Glossary of Terms

A
A/P	Anterior/Posterior (anatomic terms)
AAOS	AmericanAcademy of Orthopedic Surgeons
Abdomen	A portion of the body between thorax and pelvis.
Abduct	To draw away from the midline.
Abduction	The act of drawing away from the midline; opposite of adduction.
Abductor	A muscle performing the function of abduction.
Abscess	Localized collection of pus.
Acetabulum	The cavity in the os coxae (hip) into which the head of the femur fits.
Acromium	Bony process of the scapula which forms the point of the shoulder.
Acute	Severe and/or short duration; used in speaking of duration and severity of disease.
Adamant	Extremely hard, as enamel of tooth.
Adduct	To draw toward the midline.
Adduction	The act of drawing toward the midline; opposite abduction.
AHS	Apollo Hip System
AKS	Apollo Knee System
Allograft	A tissue transplanted to a different individual of the same species.
Alloy	A mix of metals designed to improve implant material properties for specific purposes.
All-poly	A component composed entirely of polyethylene, with no metal parts.
Amphiarthrosis	A joint with little movement and no joint cavity.
Anconeus	Pertaining to the elbow.
Ankylosis	The fusion of a joint.
Anteflexion	A forward curvature; a condition in which the upper part of an organ is bent forward; opposite of retroflexion.
Anterior	Placed in the front or forward part; opposite of posterior.
Anteversion	A forward turning; a condition in which an entire organ is abnormally tipped forward.
Apex	Top or summit.
Aponeurosis	A flat sheet of white fibrous tissue, usually serving as an attachment for a muscle; plural aponeuroses; aponeurotica, Latin adjective.
Appliance	Device used in Support or fracture fixation external or internal.
Apposition (see also mineral apposition)	The state of being fitted together, being in contact at the ends.
APR	Anatomic Porous Replacement (Hip System).
Aqueous	Watery
Arthritis	Inflammation of a joint.
Arthrodesis	Fusion of a joint, eliminating all motion.
Arthroplasty	The surgical reconstruction of a joint.
Arthrosis	A joint: from the Greek.
Arthrotomy	Cutting into a joint.
Articular	Pertaining to a joint. Surfaces that "fit together."
Articulation	Movement of a joint; from the Latin.
Asepsis	A condition free from germs; free from infection.
Aspect	Position, surface, or face.
Aspirate	To remove by suction.
Asymmetric design	A design which mirrors the natural, anatomic contours of a joint, a design which comes in right and left configurations.
Atrophy	A wasting away of tissue usually through disuse.
Autograft	A tissue transplanted from one part to another part of the same body.
Autonomic	Being self-controlled; independent.
Axial	Pertaining to the axis or line about which a body turns, therefore pertaining to the trunk; opposite of appendicular.
B
Beads, beaded, beading	Term used to describe implant coatings made of tiny spheres.
Biaxial	Turning about two axes (having two axes).
Biconcave	Having two concave surfaces.
Bilateral	Occurring on both sides of a midline point or pertaining to both sides of the body (ex. bilateral knee replacement means having both knees replaced).
Biocompatibility	Materials that can coexist with living tissue without being harmful or toxic or being rejected by the host. The most common materials for joint replacement are polyethylenes, metals and ceramics, each has specific biocompatible characteristics.
Biomechanics	The study of the relationship between forces and motion in biologic systems,, like the human body.
Bipolar	Having two poles or processes.
Blood	A fluid tissue circulating through heart, arteries, veins, and capillaries.
Bone cement (see also cement)	Material usually made of polymethylmethacrylate (PMMA) which acts like a grout between an implant and the patient’s bone.
Bone growth factor	Material usually made of polymethylmethacrylate (PMMA) which acts like a grout between an implant and the patient’s bone.
Brachial	Pertaining to the arm.
Broach, broaching	A broach is a tool or instrument used to enlarge the interior canal of bones to allow for insertion of implants, broaching is the process of enlarging the canal.
C
Cage	A type of spinal implant.
Calcaneus	The heel bone; also termed calcaneum.
Calcar	A thickened plate of bone near the head of the femur.
Cancellous	The lattise-like bone structure; softer bone.
Cancellous bone	A type of bone characterized by a spongy or lattice-like structure. Also known as Trabecular Bone.
