LIMB DIFFERENCES – DEFINITIONS
A cooperative effort of the Amputee Coalition of America, Wayne Renardson, Ralph Fowler and Dick Mooney Revised by Julie L. Erwin, 2003
AAOP (American Academy of Orthotists and Prosthetists): A professional society of orthotists and prosthetists.
ABC Board Certified Practitioners: American Board of Certification in Prosthetics.
Abduction: Motion of a body part away from the mid-line of the body.
Abrasion: Wearing away of the skin through rubbing or friction.
ACA: Amputee Coalition of America. Founded 1986. Incorporated in 1989.
Accessible: Easy to approach, enter, operate, participate in, and/or use safely and with dignity by a person with a disability (i.e., site, facility, work environment, service, or program).
Acquired Amputation: Limbs surgically removed due to a disease or trauma generally diabetic/vascular, cancer, bone infection, non-union of fractures, or trauma.
Acupuncture: An original Chinese practice of puncturing the body at specific points to cure disease or relieve pain.
ADA: Americans with Disabilities Act. Enacted 1990.
Adherent Scar Tissue: Scar tissue formed in the healing process that sticks to underlying tissue such as muscle, fascia, or bone.
AE: Above elbow also referred to as “transhumeral.”
AK: Above knee also referred to as “transfemoral.”
Alignment: Position of prosthetic socket in relation to foot and knee.
Alternative Therapy: Treatment that is used in place of or in conjunction with traditional medicine. Examples include acupuncture, yoga, and tens units.
Amelia: Medical term for absence or partial absence of limbs at birth. Amelia can sometimes be caused by environmental or genetic factors.
Amputation: Loss or absence of all or part of a limb.
Anterior: Front, as front portion of a shoe or foot.
AOPA (American Orthotic and Prosthetic Association): A trade association of facilities (no individuals) that provide orthotic and prosthetic services.
Architectural Barrier: Stairs, ramps, curbs, or anything that obstructs your walking or wheelchair mobility.
Assistive/Adaptive Equipment: Devices that assist in activities or mobility, including ramps, bars, changes in furniture heights, environmental control units, and other devices.
Atrophy: A wasting of tissues; the decrease in the size of a normally developed extremity or organ.
BE: Below elbow also referred to as “transradial.”
Bilateral amputee: A person missing either both arms or both legs; a double amputee.
Biomechanics: Applying mechanical principles to the study of how the human body moves.
BK: Below knee also referred to as “transtibial.”
BOC: Board for Orthotists/Prosthetists Certification.
Body Image: The awareness and perception of one’s own body related to both appearance and function
Body-Powered Prosthetics: A prosthesis that usually employs a harness for two purposes: suspension and control. Through relative body motion, the amputee is able to generate tension in a control cable. By routing the cable, the tension can be transmitted to the prosthesis, where it can generate the desired effect.
Bumper: A rubber like (polymer based) device inserted into a knee or ankle component as a resistance or extension aid. Bumpers come in different durometers (color coded), which allow the amputee to have different resistance levels.
C-leg: The Otto Bock 3C100 C-Leg is a metal frame that holds a hydraulic cylinder, microchip, and rechargeable battery. The C-Leg system includes a strain pylon that senses weight and position providing information about the amputee’s gait to the microprocessor.
Causalgia: A constant, usually burning, pain resulting from injury to a peripheral nerve.
Check or Test Socket: A temporary socket, often transparent, made over the plaster model to aid in obtaining proper fit and function of the prosthesis.
Comorbidity: The presence of coexisting or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study.
Congenital Amputee: Individual born missing a limb(s). Technically, these individuals are not amputees but are “limb deficient:”
Congenital Anomaly (phocomelia): A birth abnormality such as a missing limb (amelia) or deformed limb.
Contracture: Tightening of muscles around a joint that restricts the range of motion.
Contralateral: Occurring on or acting in conjunction with a part on the opposite side of the body.
