Transient synovitis of  hip (also called toxic synovitis; see below for more synonyms) is a self-limiting condition in which there is an inflammation of the inner lining (the synovium) of the capsule of the hip joint. The term irritable hip refers to the syndrome of acute hip pain, joint stiffness, limp or non-weightbearing, indicative of an underlying condition such as transient synovitis or orthopedic infections (like septic arthritis or osteomyelitis). In everyday clinical practice however, irritable hip is commonly used as a synonym for transient synovitis. It should not be confused with sciatica, a condition describing hip and lower back pain much more common to adults than transient synovitis but with similar signs and symptoms. Transient synovitis usually affects children between three and ten years old (but it has been reported in a 3-month-old infant and in some adults). It is the most common cause of sudden hip pain and limp in young children. Boys are affected two to four times as often as girls. The exact cause is unknown. A recent viral infection (most commonly an upper respiratory tract infection) or a trauma have been postulated as precipitating events, although these are reported only in 30% and 5% of cases, respectively.Transient synovitis is a diagnosis of exclusion. The diagnosis can be made in the typical setting of pain or limp in a young child who is not generally unwell and has no recent trauma. There is a limited range of motion of the hip joint.
Examples of sociocusis-related stimuli are the continuous noises from traffic, home appliances, music, television, and radio. The accumulated exposure to these noises over many years can lead to a condition similar to pure presbycusis. Nosocusis
Nosocusis factors are those that can cause hearing loss, which are not noise-based and separate from pure presbycusis. They may include:
Ototoxic drugs: Ingestion of ototoxic drugs like aspirin may hasten the process of presbycusis. vascular degeneration
Atherosclerosis: May diminish vascularity of the cochlea, thereby reducing its oxygen supply. Dietary habits: Increased intake of saturated fat may accelerate atherosclerotic changes in old age. Smoking: Is postulated to accentuate atherosclerotic changes in blood vessels aggravating presbycusis. Diabetes: May cause vasculitis and endothelial proliferation in the blood vessels of the cochlea, thereby reducing its blood supply. Hypertension: causes potent vascular changes, like reduction in blood supply to the cochlea, thereby aggravating presbycusis.However, a recent study found that diabetes, atherosclerosis and hypertension had no correlation to presbycusis, suggesting that these are nosocusis (acquired hearing loss) factors, not intrinsic factors. Pathophysiology
Examples of microscopic changes seen in this condition are hair cell degeneration of the cochlea and giant stereociliary degeneration. There are four pathological phenotypes of presbycusis:

Sensory: characterised by degeneration of the organ of Corti, the sensory organ for hearing. Located within the scala media, it contains hair cells with stereocilia, which extend to the tectorial membrane. The organs outer hair cells play a significant role in the amplification of sound and is extremely sensitive to external and internal factors.