Cancellous-structured titanium (see also CSTi)	A specially-manufactured, patented type of titanium coating that permits bone ingrowth because of its lattice-like surface texture.
Capitate	Bone of the wrist having head-shaped process.
Capitulum	Little head.
Capsular	A ligament which surrounds a movable joint.
Caput	Head; capitis, "of the head."
Carpal	Pertaining to the wrist.
Carpus	The wrist; carpi, "of the wrist."
Caudal	Pertaining to any tail-like structure; inferior in position.
Cement (Bone cement)	Material usually made of polymethylmethacrylate (PMMA) which acts like a grout between an implant and the patient’s bone.
Cemented	An implant which is secured in a patient’s body with the aid of bone cement or the process of using cement to help fix an implant.
Central	Situated in the midportion as opposed to peripheral.
Chronic	Of long duration; opposite of acute.
Circumduct	To rotate in a cone shape around a single point, as in the shoulder joint.
Circumflex	Bent or turned about.
Clavicle	The collar bone.
Clinical pathway	Established methodologies and decision trees for use by health professionals and patients in planning and preparing for medical intervention.
Coatings (see also porous, beads)	Any number of different materials applied to the surface of an implant or prosthesis to aid in fixation; porous coatings generally permit ingrowth into the implant.
Cobalt-chrome (CoCr)	A metal alloy with excellent resistance to fatigue, cracking and stress, widely-used in orthopedic implants.
Coccyx	Last, lowest portion of vertebral column (tailbone).
CoCr	Cobalt Chrome Alloy, a metal alloy with excellent resistance to fatigue, cracking and stress, widely-used in orthopedic implants.
Collar, collared	The top edge of a hip stem implant which rests on the top edges of the bone in which it was implanted.
Component	A part of an implant system, for example the patellar component is that piece that either replaces or enhances the original patella (knee cap).
Concave	Having a depressed surface; center is at a lower level than edge; opposite of convex.
Condyle	A rounded knob on the end of a hone; a knuckle.
Condyloid	Resembling a knuckle.
Congenital	Present at birth, as in CDH, congenital dislocated hip.
Congruent, congruence	The degree of constraint of two articular implants.
Convex	Having a rounded elevated surface; opposite of concave.
Coracoid	Like a crow's beak; variant or coronoid.
Costal	Pertaining to a rib or ribs.
Coxa	The hip; coxae, "of the hip."
Cranial	Pertaining to the cranium.
Cranium	The skull or brain pan.
Cruciate	Shaped like a cross.
Cruciate ligament	Any paired set of ligaments that cross over each other in an "X" formation, usually used to refer to the posterior cruciate ligament and the anterior cruciate ligament of the knee, which help stabilize the forward and backward motion of the knee.
Cruciate-retaining	A knee system design that allows the surgeon to keep the patient’s cruciate ligament.
Cruciate-sacrificing (see also PS)	A knee system in which the design of the implant must serve to stabilize the forward and back motion of the knee components because of an excised or deficient patient’s ligament.
CSTi	A specially-manufactured, patented type of titanium coating that permits ingrowth because of its lattice-like surface texture.
Cubital	Pertaining to the tile space in front of the elbow joint.
Custom	An implant manufactured to the demands of a surgeon based on the specific needs of one patient.
Cyclic fatigue	A biomechanical measure of stress placed on a material, measured in "cycles" of regular motion (as in joint motion - rotation, bending, etc.).
D
Deltoid	Triangular; resembling the Greek letter, delta.
Design rationale	The justification for an implant design based on extensive research into materials, clinical data, function, style, anatomical constraints, etc.
Diagnosis	Recognition of disease from symptoms.
Diathrosis	A freely moveable joint; plural diarthroses.
Digiti	Of a digit.
Digitorum	Of the digits.
Dislocation	The displacement of any part, especially the removal temporarily of a bone from its normal position in a joint.
Distal	Remote; opposite of proximal.
Dorsiflex	To turn toward the back; opposite of palmar flex.
E
Endosteum	Tissue surrounding the medullary cavity of bone.
Epi	A prefix meaning "on" or "above" opposite of hypo.
Epicondyle	A prominence or a bone on or upon a condyle.
Epiphysis	A part of process of a bone which ossifles separately before making osseous union with the main portion of the bone; the "growth plate" of bones.