Cosmesis: Used to describe the outer, aesthetic covering of prosthesis. Refers to the appearance of the prosthesis, whether a “naturalistic” treatment is attempted.
CP (Certified Prosthetist): A person who has passed certification standards as set by the American Board of Certification in Prosthetics.
CPO (Certified Prosthetist-Orthotist): A person who has passed certification standards as set by the American Board of Certification in prosthetics and orthotics. Custom Fit: Fitting an individual with an item/device made from an image of the individuals anatomy fabricated according to the needs of that individual.
DAK: Double (aka bilateral) AK, also referred to as “bilateral transfemoral.”
Debride: A term for the removal of necrotic, infected, or foreign material from a wound.
Definitive, or “Permanent” Prosthesis: A replacement for a missing limb or part of a limb that meets accepted check-out standards for comfort, fit, alignment, function, appearance, and durability.
Desensitization: The process of making the residual limb less sensitive to touch by massaging, tapping, or using a vibrator.
Diabetic Amputation: Amputation due to complications caused by diabetes. Causes include neuropathy, ulcers, and foot disorders. An acquired amputation.
Disarticulation: An amputation through a joint; commonly the hip, shoulder, knee, ankle, elbow, or wrist.
Distal: (1) The end of the residual limb. (2) Farther from the central portion of the body. Opposite of proximal.
Donning and doffing: Putting on and taking off a prosthesis, respectively.
Dorsiflexion: Pointing the toe/foot upward, toward the body.
Durometer: Different “density” or strength and in the context means it will allow the ankle to move, bend, or
flex more or less.
Early Prosthetic Fitting: A procedure in which a preparatory prosthesis is provided for the amputee
immediately after removal of the sutures. (See IPOP)
ED: Elbow Disarticulation. An amputation through the elbow joint.
Edema: A local or generalized condition in which the body’s tissues contain an excess of fluid.
Elastic Wrap: Elasticized bandage used to prevent swelling and encourage shrinkage and maturation of the
residual limb.
Endoskeletal Prosthesis: A prosthesis built more like a human skeleton with support and components on
the inside. This design may have a soft cosmetic cover on the outside.
Energy storing foot: A prosthetic foot designed with a flexible heel. It is designed with a spring that stores
energy when weight is applied to it and releases energy when the amputee transfers weight to the other foot.
Ertl Procedure: A fibular stabilization procedure. The opposing bundles of cut muscle tissue are sewn to small holes drilled into the end of the bone of the residual limb. The major significance of this procedure is the increased surface area available for loading. Because the muscle has been directly attached to the bone, it remains active - thus maintaining its mass or even increasing in size.
Exoskeletal Prosthesis: A prosthesis that is hollow on the inside with a hard outer surface to bear weight.
Extension assist: A method of assisting the prosthetic to “kick forward” on the swing through phase to help
speed up the walking cycle.
Extremity or limb: Relating to arm or leg.
Foot Function: Substituting use of the feet for the hands.
Forequarter Amputation (lnterscapulthorasic): Amputation of the arm, shoulder, clavicle, and scapula.
Functional: Designed with the primary goal of controlling an individual’s anatomical function, such as
providing support or stability or assisting ambulation.
Gait Training: Learning how to walk with your prosthesis or prostheses.
HD: Hip Disarticulation. Amputation that removes the leg at the hip joint, leaving the pelvis intact.
HP: Hemipelvectomy. An amputation where approximately half of the pelvis is removed.
Hybrid prosthesis: A prosthesis that combines several prosthetic options in a single prosthesis, usually for
individuals who have a transhumeral (above the elbow) amputation or deficiency. The most common hybrid
prosthesis utilizes a body-powered elbow and a myoelectrically-controlled terminal device (hook or
hand).
IAOP: International Association of Orthotics and Prosthetics.
llizarov Technique: A bone fixation technique using an external fixator for lengthening limbs, correcting
pseudarthroses and other deformities, and assisting the healing of otherwise hopeless traumatic or
pathological fractures and infections, such as chronic osteomyelitis.
