Acetabulum (ăs-ĕ-TĂB-yŭ-lŭm): The socket of the hip bone, into which the head of the femur fits. (Chapter 13.4)

Acromion (ă-KRŌ-mē-ŏn): An extension of the scapula that forms the high point of the shoulder. (Chapter 13.4)

Anterior cruciate ligament (ăn-TĪR-ē-ŏr KRŪ-shē-āt LĬG-ă-mĕnt) (ACL): A ligament in the knee joint that connects the femur to the tibia and crosses in front of the PCL that provides stability to the knee. (Chapter 13.4)

Arthritis (är-THRĪ-tĭs): A general term for conditions affecting the joints and surrounding tissues, leading to pain, swelling, stiffness, and limited movement. It includes various types such as osteoarthritis and rheumatoid arthritis. (Chapter 13.6)

Arthrocentesis (ar-thrō-sen-TĒ-sĭs): A surgical puncture to aspirate fluid from a joint, such as the knee. (Chapter 13.7)

Arthrodesis (ar-THROD-ĕ-sĭs): The surgical immobilization of a joint by fusion of the adjacent bones. (Chapter 13.7)

Arthroplasty (AR-thrŏ-plas-tē): Surgical repair of a joint. (Chapter 13.7)

Arthroscopy (är-THRŌ-skō-pē): A common procedure performed by orthopedic surgeons to view the inside of a joint to diagnose and/or to repair joint problems. (Chapter 13.7)

Articular disks (är-TĬK-yŭ-lăr dĭsks): Fibrocartilage structures in some synovial joints that act as cushions and improve the fit between the bones. (Chapter 13.4)

Below-the-knee amputation (bĭ-lō-thē-nē ăm-pyū-TĀ-shŏn) (BKA): A procedure performed by an orthopedic surgeon who removes the foot, ankle, part of the tibia, fibula, and corresponding soft tissue structures. (Chapter 13.7)

Body (bŏd-ē): The middle portion of the sternum (Chapter 13.4)

Bone mineral density (bōn mĭn-ĕr-ăl dĕn-sĭ-tē): A test that measures calcium and other minerals in bone. (Chapter 13.7)

Bursa (BŬR-să): A small fluid-filled sac that acts as a cushion between a bone and other moving parts, such as muscles, tendons, or skin. (Chapter 13.4)

Bursectomy (bŭr-SĔK-tō-mē): Surgical removal of a bursa. (Chapter 13.4)

Bursitis (bŭr-SĪ-tĭs): Inflammation of a bursa, usually occurring in the knee, elbow, or shoulder. (Chapter 13.4)

Calcaneus (kăl-KĀ-nē-ŭs): The heel bone. (Chapter 13.4)

Calcium (KĂL-sē-ŭm) (Ca+): A mineral essential for developing and maintaining healthy bones and teeth. (Chapter 13.4)

Carpals (KĂR-pălz): The bones of the wrist. (Chapter 13.4)

Cartilage (KĂR-tĭ-lĭj): A resilient and smooth elastic tissue that covers and protects the ends of bones at joints. (Chapter 13.4)

Cartilaginous joints (kär-tĭ-LĂJ-ĭ-nŭs joints): Joints where bones are connected by cartilage, allowing more movement than fibrous joints but less than synovial joints. (Chapter 13.4)

Cervical (SŬR-vĭ-kăl): Pertaining to the neck or the cervical vertebrae in the neck region. (Chapter 13.4)

Clavicle (KLĂV-ĭ-kŭl): The collarbone, a long bone that serves as a strut between the shoulder blade and the sternum. (Chapter 13.4)

Closed or simple fracture (klōzd ōr sĭm-pŭl): A type of bone fracture where the skin over the fracture site remains intact, and the bone does not pierce through the skin. (Chapter 13.6)

Coccyx (KŎK-sĭks): The tailbone, formed by the fusion of coccygeal vertebrae. (Chapter 13.4)

Comminuted (kŏm-ĭ-nū-tĕd): A bone is crushed into pieces. (Chapter 13.6)

Cranioplasty (KRĀ-nē-ō-plăs-tē): Surgical repair of the skull. (Chapter 13.4)

Craniotomy (krā-nē-ŌT-ō-mē): A surgical procedure involving an incision through the cranium to access the brain. (Chapter 13.4)

Cranium (KRĀ-nē-ŭm): The skull, especially the part encasing the brain. (Chapter 13.4)

Crepitus (krĕp-ĭ-tŭs): Describes a popping, clicking, or crackling sound when moving a joint that is associated with osteoarthritis. It typically reflects air movement in the joint and is harmless. (Chapter 13.6)