Etiology	The study of the causes of disease.
Eversion	The act of turning outward; opposite of inversion.
Evert	To turn out; to turn tile sole of the foot outward opposite of invert.
Extension	A movement at a joint bringing the two parts into or toward a straight line from a flexed position; opposite of flexion.
External	On the surface or outer side; opposite of internal. Latin adjective, externus or externa.
Extra	Prefix meaning "outside of," opposite of intra.
F
FDA	Food and Drug Administration
Femur	Thigh; bone of the thigh; femoral is the adjective; femoris, "of the thigh." Smaller bone of lower leg; tile splint bone.
Fixation	The act, process or operation of holding, suturing or fastening something into a fixed position. In orthopedics, often refers to the stability and immobilization of an implant into the patient’s body.
Flexion	Sagittal plane movement in which the anterior surfaces of two segments are brought closer to each other; opposite of extension; bending of a joint.
Flexure	The curved or bent part of a structure.
Foramen	A hole; plural, foramina, or foramens.
Fossa	A pit or hollow; plural, fossae.
Fracture	A break in the continuity of bone.
G
Glenoid	Resembling a pit or pocket. The glenoid fossa of the scapula is very shallow. Analogous to the acetabulum of the hip.
GMP	Good Manufacturing Practices, part of total quality systems.
H
Hallux	The great toe; hallucis "of the great toe."
Harris Hip Scores	A numerical rating scale used for evaluation of the hip. The Harris Hip Rating Scale evaluates pain, function, absence of deformity and range of motion. One hundred is the highest possible total.
HSS Knee Scores	Hospital for Special Surgery Knee Scores, a numerical scale for rating knees.
HTO®	High Tibial Osteotomy, a technique for the treatment of unicompartmental gonarthrosis (knee arthritis).
Humerus	The upper arm bone.
Hydroxyapatite (HA)	A bioactive calcium phosphate ceramic similar to normal bone, may be applied to implant surfaces.
Hyper	Prefix meaning above; opposite of hype.
Hyperplasia	Increase in size of a tissue or organ due to an increase in the number of cells.
Hypertrophy	Increase in the size of a tissue or organ due to an increase in the size of its constituent cells.
Hypo	A prefix meaning below or under; opposite or epi or hyper.
I
IDE	Investigational Device Exemption (studies of experimental products).
Ilium	The bone of the flank; adjective is iliac; ilio is the combining form.
Implant (see also stem, prosthesis)	A device (or tissue or substance) that is transferred, grafted, or inserted into a living body.
Index	Referring to the forefinger or "pointing" finger.
Inferior	Situated or placed below; opposite of superior; inferioris, a Latin form of the adjective.
Infra	A prefix meaning "beneath," opposite of supra.
Ingrowth, bone or bony ingrowth	The process of living bone or tissue growing up to and into the surface of an implant, very important for stabilization and long-term life of the implant.
Instrument	A tool or implement used in surgery.
Inter	A prefix meaning "between".
Interbody fusion	A surgical technique for achieving bony fusion between invertebral bodies, term used to describe a specific back surgery technique.
Interface	Surface forming a common boundary between two bodies (used to describe the interaction of implant and living tissue).
Internal	Within or on the inside.
Intra	A prefix meaning "within".
Inversion	The act of tuning inward; opposite of eversion.
Invert	To turn in; to turn the sole of the foot inward; opposite of evert.
Involuntary	Performed against the will or consent.
Ischium	Bone of the hip; adjective is ischiatic, ischial, or sciatic.
ISO	International Standards Organization, a standards issuing body.
K
Knee Society Scores	A numerical scale for evaluating knee function developed by the Knee Society.
Kyphosis	An abnormal condition (curvature) of the spine; hunch-backed.
L
Lateral	Pertaining to the side; opposite of medial.
LD	Low-demand or low density
LDPE	Low Density Polyethylene
Ligament	Fibrous connective tissue connecting the articular ends of bones serving to bind them together and to facilitate or Ijinit motion.
Lordosis	Abnormal anterior convexity of the lumbar spine.
Lumen	Space within a tube or organ.
Lunate	A bone of the carpus shaped like a crescent moon.
Luxation	Dislocation of a joint.
