This pain at the front of the knee is more common in people who run and who play sports that involve running and jumping.
Disease
Bone spurs
Joint damage due to osteoarthritis is the most common cause of these bony growths.
Disease
Amyotrophic lateral sclerosis (ALS)
This progressive nervous system disease, also known as Lou Gehrig's disease, destroys nerve cells.
Disease
Pediatric brain tumors
Pediatric brain tumors include medulloblastoma, glioma, embryonal tumor, germ cell brain tumor, spinal cord tumor, craniopharyngioma and pineoblastoma.
Disease
Neuromyelitis optica
Understand more about this condition that affects the spinal cord and eye nerves and is sometimes mistaken for multiple sclerosis.
Disease
Radiation sickness
Read about what happens when someone is exposed to high doses of radiation, and what you can do to prevent such exposure in an emergency.
Disease
Pulmonary hypertension
This lung condition makes the heart work harder and become weak. Changes in genes and some medicines and diseases can cause it. Learn more.
Disease
Metatarsalgia
With this condition, the ball of the foot becomes painful and irritated. Learn about the causes, treatments and prevention of this injury.
Disease
Multiple endocrine neoplasia, type 2 (MEN 2)
Learn about this rare disorder that causes tumors and overproduction of hormones.
Disease
Listeria infection
This illness is caused by bacteria that spreads in food. It can be very serious for some people. Learn about symptoms, treatment and tips to prevent it.
Disease
Immune thrombocytopenia (ITP)
Caused by low levels of platelets, symptoms may include purple bruises called purpura, as well as tiny reddish-purple dots that look like a rash.
Disease
C. difficile infection
Learn more about this diarrhea-causing infection that often occurs after antibiotic use. Many, but not all, people who get it are in health care facilities.