Orthoses and prosthetics are two types of medical devices. While they share certain characteristics, they perform completely different functions. Orthoses are primarily designed to support a body part, while prosthetics are designed to replace a missing body part. A healthcare professional may also prescribe or provide any of the devices. Knowing how orthoses and prosthetics differ from each other can help make it easier to choose the right device.
Orthoses, from the Greek word "ortho" meaning "to straighten," are devices that correct or support the movement, shape, or function of a body part, including the torso, limbs, and extremities. The most common types are back braces, knee and foot braces, and shoe inserts. Most of these devices are used to help correct problems resulting from a health condition or injury. Scoliosis, a curvature of the spine, is often treated with a back brace. Orthotics can help improve posture and reduce back, leg, and foot pain by helping to force the skeleton into proper alignment.
Other types of braces include halo braces, which are used to immobilize the upper spine and head after spinal cord injuries, ankle braces, and hip braces. Orthoses also include flexible braces, for joints such as the knee and elbow, that are used to help prevent injury during athletics and other strenuous physical activities.
Prosthetics are medical devices designed to replace a missing or missing body part, and have been used for centuries. An example of the most primitive form of this device is the peg leg, often seen in movies. Modern prosthetics is a very advanced field with devices capable of performing many tasks. A prosthetic hand, for example, can detect micro-movements of the muscles in the remaining portion of the damaged limb and use these impulses to close a robotic hand, allowing the patient to grasp and manipulate objects.
In addition to their practical function, prosthetic devices can also be cosmetic. Prosthetic eyes serve a cosmetic function for patients who have lost an eye, and prosthetic limbs can help people who have lost one or both legs to walk or even run again. Advanced prosthetic legs designed with Kevlar and carbon fiber springs allow some athletes to run at near-Olympic levels. Equipped with a prosthetic arm, a patient can return to the workforce, perform everyday tasks, or enjoy hobbies and other activities that would be extremely difficult or impossible without the device.
Although orthoses and prosthetics differ primarily in their function, they are often constructed using some of the same materials. Advanced plastics, Kevlar, neoprene rubber, and nylon are common components of both types of devices. Strong light metals like aluminum and titanium are becoming more common in these devices, replacing much heavier steel. Both orthoses and prosthetics are best used under the supervision of a qualified healthcare professional to determine the best type of device for a particular use or patient.