Dr. Richard Bruno is Chairperson of the International Post-Polio Task Force and ex-Director of The Post-Polio Institute and International Centre for Post-Polio Education and Research at Englewood (NJ) Hospital and Medical Center.
His new book, The Polio Paradox: Uncovering the Hidden History of Polio to Understand and Treat "Post-Polio Syndrome" and Chronic Fatigue, will be published by Warner Books in June 2002.
Please e-mail questions directly to him firstname.lastname@example.org.
Note: This column is for information purposes only and is not intended as a substitute for professional medical advice.
Q: The knee on my polio leg kept bending further backward over the years. I was told to get a brace but didn't want one until I absolutely had to. My knee hurt so much I finally got a brace. But my knee bends so far back now that the brace bites into my skin and is so painful I can't wear it. Even if I could wear the brace, it is so heavy I can't lift my leg. What can I do?
A: Unfortunately, it's too late for a brace to help you. Braces are designed to support a weak leg, not to fix mechanical problems like recurvatum ("back knee"). We have seen many braces that hurt too much to wear because they were intended to "fix" recurvatum or to straighten a foot that has turned outward for 40 years. All braces should be designed to fit your leg just as it is, not to make it look the way other peoples' legs do.
Many polio survivors come to the Post-Polio Institute with braces that are unusable: They are too heavy because they are made with 1940s vintage steel or aluminum metal uprights, contain way too much plastic or have ankle joints. Our patients do very well with the new lightweight braces that use plastic that is molded to the shape of your foot and leg to replace the metal uprights. The most common brace worn by polio survivors is the short leg brace, known as the molded ankle-foot orthosis. It is made of relatively thin plastic that slips into your shoe and goes up the back or front of your lower leg to stop foot drop, give a spring to your step if you have weak calf muscles, and even support a weakened thigh muscle to help prevent the knee from buckling.
The brace you were prescribed, the long leg brace or knee-ankle-foot orthosis, usually replaces the metal uprights with molded plastic that slips into your shoe, goes up the back of your lower leg, and is attached to a plastic cuff behind your thigh with a metal hinge at the knee. Uprights can be used in place of plastic but are now made of graphite--a super-strong, ultra-lightweight but very expensive composite material used in airplanes--if you need extra support, or if your leg twists too much to be comfortable in a molded brace.
There are now two types of KAFO knee joints. The old familiar joint with drop-locks or a spring-loaded latch prevents the knee from bending when you stand and walk. A newer development, the offset joint, can be used by those who have some strength in their quadriceps and whose knees bend backward at least a little. The offset joint doesn't lock, but it still prevents the knee from bending when your leg is straight. With the offset joint you can swing your leg normally when you walk but be secure when you're standing.
However, polio survivors should avoid ankle joints--be they plastic or metal--that prevent your foot from dropping but allow your ankle to bend upward. Hinged ankles add weight to the brace, take away support for weakened thigh muscles and prevent the brace from helping your leg to spring forward.
I'm sorry a brace can't help you. We have unsuccessfully tried to brace other polio survivors with severe recurvatum. They, too, couldn't wear a KAFO because it hurt too much. Instead, they needed to use crutches or a wheelchair. Which raises two important points: Waiting until you're "ready" or until you "have to" before using an assistive device is waiting too long. And, even if you are willing and able to use a brace, you would also need to use a cane or crutches. How do you know which to use? The rule of thumb is: If you use a MAFO, you also need a cane; if you use a KAFO, you need two forearm crutches.
If you have a brace on one leg, a cane in the hand on the opposite side shifts your weight away from the weaker, braced leg. Using two forearm crutches with a KAFO takes the load off your stronger leg as well as overused hip and lower back muscles on both sides. But there's a problem. Canes and crutches put strain on your hands, arms and shoulders and can cause carpal tunnel syndrome and upper body pain and muscle weakness. How do you save your arms? By using a wheelchair, especially outside the house. But that's a topic we've already covered (PPS Forum, October 2002).
New Mobility Articles
México a la vanguardia en el Síndrome de Post Polio