Degeneration is deterioration in the medical sense. Generally, it is the change from a higher to a lower form. More specifically, it is the change of tissue to a lower or less functionally active form.
Wilson's disease is a genetic disorder characterized by the excess build-up of copper in the body. Symptoms are typically related to the brain and liver. Liver-related symptoms include vomiting, weakness, fluid build-up in the abdomen, swelling of the legs, yellowish skin, and itchiness. Brain-related symptoms include tremors, muscle stiffness, trouble in speaking, personality changes, anxiety, and psychosis.
Edema (AmE), also spelled oedema (BrE), and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin that feels tight, the area may feel heavy, and joint stiffness. Other symptoms depend on the underlying cause.
An intervertebral disc lies between adjacent vertebrae in the vertebral column. Each disc forms a fibrocartilaginous joint, to allow slight movement of the vertebrae, to act as a ligament to hold the vertebrae together, and to function as a shock absorber for the spine.
Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the gangrene is caused by an infectious agent, it may present with a fever or sepsis.
A blister is a small pocket of body fluid within the upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid, either serum or plasma. However, blisters can be filled with blood or with pus.
Myxedema is a term used synonymously with severe hypothyroidism. However, the term is also used to describe a dermatological change that can occur in hypothyroidism and (rare) paradoxical cases of hyperthyroidism. In this latter sense, myxedema refers to deposition of mucopolysaccharides in the dermis, which results in swelling of the affected area. One manifestation of myxedema occurring in the lower limb is pretibial myxedema, a hallmark of Graves disease, an autoimmune form of hyperthyroidism. Myxedema can also occur in Hashimoto thyroiditis and other long-standing forms of hypothyroidism.
Diverticulosis is the condition of having multiple pouches (diverticula) in the colon that are not inflamed. These are outpockets of the colonic mucosa and submucosa through weaknesses of muscle layers in the colon wall. Diverticula do not cause symptoms in most people. Diverticular disease occurs when diverticula become clinically inflamed, a condition known as diverticulitis.
Osteophytes are exostoses that form along joint margins. They should not be confused with enthesophytes, which are bony projections that form at the attachment of a tendon or ligament. Osteophytes are not always distinguished from exostoses in any definite way, although in many cases there are a number of differences. Osteophytes are typically intra-articular.
Macular degeneration, also known as age-related macular degeneration, is a medical condition which may result in blurred or no vision in the center of the visual field. Early on there are often no symptoms. Over time, however, some people experience a gradual worsening of vision that may affect one or both eyes. While it does not result in complete blindness, loss of central vision can make it hard to recognize faces, drive, read, or perform other activities of daily life. Visual hallucinations may also occur.
Degenerative disc disease (DDD) is a medical condition typically brought on by the normal aging process in which there are anatomic changes and possibly a loss of function of one or more intervertebral discs of the spine. DDD can take place with or without symptoms, but is typically identified once symptoms arise. The root cause is thought to be loss of soluble proteins within the fluid contained in the disc with resultant reduction of the oncotic pressure, which in turn causes loss of fluid volume. Normal downward forces cause the affected disc to lose height, and the distance between vertebrae is reduced. The anulus fibrosus, the tough outer layers of a disc, also weakens. This loss of height causes laxity of the longitudinal ligaments, which may allow anterior, posterior, or lateral shifting of the vertebral bodies, causing facet joint malalignment and arthritis; scoliosis; cervical hyperlordosis; thoracic hyperkyphosis; lumbar hyperlordosis; narrowing of the space available for the spinal tract within the vertebra ; or narrowing of the space through which a spinal nerve exits with resultant inflammation and impingement of a spinal nerve, causing a radiculopathy.
Caseous necrosis or caseous degeneration is a unique form of cell death in which the tissue maintains a cheese-like appearance. Unlike with coagulative necrosis, tissue structure is destroyed. Caseous necrosis is enclosed within a granuloma. Caseous necrosis is most notably associated with tuberculoma. The dead tissue appears as a soft and white proteinaceous dead cell mass.
Pneumonitis describes general inflammation of lung tissue. Possible causative agents include radiation therapy of the chest, exposure to medications used during chemo-therapy, the inhalation of debris, aspiration, herbicides or fluorocarbons and some systemic diseases. If unresolved, continued inflammation can result in irreparable damage such as pulmonary fibrosis.
Corticobasal degeneration (CBD) is a rare neurodegenerative disease involving the cerebral cortex and the basal ganglia. CBD symptoms typically begin in people from 50 to 70 years of age, and typical survival before death is eight years. It is characterized by marked disorders in movement and cognition, and is classified as one of the Parkinson plus syndromes. Diagnosis is difficult, as symptoms are often similar to those of other disorders, such as Parkinson's disease, progressive supranuclear palsy, and dementia with Lewy bodies, and a definitive diagnosis of CBD can only be made upon neuropathologic examination.
Bradypnea is abnormally slow breathing. The respiratory rate at which bradypnea is diagnosed depends on the age of the person, with the limit higher during childhood.
Stargardt disease is the most common inherited single-gene retinal disease. In terms of the first description of the disease, it follows an autosomal recessive inheritance pattern, which has been later linked to bi-allelic ABCA4 gene variants (STGD1). However, there are Stargardt-like diseases with mimicking phenotypes that are referred to as STGD3 and STGD4, and have a autosomal dominant inheritance due to defects with ELOVL4 or PROM1 genes, respectively. It is characterized by macular degeneration that begins in childhood, adolescence or adulthood, resulting in progressive loss of vision.
Progressive muscular atrophy (PMA), also called Duchenne–Aran disease and Duchenne–Aran muscular atrophy, is a disorder characterised by the degeneration of lower motor neurons, resulting in generalised, progressive loss of muscle function.
A spinal disc herniation is an injury to the intervertebral disc between two spinal vertebrae, usually caused by excessive strain or trauma to the spine. It may result in back pain, pain or sensation in different parts of the body, and physical disability. The most conclusive diagnostic tool for disc herniation is MRI, and treatment may range from painkillers to surgery. Protection from disc herniation is best provided by core strength and an awareness of body mechanics including good posture.
Hereditary motor and sensory neuropathies (HMSN) is a name sometimes given to a group of different neuropathies which are all characterized by their impact upon both afferent and efferent neural communication. HMSN are characterised by atypical neural development and degradation of neural tissue. The two common forms of HMSN are either hypertrophic demyelinated nerves or complete atrophy of neural tissue. Hypertrophic condition causes neural stiffness and a demyelination of nerves in the peripheral nervous system, and atrophy causes the breakdown of axons and neural cell bodies. In these disorders, a patient experiences progressive muscle atrophy and sensory neuropathy of the extremities.
Central nervous system diseases or central nervous system disorders are a group of neurological disorders that affect the structure or function of the brain or spinal cord, which collectively form the central nervous system (CNS). These disorders may be caused by such things as infection, injury, blood clots, age related degeneration, cancer, autoimmune disfunction, and birth defects. The symptoms vary widely, as do the treatments.
Degenerative lumbosacral stenosis (DLSS), also known as cauda equina syndrome, is a pathologic degeneration in the lumbosacral disk in dogs; affecting the articulation, nerve progression, tissue and joint connections of the disk. This degeneration causes compressions in soft tissues and nerve root locations in the ultimate caudal area of the medulla, causing neuropathic pain in the lumbar vertebrae.
Dorland's Illustrated Medical Dictionary (Twenty-sixth Edition) ( ISBN 0-7216-1645-3)