IPOP: “Immediate Post Operative Prosthesis.” A temporary prosthesis applied in the operating room
immediately after the amputation.
lschial Containment Socket: A derivative of the Narrow ML, as a special attempt is made to form a little
pocket for the isehium to sit in.
lschium: The lower portion of the hipbone. This is the bone that protrudes from your pelvis that may get sore
when sitting on a hard surface for extended periods of time.
Kinesiology: The study of human motion.
Knee Disarticulation (KD) or through the knee (TDK): Amputation of the leg through the knee.
Lateral: To the side, away from the mid-line of the body.
L-Codes: Reimbursement codes used in the prosthetic/health care industry to identify what services and/or
devices were provided.
LE: Lower extremity.
Liner: Suspension systems used to attach prosthesis to the residual limb and/or provide additional comfort
and protection of the residual limb. These liners may be made of silicon, pelite, or gel substances.
Long’s Line: A straight line from the head of the femur through the distal end of the femur down to the center
of the heel of the prosthetic foot.
Medial: Toward the mid-line of the body.
Modular Prosthesis: An artificial limb assembled from components or modules usually of the endoskeletal
type where the supporting member (pylon) and may have a cosmetic covering (See “Cosmesis”) shaped and
finished to resemble the natural limb.
Multiaxis foot: Allows inversion and eversion and rotation of foot and is effective for walking on uneven
surfaces.
Myodesis: Muscles anchored to end of bone. Referring to muscles anchored by sutures through the bone.
Myoelectrics: Literally muscle electronics. This is a technology used in upper-extremity prosthetics to control
the prosthesis via muscle contraction using electrical signals from the muscles to power the prosthesis.
Myoplasty: Muscles anchored to opposing muscles.
Neuroma: The end of a nerve left after amputation that continues to grow in a cauliflower shape. Neuromas
can be troublesome, especially when they are in places where they are subject to pressure from the
prosthesis socket.
Neuropathy: An abnormal and usually degenerative state of the nervous system or nerve.
Normal Shape/Normal Alignment (NSNA) Also know as a narrow ML socket. The socket more closely
approximates the shape of the musculature of a residual limb, when compared to a quad socket. The sides or
medial/lateral measurement is tightened down to squeeze the residual limb with most of the squeezing taking
place on the outside or lateral side. This helps control the rotation of the socket by putting pressure along the
fleshy area of the leg that can handle some side to side pressure.
Nylon sheath: A sock interface worn close to the skin on the residual limb to add comfort and wick away
perspiration.
Occupational Therapy/OT: Teaching how to perform activities of daily living such as feeding, grooming,
bathing, and dressing as independently as possible.
Orthosis: A device that is used to protect, support, or improve function of parts of the body that move.
Orthoses is plural.
Orthotics: The profession of providing devices to support and straighten the body.
Orthotist: A skilled professional who fabricates orthotic devices that are prescribed by a physician.
Osseointegrations: The growth action of bone tissue, as it assimilates surgically implanted devices or
prostheses to be used as either replacement parts or as anchors.
Partial Foot Amputation: An amputation on the front part of the foot. Also called “Choppart Amputation.”
Partial suction: Usually refers to the socket of an above the knee prosthesis that has been modified to allow
the wearing of prosthetic socks while wearing the prosthesis.
PFFD (Proximal femoral focal deficiency): A congenital anomaly where the proximal femur is lacking in
completeness.
Phantom pain: Pain that seems to originate in the portion of the limb that was removed.
Phantom sensation: The normal ghost image of the absent limb may feel normal at times and at other times
be uncomfortable or painful.
Phocomelia: Medical term for a congenital condition in which one or more limbs are missing, with the hand
and / or foot attached directly to the trunk of the body.
Physiatrist: A doctor of rehabilitation medicine who specializes in the comprehensive management of
patients with impairments and disabilities arising from neuromuscular, musculoskeletal, and vascular
disorders.
Physical Therapist: A therapist who is concerned with your gross motor activities such as transfers, gait
training, and how to function with or without a prosthesis.
