The following are the responses to my post on 4/13/11, regarding a bent knee prosthesis:
Cast at 90 degrees, pad the kneeling surface with urethane or gel, straps to hold it together, knee-disarticulation knee and whatever foot is best. Works very well. Outside joints don’t.
Lane Ferrin CP
I had a patient like this that was able to walk in a pin suspension system with the foot offset anterior. It wasn’t very cosmetic but it worked with a very flexible foot. Hopefully he’s stretching because he may be able to resolve some of it with proper PT. Good luck!
Christie Ferraro
Attached is a prosthesis that I made for a patient of mine with a 65 degree FC. I used a PTB style socket with a 6mm silicone liner to help absorb some of the weight pressure on the anterior tibia. I used a carbon fiber flexion contracture plate (Flexcon by Prosthetic Design Inc.) and reversed it. The pyramid received is also slanted (maybe from Ossur). It is going to take a lot of therapy, at least for my patient. Hope this helps. Let me know if you need anything else.
Brad Poziembo
Some years ago I had a similar patient presented with about 55 degree
contracture. I cast him in a relaxed position for a PTB, using modular
construction, with a patella cuff suspension.
Care must be taken in positioning the socket adaptor beneath the socket, I
used and Otto Bock 4R42 socket adaptor.
The patient, after gait training, ended up utilising the prosthetic for
extended periods on a daily basis. Over time flexion contracture was reduced
by about 10%.
His big complaint was wearing long pants, as he was a lawyer and had to
appear in court, his appearance was a concern of his. I did not care, as I
did not expect any success at all. He eventually had zip in gussets fitted
to his work pants, and used short pants at home and on weekends.
Prior to this prosthetic, he was using a Cromwell Kneeler type prosthetic on
weekends, and using crutches during the day.
Hope this is of some help.
Peter A Lewis CCPO
I would go for a PTB/BK prosthesis with the flexion built into the socket and let him walk with it as he has some range and he may walk out a bit of the contracture and you can modify prosthesis to keep up with it. It will however stick out a bit when he sits but I think this is a better set up than a kneeling prosthesis.
My 2c
Andrew Cox
Bulldog tools makes plates for varying degrees of contractures. They work
very well as recently I did a bl-lateral with 64 deg contracture on one side
and 70 deg on the other. He did fine and over time has worked out some of
the contractures.
http://www.bulldogtools.com/category369_386/default.html?osCsid=fe4108e365a6
4c3a14ab8cb8c7ef0f45
Jeremy Sprouse
We had a patient bring one by our office, fabricated at Shriniers in St.
Louis, to see if we could fix the hinges and his was designed with a thigh
shell, BK socket, Otto Bock Prosthetics knee hinges like you would see on a
KAFO with the pyramid located one third of the way up the socket which was
the center line. As unfortunate as it is, he had no insurance and even
though I gave him a really discounted price to get him back in the work
force he could not afford it. He wanted to go back to work but could not
without the prosthesis so he is now a 20 year old welfare recipient. What a
shame!
Fred Wallace, L.C.O.
I just delivered a prosthesis for a patient with a 45 degree knee flexion contracture. I have done few over the years. I use OTS orthotic step lock joints to allow progressive stretching into extension while augmenting the quads in standing. I’ve used a bail lock or a trigger lock for release. I usually fabricate a flexible inner liner with a frame for the socket to allow adjustments and relief because the patient is effectively weight bearing on the tibia. I align it first on a slide and then finish it. A single axis foot can help with providing a knee extension force. The shoes may need to be modified with a rocker bottom.
My colleague, Brian, will send you some photos tomorrow.
Let me know if you have any other questions.
Kelly M. Lee, CP
You take two under arm crutches fashion them together so that you have medial,lateral and anterior uprights. Of course you must cut off the crutches proximally. Then create a cradle for the bent knee out of just about ant thing like closed cell foam, leather, or a go with a composite. attach straps of your choice, and finally adjust the height. You could go with casting and make an all composite device as well. AHRRR now he be ready for the pirate festival. Or the low back pain clinic from all the hip hiking and circumduction.
There is one prefabricated by some manufacturer, I just can not remember who.
But I would talk the guy into a revision if at all possible. KNEE SchMEE if it ain’t workin’ get rid of it. My prosthetic knee works really well.
James O. Young Jr., LP, CP, FAAOP
