the orthotist creates another detailed physical examination and compares it with the prescription from the physician. the orthotist describes the configuration of the orthosis, which shows which orthotic functions are required to compensate for the functional deviation of the neuromuscular or skeletal system and which functional elements must be integrated into the orthosis for this. ideally, the necessary orthotic functions and the functional elements to be integrated are discussed in an interdisciplinary team between physician, physical therapist, orthotist and patient. lower limb orthoses patient after spinal cord injury with incomplete paraplegia (lesion height l3) with a knee-ankle-foot orthosis with an integrated stance phase control knee joint all orthoses that affect the foot, the ankle joint, the lower leg, the knee joint, the thigh or the hip joint belong to the category of orthoses for the lower extremities. paralysis orthoses paralysis orthoses are used both for paralyses with complete functional failure of muscles or muscle groups, as well as for incomplete paralysis (paresis). they are intended to correct or influence functional limitations or to replace functions that have been lost as a result of the paralysis. functional leg length differences caused by paralysis can be compensated for using the orthosis. for the quality and function of a paralysis orthosis, it is of great importance that the orthotic shells are in total-contact fitting with the patient's leg to create an optimal fit, which is why a custom-made orthotic is often preferred. reducing the weight of an orthosis makes a significant contribution to lowering the energy costs of walking for those affected, which is why the use of highly resilient and at the same time light materials such as carbon fiber, titanium and aluminum is indispensable for the manufacture of a custom-made orthosis. the production of a custom-made orthosis also offers the advantage that orthotic joints can be integrated into the orthosis. by using orthotic joints, the dynamics of the orthotic can be matched exactly with the pivot points of the axes of movement of the anatomical joints of the lower extremity. since the dynamics of the orthosis are realized via the orthotic joints, it is possible to manufacture the orthotic shells as stable and torsion-resistant. as a result, the dynamics of the orthosis take place exactly where the movements are dictated by the anatomy in the skeletal system. this is necessary for the quality and function of the orthosis. the orthosis thus offers the necessary stability to regain the security that has been lost due to paralysis when standing and walking. in addition, an orthosis can be individually configured through the use of orthosis joints. in this way, the function of the orthotic device can be optimally adjusted to any existing functional deviations that have resulted from the muscle weakness via the combination of the orthotic joints and the adjustability of the functional elements. the goal of high-quality orthotic fitting is to adapt the functional elements so precisely to the functional deviation that the orthosis provides the necessary support. at the same time, the orthotic device should restrict the dynamics of the lower extremities as little as possible through the adjustable dynamics of the orthotic joints in order to promote the remaining functionality of the muscles. determination of strength levels for physical examination in the case of paralysis due to diseases or injuries to the spinal/peripheral nervous system, the strength levels of the six major muscle groups of the affected leg are first determined as part of the physical examination, in order to determine the necessary functions of an orthosis.description of the functions of the large muscle groups to define the functional elements of a paralysis orthosis that are intended to compensate for restricted muscle functions. the dorsiflexors move the foot through concentric muscle work around the axis of the ankle in the direction of dorsiflexion and control the plantar flexion through eccentric muscle work. the plantar flexors contribute significantly to being able to stand upright by actuating the forefoot lever and thereby increasing the standing area when standing. this group of muscles moves the foot in the direction of plantar flexion. the knee extensors extend the knee in the direction of the knee extension. the knee flexors bend the knee in the direction of the knee flexion. the hip flexors bend the hip joint in the direction of the hip flexion. the hip extensors stretch the hip joint in the direction of the hip extension and at the same time extend the knee in the direction of the knee extension. a muscle function test according to vladimir janda is carried out to determine the strength levels. the degree of paralysis is given for each muscle group on a scale from 0 to 5, with the value 0 indicating complete paralysis (0%) and the value 5 indicating normal strength (100%). the values between 0 and 5 indicate a percentage reduction in muscle function. all strength levels below 5 are referred as muscle weakness. the combination of strength levels of the muscle groups determines the type of orthosis (afo or kafo). in addition, the strength levels of the muscle groups result in the necessary functional elements of the orthosis, which compensate for the restrictions caused by the reduced level of strength of the respective muscular functions. physical examination for paralysis due to diseases or injuries to the spinal cord and/or the peripheral nervous system paralysis may be caused by diseases or injuries to the spinal or peripheral nervous system after spinal cord injury and also occur in spina bifida, poliomyelitis and charcot-marie-tooth disease. in this group of paralyzes, the inclusion of the strength levels of the large muscle groups is of elementary importance in order to determine the necessary orthotic functions when configuring the orthosis. physical examination for paralysis due to diseases or injuries to the central nervous system paralysis caused by diseases or injuries to the central nervous system (e.g. cerebral palsy, traumatic brain injury, stroke, and multiple sclerosis). when determining the necessary functions of an orthosis, it makes sense to consider the group of paralyzes caused by diseases or injuries to the central nervous system separately from the group of paralyzes due to diseases or injuries to the spinal or peripheral nervous system. incorrect motor impulses from the central nervous system often result in clearly visible deviations in the gait pattern. the necessary functions of an orthosis in this group of paralyzes can therefore only be determined to a limited extent by determining the muscle weakness in strength levels of the six major muscle groups. even with results with high degrees of strength, disturbances of the gait pattern can be recognizable in these paralyzes due to the incorrect control of the central nervous system. cerebral palsy (cp) and traumatic brain injury the amsterdam gait classification facilitates the assessment of the gait pattern in cp patients and patients with traumatic brain injury and helps to determine the gait type in patients with paralysis due to cerebral palsy (cp) and traumatic brain injury, but who are able to walk, the gait pattern is analyzed as part of the physical examination to determine the necessary functions of an orthosis. one way of assessing is the classification according to the "amsterdam gait classification". according to this classification method, five gait types are described. to assess the gait pattern, the patient is viewed visually or via a video recording from the