Putting on a below-the-knee prosthetic leg follows a consistent routine: inspect your residual limb, roll on your liner, add any necessary socks, and slide into the socket until the suspension system locks. The exact steps vary depending on whether your prosthesis uses a pin-lock, suction, or vacuum suspension system, but the preparation is the same for all of them.
Check Your Skin Before Every Use
Before you touch your liner, take a moment to look over your residual limb. You’re checking for redness, blisters, swelling, sores, or any sign of skin breakdown. If you have reduced sensation from diabetes or another condition, this step is especially important because you may not feel a problem developing. Most people should do this check at least once a day, but if you have any sensory impairment, check every time you remove the prosthesis.
Wash your residual limb with a mild soap and rinse thoroughly twice a day, morning and evening. If you tend to sweat heavily, wash more often and ask your prosthetist about antiperspirant products made specifically for amputees. Moisture trapped between your skin and the liner is one of the fastest routes to irritation and breakdown.
Rolling On the Liner
Your silicone or gel liner is the cushioned sleeve that sits directly against your skin. Start by turning it completely inside out. Place the closed bottom end against the tip of your residual limb, then slowly roll it up and over the limb until it sits fully in place. Think of it like rolling on a thick compression stocking from the bottom up.
Once it’s on, run your hands over the surface and feel for wrinkles, folds, or trapped air bubbles. Even a small fold can create a pressure point that turns into a blister after a few hours of walking. If something feels off, peel the liner back and re-roll it. A helpful trick: spray a light mist of rubbing alcohol on the outside of the liner (not the skin side) before rolling. This reduces friction and lets the liner glide into position much more smoothly.
Adding Prosthetic Socks
Your residual limb changes volume throughout the day and over weeks and months. Prosthetic socks, worn over the liner, let you fine-tune the fit inside the socket. Your prosthetist will tell you how many “ply” (layers of thickness) to start with, and you’ll learn to add or remove socks as your limb swells or shrinks.
When you pull a sock on over the liner, feel the bottom to make sure the fabric sits snug against the liner’s surface with no bunching. A loose sock can get pulled into the locking mechanism at the bottom of the socket, which jams the system and makes it difficult to get a secure connection.
Donning a Pin-Lock Prosthesis
Pin-lock systems are one of the most common suspension types for below-the-knee prosthetics. Your liner has a small metal pin sticking out from the bottom. The socket has a shuttle lock inside that grabs and holds that pin.
Sit down in a sturdy chair with the prosthesis on the floor in front of you. Slide your limb about halfway into the socket, keeping the pin roughly centered so it lines up with the lock opening at the bottom. Then either stand up on the leg or press down firmly on your knee. You should hear a distinct clicking sound. That click means the pin has engaged the lock and the prosthesis is secure.
If you don’t hear a click, don’t force it. Pull the prosthesis off and try again, making sure the pin is tracking straight down the center line of the socket. If it still won’t click after a few attempts, check that the pin is properly aligned with the natural center of your residual limb and that no sock material has bunched up near the lock.
To remove the prosthesis later, you’ll press a release button on the outside of the socket (usually near the bottom or back) that disengages the shuttle lock, then slide your limb out.
Donning a Suction Prosthesis
Suction sockets hold on by creating an airtight seal between the liner and the inner wall of the socket. There’s no pin involved. Instead, you rely on negative pressure (a partial vacuum) to keep the leg in place.
After your liner and socks are on, slide your residual limb into the socket. Then roll the suspension sleeve, a thick rubber or silicone band attached to the top of the socket, up and over your knee and onto your thigh. This sleeve is what creates and maintains the seal. Make sure it lies flat against your skin with no gaps or rolled edges, because any air leak breaks the suction and the prosthesis will feel loose or start to slip.
Some suction systems use a one-way valve at the bottom of the socket. As you push your limb in, air escapes through the valve but can’t re-enter, which pulls the socket tight against your limb. If you feel the fit loosening during the day, it usually means the sleeve has shifted or your limb volume has changed.
Donning a Vacuum Prosthesis
Vacuum systems work on the same principle as suction but use a mechanical or electronic pump to actively pull air out of the socket. This creates a stronger, more consistent hold and can reduce the natural volume changes in your residual limb throughout the day.
The donning steps for your liner, socks, and initial socket entry are the same as with suction. The difference comes after you’re in the socket: you activate the pump. On electronic systems like the WillowWood LimbLogic, you press the power button once on the pump (one beep confirms it’s on), then activate the wireless remote and hold the center button until the display shows the current vacuum level. The pump then runs automatically, pulling the socket to a preset pressure and maintaining it as you walk.
If the pump detects an air leak, it will beep rapidly (about ten times) and a red indicator light will turn on. This means the seal has broken. When that happens, restart the pump. If the leak persists, take the prosthesis off and re-don it, paying close attention to the sleeve seal and making sure no wrinkles in the liner or socks are letting air in.
Getting the Fit Right Day to Day
A well-fitting prosthesis should feel snug without pinching. When you stand, your body weight should distribute evenly across the socket, and you shouldn’t feel the bottom of your residual limb pressing hard against the end of the socket (called “bottoming out”). If you feel concentrated pressure on one spot, something is off with sock thickness, liner position, or limb volume.
Your residual limb will be larger in the morning and may shrink as you’re active during the day, especially in the first year or two after amputation. Many people start the morning with fewer sock ply and add a layer in the afternoon as their limb gets smaller and the socket starts to feel loose. You’ll develop a feel for this over time. A loose socket that pistons (slides up and down as you walk) causes friction and skin problems. A socket that’s too tight restricts circulation and creates pressure sores.
If you notice persistent redness that doesn’t fade within 15 to 20 minutes after removing the prosthesis, or if you see blisters, open sores, or any discharge, that’s a sign something in your fit or donning technique needs adjustment. Your prosthetist can modify the socket or help you troubleshoot your routine.
Common Mistakes to Avoid
- Rushing the liner roll. A wrinkled liner is the single most common cause of discomfort. Take the extra ten seconds to smooth it out.
- Skipping the skin check. Small problems become big ones fast inside a sealed socket. A red spot today is a blister tomorrow.
- Forcing the pin. If the pin won’t click, the alignment is off. Forcing it can damage the shuttle lock or bend the pin.
- Ignoring a loose fit. If the socket feels sloppy by midday, add a sock ply rather than walking on an unstable leg. Pistoning wears out your skin and changes your gait in ways that stress your knee and hip.
- Using lotion before donning. Moisturize at night after you’ve removed the prosthesis for the day. Lotion or cream under the liner reduces friction in the wrong way, making the liner slip instead of grip.