DEXA scan (DĔK-să skăn): Shortened name for a central dual energy X-ray absorptiometry scan. These scans use radiation to measure how much calcium and other minerals are in a specific area of the bone. (Chapter 13.7)

Diskectomy (dĭs-KEK-tŏ-mē): Surgical removal of an intervertebral disk. (Chapter 13.4)

Diskitis (dĭs-KĪ-tĭs): Inflammation of an intervertebral disk. (Chapter 13.4)

Dislocation (dĭs-lō-KĀ-shŏn): A condition where the bones in a joint become displaced from their normal alignment. (Chapter 13.4)

Doctor of Osteopathic Medicine (dŏk-tŏr ŏf ŏs-tē-ŏ-PĂTH-ĭk mĕd-ĭ-sĭn (DO): A medical specialist who uses a whole-person approach to help prevent illness and injury by looking beyond symptoms to understand how lifestyle and environmental factors impact a person’s well-being. They practice medicine according to science and technology, but also consider options to complement medications and surgery. (Chapter 13.7)

Ethmoid (ĔTH-moid): Related to the ethmoid bone, located between the eyes and forming part of the nasal cavity. (Chapter 13.4)

False ribs (FÔLS rĭbz): Ribs 8-10, which are connected to the sternum via cartilage. (Chapter 13.4)

Femur (FĒ-mŭr): The thigh bone, the longest and strongest bone in the body. (Chapter 13.4)

Fibrous joints (FĪ-brŭs joints): Joints where bones are joined by fibrous tissue, typically allowing very little movement. (Chapter 13.4)

Fibula (FĬB-yŭ-lă): The smaller and thinner bone of the lower leg located on the lateral side. (Chapter 13.4)

Floating ribs (FLŌ-ă-tĭng rĭbz): The last two pairs of ribs, which are not attached to the sternum. (Chapter 13.4)

Fracture (FRĂK-chŭr): A medical condition where there is a break in the continuity of the bone. It can range from minor cracks to complete breaks and can occur in any bone in the body.  (Chapter 13.6)

Frontal (FRŬN-tăl): Pertaining to the forehead or the frontal bone of the skull. (Chapter 13.4)

Gout (gowt): A type of inflammatory arthritis that causes pain and swelling in the joints, usually as flares that last for one or two weeks and then resolve. Gout flares often begin in the big toe or a lower limb when high levels of serum uric acid build up in the body. (Chapter 13.6)

Greenstick (grēn-stĭk): Bone is partially broken, a condition that occurs in children. (Chapter 13.6)

Hallux (HĂL-lŭks): The big toe. (Chapter 13.4)

Herniated disk (hûr-nē-Ā-tĭd dĭsk): A condition where a disk protrudes beyond the normal confines of the vertebrae. (Chapter 13.4)

Humerus (HYŌŌ-mĕr-ŭs): The upper arm bone, extending from the shoulder to the elbow. (Chapter 13.4)

Hyoid (HĪ-oid): A U-shaped bone in the neck that supports the tongue. (Chapter 13.4)

Ilium (ĬL-ē-ŭm): The large, broad bone forming the upper part of each half of the pelvis. (Chapter 13.4)

Impacted (ĭm-păk-tĕd): One fragment of the bone is driven into the other, usually as a result of compression. (Chapter 13.6)

Inferior conchae (ĬN-fēr-ē-ŏr KŎN-kē): Referring to the lowermost scroll-like bones on the lateral walls of the nasal cavity. (Chapter 13.4)

Intercostal (ĭn-tĕr-KŎS-tăl): Located between the ribs. (Chapter 13.4)

Intercostal retractions (ĭn-tĕr-KŎS-tăl rē-trăk-SHŏnz): The inward movement of the muscles between the ribs, typically a sign of respiratory distress. (Chapter 13.4)

Intervertebral disks (ĭn-tĕr-VĔRT-ĕ-brăl dĭsks): Pertaining to the space or structure between two vertebrae. (Chapter 13.4)

Ischium (ĬS-kē-ŭm): The curved bone forming the base of each half of the pelvis. (Chapter 13.4)

Joints (jōyntz): The locations where two or more bones meet, allowing for movement or stability in the skeleton. (Chapter 13.4)

Kyphosis (kī-FŌ-sĭs): An excessive outward curvature of the spine, causing a hunching of the back. It can result from degenerative diseases, developmental problems, osteoporosis, or trauma. (Chapter 13.6)

Lacrimal (LĂK-rĭ-măl): Related to the lacrimal bones, small bones forming part of the eye socket. (Chapter 13.4)

Laminectomy (lăm-ĭ-NĔK-tō-mē): Surgical removal of a portion of the vertebral bone called the lamina. (Chapter 13.4)