Pistoning: Refers to the residual limb slipping up and down inside the prosthetic socket while walking.
Plantar: Bottom of the foot.
Plantarfiexed/Plantarfiexion: Means the toe is pointing down toward the sole. Almost like pushing the gas
pedal down and simulating that position or alignment.
Ply: Thickness of stump sock material. The higher the ply number the thicker the sock.
Pneumatic/Hydraulic: Used in reference to knee joints and provides controlled changes in the speed of
walking.
Posterior: The back side of the body or part in question, i.e. posterior knee or patellar region.
Prehension: To hold, grasp, or pinch.
Preparatory Prosthesis: An unfinished functional replacement for an amputated limb, fitted and aligned in
accordance with sound biomechanical principles and worn for a limited period of time to accelerate the
rehabilitation process.
Prosthesis: An artificial part of the body. In the case of amputees, usually an arm or a leg. Prostheses is
plural.
Prosthetics: The profession of providing cosmetic and/or functional restoration of missing human parts.
Prosthesist: A person involved in the science and art of prosthetics. One who designs and fits artificial limbs.
Proximal: Nearer to the central portion of the body. Opposite of distal.
PTB: Patellar Tendon Bearing. BK prosthesis where weight is on the tendon below the kneecap.
Pylon: A rigid member, usually tubular, between the socket or knee unit and the foot that provides a weight
bearing support shaft for an endoskeletal prosthesis.
Quad Socket: A socket designed for an above the knee amputee that has four distinctive sides allowing the
muscles to function as much as possible.
Ramus: The front middle portion of the pubic bone palpated just above the genitals.
Range of motion: The amount of movement a limb has in a specific direction at a specific joint such as your
hip or knee.
Reattachment surgery: The surgical attachment of a severed limb that involves reconnecting the arteries
and grafting skin and muscle together. Some also involve putting the patient in a hyperbolic chamber, which
causes the blood vessels, skin, muscle, and nerve tissues to regenerate more quickly and completely.
Rehabilitation: The process of restoring a person who has been debilitated by a disease or injury to a
functional life.
Residual limb: The portion of the arm or leg remaining after the amputation. Some people refer to it as a
“stump.”
Revision: Surgical modification of the residual limb.
Rigid Dressing: A plaster wrap over the residual limb, usually applied in the operating or recovery room
immediately following surgery for the purpose of controlling edema (swelling) and pain. It is preferable, but not
necessary, that the rigid dressing be shaped in accordance with the basic biomechanical principles of socket design.
SACH Foot: Solid-Ankle Cushion Heel.
Shock Pylon: A prosthetic pylon that dampens the vertical forces exerted on the residual limb and is used to
cushion the impact when walking.
Shoulder Disarticulation (SD): Amputation through the shoulder joint.
Shrinker: A prosthetic reducer made of elastic material and designed to help control swelling of the residual
limb (edema) and/or shrink it in preparation for a prosthetic fitting.
Shuttle lock: A mechanism that locks a pin attached to the distal end of a liner locking the residual limb into a
socket.
Single Axis Foot: A foot is based on an ankle hinge that provides dorsiflexion and plantarflexion, i.e. toe up
and toe down.
Socket: The portion of the prosthesis that fits around the residual limb/stump and to which the prosthetic
components are attached.
Social Worker: A professional who assists you by helping to coordinate your discharge from the hospital and
oversees appropriate contact with other services or organizations. The social worker will help to facilitate your
re-entry into family and community life.
Soft socket: A soft-liner built into a prosthetic socket to provide cushioning or permit muscle function.
Split hooks: Terminal devices with two hook-shaped fingers operated through the action of harness and
cable systems.
Stance control: Friction device with an adjustable brake mechanism to add stability to a prosthetic knee unit.
Stump: A word commonly used to refer to the residual limb.
Stump Shrinker: An elastic wrap or compression sock worn on a residual limb to reduce swelling arid shape
the limb.