M
M/L	Medial/Lateral (anatomic term)
Major	Larger, opposite of minor, majus is neuter adjective.
Malleolus	A little hammer (mallet); a hammer-shaped process; ankle bone. Plural, malleoli.
Mandible	Bone of lower jaw.
Marrow	Soft central part of a bone.
Maxilla	A jawbone; particularly the bone of the upper jaw.
Media	Middle
Medial	Pertaining to the center; opposite of lateral.
Median	Pertaining to the middle; that is, between two other structures.
Meniscectomy	Removal of the meniscus cartilage of the knee.
Meniscus	A "C" shaped cartilage in the knee which provides a stabilization system for the knee and a measure of shock absorption.
Metacarpus	Beyond the instep; the five bones of the foot between the toes and tarsal bones.
Metal-backed	Term used to describe implants that have a polyethylene liner set in a metal shell or on a metal base, the metal portion would rest in a prepared area in the bone and the polyethylene side would move against other metal components.
Minor	Smaller, opposite of major.
Morphology	The study of the structure of organisms, used colloquially to refer to the structure of body parts.
N
Navicular	Boat shaped; carpal bone at the base of the thumb. Also called the scaffoid.
Necrosis	Death of areas of tissue or bone surrounded by healthy tissue.
NK	Natural-Knee®, a trade-marked name for a anatomically-designed knee prosthesis.
Non-porous	An implant designed to be used with bone cement for stabilization; a surface that is not designed for nor coated with surfaces for ingrowth.
O
O.R.I.F.	Open Reduction, Internal Fixation.
Oblique	Slanting; between horizontal and vertical directiov..; Latin adjective, obliquus.
Olecranon	From the Greek word for elbow. The pominence at the proximal end of the ulna.
Opposition	The act of opposing one part to another.
Orbital	Pertaining to the orbit (eye).
Organ	A group of tissues having a special function.
Orthopedics	Branch of medical science that deals with treatment of disorders involving locomotor structures of the body, especially the skeleton, joints, muscle, fascia.
Orthopedist	A physician specializing in orthopedics.
Os	Bone; Os coxae - hip bone.
Osmosis	Passage of fluid across a membrane from a lesser to a more highly concentrated solution.
Ossification	Formation of bone.
Osteophyte	An abnormal bony outgrowth
Osteoporosis	Increased porosity of bone.
Osteotomy	Cutting and repositioning bone to more functional position.
Outcomes	The results of surgery in terms of patient satisfaction, reduction of pain, improved function, etc. Outcomes are tracked by hospitals and practices.
Outcomes management	The process of collecting, tracking and interpreting outcomes data.
Oxygenless	A patented procedure used by Zimmer in the packaging of polyethylenes where oxygen is removed from the packaging. Lab testing has shown the process decreases the wear rates of PE (polyethylene).
P
Palmar	The palm of the hand.
Para	Prefix meaning "beside," "accessory to" or near.
Patella	The kneecap
Patient Satisfaction Surveys	Surveys which seek to measure patients’ satisfaction with their surgery, recovery, etc. These form part of the outcomes data that surgeons and hospitals track.
Pearls (see surgical pearls)	Expert surgical techniques developed by senior surgeons, often for particular implants or procedures.
Pedal	Pertaining to the foot.
Pelvis	A basin or basin-like structure.
Peri	Prefix meaning "around."
Peripheral	Located on or near the surface of a part.
Pes	The foot; pedis, "of the foot."
Phalanges	Plural of phalanx, which refers to any bone of the finger or toe.
Plantar	Pertaining to the sole of the foot; plaritaris; Latin adjective plantae, "of the sole of the foot."
Plasma	Fluid portion of the blood.
Plasma spray	A coating for implants
Plastics (see also polyethylene, UHMWPE)	A common term that in orthopedic devices refers usually to polyethylene and more specifically to ultra-high molecular weight polyethylene (UHMWPE).
PMA	Pre-Market Approval (FDA approval after IDE study is complete).
PMMA (see also cement, bone cement)	Poly methylmethacrylate (bone cement).
Polyethylene	A type of plastic formed by the polymerization of ethylene. Different structural properties come from differences in molecular weight, branching, cross-linkage and crystallinity. The most common form used in orthopedic devices is ultra-high molecular weight polyethylene (UHMWPE).
