• Glossary of Orthopaedic Words - A

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    • Movement of an extremity away from the body.


    • A pus-filled area that affects skin or organs.


    • The receptacle for the head of the femur; formed by the ilium, ischium, and pubis.

    Achilles tendinitis

    • Inflammation of the Achilles tendon often caused by increased activity, improper footwear, or tight hamstrings.

    Acquired immune deficiency syndrome (AIDS)

    • A disease that is characterized by profound immune system suppression and associated with opportunistic infections, secondary neoplasms, and neurologic manifestations. Caused by the human immunodeficiency virus (HIV).
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    • Overgrowth of the bones of the hands, feet, and face.

    Acromion process

    • A lateral condensation of bone that is the attachment site for the lateral and posterior two thirds of the deltoid muscle.


    • The insertion of needles into precisely defined points on the body; thought to realign imbalances of yin-yang and qi and thereby bring harmony to the "climate" of an individual


    • Movement of an extremity toward the body.


    • Enlargement of the glands.
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    Adhesive capsulitis

    • Self-limiting condition resulting from any inflammatory process about the shoulder in which capsular scar tissue is produced, resulting in pain and limited range of motion; also called frozen shoulder

    Aerobic exercise

    • Exercise that uses oxidative metabolic pathways to provide energy


    • Muscles that produce body movement in the same direction.


    • A substance that produces an allergic reaction.


    • Biologic tissue from a cadaver that is used to surgically replace damaged tissue
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    Alternative medicine

    • A wide spectrum of treatments-many finding support from collective anecdotal evidence-that is not considered standard therapy because of the lack of a scientific rationale, clinical evidence, or a favorable historic tradition

    Ambulatory condition

    • Assessment of the injured athlete where the athlete is seen by the athletic trainer at some point following the injury.


    • Loss of the menstrual cycle. Considered part of the female athlete triad.

    Anabolic steroids

    • Synthetic derivatives of testosterone originally developed to treat hypogonadism in men, lost muscle mass in patients debilitated by illness, and severe anemia. Sometimes used to enhance muscle-building effects in athletes.

    Anaerobic exercise

    • Exercise of short duration, not requiring the body's utilization of oxygen to make fuel available
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    Anaerobic metabolism

    • Oxygen debt; when the cardiovascular system is unable to meet the needs of the working muscles, the anaerobic metabolism is activated


    • The relief of pain


    • A pain-relieving effect with no loss of consciousness.


    • A violent hypersensitivity reaction, resulting in shock.


    • Chest pain.
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    Ankylosing spondylitis

    • An inflammatory disorder that affects the low back and pelvis and produces stiffness and pain


    • Marked stiffness of a joint typically observed with end-stage arthritis, following a complex intra-articular fracture, delayed treatment of septic arthritis, or severe rheumatoid arthritis

    Annulus fibrosus

    • A region of the intervertebral disk that provides support for the nucleus.

    Anorexia nervosa

    • A nutritional disorder that occurs in as many as 1% of individuals in a vulnerable population in which an individual refuses to maintain body weight over a minimal normal weight for age and height.


    • Muscles that produce body movement in opposing directions.
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    Anterior compartment syndrome

    • Increased soft-tissue pressure in the anterior compartment of the lower leg, resulting in pain, decreased sensation, and muscle paralysis

    Anterior cruciate ligament tears

    • An acute knee injury that occurs when the foot is planted, the knee is flexed, and a valgus force is applied to the knee with the lower leg in external rotation; commonly occurs in sports that require twisting, jumping, and pivoting.

    Anterior superior iliac spine

    • Blunt bony projection on the anterior border of the ilium, forming the anterior end of the iliac crest. Serves as the origin of the sartorius muscle.

    Anterior surface

    • Surface at the front of the body, facing the examiner

    Anteromedial rotatory instability

    • When the medial plateau of the tibia rotates anteriorly and medial joint opening occurs, indicating disruption of the superficial tibia collateral ligament, medial and posteromedial capsular structures, and anterior cruciate ligament
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    Anteroposterior (AP) view

    • Anterior-posterior view in which the x-ray tube is in front and the film cassette is in back. The x-ray beam passes from front to back.