Lateral collateral ligament (LĂT-ĕr-ăl KŎL-ă-TĔR-ăl LĬG-ă-mĕnt) (LCL): A ligament on the outer side of the knee joint connecting the femur to the fibula. (Chapter 13.4)

Lateral malleolus (LĂT-ĕr-ăl MĂL-ē-ŏ-lŭs): The bony prominence on the outside of the ankle, formed by the lower end of the fibula. (Chapter 13.4)

Ligaments (LĬG-ă-mĕnts): Bands of tough, fibrous connective tissue that connect bones to other bones at joints. (Chapter 13.4)

Lordosis (lor-DŌ-sĭs): An excessive inward curvature of the spine, often affecting the lower back. It can be caused by obesity, poor posture, or other underlying conditions. (Chapter 13.6)

Lumbar (LŬM-bär): Related to the lower back or the lumbar vertebrae. (Chapter 13.4)

Lupus (lū-pŭs): Common name for systemic lupus erythematosus; a chronic autoimmune disease that can affect many parts of the body. (Chapter 13.6)

Mandible (MĂN-dĭ-bŭl): The lower jawbone. (Chapter 13.4)

Manubrium (mă-NŪ-brē-ŭm): The upper part of the sternum. (Chapter 13.4)

Maxillary (MĂK-sĭ-lăr-ē): Pertaining to the maxilla or the upper jawbone. (Chapter 13.4)

Medial collateral ligament (MĒ-dē-ăl KŎL-ă-TĔR-ăl LĬG-ă-mĕnt) (MCL): A ligament on the inner side of the knee, connecting the femur to the tibia. (Chapter 13.4)

Medial malleolus (MĒ -dē-ăl MĂL-ē-ŏ-lŭs): The bony prominence on the inside of the ankle, formed by the lower end of the tibia. (Chapter 13.4)

Meniscectomy (mĕn-ĭ-SĔK-tō-mē): Surgical removal of all or part of a torn meniscus. (Chapter 13.4)

Meniscitis (men-ĭ-SĪT-ĭs): Inflammation of a meniscus, typically in the knee. (Chapter 13.4)

Meniscus (mĕ-NĬS-kŭs): A C-shaped piece of cartilage in the knee joint that acts as a shock absorber between the femur and tibia. (Chapter 13.4)

Metacarpals (mĕt-ă-KĂR-pălz): The bones of the hand between the wrist and the fingers. (Chapter 13.4)

Metatarsals (mĕt-ă-TĂR-sălz): The bones in the midfoot and forefoot. (Chapter 13.4)

Myeloma (mī-ĕ-LŌ-mă): A type of cancer that originates in the bone marrow. (Chapter 13.4)

Nasal (NĀ-zăl): Pertaining to the nasal bones of the nose. (Chapter 13.4)

Oblique (ō-blēk): Bone is broken at an angle. (Chapter 13.6)

Occipital (ŏk-SĬP-ĭ-tăl): Pertaining to the occipital bone at the back and base of the skull. (Chapter 13.4)

Open or compound fracture (ō-pĕn ōr kŏm-pound): A severe type of bone fracture where the broken bone pierces through the skin, creating an open wound. This type increases the risk of infection. (Chapter 13.6)

Open reduction and internal fixation (ō-pĕn rĭ-DŬK-shŏn ănd ĭn-tĕr-năl fĭk-SĀ-shŏn) (ORIF): A type of surgery used to stabilize and heal a broken bone using screws, plates, wires, or nails to reconnect bones. (Chapter 13.7)

Orthopedics (or-thŏ-pē-dĭks): A branch of medicine that treats disorders and diseases related to the musculoskeletal system. (Chapter 13.7)

Orthopedists (or-thŏ-pē-dĭsts): Medical doctors who specialize in the prevention, diagnosis, treatment, and surgery of disorders and diseases related to the musculoskeletal system. (Chapter 13.7)

Osteoarthritis (ŏs-tē-ō-är-THRĪ-tĭs): A degenerative joint disease in which the tissues in the joint break down over several years. It is the most common type of arthritis and frequently occurs as people age. (Chapter 13.6)

Osteoblasts (ŏs-tē-ō-BLĀSTS): Cells that form new bone tissue. (Chapter 13.4)

Osteoclasts (ŏs-tē-ō-KLĀSTS): Cells that break down and resorb bone tissue. (Chapter 13.4)

Osteocytes (ŏs-tē-Ō-SĪTS): Mature bone cells that maintain bone tissue. (Chapter 13.4)

