Major Technological Advances in Knee-Ankle-Foot (KAFO's) Orthoses

For the past 40 years, patients who wear long leg braces (KAFO's) have essentially had two options for knee joints. In a choice between the lesser of two evils, your knee could either be locked up all the time, forcing you to walk stiff legged, or your knee could be unlocked, allowing you to swing your leg through more easily. However, the "free knee" (unlocked) knee joint was not capable of preventing the knee from buckling, which is frequently the very reason a person may need this kind of brace.

Today, through major technological advances, that is all changing. Long leg braces are now available, through SCOPe, that lock when you need them at stance phase, and unlock when you want them to at swing phase. This simple sounding, but remarkable innovation results in a smoother gait that requires less energy while walking.

Examples of this technology include "the E-Knee", "Horton KAFO", the Free Walk/UTX KAFO, and the Bosko Knee Joint.

The E-Knee

The "E-Knee", with the "E" standing for "electronic", joint represents the first practical marriage of the computer age with long leg braces. The E-Knee combines force plates and microprocessor technology to create a knee joint that locks and unlocks with foot contact on the floor. The locking mechanism is on the outside of the knee joint and is powered by a lithium battery. The joint also utilizes a unique clutch lock, which will lock in any position when triggered. The knee joint is linked to a footplate, which contains multiple sensors. Through a careful calibration process the foot-plate/knee joint mechanism is programmed to lock at the proper time, when the foot touches the ground. It is then further programmed to unlock the knee and allow for free swing as your gait cycle progresses.

Are you a candidate for this innovative technology? Your SCOPe practitioner will evaluate your diagnosis, muscle strength, and range of motion and discuss with you, based on findings, whether your needs and conditions create an appropriate match with the new device.

People with such diagnoses as Polio, spinal cord injury, multiple sclerosis, stroke, Femoral Nerve Palsy, and diabetes are usually good candidates for this type of bracing. While many other bracing systems require varying amounts of hip, knee, or foot and ankle function before they can work, the E-Knee works well for people who have weakness, up to and including a flail hip.

One of the most important features of this breakthrough technology is the joint's ability to lock at any point. The weight bearing is started through the foot. This feature means your knee does not have to be completely straight in order to lock – a very important feature in the event of a stumble, which hopefully prevents a fall.

The UTX/Free Walk KAFO

This innovative design combines ultra lightweight materials, a low profile, and maximum control for the wearer. The brace is manufactured from tubular stainless steel, whose hollow design creates a very strong but extremely lightweight device (typically weighing in at only 28-32 oz). The UTX/Free Walk KAFO is the lightest on the market, making its unique single upright design close-fitting and very comfortable to wear.

What is truly exceptional about this brace is the ability of the knee joint to lock during stance phase, and then unlock during swing phase. This breakthrough is achieved through a cable linkage that connects the foot and ankle joint to the knee joint through the hollow upright. Orthotic patients have been asking for this kind of technology for years, and now, after thousands of patients have successfully used this device in Europe, at last it is available in North America.

As with all types of braces, this system is appropriate for some patients more than others. The ideal patient for this brace has muscle control at the hip or knee. Furthermore, there are other requirements that your SCOPe practitioner can explain to you when he or she evaluates you. This brace is best for patients who, for a variety of reasons, have problems with their knee buckling forward while standing and walking. The diagnoses associated with this problem frequently include spinal cord injury, polio femoral nerve palsy, MS, diabetes, lumbar plexopathy and stroke.

The SPL (Stance Phase Lock) by Bosko:

This joint represents another breakthrough in design and function. Its purpose is to lock the knee while in stance phase. However, as the knee becomes unweighted through "toe-off," the locking mechanism releases, and the knee is free to bend.

The locking mechanism is housed in the outside knee joint and works through a combination of gravity and muscle power. Gravity affects this particular knee joint through a fascinating pendulum type design; the pendulum tips forward and back, depending on where the knee joint is positioned in space, when the knee is in front of you while stepping forward. The pendulum slips back, locking the knee, at full extension. If the leg is behind you, as you prepare to take a step the pendulum slips forward. A slight knee hyperextension thrust and this pendulum forward position unlock the knee to allow free swing.

Similar in function to the free walk and UTX, the SPL brace requires a certain amount of hip control to function. Unlike the free walk and UTX, however, the SPL knee is completely independent of the foot and ankle, not requiring any motion in this joint to function.

Your SCOPe practitioner will work with you to be sure you choose the bracing and knee joint combination that best serves your needs. The SPL (stance phase lock) is designed for people who have lower extremity weakness resulting in knee buckling. Diagnoses related to this problem might include diabetes, stroke, spinal cord injury, polio, M-S, femoral nerve palsy, and lumbar plexopathy.