Your Seating Eval Notes Are Wrong: Fix Them
I read seating evaluation notes every week. Most of them contain at least one error that will show up in the finished chair — usually as a seat that's an inch too deep, a back that's two inches too tall, or a footrest position that dumps your weight onto your tailbone.
This isn't a knock on therapists. A seating eval is a lot of numbers taken in a short appointment, often on a mat table, often transcribed twice before anyone orders anything. Errors creep in. The problem is that once those numbers hit a purchase order, they become the chair you sit in for the next five years.
Here's how to catch the mistakes before they get built.
Get a copy of the actual measurements
Not the letter of medical necessity. Not the summary. The measurement sheet with the numbers on it. You're entitled to it, and any good therapist will hand it over without blinking. If someone gets cagey about giving you your own measurements, that tells you something.
What you want to see: seat width, seat depth (left and right, separately), back height, lower leg length (again, left and right), shoulder height, elbow height seated, and hip/knee/ankle range of motion.
The five errors I see most
1. Seat depth measured to the back of the knee, then used as-is.
Your seat depth measurement is popliteal fossa to posterior buttock — the back of the knee to your backside. But that's not your cushion depth. You need 1 to 2 inches of clearance behind the knee so the front edge of the cushion isn't pressing into the back of your calf and cutting off circulation. If your eval says "seat depth 18 inches" and the order says "18 inch seat depth," someone skipped a step.
Check: does the note distinguish measured depth from ordered depth? If not, ask.
2. Left and right treated as identical.
Most people are asymmetrical. A pelvic obliquity, a leg length discrepancy, a hip that doesn't flex past 85 degrees on one side — all common, all easy to miss when someone measures one leg and writes it down twice. I've seen clients with a genuine 3/4 inch leg length difference get two identical footrests, then spend two years wondering why they always slide toward one side.
Check: are there two numbers for lower leg length and seat depth, or one?
3. Back height measured while sitting on a mat table.
A mat table is flat and firm. Your cushion is not. If your therapist measured back height from the mat surface but your cushion compresses to 2.5 inches under load, your ordered back height is now 2.5 inches taller than intended relative to your body. For a manual chair user who propels, that difference is the gap between free shoulder movement and catching your scapula on the backrest every single stroke.
Check: does the note specify "measured on cushion" or list a cushion loaded height? If it just says "back height 16 inches," ask what surface that was from.
4. Hip flexion range not recorded.
If you can't flex your hips past 90 degrees, a standard 90 degree seat-to-back angle will force your pelvis into a posterior tilt — you'll slide forward, your lumbar spine will round, and you'll be building a pressure injury on your sacrum. This needs an open seat-to-back angle, and it needs to be in the notes.
Check: is there a hip flexion number at all? Blank fields are the most common error of all.
5. Weight and activity level pulled from an old chart.
Rear axle position, camber, and frame stiffness all get specified based on how you actually use the chair. If the note says "limited community ambulation" because that's what it said in 2019 and you now push six miles a day, you'll get a chair set up conservatively — axle too far back, seat-to-floor too high, and a push that fights you.
What to do with what you find
Don't argue with the therapist. Ask questions instead: "I noticed seat depth is a single number — should that be different left and right?" Nine times out of ten they'll catch it themselves and thank you.
Then, before anything is ordered, ask for a spec sheet — the actual configuration going to the manufacturer. Compare it line by line to the eval. Seat width, depth, back height, back angle, front seat height, rear seat height, axle position, camber, caster size. This is the last checkpoint. After this, changes cost money and months.
One honest tradeoff: some of these numbers genuinely can't be finalized on paper. Rear axle position in particular is a fit-and-adjust item — you want a chair ordered with adjustable axle plates so you can dial it in over the first few weeks. Don't let anyone talk you into a fixed-axle frame to save weight unless you already know exactly where your axle needs to be.
A seating eval is a starting point, not gospel. Read yours.
Ready for a Chair That Actually Fits?
Good measurements are only half the job — someone still has to turn them into a spec sheet that reflects how you actually live. That's the part I do.
I work directly with clients to specify and order custom ultra-lightweight wheelchairs — no middlemen, no upsells, just the chair that fits your life.
Get started at wheelchair.direct — answer a few questions and I'll reach out personally.