Suction socket: A socket designed to provide suspension by means of negative pressure vacuum in a
socket. Achieved by forcing air out of the socket through a one-way valve when donning and using the
prosthesis.
Supercondular Suspension: A method of holding on prosthesis by clamping on the bony prominence above
a joint, called “Condyles.”
Suspension system(s): The method used to hold the prosthesis on to the body. Includes locking pin, TES
belt, suspension sleeve, waist belt, supercondular, PTB, and suction.
Swing phase: Prosthesis moving from full flexion to full extension. Usually used in reference to prosthetic
knee units.
Switch control: Use of electric switches to control current from a battery to operate an electric elbow, wrist
rotator, or terminal device.
Symes amputation: An amputation through the ankle joint that retains the fatty heel pad portion and is
intended to provide end weight bearing.
TEC: Total Environmental Control liner.
Temporary Prosthesis: A prosthesis made soon after an amputation as an inexpensive way to help retrain a
person to walk and balance while shrinking the residual limb.
TENS Unit: Transcutaneous Electrical Nerve Stimulation. The units are small, battery powered, and weigh
only a few ounces. Electrodes are placed on the skin near the area of pain and are attached to the TENS unit
and electrical currents, which disrupts the pain signal so that the pain is no longer felt, are sent to the effected
nerves
Terminal devices: Devices attached to the wrist unit of an upper extremity prosthesis that provides some
aspect of the function (grasp, release, cosmesis, etc.).
TES belt: A neoprene or Lycra suspension system for AK prostheses that has a ring that the prosthesis
slides into. There is a neoprene belt that attaches around your waist by Velcro/hook and loop fastener. Used
to give added suspension of a prosthesis and/or control rotation.
Therapeutic custom shoe: A shoe designed and fabricated to address an individual’s medical condition. A
therapeutic custom shoe is made over a modified positive model of an individual’s foot and can be either
custom-molded or custom-made.
Therapeutic Recreation: Provides instruction in returning to leisure activities.
Transfers: Moving from one position to another (such as from sitting on a bed to sitting in a wheelchair).
Transtarsal amputation: Through the tarsal (tarsus) or foot bones. See partial foot amputation.
Traumatic amputation: An amputation that is the result of an injury.
Unilateral: Affecting only one side.
Upper extremity (UE): Having to do with the upper part of the body. In reference to amputees with arm or
shoulder amputations.
Van Ness Rotation Plasty: In this kind of reconstruction, the ankle is used as a substitute for a knee. By
removing a portion of the femur and knee joint and bringing the ankle up to the level of the original knee,
turning it 180 degrees, reattaching it to the femur and adjusting the thigh to appropriate length, a functional
knee joint (formerly the ankle joint) can be achieved. The foot is then fit into a prosthetic socket and a person,
who would otherwise require an above-knee amputee, functions as a below-knee amputee.
Variable Volume Socket: Lightweight and custom-made. The two-piece design makes it possible to don and doff the prosthesis without subjecting the dysvascular limb to unnecessary shear. The patient can adjust the socket itself as well as vary the sock ply to maintain proper fit. Socket adjustability eliminates the need to replace the preparatory socket several times before stabilization occurs.
Vascular Amputation: Amputation caused by lack of blood flow to a limb or limbs. Causes include arterial and venous catheterization, heart defects and disease, thrombocytopenia, familial coagulation defects, arterial anomalies, pressure, septic emboli and mucocutaneous lymph node syndrome. An acquired amputation.
Voluntary-closing devices: Terminal devices that are closed by forces on a control cable; grasp is proportional to the amount of pull on the cable.
Voluntary-opening devices: Terminal devices that are opened by body motion and closed by elastic bands or springs.
Wrist Disarticulation (WD): Amputation through the wrist.
Yoga: An eastern philosophy teaching the suppression of all activity of body, mind, and will. The practice works on the body to reduce or eliminate pain by helping the brain’s pain center regulate the controlling mechanism located in the spinal cord. It also assists the brain with secretion of natural painkillers through the body.