    • A substance that can counteract a poison.


    • Foreign substances that can infiltrate the body, including bacteria, fungi, parasites, toxic chemicals, and abnormal body cells, prompting the production of antibodies that attempt to destroy the substances.


    • A drug that counteracts the effects of histamine; one use is to relieve the symptoms of an allergic reaction.


    • A fever-relieving or -reducing property.
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    Anulus fibrosus

    • The outer ring of fibrous material surrounding the nucleus of the intervertebral disks


    • A broad, fibrous sheet that attaches one muscle to another.


    • A cartilaginous structure at the insertion of major muscle groups into bone that may be susceptible to overuse syndromes and acute fractures in pediatric athletes.


    • Inflammation of the appendix, the small intestinal pouch that extends from the cecum.


    • Irregular heartbeat.
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    • Small tubular branches of the arteries.


    • Aspiration of a joint


    • The surgical fusion of a joint. The procedure removes any remaining articular cartilage and positions the adjacent bones to promote bone growth across a joint. A successful fusion eliminates the joint and stops motion. The usual purpose is pain relief or stabilization of an undependable joint


    • A procedure in which a contrast medium is injected into a joint to outline soft tissues such as the meniscus in the knee or a torn structure such as the rotator cuff in the shoulder. MR arthrography is a technique in which a diluted contrast medium such as gadolinium is injected into a joint to improve the delineation of soft tissues. Standard MRI is obtained following the injection.

    Arthrokinematic motion

    • Vertebral motion that occurs within the joint capsule at the articulations.
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    • procedure to replace or mobilize a joint, typically performed by removing the arthritic surfaces and replacing them with an implant. Total joint arthroplasty is replacement of both sides of the joint. Hemiarthroplasty replaces only one side of a joint


    • A form of minimally invasive surgery in which a fiberoptic camera, the arthroscope, is introduced into an area of the body through a small incision

    Articular cartilage

    • A smooth, glistening surface that covers the ends of bones that articulate with each other to form a joint.


    • Removal of fluids from a body cavity; often done to obtain specimens for analysis


    • A chronic inflammatory disorder of the airways associated with changes in airway hyperresponsiveness.
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    Athlete's foot

    • An infection of the toe web space.

    Athletic trainer

    • A qualified allied healthcare provider who is educated in the management of healthcare problems of athletes.

    Atlantoaxial subluxation (AAS)

    • An orthopaedic problem seen frequently in athletes with Down syndrome that poses a significant risk to athletes participating in sports that involve bodily contact. Joint looseness, ligamentous laxity, or malformation of the vertebrae or surrounding structures causes the C1 vertebra to slip forward and compress the spinal cord, particularly when the neck is in flexion or extension.

    Atlanto-occipital fusion

    • A rare condition consisting of congenital fusion of the ring of the atlas to the occiput; considered an absolute contraindication for contact sports.


    • The first cervical vertebra (C1).
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    • The upper chambers of the heart, composed of the left and right atria.


    • Biologic tissue from the patient's own body that is used to surgically replace damaged tissue

    Autonomic dysreflexia

    • A health concern for athletes with a spinal cord injury above level T8 in which the athlete experiences dizziness, sweating, headaches, and potentially severe hypertension. A plugged urethral catheter is the most common trigger; however, fecal impaction, renal calculi or infections, and pressure sores can also cause the condition.

    Avascular necrosis

    • A condition in which cells die as a result of inadequate blood supply; see also osteonecrosis

    Avulsion fracture

    • A fracture that occurs when a ligament or tendon pulls off a sliver of the bone
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    Avulsion fractures

    • A fracture caused by a violent muscle contraction or sudden passive stretch. Also, pulling off of the osseous insertion or origin in a child.

    Axial compression

    • A force directed along the vertical axis of the cervical spine that is part of almost every serious injury.

    Axial loading

    • A load directed vertically along the axis of the cervical spine during a compression force such as spearing or a head-on collision.


    • The second cervical vertebra (C2).


    • A grade II nerve injury resulting from nerve stretching in which the endoneurium remains intact.
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