Where skeletal muscle is voluntary, cardiac muscle is autorhythmic (beats involuntarily; generates its own action potentials). 3. Smooth muscle: refers to the muscles that are controlled involuntarily by the brain, like those attached to the base of hair follicles or in the walls of the gastro-intestinal tract.The muscle has a single nucleus in the middle of the cell. Skeletal and cardiac muscle are types of straited muscle.here skeletal muscle is voluntary, cardiac muscle is autorhythmic (beats involuntarily; generates its own action potentials). 3. Smooth muscle: refers to the muscles that are controlled involuntarily by the brain, like those attached to the base of hair follicles or in the walls of the gastro-intestinal tract.
When this results in irritation or damage to the adjacent nerves at the T4 level and the patient experiences diffuse arm pain, pins and needles or numbness in the upper arm the condition is known as T4 syndrome. Causes of T4 syndrome. T4 syndrome typically occurs due to injury to the facet joints or disc at T4 which then affects the nerve root at that level. Injury to these structures can occur during excessive bending, lifting, arching, or twisting movements or due to poor posture.
A total T4 test measures the T4 that has bonded to protein and the free T4. A free T4 test measures only the free T4 in your blood. Your doctor may order a T4 test if a thyroid-stimulating hormone (TSH) test has come back with abnormal results. A T4 test will help your doctor determine what is wrong with your thyroid. Some thyroid disorders include: hyperthyroidism (overactive thyroid)