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35 of the most common orthotics terms you should learn

4th May 2017

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Orthotics can include splints, collars, insoles, support braces, dressings and many other products that help people with rehabilitation after a sports injury, or with ongoing movement problems. It’s a wide area, so this guide aims to untangle some of the specialist terms you may come across.

3-D printing: The most exciting development in the production of custom orthotic aids, 3D printing may well revolutionise the way an orthosis is used in the future, as it will allow one-off aids to be produced.


ACL: Anterior Cruciate Ligament which runs diagonally across the knee. Its job is to stop the kneecap from sliding forward.

Damage to the ACL is graded by severity from 1 to 3

Adduction / abduction: Used when a physiotherapist or medical professional is moving the limb toward the midpoint line of the body (adduction) or away from the midpoint line of the body (abduction).

Anterior: Used throughout orthotics and physiology to describe the front of joints or limbs.

Antero-lateral: The outer and front sides of a joint or limb.

Antero-medial: The inner and front sides of a joint or limb.

Articulation: Describes the movement of a joint, and by extension, the functional components in an orthotic device, which control joint movement.

Bespoke: Braces or aids that are designed specifically for you, based on measurements and photographs, and an assessment of your support requirements and activities.

CAM Foot brace: A type of brace that provides Controlled Ankle Movement. These braces allow patients to walk even when they have very intense injuries.

Carbon Fibre: This is a preferred material for orthotic aids such as knee braces. It is very light, but strong, so can protect the knee ligaments in high-impact activities such as certain sports. Very high impact sports require knee braces with extra carbon fibre layers. Pre-preg carbon fibre is impregnated with resin, then heated. This results in a material that has the optimum weight/strength ratio.

The CTi is worn by extreme sports professionals such as Aaron Hadlow

Cervical Collars: This is another name for a neck brace, used when injury has occurred. It is usually a full collar, all the way round the neck. A lighter orthotic called a neck support is used in some sports to support the neck and prevent injury.

Cockup Wrist Splint: Tempting as it is to imagine this is what you need when you mess up during a sports event and get injured, it’s actually a type of orthotic which will immobilise your wrist, keeping it stable so that it gets a chance to heal.

A wrist support may be worn following a wrist injury

Condyle Pad: Used on the inside hinge of knee braces, to help the brace fit correctly to your knee. They are replaceable if they become worn or torn, and they come in various thicknesses.

Custom: When applied to braces or orthotic aids, this means that your personal measurements and specific requirements are used to manufacture a unique aid that fits you exactly.

Diabetic Insole or Pressure Relief Ankle Foot Orthotic: This provides support right across the foot, so that the person’s weight is evenly spread across the foot. This can reduce the pressure on areas that might otherwise be prone to developing ulcers.

Foot orthotics: Often simply known as “insoles”, these can be divided into two types. Firstly, there are functional orthotics that are either custom-made or bought over the counter, and which aim to correct mechanical foot problems. Secondly, there are accommodative orthotics, which support the foot but don’t try to make the joints align differently.

Halo Brace: An orthotic aid for the neck, when people have fractures that are unstable, and pins have been used to stabilise the head.

“Hard” Orthotic: This is a foot orthotic, or insole, which has been designed to carry out a specific function, such as preventing the foot moving abnormally during walking or sports. Hard orthotics are made of fairly rigid materials, although their rigidity is a product of how thick they are and what they are made of. The size of the patient’s feet and their weight, as well as their need for support, can also influence how rigid the orthotic insole needs to be.

Lateral: Used to describe the side of a joint or limb

Non-corrosive: When orthotic aids are being used in water sports, they should be built of materials that won’t corrode, even when exposed to salt water. They must be rinsed however, after contact with dirt, salt and debris.

LCL: Lateral Collateral Ligament. This is the ligament that joins the outside of the thigh bone to the lower leg bone.

Damage to the LCL is graded by severity from 1 to 3

MCL: Medial Collateral Ligament. This is found on the inside of the knee joint, and links the shin bone to the thigh bone.

Damage to the MCL is graded by severity from 1 to 3

Orthopaedic Surgeon: A specialist consultant who assesses and treats bone and joint problems. The surgeon can operate to correct problems, treat fractures or to improve your gait and general movement.

Orthotist: Medical professional who specialises in designing and fitting orthotic aids and assistive devices. Many work in the NHS, others work privately, carrying out fitting for clients who have ordered items such as knee braces. Whether custom-made or off the shelf, these have to be fitted correctly by an expert fitter.

OTS: Stands for “Off the shelf”. When you buy a brace or aid that hasn’t been specifically made for you, but is part of a product range from a manufacturer, it is “off the shelf”.

Patella Cup: Fits over the kneecap and cushions it from impact in sport. A patella cup is often used with a knee brace to provide full protection, especially in motor sports.

PCL: Posterior Cruciate Ligament. One of the four major ligaments of the knee, found at the back of the knee. It can become unstable after injury, and knee braces are usually recommended for anyone with PCL instability, who is thinking of engaging in sports activities.

Physiotherapist: A medical professional who works with patients suffering from musculo-skeletal problems, prescribes exercises and aids, and manipulates joints and limbs to improve function.

Physiotherapy is one of the treatment pathways available post injury

ROM Walker: Like the CAM foot brace, this is a “Range of Motion” brace that will allow walking, even with a severe injury.

Silicone liner: A soft, durable liner that is used with a brace, to allow the skin to breathe, and to prevent the brace causing abrasion of the skin.

“Soft” Orthotic: This has the same function as the hard orthotic insole. It is used either to support the foot, often with pads under the arches, or to stop the foot moving wrongly when the person is walking. However, these orthotics are made from flexible materials. They tend to be thinner, and their suitability will depend on the weight of the patient, their foot size, and how much their foot movement needs to be supported or controlled.

Subshell: A flexible moulded part of a knee brace which hugs the contours of the leg.

Thumb Spica: May be part of a cockup wrist splint (see above), and is also used when a thumb is broken, to immobilise it. Skier’s thumb (also known as gamekeeper’s thumb) is one of the conditions it treats.

Tibial strap: The tibial band runs down the thigh. Runners can get Iliotibial Band Friction Syndrome (ITBFS), commonly known as “Runner’s Knee”. A Tibial Strap is used in combination with a knee brace, or on its own, to compress the area above and below the tibia (kneecap). This reduces the tension in the tibial band, and relieves pain.

Vaulting: An unwanted movement when you are walking with an orthotic aid. You try to avoid walking on the whole foot, and instead walk on your toes. It’s an indication that the insole needs adjustment.

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