Osteomalacia (ŏs-tē-ō-mă-LĀ-sē-ă): Softening of bones due to a deficiency of vitamin D or calcium. (Chapter 13.4)

Osteomyelitis (ŏs-tē-ō-mī-ĕ-LĪT-ĭs): Inflammation of bone and bone marrow, usually caused by infection. (Chapter 13.4, Chapter 13.6)

Osteonecrosis (ŏs-tē-ō-nĕ-KRŌ-sĭs): Death of bone tissue due to a lack of blood supply. (Chapter 13.4, Chapter 13.7)

Osteopathy (ŏs-tē-ŏ-pă-thē): A branch of medical practice that emphasizes the treatment of medical disorders through the manipulation and massage of the bones, joints, and muscles. (Chapter 13.7)

Osteopenia (ŏs-tē-ō-PĒ-nē-ă): Reduced bone mass of lesser severity than osteoporosis. (Chapter 13.4, Chapter 13.6)

Osteoporosis (ŏs-tē-ō-pō-RŌ-sĭs): A condition where bones become weak and brittle, often due to loss of tissue as a result of hormonal changes or deficiency of calcium or vitamin D. It increases the risk of fractures. (Chapter 13.4, Chapter 13.6)

Osteosarcoma (ŏs-tē-ō-sär-KŌ-mă): A type of malignant bone tumor. (Chapter 13.4)

Palatine (PĂL-ă-tīn): Related to the palatine bones of the skull, forming parts of the nasal cavity and hard palate. (Chapter 13.4)

Parietal (pă-rī-ĔT-ăl): Pertaining to the parietal bones of the skull, located at the sides and top of the cranium. (Chapter 13.4)

Patella (pă-TĔL-ă): The kneecap, a small bone in front of the knee joint. (Chapter 13.4)

Pelvis (PĔL-vĭs): The large bony structure near the base of the spine which includes the two hip bones, the sacrum, and the coccyx to which the legs are attached. (Chapter 13.4)

Phalanges (fă-LĂN-jēz): The bones of the fingers and toes. (Chapter 13.4)

Phalanx (FĂ-lăngks): A single bone of the fingers or toes. (Chapter 13.4)

Posterior cruciate ligament (pŏs-TĪR-ē-ŏr KRŪ-shē-āt LĬG-ă-mĕnt) (PCL): A ligament in the knee that crosses behind the ACL and connects the femur to the tibia. (Chapter 13.4)

Prosthesis (PRŌS-thē-sĭs): An artificial body part. (Chapter 13.7)

Pubic symphysis (PYŪ-bĭk SĬM-fĭ-sĭs): The joint between the two pubic bones at the front of the pelvis. (Chapter 13.4)

Pubis (PYŪ-bĭs): The front part of the pelvic girdle, situated at the anterior part of the pelvis. (Chapter 13.4)

Radiologist (RĀ-dē-ŏ-jĭst): A physician who specializes in diagnosing and treating injuries and diseases using medical imaging (radiology) procedures such as X-rays, computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine, positron emission tomography (PET), and ultrasound. (Chapter 13.7)

Radiology technologist (rā-dē-ŎL-ŏ-jē tĕk-nŎL-ŏ-jĭst): Commonly called an X-ray tech, is a health care professional who is specially trained to perform medical imaging like X-rays, CT scans, MRIs, and PET scans. (Chapter 13.7)

Radius (RĀ-dē-ŭs): The lateral bone of the forearm, on the same side as the thumb. (Chapter 13.4)

Rheumatoid arthritis (rū-mă-toid är-thrī-tĭs) (RA): A chronic autoimmune disease that affects the joints. (Chapter 13.6)

Rheumatologists (rū-mă-tŏl-ŏ-jĭsts): Physicians who specialize in the diagnosis and treatment of musculoskeletal diseases and systemic autoimmune conditions commonly referred to as rheumatic diseases. (Chapter 13.7)

Rheumatology (rū-mă-tŏl-ŏ-jē): The study of inflammatory or infectious conditions of the joints and other parts of the musculoskeletal system. (Chapter 13.7)

Rickets (RĬK-ĭts): A disease in children caused by extreme and prolonged vitamin D deficiency. (Chapter 13.6)

Sacrum (SĀ-krŭm): A triangular bone at the base of the spine, formed by the fusion of sacral vertebrae. (Chapter 13.4)

Scapula (SKĂP-yŭ-lă): The shoulder blade, a large triangular bone on the back of the shoulder. (Chapter 13.4)

Scoliosis (skō-lē-Ō-sĭs): An abnormal lateral curvature of the spine, often diagnosed in childhood or adolescence. It can vary in severity and may require treatments such as bracing or surgery in more severe cases. (Chapter 13.6)

