Orthopaedic Glossary
Plain-language definitions of common orthopaedic and musculoskeletal terms.
A
ACL (Anterior Cruciate Ligament)
A key ligament in the center of the knee that prevents the shinbone from sliding forward. ACL tears are common sports injuries.
Learn more →Arthritis
Inflammation of one or more joints, causing pain and stiffness that can worsen with age. Osteoarthritis is the most common form in orthopaedics.
Learn more →Arthroscopy
A minimally invasive surgical procedure in which a small camera is inserted into a joint through a tiny incision to diagnose and treat problems.
Learn more →Arthroplasty
The surgical reconstruction or replacement of a joint. Total knee arthroplasty (TKA) and total hip arthroplasty (THA) are common examples.
Learn more →B
Bone Graft
Transplanted bone tissue used to repair or rebuild diseased or damaged bones. Can come from the patient (autograft), a donor (allograft), or synthetic material.
Bone Spur (Osteophyte)
A bony projection that forms along the edges of bones, often where bones meet each other in joints. Common in osteoarthritis.
Bursitis
Inflammation of the fluid-filled sacs (bursae) that cushion bones, tendons, and muscles near joints. Common in the shoulder, elbow, and hip.
C
Cartilage
Smooth, rubbery tissue that covers the ends of bones in joints. It allows bones to glide over each other and absorbs shock during movement.
Carpal Tunnel
A narrow passageway in the wrist formed by bones and ligaments. The median nerve passes through it. Compression causes carpal tunnel syndrome.
Learn more →Cortisone Injection
An injection of corticosteroid medication into a joint to reduce inflammation and pain. Provides temporary relief (weeks to months).
CT Scan (Computed Tomography)
An imaging test that uses X-rays and computers to create detailed cross-sectional images of bones and joints. Often used for surgical planning.
D
Degenerative Disc Disease
A condition in which spinal discs break down with age, causing pain and reduced flexibility. Not truly a "disease" but a natural aging process.
Dislocation
An injury in which a bone is forced out of its normal position in a joint. Common in shoulders, fingers, and kneecaps.
DVT (Deep Vein Thrombosis)
A blood clot that forms in a deep vein, usually in the leg. A potential complication after surgery that requires blood-thinning medication to prevent.
F
Femur
The thighbone - the longest and strongest bone in the body. It connects the hip to the knee.
Fracture
A break in a bone. Fractures range from hairline cracks (stress fractures) to complete breaks requiring surgical repair.
Frozen Shoulder (Adhesive Capsulitis)
A condition characterized by stiffness and pain in the shoulder joint. Typically develops gradually and resolves over 1-3 years.
G
Graft
Tissue transplanted from one part of the body to another (autograft) or from a donor (allograft). Used in ligament reconstruction and bone repair.
H
Herniated Disc
A condition where the soft center of a spinal disc pushes through a crack in the tougher exterior, potentially pressing on nearby nerves.
Learn more →I
Impingement
A condition where tendons or soft tissue are pinched between bones during movement. Common in the shoulder (subacromial impingement) and hip (femoroacetabular impingement).
J
Joint Replacement
Surgery to remove a damaged joint and replace it with an artificial one (prosthesis). Most common in the knee, hip, and shoulder.
Learn more →L
Labrum
A ring of fibrous cartilage that surrounds the socket in both the shoulder (glenoid labrum) and hip (acetabular labrum). Tears can cause pain and instability.
Ligament
A tough band of fibrous tissue that connects bones to other bones and provides stability to joints. The ACL, MCL, PCL, and LCL stabilize the knee.
M
Meniscus
A C-shaped piece of cartilage in the knee that acts as a shock absorber between the thighbone and shinbone. Each knee has two menisci.
Learn more →MRI (Magnetic Resonance Imaging)
An imaging technique that uses magnetic fields and radio waves to create detailed images of soft tissues, including muscles, tendons, ligaments, and cartilage.
N
NPI (National Provider Identifier)
A unique 10-digit identification number assigned to healthcare providers in the United States. Used for billing and identification purposes.
O
Orthopaedic Surgeon
A medical doctor (MD or DO) who specializes in the diagnosis, treatment, and prevention of conditions affecting the musculoskeletal system - bones, joints, ligaments, tendons, and muscles.
Osteoporosis
A condition that weakens bones, making them fragile and more likely to break. Common in postmenopausal women and older adults.
P
Physical Therapy (PT)
Treatment that uses exercises, stretches, and manual techniques to restore movement and function after injury or surgery. Often the first-line treatment for musculoskeletal problems.
Plantar Fascia
A thick band of tissue on the bottom of the foot connecting the heel bone to the toes. Inflammation causes plantar fasciitis.
Learn more →Prosthesis
An artificial device that replaces a missing body part or joint. In orthopaedics, usually refers to joint replacement implants.
R
Rotator Cuff
A group of four muscles and tendons that stabilize the shoulder joint and allow arm rotation. Tears are a common source of shoulder pain.
Learn more →S
Sciatica
Pain that radiates along the sciatic nerve from the lower back through the hip and down the leg. Usually caused by a herniated disc or bone spur pressing on the nerve.
Scoliosis
A sideways curvature of the spine that most often occurs during the growth spurt before puberty. Treatment ranges from observation to bracing to surgery.
Learn more →Spinal Fusion
A surgical procedure that permanently joins two or more vertebrae, eliminating motion between them to treat instability or deformity.
Learn more →Spinal Stenosis
Narrowing of the spaces within the spine, which can put pressure on the spinal cord and nerves. Most common in the lower back and neck.
Sports Medicine
A branch of orthopaedics focused on treating and preventing injuries related to sports and exercise, including ACL tears, rotator cuff injuries, and stress fractures.
T
Tendon
A tough cord of fibrous tissue that connects muscle to bone. Tendons transmit the force of muscle contractions to move bones.
Tendinitis
Inflammation or irritation of a tendon, usually caused by repetitive motion. Common types include Achilles tendinitis, tennis elbow, and golfer's elbow.
Total Joint Replacement
Surgery to replace the entire damaged joint with artificial components. The most successful and common operations in orthopaedics.
X
X-Ray
A quick, painless imaging test that uses electromagnetic radiation to produce images of bones. Usually the first imaging test ordered for musculoskeletal problems.
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