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Articular Capsule
In anatomy, a joint capsule or articular capsule is an envelope surrounding a synovial joint. Each joint capsule has two parts: an outer fibrous layer or membrane, and an inner synovial layer or membrane. Membranes Each capsule consists of two layers or membranes: * an outer (fibrous membrane, ''fibrous stratum'') composed of avascular white fibrous tissue * an inner ('' synovial membrane'', ''synovial stratum'') which is a secreting layer On the inside of the capsule, articular cartilage covers the end surfaces of the bones that articulate within that joint. The outer layer is hig ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomy
Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function (biology), function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic research, basic sciences that are applied in medicine. The discipline of anatomy is divided into macroscopic scale, macroscopic and microscopic scale, microscopic. Gross anatomy, Macroscopic anatomy, or gross anatomy, is the examination of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synovial Joint
A synovial joint, also known as diarthrosis, joins bones or cartilage with a fibrous joint capsule that is continuous with the periosteum of the joined bones, constitutes the outer boundary of a synovial cavity, and surrounds the bones' articulating surfaces. This joint unites long bones and permits free bone movement and greater mobility. The synovial cavity/joint is filled with synovial fluid. The joint capsule is made up of an outer layer of fibrous membrane, which keeps the bones together structurally, and an inner layer, the synovial membrane, which seals in the synovial fluid. They are the most common and most movable type of joint in the body of a mammal. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones. Structure Synovial joints contain the following structures: * Synovial cavity: all diarthroses have the characteristic space between the bones that is filled with synovial fluid * Joint capsule: the fibrous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synovial Membrane
The synovial membrane (also known as the synovial stratum, synovium or stratum synoviale) is a specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath. It makes direct contact with the fibrous membrane on the outside surface and with the synovial fluid lubricant on the inside surface. In contact with the synovial fluid at the tissue surface are many rounded macrophage-like synovial cells (type A) and also type B cells, which are also known as fibroblast-like synoviocytes (FLS). Type A cells maintain the synovial fluid by removing wear-and-tear debris. As for the FLS, they produce hyaluronan, as well as other extracellular components in the synovial fluid. Structure The synovial membrane is variable but often has two layers: * The outer layer, or subintima, can be of almost any type of connective tissue – fibrous (dense collagenous type), adipose (fatty; e.g. in intra-articular fat pads) or areolar (loose collagenous typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provide structure and support for the body, and enable animal locomotion, mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple Function (biology), functions. Bone tissue (osseous tissue), which is also called bone in the mass noun, uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix (biology), matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization (biology), mineralization of bone; osteoclasts are involved in the bone resorption, resor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dense Connective Tissue
Dense connective tissue, also called dense fibrous tissue, is a type of connective tissue with fibers as its main matrix element. The fibers are mainly composed of type I collagen. Crowded between the collagen fibers are rows of fibroblasts, fiber-forming cells, that generate the fibers. Dense connective tissue forms strong, rope-like structures such as tendons and ligaments. Tendons attach skeletal muscles to bones; ligaments connect bones to bones at joints. Ligaments are more stretchy and contain more elastic fibers than tendons. Dense connective tissue also make up the lower layers of the skin (dermis), where it is arranged in sheets. Classification It is classified as either dense regular connective tissue or dense irregular connective tissue. See also *Loose connective tissue Loose connective tissue, sometimes called areolar tissue, is a cellular connective tissue with thin and relatively sparse collagen fibers. Its ground substance occupies more volume than the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frozen Shoulder
Adhesive capsulitis, also known as frozen shoulder, is a condition associated with shoulder pain and stiffness. It is a common shoulder ailment that is marked by pain and a loss of range of motion, particularly in external rotation. There is a loss of the ability to move the shoulder, both voluntarily and by others, in multiple directions. The shoulder itself, however, does not generally hurt significantly when touched. Muscle loss around the shoulder may also occur. Onset is gradual over weeks to months. Complications can include fracture of the humerus or biceps tendon rupture. The cause in most cases is unknown. The condition can also occur after injury or surgery to the shoulder. Risk factors include diabetes and thyroid disease. The underlying mechanism involves inflammation and scarring. The diagnosis is generally based on a person's symptoms and a physical exam. The diagnosis may be supported by an MRI. Adhesive capsulitis has been linked to diabetes and hypothyroidism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoulder
The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The shoulder joint, also known as the glenohumeral joint, is the major joint of the shoulder, but can more broadly include the acromioclavicular joint. In human anatomy, the shoulder joint comprises the part of the body where the humerus attaches to the scapula, and the head sits in the glenoid cavity. The shoulder is the group of structures in the region of the joint. The shoulder joint is the main joint of the shoulder. It is a ball and socket joint that allows the arm to rotate in a circular fashion or to hinge out and up away from the body. The joint capsule is a soft tissue envelope that encircles the glenohumeral joint and attaches to the scapula, humerus, and head of the biceps. It is lined by a thin, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plica Syndrome
Plica syndrome is a condition that occurs when a ''plica'' (a vestigial extension of the protective synovial capsule of usually the knee) becomes irritated, enlarged, or inflamed. Cause This inflammation is typically caused by the plica being caught on the femur, or pinched between the femur and the patella. The most common location of plica tissue is along the medial (inside) side of the knee. The plica can tether the patella to the femur, be located between the femur and patella, or be located along the femoral condyle. If the plica tethers the patella to the femoral condyle, the symptoms may cause it to be mistaken for chondromalacia. The plica themselves are remnants of the fetal stage of development where the knee is divided into three compartments. The plica normally diminish in size during the second trimester of fetal development, as the three compartments develop into the synovial capsule. In adults, they normally exist as sleeves of tissue called synovial folds. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Capsule Of The Humerus
The capsule of the glenohumeral (shoulder) joint is the articular capsule of the shoulder. It completely surrounds the joint. It is attached above to the circumference of the glenoid cavity beyond the glenoidal labrum, and below to the anatomical neck of the humerus, approaching nearer to the articular cartilage above than in the rest of its extent. It is thicker above and below than elsewhere, and is so remarkably loose and lax, that it has no action in keeping the bones in contact, but allows them to be separated from each other more than 2.5 cm, an evident provision for that extreme freedom of movement which is peculiar to this articulation. It is strengthened, above, by the Supraspinatus; below, by the long head of the Triceps brachii; behind, by the tendons of the Infraspinatus and Teres minor; and in front, by the tendon of the Subscapularis. Structure There are usually three openings in the capsule. * One anteriorly, below the coracoid process, establishes a communic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articular Capsule Of The Knee Joint
The articular capsule of the knee joint (commonly referred to as the capsular ligament) is the wide and lax joint capsule of the knee. It is thin in front and at the side, and contains the patella, ligaments, menisci, and bursae of the knee.Platzer (2004), p 206 The capsule consists of an inner synovial membrane, and an outer fibrous membrane separated by fatty deposits anteriorly and posteriorly.Platzer (2004), p 210 Synovial membrane Anteriorly, the reflection of the synovial membrane lies on the femur; located at some distance from the cartilage because of the presence of the suprapatellar bursa. Above, the reflection appears lifted from the bone by underlying periosteal connective tissue. In a standing posture, the suprapatellar bursa is seemingly redundant. It is however also referred to as the ''suprapatellar synovial recess'' as it gradually unfolds as the knee is flexed; to open up completely when the knee is flexed 130 degrees.''Thieme Atlas of Anatomy'', pp 40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlanto-axial Joint
The atlanto-axial joint is a joint in the upper part of the neck between the atlas bone and the axis bone, which are the first and second cervical vertebrae. It is a pivot joint. Structure The atlanto-axial joint is a joint between the atlas bone and the axis bone, which are the first and second cervical vertebrae. It is a pivot joint. There is a pivot articulation between the odontoid process of the axis and the ring formed by the anterior arch and the transverse ligament of the atlas. Lateral and median joints There are three atlanto-axial joints: one median and two lateral: * The median atlanto-axial joint is sometimes considered a triple joint: ** one between the posterior surface of the anterior arch of atlas and the front of the odontoid process ** one between the anterior surface of the ligament and the back of the odontoid process * The lateral atlantoaxial joint involves the lateral mass of atlas and axis. Between the articular processes of the two bones there is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capsule Of Atlantooccipital Articulation
The atlanto-occipital joint (''Capsula articularis atlantooccipitalis'') is an articulation between the atlas bone and the occipital bone. It consists of a pair of condyloid joints. It is a synovial joint. Structure The atlanto-occipital joint is an articulation between the atlas bone and the occipital bone. It consists of a pair of condyloid joints. It is a synovial joint. Ligaments The ligaments connecting the bones are: * Two articular capsules * Posterior atlanto-occipital membrane * Anterior atlanto-occipital membrane Capsule The capsules of the atlantooccipital articulation surround the condyles of the occipital bone, and connect them with the articular processes of the atlas: they are thin and loose. Function The movements permitted in this joint are: * (a) flexion and extension around the mediolateral axis, which give rise to the ordinary forward and backward nodding of the head. * (b) slight lateral motion, lateroflexion, to one or other side around the anteroposter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
