This fluid-filled cyst occurs behind the knee and can be caused by arthritis or a cartilage tear. Treating the cause usually provides relief.
Disease
Yips
Learn about what causes these involuntary wrist spasms that often frustrate golfers.
Disease
Calciphylaxis
Learn more about this uncommon condition that affects small blood vessels and skin tissues, causing painful skin ulcers.
Disease
Hepatopulmonary syndrome
This lung condition causes low oxygen levels and shortness of breath in people who have advanced liver disease.
Disease
Auditory processing disorder (APD)
This type of hearing loss involves the brain. Learn about ways that can help people with the condition hear better.
Disease
Benign adrenal tumors
Most of these tumors need no treatment, but some do. Learn about diagnosis and treatment options.
Disease
Sleep disorders
Common types include insomnia, sleep apnea, restless legs syndrome and narcolepsy. Other types include nightmare disorder and sleep terrors.
Disease
Anal fistula
An infected anal gland can sometimes cause a tunnel to develop between the skin and the anus. Learn about symptoms and diagnosis for this painful, but treatable, condition.
Disease
Vasovagal syncope
Learn about what causes a brief loss of consciousness and when to see a healthcare professional if this happens to you.
Disease
Fibromyalgia
This condition affects the way the brain processes pain signals. It can cause widespread pain, fatigue and other symptoms. Learn what treatments can help.
Disease
Thrombocytopenia (low platelet count)
Problems with how blood clots can lead to excessive bleeding or blood clotting. Learn about the risks and treatments for a low blood platelet count.
Disease
Inflammatory bowel disease (IBD)
Long-lasting diarrhea and belly pain could be caused by inflammatory bowel disease, also called IBD. Learn about IBD causes, diagnosis and treatment.