Pore	Small holes or spaces on the surface or interior of a material.
Porous	Characterized by pores and open spaces.
Porous-coated	The design feature of a type of implant where the metal has small surface openings into which bone or tissue is intended to grow for permanent stabilization.
Posterior	Situated behind or toward the back; opposite of anterior.
Press-fit (see also uncemented)	Describes the fit at the interface of an implant with the surrounding bone; the implant is implanted without cement and is tightly "pressed" or impacted into the patient’s bone.
Primary	Initial or first; in joint replacement, this term is used to indicate the first surgery to repair or replace a joint as opposed to a revision surgery which replaces or revises an implant.
Process	A slender projecting point; Latin, processus.
Prognosis	Replacement of a missing part by an artificial substitute. An artificial organ or part.
Pronate	To turn palm downward (opposite: supinate).
Prone	Lying with face downward (opposite: supine).
Prosthesis	Replacement of a missing part by an artificial substitute. An artificial organ or part.
Protract	To extend forward or outward; opposite of retract.
Proximal	Nearest; opposite of distal.
PS	Posterior Stabilized; a posterior stabilized knee is a type of semiconstrained total knee system that compensates for a deficient or absent posterior cruciate ligament through its surface geometry (its design minimizes forward and backward movement of the knee and substitutes for the function of the ligament).
Pseudarthrosis	A false joint developing after a fracture that has not united.
Pseudo	A prefix signifying "false.
PT	Premier Total
Pubis	Pubic bone
R
Radiolucent	Allowing x-rays to pass through, radiolucent areas appear dark on x-rays.
Radius	A bone of the forearm.
Ream, reaming	A verb meaning to gouge out holes or enlarge holes already made, in orthopedic surgery, bones need to be reamed to allow for the implantation of a prosthesis.
Recurvatum	Hyperextension of the knee.
Reduction	Restoration to normal position.
Retract	To pull back; opposite of protract.
retrieve, retrieved, retrieval	To remove an implant from a patient.
Retro	Prefix meaning behind.
Retroflexion	A backward bending of one part of an organ on another portion; Opposite of anteflexion.
Retroversion	A backward turning; the entire organ is turned backward; opposite of anteversion.
Revision	In orthopedic surgery, this term indicates a subsequent surgery to alter, replace or remove an implant.
Roentgenogram	A photograph made by means of roentgen rays or x-rays. The rays are named in honor of their discoverer.
Roentgenoscopy	Examination by means of a fluoroscope.
ROM (range of motion)	The area through which a joint may be moved in all planes, measured in degrees. The greater the ROM, the more flexible the joint. One of the goals of joint replacement is to improve a patient’s ROM in the joint that may have been lost to arthritis, trauma or deformity.
Rotation	The act of turning about a centrally located length axis.
S
Sac	Any bag-like organ.
Sacrum	Five fused vertebrae below the last lumbar vertebra.
Sagittal	Pertaining to the median vertical plane of the body.
Scapula	The shoulder blade.
Scoliosis	Lateral abnormal curvature of the spine.
Semilunar	Shaped like a half moon.
Septic	Infection due to presence of pathogenlc organisms.
Serrated	Having a saw-tooth edge.
Serum	Clear portion of any animal fluid.
Shear	A biomechanical term meaning a load applied parallel to the surface of a structure; shear strength is the amount of resistance in a material to angular deformation (bending) resulting from shear forces.
Shell	The acetabular component, the part of a hip replacement system that serves for the hip socket.
Sinterlock	A term trademarked by Zimmer which describes a bonding process.
Sinus	A cavity
Skeleton	The hard framework of the body. The bones of the body collectively.
Spinous	A spine-like process; Latin adjective, spinatus.
SS	Stainless Steel
Stem (see also implant, prosthesis)	A device (or tissue or substance) that is transferred, grafted, or inserted into a living body.
Sterile	Clean and free from all living micro-organisms.
Sternum	The breast bone
Sub	Prefix meaning "below" or "beneath".
Subclavian	Beneath the clavicle
Subluxation	A partial or incomplete dislocation.
Submaxillary	Beneath the maxilla
Subscapular	Beneath the scapula
Subsidence	The settling of a prosthesis after implantation; it is determined by comparing x-rays immediately after surgery to x-rays taken at a later date. Subsidence is a sure sign of loosening of an implant.
