Hinged Knee Braces: Who Needs One and How They Are Fitted

How a hinged knee brace works

A hinged brace has:

• Side bars (uprights) of metal, carbon or hard plastic on the inner and outer sides of the knee, which keep the joint from bending sideways.
• Hinges at the knee line. Simple hinges allow free bending. Adjustable hinges can be set to limit how far the knee can straighten or bend, with stops.
• Cuffs or shells above and below the knee, on the thigh and calf, to anchor the brace.
• Straps with Velcro or buckles, which hold the cuffs to the leg.
• Padding to protect skin and bone.

The brace gives support in three ways: it spreads the force across the thigh and calf, limits movement in certain directions and helps the person feel the joint position. It does not take over the muscles' job entirely, and it cannot make a badly damaged joint normal. Some braces are off-the-shelf in standard sizes; others are custom-made from measurements or casts for an exact fit, usually by an orthotist.

Who may need one

A doctor or physiotherapist may advise a hinged brace in situations such as:

• Ligament injury, such as a sprain or tear of the collateral or cruciate ligaments, where the knee is unstable.
• After certain knee surgeries, such as ligament reconstruction, fracture repair or some procedures where movement must be limited for a period. After knee replacement, braces are used only if the surgeon advises; see knee replacement recovery equipment.
• Fractures around the knee, during healing; see supports and braces after a fracture.
• Instability or "giving way" from a damaged joint, when surgery is not possible.
• Severe osteoarthritis with misalignment, where an unloader brace is chosen by a specialist.
• Neurological conditions, where the knee buckles, such as after stroke, with advice.

For ordinary aches in an older knee, a soft sleeve or no brace is usually enough; see knee support buying guide.

Who should not use a brace without advice

• People with poor circulation, swelling or varicose veins, where straps can block blood flow; see swollen legs in older adults.
• People with numb legs, who may not feel pressure, such as in diabetes; see neuropathy foot care.
• People with fragile or broken skin, ulcers, or skin conditions.
• A person with a hot, red, swollen knee, which needs a medical diagnosis.
• Anyone with an unexplained injury or fall, until a fracture is excluded.
• People who cannot put the brace on or take it off themselves and do not have help.

How a brace should be fitted

Fit is everything. A properly fitted brace sits snug without moving; a poorly fitted one slides, pinches or leaves gaps.

1. Professional assessment. A physiotherapist, orthopaedic doctor or orthotist examines the knee, decides on the type of brace, and takes measurements. For off-the-shelf, they measure the thigh and calf circumference at set points above and below the knee, the leg length and sometimes the knee width. 2. Choosing size and model. Based on charts, allow for swelling that may change. If the knee is swollen, a brace may need to be adjustable. 3. Aligning the hinge. The hinge centre should lie alongside the knee joint centre, roughly level with the top of the kneecap or slightly above the joint line, on both sides. Misplaced hinges move up or down the leg as the knee bends, causing rubbing and loss of support. The therapist checks this with the person standing and sitting. 4. Setting the stops. If the brace limits straightening or bending, the doctor sets the angles and locks them. Do not change them without advice. 5. Strapping. Straps are tightened from the bottom up or in an order the maker specifies, to a snug fit that does not cut off blood flow. You should be able to slide a finger under the strap. 6. Test. Walk, sit, stand and climb a step to check it stays in place and is comfortable. Check the foot for colour and warmth. 7. Wearing instructions. Ask how long to wear it each day, and whether at night, in the shower or during exercise. 8. Follow-up. Brace fit can change as swelling goes down, muscles change or weight shifts. Review.

Putting on and taking off

Practice with a helper present.

• Sit with the knee slightly bent and the brace laid open beside you.
• Smooth the skin, and wear a thin cotton sock or a stockinette sleeve under the brace if advised, to reduce rubbing and sweat.
• Position the hinges at the correct level, close the cuffs and fasten the straps in the right order.
• Check that it does not twist.
• Stand and check alignment.
• To remove, release the straps in order, open the cuffs and slide it off.

People with stiff hands may need a wrap-style brace or help from a carer. An occupational therapist can suggest strap aids or dressing aids; see dressing aid guide.

Wearing times and exercise

Do not guess. Doctors give specific advice, which may include:

• wearing it whenever the person is up and walking, and removing it for rest in bed;
• wearing it only for certain activities, such as walking outdoors;
• keeping it on at night after certain operations;
• removing it for hygiene and skin checks.

Braces should not replace muscle strength. A physiotherapist will teach exercises for the thigh and calf, which keep muscles working and protect the joint when the brace is off; see gentle exercises for knee and hip pain and rehabilitation after fracture or surgery: physio plan.

Skin and circulation checks

Every day, take the brace off and look at the skin, especially behind the knee, over the bone edges and under the straps.

• Look for red marks that do not fade within half an hour, blisters, rubbing, itching or rash.
• Feel for heat, swelling or tenderness.
• Check the foot for colour changes, coldness, numbness or tingling. If the foot goes pale, blue or numb, loosen the brace and seek advice.
• Check for swelling below the brace, which can mean straps are too tight or fluid is building up.
• Keep skin clean and dry, particularly in humid weather, to avoid fungal rashes; see skin conditions in older adults.
• Do not apply creams under the brace unless advised.

If the skin is damaged, stop wearing the brace and contact your doctor or physiotherapist.

Using with walking aids and at home

A brace does not make a knee safe on its own. Many people wearing a brace also need a stick, a frame or crutches for a period; see walking frame after hip or knee surgery and how to choose a walking stick. At home, keep floors clear, add a night light and use sturdy footwear; see falls risk assessment at home. Bathing may need a shower seat; see shower chair buying guide.

Care and maintenance

• Wipe the frame and pads with a damp cloth and mild soap; check whether pads are removable and washable.
• Dry thoroughly.
• Check hinges for loose screws and wear; do not oil without advice.
• Check straps and Velcro for wear, and replace worn parts.
• Do not leave the brace in a hot car or direct sun.
• Replace a brace that is bent, cracked or no longer fits.

Common mistakes

• Buying a hinged brace without an assessment.
• Choosing the wrong size, leaving gaps or pinching.
• Misaligning the hinge.
• Tightening straps too much.
• Wearing it too long and neglecting exercises.
• Using it to "go back to full activity" without clearance.
• Ignoring skin changes.
• Handing a brace to another person.

When to ask a professional

See a physiotherapist, orthopaedic doctor or orthotist before buying a hinged brace, and return if the brace causes pain, slips, rubs or does not seem to help. Ask your doctor urgently for a calf that is swollen, red, warm and painful, a foot that is cold, pale or numb, sudden increase in knee pain or swelling, fever, or a fall with new inability to bear weight. A pharmacist can advise on mild skin irritation.