Knee Glossary of Terms


Anatomical Axis - Line drawn from the center of the knee through the middle of the femur to the top of the femoral canal

Anterior - Toward the front

Anterior Cruciate Ligament (ACL) - One of the major structural ligaments of the knee providing anteroposterior (front to back) stability

Arthritis - Inflammation of the joint due to infectious, metabolic, constitutional or behavioral causes

Arthroplasty - The surgical repair of a diseased joint

Articulation - The act of motion between two or more bones within a single joint



Bilateral - Pertaining or involving both sides; bilateral knees = left and right knees

Biomechanics - The study of the action of external and internal forces on the living body



Cancellous - The softer, spongy inner matrix of bone

Capsule - Soft tissue envelope which surrounds a joint

Cartilage - A tough, rubbery supportive tissue found on the ends of bones and serving the purpose of reducing friction during movement

Condyle - A rounded prominence at the end of a bone, most often for articulation with another bone

Cortex - The outer layer

Cortical - The harder outer layer of bone

Crepitus - A creaking, squeaking or grinding sound emanating from a joint, most notable the knee joint, upon slowly flexing and extending the joint



Distal - Farthest from the point of origin



Epicondyle - A bony prominence on the condyles serving as a place for attachment for ligaments, tendons and muscles

Extension - The act of straightening a limb

External - One the outside or surface



Femur - The thigh bone, which is the largest and strongest bone in the body

Flexion - The act of bending a limb

Flexion Contracture - Soft tissue tightening resulting in loss of motion in the joint







Inferior - Lower in place or position, situated beneath another, or toward the feet

Internal - Movement toward the inside or midline of the body





Kinematics - The study of motion of the body



Lateral - Away from the median or midline of the body; toward the side

Lateral Collateral Ligament (LCL) - The ligament found on the outer side of the knee



Mechanical Axis - Line drawn from the center of the femoral head, thorugh the center of the knee, to the center of the ankle

Medial - The middle, or toward the middle

Medial Collateral Ligament (MCL) - The ligament found on the inner side of the knee and spanning the joint

Median - The midline of the body

Medullary Canal - The tubular, hollow area within long bones around which marrow is located; also called the intramedullary canal

Meniscus - Crescent shaped cartilage in the knee that acts as a cushion between bones





Osteoarthritis - A form of arthritis caused by chronic degeneration of the cartilage of the joint

Osteochondrosis - A deterioration or inflammation of the bone/cartilage surface

Osteophyte - Bony projections that form along joints



Patella - The kneecap, which is a thick circular-triangular bone that articulates with the femur and covers and protects the anterior articular surface of the knee joint

Patellofemoral Tendon - The tendon at the distal end of the quadriceps muscle group, containing the patella, and which inserts into the tibial tuberosity

Periosteum - A membrane that lines the outer surface of all bones except at the joint and serves as attachment for muscles and tendons

Posterior - Situated behind another structure; the back side

Proximal - Nearest to the point of origin or attachment



Quadriceps - The large four-part extensor muscle at the front of the femur, comprised of the rectus femoris, vastus lateralis, vastus intermedius, and the vastus medialis



Rotation - The act of turning a body part around a centrally located axis



Sagittal - Referring to the median vertical plane of the body

Sterile - Devoid of living organisms

Subluxation - A partial or incomplete dislocation of the joint

Superior - Above, higher



Tendon - A specialized connective tissue which joints muscles to bone

Tibia - The larger, heavier bone of the lower leg; shin bone

Tibial Plateau - The top or proximal portion of the tibia on which the femoral condyles articulate

Tibial Tuberosity - A bony prominence on the proximal anterior portion of the tibia which serves as the insertion of the patellofemoral tendon for the quadriceps

Tubercle - A small, rounded eminence of bone for attachment of tendons

Tuberosity - A broad, rounded eminence of bone where muscles attach





Valgus - "knock knee"

Varus - "bow legged"