Properly sized crutches should allow a gap of two to three finger widths (about 1.5 to 2 inches) between the top pad and your armpit, with the handgrip positioned at wrist height. Getting this right matters more than most people realize. Crutches that are too tall press into the nerves under your arm, and crutches that are too short force you to hunch forward, straining your back and shoulders.
Sizing Underarm (Axillary) Crutches
Underarm crutches are the most common type, and they have two adjustment points: the overall height and the handgrip position. Start by standing upright in the shoes you’ll wear most often, with your arms relaxed at your sides.
For overall height, adjust the crutch so the top pad sits 1.5 to 2 inches below your armpit. An easy way to check: slide two or three fingers between the pad and your armpit. If your fingers fit comfortably, the height is right. If the pad touches your armpit when you stand straight, the crutch is too tall.
For the handgrip, adjust it so the grip lines up with the crease of your wrist when your arm hangs naturally by your side. When you grab the grip, your elbow should have a gentle bend, roughly 15 to 30 degrees. This slight bend lets your arms absorb your body weight efficiently without locking your elbows or fatiguing your shoulders. If your elbows are completely straight or bent too deeply, the handgrip needs repositioning.
Sizing Forearm (Elbow) Crutches
Forearm crutches wrap around your lower arm with a cuff and are common for longer-term use. They have two adjustment points as well: the cuff height and the handgrip height.
Set the handgrip at wrist crease height, just as you would with underarm crutches. The forearm cuff should sit 1 to 2 inches below the bend of your elbow. If the cuff is too high, it digs into your elbow joint. Too low, and it won’t stabilize your forearm properly. Your elbow should have a slight bend when gripping the handle, giving you control without straining your wrist or shoulder.
A Quick Sizing Estimate Before You Adjust
If you’re buying crutches before you can stand and fine-tune them, a common shortcut is to subtract 16 inches from your height. Someone who is 5’10” (70 inches) would start with crutches around 54 inches long. This gets you in the ballpark, but it’s only an estimate. Body proportions vary, so always do the standing adjustment described above once you have the crutches in hand.
Most adjustable crutches use push-button pins at set intervals. After sliding to the correct hole, make sure the pin clicks fully into place on both sides. A pin that’s only halfway seated can collapse under your weight.
Sizing Crutches for Children
The same principles apply, but kids outgrow their settings fast. With the child standing upright, you should be able to fit about one inch (two fingers) between the underarm and the top of the crutch. Handgrips go at wrist level, and elbows should be gently bent when holding the grips.
Check the adjustment screws every few days. They loosen easily with regular use, especially with active kids. Children also tend to lean on the armpit pads, which can cause rashes and compress the nerves in the upper arm. Remind them that their hands and arms carry the weight, not their armpits.
Why the Armpit Gap Matters
The space between the pad and your armpit isn’t just about comfort. A bundle of nerves runs through the underarm area, and sustained pressure on them can cause a condition sometimes called “crutch palsy.” Symptoms include numbness on the outer shoulder, shoulder pain, and weakness when trying to lift your arm away from your body. This is entirely preventable. Your body weight should always travel through your hands and wrists, never through the top pads pressing into your armpits. The pads are there for light guidance and stability, not load-bearing support.
Standing and Walking Position
Once your crutches are sized, how you position them on the ground affects your balance and safety. Stand with the crutch tips about 6 inches in front of your toes and 6 inches out to each side. This is called the tripod position, and it gives you a wide, stable base. Keeping the tips too close together or too far forward makes you wobbly and increases fall risk.
Look ahead when walking, not down at your feet. Keep your shoulders relaxed and avoid hunching. If you find yourself leaning forward significantly, the crutches may be too short.
Navigating Stairs Safely
Stairs require a specific sequence to stay safe. If a handrail is available, use it. Hold both crutches together in one hand (crossed for stability) and grip the rail with the other.
- Going up: Step up first with your good leg, then bring the crutches and your injured leg up to the same step. Think “good leg leads going up.”
- Going down: Place the crutches on the step below first, hold your injured leg out in front of you, then lower yourself down using your arms and good leg. Think “crutches and injured leg lead going down.”
Take one step at a time. Trying to skip steps or rush significantly increases fall risk, especially on the way down.
Weight Limits and Equipment Checks
Standard adult aluminum crutches typically support up to about 300 pounds. Bariatric models are available for higher weight capacities, with some rated up to 550 or 650 pounds. These are wider, reinforced, and use heavier-duty hardware. If you’re near the upper limit of a standard pair, switching to a bariatric model is worth the investment for safety.
Inspect your crutches regularly, especially the rubber tips. Worn-down tips with smooth tread become dangerously slippery on hard floors and wet surfaces. Replacement tips cost a few dollars at any pharmacy or medical supply store. Also check that all push-pin adjustments are still locked in position and that the armpit pads haven’t compressed to the point where they no longer cushion effectively. Foam pads flatten over time, and aftermarket gel or sheepskin covers can help if the stock pads wear thin.