Thanks to all who responded. The list serve proves again to be an excellent
source of peer knowledge Here is my original post and the responses, which
includes a response from a manufacturer. I did not want to summarize the
responses as I thought the opinions were just as important as the specific
knee recommendations.
> ORIGINAL POST:
> I am hoping this request will reach those of you who have patients in the
> farming community. I have a patient of average height and weight, who is a
> crop farmer. He presents with a knee disarticulation. We are starting to
> discuss beginning a new prosthesis and options for knee units. It is
> difficult for the patient to get into the office due to his busy
> schedule, so he generally is opposed to any component that is considered
> “high maintenance” He has been pleased with his current polycentric
> friction knee, as it has been quite durable and dependable over the past 5
> years. He would like the option to lock out the knee when completing
> certain tasks on the farm. I’m looking for any feedback, both positive or
> negative, on knees you have used on a patient with this level of activity..
> Thanks in advance
>
> RESPONSES:
1. Check out Medi. Their knees are more durable than most, and I use them
a lot for the same scenarios. I have a lot oil well patients and
farmers.
The OFM2 is the friction knee with a manual lock. If you want to change
to a 4bar with extension assist and a manual lock, the OFM1SF us a good
option. It may work better for clearance as well however it is a heavier
knee joint.
2. SNS unit works very well.
3. As a very active AKA, I would recommend the Aulie knee, very durable and
virtually indestructible nylon kneee. I use it for all gardening activates,
road and mtn biking, beach activities and when away on vacations. The knee
easily be locked out.
4. I have the same 45 year old farmer patient that I rarely see. I fitted
him with a DAW graphlite pneumatic 4-bar knee in the past that has been very
solid. He used the same knee before with over 10 years of use and only one
rebuild. I think they also offer some knees with manual lock options. I
hope this info is helpful to you.
5. Difficult call. The locking knee aspect of what he wants is what
presents
the problem. As I recall, Otto-Bock does have a cable actuated knee that is
otherwise basically a safety knee. The cable mounts along the wall of the
socket, so he can simply reach down and unlock the knee. The problem??? It
locks every time the knee is fully extended. Call Otto-Bock and talk to them
about this (Model #3R33). They may have other ideas or options for you.
Want to really piss off your patient??? Put him in an Ossur Total Knee. Yes,
technically it does lock, but if you shift your weight and accidently load
the toe, the lock turns off. Then, when he goes to shift his weight, the leg
will buckle underneath him. I’m guessing that you will get more than one
response suggesting this knee. Trust me that this knee is neither simple,
predictable, nor inexpensive.
Finally, check the Daw catalog. I seldom use their products, but it seems
like they may have a product similar to Otto-Bocks, and perhaps one with a
lock that can be totally disengaged for normal ambulation. They may even
have one in a four bar design that would be more suitable for a knee
disarticulation.
6. The only knee I would recommend would be the AULIE KNEE by Aulie
Prosthetic Devices.
Is not necessarily the best knee for a disartic if cosmetics is an issue,
however it is the most durable and low maintenance knee unit I have ever
used. It is a single axis with hydraulic cylinder. Guaranteed to be totally
water, mud, grease, etc… proof. It also has a stainless steel rod to
insert to lock it out in full extension. If He does not mind the knees being
level, it’s perfect for his application.
The web site is, www.auliedevices.com Phone # 541-548-7355.
7. It would be interesting to know what knee your pt is currently
on…Habermenn (3R36)? If so, and your patient is sensible, you could
provide him with an Allen key to set the stability high himself.
Perhaps consider Otto Bock hydraulic 3R55 – does not lock but it could
be set very stable. Another knee without a lock but may be worth
considering – Total knee. Medi NFM1/NOFM1 (polycentric with lock).
Although the latter is mobility medium.
8. medi OFM1 would probably do this man well. its a polycentric knee with
the option of having it totally free or HOKL/SAKL. The HOKL option would
probably be best as it can be left free kneed when he wants or locked when
he wants.
9. I asked about service connection because service connected Veterans are
eligible for a second prosthesis.
That limb can be dedicated for occupation or sports activities. This would
have given you the opportunity to try two different knee systems.
Teh Lin (the Taiwanese Manufacturer) had four bar knees that have an
optional lock mechanism. I have used them and they were robust.
10. Endolite 4 bar with the hydraulic unit. Functions like a mauch, but
with polycentric 4 bar and a correct knee center for long limb. Can bolt
direct on bottom of socket if you want.
11. Maybe its not the knee, but a foot change. Not sure what foot you
are using, but a foot with significant plantar flexion movement may keep the
knee in an extension moment and the center of knee rotation will be
maintained posterior to weight line. Just a thought.
12. I could recommend our 3A2000 hydraulic unit- it has options for knee
disarticulation:
3A2200 that is threaded for 3-arm adapter
3A2100 that is threaded for a 4-arm adapter
3A2100 for 4 Arm Adapter3A2200 for 3 Arm Adapter
We do have a loaner program for this knee and it has a MAX WEIGHT of 330lbs..
(K3-K4)
OR I could recommend a regular 4-bar knee-
3A30 – Modular 4-Bar Linkage Knee Joint – Titanium
– for knee disarticulation
– polycentric
– with mechanical extension assist
– suitable for max. 125 kg body weight
Recommendation:
– for knee disarticulation amputees
– with medium functional level (k1-k2)
– normal stability
– not suitable for insecure amputees and those with higher activity levels
Description:
The upper joint section with adjustment core and the lower joint section
with pyramid are connected to each other with anterior and posterior linkage
bars. The lamination anchor is the detachable connection to the socket. The
stance phase stability is achieved through polycentric kinematics. Extension
assist and axial friction are both adjustable.
Technical Data:
– Knee flexion range: approx. 110°
– Head height (knee center – upper edge): 18 mm
Accessory:
– Use Cosmetic Soft Foam Cover 60A47
MaterialWeightEff. HeightmKOrder-No.
Titanium657g120mm125kg (275LBS)3A30/T
3A21 – Modular 4-Bar Linkage Knee Joint – Stainless Steel
– for knee disarticulation
– with medium functional level (k1-k2)
– polycentric
– with mechanical extension assist
– suitable for max. 125 kg body weight
Recommendation / Function:
– identical in construction to 3A30
Technical Data:
– Knee flexion range: approx. 110°
– Head height (knee center – upper edge): 18 mm
Accessory:
– Use Cosmetic Soft Foam Cover 60A47
MaterialWeightEff. HeightmKOrder-No.
Stainl Steel870g120mm125kg3A21/S
I WOULD recommend the KINEGEN Stream- ONLY because the K-level is higher for
this patient, the other 2 knees that I have available for
knee-disarticulation are K1-K2 and the others are recommended only for K1-
so this wouldn’t work.
>