Superior	Higher; opposite of inferior; superioris, a Latin form of the adjective.
Supinate	To turn the palm of the hand upward (opposite: pronate).
Supine	Lying flat on the back (opposite: prone).
Supra	Prefix meaning "above;" super has same meaning; opposite of sub.
Surgical pearls	Expert surgical techniques or tips developed by senior surgeons, often for particular implants or procedures.
Surgical technique	A series of steps required to complete a surgical procedure (or operation).
Symphysis	A growing together.
Synovectomy	An immovable joint.
Synovia	A union of bones by means of cartilage.
Synovial Membrane	A thin tissue that lines the capsule surrounding the joint.
T
Talus	The ankle; a bone of the ankle. The tarsal bone articulating with the distal tibia and fibula.
Tarsus	(1) The instep; the seven bones forming the back portion of the foot (2) Connective tissue framework of the eyelids.
Telesession	An instructional course or lecture provided by one-way video, often a telesession consists of an expert surgeon discussing and/or demonstrating specific techniques or characteristics of an implant system.
Template	An outline used to trace bones in order to standardize its form; surgeons use templates of implants to measure against a patient’s x-rays to select the best size and best design for the patient’s anatomy and surgical needs.
Tendon	Fibrous connective tissue serving for the attachment of muscles to bones and other parts. Syn. - sinew.
Tensile strength	A biomechanical measurement of the amount of stress required to cause a given material to fail.
Thoracic	Pertaining to the chest; thoracico or thoraco, containing forms.
Ti	The abbreviation for Titanium, a metal often used in implants.
Ti-6Al-4V	Titanium Aluminum Vanadium Composition (metal alloy), used in many of Zimmer implants.
Tibia	Latin name of shin bone. Larger bone in the lower leg. Pertaining to the tibia; Latin adjective, tibialis.
Tissue	A collection of similar cells specialized to perform a particular function.
Titanium	A metal often used in the manufacture of orthopedic devices or implants. It has good fatigue, wear and strength characteristics and is often combined with other metals in alloys which enhance desirable characteristics.
Trabecular	A type of mature bone commonly found at the ends of bones, it is composed of a latticework of bony plates and columns. Its structure gives trabecular bone a great deal of strength despite having less bony material than cortical bone.
Trochanter	Either of two bony processes of the upper femoral shaft for muscle attachment.
Trochlear groove	The articular portion of the anterior surface of the distal femur (the front-facing notch at the lowest part of the femur where the femur joins the knee joint, this groove provides a shallow depression where the patella slides as the knee articulates).
Tubercle	A small rounded elevation of eminence on a bone.
Tuberosity	Broad eminence on a bone.
UHMWPE (see also polyethylene, plastic)	Ultra-High Molecular Weight Polyethylene, a type of polyethylene with superior wear properties, very commonly used in orthopedic devices.
U
Ulna	The inner and larger bone or the forearm; In the correct anatomic position, palms forward, the inner and larger bone of the forearm, between the wrist and the elbow, on the side opposite the thumb.
Ultra-congruent (see also congruent)	Highly congruent, contains a high degree of constraint between two articular implants.
Uncemented (see also press-fit)	A prosthesis that is implanted without cement.
UNI	Unicompartmental knee (also can be the abbreviation for unilateral).
Unilateral (see also uni)	One-sided, affecting only one-side (ex. a unilateral knee replacement would replace just one knee, not both).
V
Valgus	A term denoting position meaning bent outward (knock-knee) or twisted, applied especially to deformities in which a part is bent outward. Also increased femoral head-neck angle.
Value-added services	This is a broad term that encompasses systems that help orthopedic customers (surgeons and hospitals) meet the demands of managed care, these systems are not directly related to orthopedic implants.
Varus	(1) Turned inward; bowlegged. (2) A condition in which a clubfooted person walks on outer border of the foot. Also, decreased femoral head-neck angle.
Vastus	Wide or great.
Vertex	The summit or apex.
Viscous	Sticky or gummy, thick fluid.
Vitreous	Glassy
Voluntary	Performed in accordance with the will; opposite of involuntary.
W
Wear	The loss of material from solid surfaces due to mechanical abrasion.