Sphenoid (SFĒ-noid): Pertaining to the sphenoid bone, a complex bone at the base of the skull. (Chapter 13.4)

Spiral (spī-răl): Bone has twisted apart. (Chapter 13.6)

Spondylosis (spŏn-dĭ-LŌ-sĭs): A painful condition of the spine resulting from the degeneration of intervertebral disks. (Chapter 13.4)

Sternum (STŬR-nŭm): The breastbone, a long flat bone in the center of the chest. (Chapter 13.4)

Stress (strĕs): Small crack in a bone. (Chapter 13.6)

Synovectomy (sĭn-ō-VĔK-tō-mē): Surgical removal of the synovial membrane from a joint. (Chapter 13.4)

Synovial fluid (sĭ-NŌ-vē-ăl FLŌŌ-id): A viscous fluid found in the cavities of synovial joints, reducing friction between the articular cartilage during movement. (Chapter 13.4)

Synovial joints (sĭ-NŌ-vē-ăl joints): Highly movable joints where two bones are separated by a joint cavity containing synovial fluid. (Chapter 13.4)

Synovial membrane (sĭ-NŌ-vē-ăl MĔM-brān): The lining of the inner surface of capsules of synovial joints, secreting synovial fluid for lubrication. (Chapter 13.4)

Systemic lupus erythematosus (sĭs-tĕm-ĭk lū-pŭs ĕr-ĕth-ĕm-ă-tō-sŭs): Commonly referred to as lupus; a chronic autoimmune disease that can affect many parts of the body. (Chapter 13.6)

Tarsals (TĂR-sălz): The bones in the rear part of the foot (the heel and the instep). (Chapter 13.4)

Temporal (TĔM-pō-răl): Related to the temporal bones of the skull, located at the lower sides. (Chapter 13.4)

Temporomandibular joint (tĕm-pō-rō-MĂN-dĭ-bŭ-lăr) (TMJ): The hinge joint connecting the temporal bone of the skull with the mandible. (Chapter 13.4)

Tendon (TĔN-dŏn): A fibrous connective tissue that attaches muscle to bone. (Chapter 13.4)

Thoracic (thō-RĂS-ĭk): Pertaining to the thorax or the thoracic vertebrae in the upper back. (Chapter 13.4)

Tibia (TĬB-ē-ă): The shin bone, the larger and stronger of the two bones in the lower leg located on the medial side. (Chapter 13.4)

Total hip arthroplasty (tō-tăl hĭp är-thrŏ-plăs-tē) (THA): Also called a total hip replacement (THR), the replacement of the head of the femur and acetabulum with replacement parts that are either metal, ceramic, or hard plastic. (Chapter 13.7)

Total hip replacement (tō-tăl hĭp rē-plās-mĕnt) (THR): Also called a total hip arthroplasty (THA), the replacement of the head of the femur and acetabulum with replacement parts that are either metal, ceramic, or hard plastic. (Chapter 13.7)

Total knee arthroplasty (tō-tăl nē är-thrŏ-plăs-tē) (TKA): Also called total knee replacement (TKR), surgical removal of worn surfaces of the knee joint due to severe osteoarthritis. (Chapter 13.7)

Total knee replacement (tō-tăl nē rē-plās-mĕnt) (TKR): Also called total knee arthroplasty (TKA), surgical removal of worn surfaces of the knee joint due to severe osteoarthritis. (Chapter 13.7)

Transverse (trăns-vûrs): Bone is broken straight across. (Chapter 13.6)

True ribs (TRŌŌ rĭbz): The first seven pairs of ribs, which attach directly to the sternum. (Chapter 13.4)

Ulna (ŬL-nă): The medial bone of the forearm, on the same side as the pinky finger. (Chapter 13.4)

Vertebrae (VŬR-tĭ-brā): The individual bones that make up the vertebral column (spine). (Chapter 13.4)

Vertebral column (vŭr-TĒ-brăl KŌL-ŭm): The spinal column or backbone, consisting of multiple vertebrae. (Chapter 13.4)

Vomer (VŌ-mĕr): A thin, flat bone forming the lower part of the nasal septum. (Chapter 13.4)

Xiphoid process (ZĪ-foid PRŌ-sĕs): The small, cartilaginous projection at the lower end of the sternum. (Chapter 13.4)

X-rays (ĕks-rāz): Use a form of radiation that travels through the body and strikes an X-ray detector, forming an image that represents the “shadows” of objects inside the body. (Chapter 13.7)

Zygomatic (zī-gō-MĂT-ĭk): Related to the cheekbone or zygomatic bone. (Chapter 13.4)