This post is for lower limb loss/difference, so if it doesn’t pertain to your uniqueness, go have a beer, take a nap, or do something fun!
Insurance companies require a quantitative evaluation from a medical professional, a prosthetist, or a PT before they will pay the typical 80% of your DME (Durable Medical Equipment) costs for a prosthesis. For the purpose of this post,I will use PT – easier to type. Regardless of who evaluates you, that info goes to your insurance company along with the PT’s recommendation for what kind of components you need. Prosthetists also take into consideration what your budget is. That 20% can be a big chunk of money.
That quantitative evaluation is called the AmpPro/AmpnoPro. It is a list of tasks you are required to perform to the best of your ability. If you have a prosthesis, you are evaluated by the AmpPro scale. If you do the evaluation without a prosthesis, you are evaluated by the AmpnoPro scale. The tasks you must perform are identical.
The score you receive (and its implications) has many faults. First, the evaluation of some of the tasks are somewhat subjective and the scoring depends on the evaluator’s opinion of how well (or not) you accomplish said task. The difference in a few points can make a difference in your score, which equates to different components that your insurance company will approve.
Second, I believe that the test does not completely give an overall picture of the amputee’s prosthetic needs. It is one tool in the toolbox. A good PT will know the patient as a person, not just as an amputee. A person who wants a prosthesis for daily living skills is not the same as a person who wants to hike, bike, swim, fish, bowl, or return to a physically demanding job, or who wants to compete at a paralympic level. The AmpPro/Amp No Pro does not take this into consideration as far as the tasks are concerned.
Third, the eval is incredibly outdated, and this is truly the crux of why I believe it needs to be revamped and brought into the 21st century. The result of the eval is called a K-level, so if you’ve heard that term, it is the result of your Amp Pro/AmpnoPro test. Your PT will send your eval and K-level recommendation to your prosthetist, who will then build your leg to that specific K-level, also taking into consideration your 20% DME budget. There are only 5 K-levels. 0 is for those whom a prosthesis would not be recommended or who would only use it to transfer more safely than without one, up to 4, which is elite athlete status. Phew!
I have been an LBKA for 3 ½ years, and in that time, I have had 3 legs built for me. The first time I did the test, my PT really didn’t explain it well, and I really didn’t get it. I took the AmpnoPro (obviously) and received a K-1 eval. Got my leg and named her RHO (story for another time). It was a very basic pin-lock with a very basic foot – very little ankle movement, for stability, I was told. Six months later, I took the test again and bumped up to K- 2 — WooHoo! My residual limb had shrunk enough that I decided on an entire new prosthesis instead of just switching the foot. RHO2 had more ankle flexibility. In September 2020 I found a new prosthetist as I was ready for a new set of eyes. My friends thought I might be able to shed a corset that was attached to it that encased my entire upper thigh and to get a more advanced leg. They were right. I took the test again and made it to the lower end of the K-3 range. This bumped me up to a far more advanced foot with a hydraulic assist to help me with inclines/declines. What a difference! With a great amount of PT, I was able to go to a suction system instead of a pin-lock and shed both the corset (and its weight) and a knee brace I wore on my sound leg. Fortunately, I was able to pay for the 20% DME, as it was twice the price of my other two legs.
When you are evaluated, you receive a score – as you can see, each K-level has a range:
If you look carefully, the AMPnoPRO test assumes that if you are a K1, you will have a score of at least 9. A score below 9 means that the prosthesis will be used for safe transfer only and is not intended for ambulation. If you have a prosthesis, the test is designed so that you will accrue a minimum of 15 points.
One task is “stepping over an object that is 4 inches high. 0=unable to do, 1=catches foot, interrupts stride, and 3=steps over without interrupting stride.” If you score a 1, which reason is it? Catches foot, interrupts stride, or both? Also, how wide is the object? Stepping over a 4 inch branch on a walking path would be different than having to step over something wider, like a parking lot berm. Who decided that 4 inches was the magical number? The only way I can successfully do this is if I pace my steps so that I start with my amputee side, use my hip to gain the height, and follow through with my sound side. I fail 100% of the time if I step over with my sound foot first. But because I was able to do it in a very structured and controlled environment, I scored a 3. Would that transfer to a real life situation? I think not.
K-levels need to be brought into the 21st Century. Although you can’t see it in my profile pic, I am physically not able to walk without aids (yay for SideStyx!). And yet my current AmpPro score? 42! I do consider myself athletic, maybe an amateur athlete, but certainly not an elite athlete. And yet, I am now only 1 point away from K-4 status; at the very least there should be more K-levels.
Here’s another task that doesn’t translate well into real world experience: “Arises from a chair – Ask the patient to fold arms across chest and stand. If unable to, use arms or assistive device.” How often do able-bodied people stand up with their arms crossed over their chest? Chairs have arms for a reason. And, if you use your arms or an assistive device, you get fewer points. The test has other tasks that evaluate balance. I see this more of a strength and coordination task.
One or two points can make a difference between what your insurance will cover. I fully admit that any kind of test like this cannot be 100% objective, but I do believe improvements must be made that will better align the tasks on the test with the technology of today.
I look forward to sharing with you the ongoing work relating to updating K-levels by Principal Researcher Brian Hafner out of the University of Washington. Some of you, like me, may have been a willing “lab rat” for the physical tasks they believe are more up-to-date. Stay tuned for
“AmpPro, AmpnoPro, K-levels, and Insurance–OH MY! (Part 2)” – it was a fascinating (Mr. Spock!) interview!
My sincere thanks to Danielle Potter-Dube, my PT for the last 2 years (aka “ The Dragonslayer”) from Northeast Rehabilitation in southern NH, and to Cosi Belloso, who runs her own PT clinic for amputees in Tampa, Florida.
And remember: you don’t know how much strength you have until you are called upon to use it.
Beth Hudson, LBKA
Danielle Potter-Dube PT, DPT
Cosi Belloso MSPT