Diagnosis and treatment of hip and knee osteoarthritis

The most common type of arthritis is osteoarthritis, or age-related cartilage loss

The most common form of arthritis is osteoarthritis. It's caused by cartilage loss within our joints as we age. This article is formatted specifically for patients. It provides easily digestible information on our most evidence-based understanding of osteoarthritis causes, symptoms, and treatments.

Real surgical footage reveals what arthritis looks like up close

Arthritis is a painful condition of human joints that often results from the loss or breakdown of the soft cartilage padding that naturally exists between bones. This video shows footage from an actual knee surgery that beautifully demonstrates the difference between normal cartilage and the degenerative cartilage seen in osteoarthritis.

Anatomy of a healthy knee joint

To understand arthritis, study a normal joint. Where two bones come together, each is lined by a cartilage cap. These bones are linked together by strong ligaments. The inner juncture is lined by a joint capsule (synovial membrane) containing lubricating joint fluid between the two surfaces, allowing for near-frictionless motion.

Arthritis is an umbrella term for various conditions that cause joint pain

Arthritis isn’t one single disease, but rather a range of conditions that all lead back to the same outcome—joint pain. This American Academy of Orthopaedic Surgeons primer is a go-to resource for understanding what arthritis is, the most common types, and various treatment options depending on the underlying cause.

Arthritis explained, with Dr. Nick Golinvaux

Arthritis, a condition affecting millions globally, is more than just joint pain—it’s a breakdown of cartilage that cushions bones, leading to stiffness, swelling, and discomfort. While often associated with aging, arthritis can affect people of all ages, especially after injuries. Though there’s no cure yet, treatments range from medication and physical therapy to surgical interventions like joint replacements.

Kangaroos evolved exceptionally thick knee cartilage to absorb shock

There is significant conflict in the medical field regarding chronic arthritis. Some advocate for keeping the joint as active as possible while others argue progressive overuse leads to worsening arthritis. To settle the score, scientists have looked outside the human population, discovering kangaroos rarely suffer from arthritis in their knees.

There is no cure for the general condition of arthritis

While there are innumerable conditions ultimately leading to the joint pain we collectively term "arthritis," one common pathway is progressive inflammation and joint damage many years after an injury.

Rheumatoid arthritis occurs when the immune system attacks cells within joints

Rheumatoid arthritis is a specific type of arthritis that occurs when the body's immune system attacks normal cells within the connective tissues of the joint and degrades them. This sets off a painful cycle of inflammation and joint destruction that often requires lifelong medication to control.

Five advancements in arthritis research

It is estimated that nearly 350 million people worldwide are currently suffering from arthritis. This resource explores five of the most promising recent advancements in arthritis research as scientists work towards improved treatments and continue the search for a cure.

Breaking down the knee's anatomy

The human knee is a remarkably complex structure carrying the full weight of the body throughout a person’s life while allowing a number of complex twists, flexes, and extensions. It's also one of the body's biggest weaknesses—the location of chronic pain and replacement surgeries for millions of Americans.

Yoga can be beneficial for aging practitioners

Studies suggest that yoga can help alleviate several diseases associated with aging by lowering blood pressure, reducing blood fat levels, and combating obesity. It has also been shown to increase telomerase activity, which helps slow cell aging.

The collapse of gas bubbles in the joint synovial fluid causes 'cracking' knuckles

The human population can be divided into two categories: those who crack their knuckles and those who don't. Do you know the technical term for this phenomenon is "tribonucleation?" What actually happens inside a knuckle when it pops? This visual explainer breaks down finger joint popping in real time.

Inflammaging is chronic low-level inflammation as we age, and it may be a key disease driver

The term refers to the idea that largely invisible but consistent low-level inflammation as humans age fuels chronic diseases and cellular aging. Inflammaging, this article says, is due to lifestyle factors like poor sleep, low levels of activity, and poor diet, acting in concert to cause cellular damage and trigger inflammation.

Stroke risk doubles each decade after age 55

While age is the greatest risk factor, genetics, diet, and overall health play a prominent role in determining individual stroke risk. Prevention focuses heavily on modifiable risk factors. High blood pressure is the single most important controllable risk factor, contributing to both types of stroke.

Photodynamic therapy is one current treatment for age-related macular degeneration

This laser-based treatment is used on advanced "wet" age-related macular degeneration patients, but it's now used less often than in the past because there are newer injection-based drugs to decrease abnormal blood vessel growth.

How neurodegeneration happens, the underlying disease process of dementia

Dementia symptoms may vary between individuals, and may include mood changes, difficulty walking, speaking, and memory problems. It can progress over many years, occurring due to progressive damage to nerve cells in the brain. This degradation may happen for myriad reasons, and its triggers are under investigation.

Women experience heightened bone loss after menopause

Both women and men begin to lose some bone density after age 35, on average, but for the first decade after menopause women lose bone more rapidly due to the significantly decreased levels of estrogen, putting women at heightened risk of osteoporosis and related bone fractures.

What is cardiovascular disease?

Cardiovascular diseases are a range of related health conditions that develop in the heart and blood vessels. This article and related infographics detail cardiovascular disease types and treatments.

Explore why swimmer's ear will not go away on its own

This infection is typically treated with ear drops to reduce inflammation and fight the bacteria or fungus that led to the issue. But without treatment, complications can arise, including a deep tissue infection, bone or cartilage damage, or—very rarely—spreading beyond the ear into the skull bones and surrounding areas.

What is glacial archaeology?

Melting glaciers continue to reveal archaeological and anthropological evidence previously hidden by solid ice. This article details the newer archaeological field, which was popularized after the 1991 discovery of Ötzi the Iceman. A German couple came across Ötzi as they hiked the Ötzal Alps near the Italy-Austria border. Ötzi was initially believed to be the corpse of an unlucky mountaineer, but further study revealed he had been dead for about 5,300 years.

Overuse of opioids can lead to hypersensitivity to pain

Opioid misuse can lead opioid-induced hyperalgesia, where the body becomes increasingly sensitive to pain. The body produces its own opioids as a way to temporarily block pain signals. When met with external opioid use, the body ratchets up pain sensitivity to ensure it senses the pain necessary to trigger its own response.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Type 1.5 diabetes is typically found in adulthood

Clinically referred to as latent autoimmune diabetes in adults, or LADA, this condition is often diagnosed as Type 2 diabetes. However, it’s an autoimmune disease that eventually requires insulin, just like Type 1 diabetes. Misdiagnosis can result in uncontrolled high blood sugar and a slew of other serious health issues.

Bone marrow transplants were the first successful type of stem cell therapies

Bone marrow contains two types of stem cells: Skeletal (develop into bone, cartilage, and more) and hematopoietic, which create new blood cells. The latter are critical in bone marrow transplants, and give the recipient the ability to create healthy blood cells to fight diseases like leukemia.

See worldwide hearing loss by age group and country

This 2023 data from the Institute for Health Metrics and Evaluation shows the estimated number of people with complete hearing loss in different age groups per 100,000 people in the population. Individuals aged 70 or older make up the largest group with this type of hearing deficit.

The 100 best hip-hop albums of all time

Although it still sounds youthful, hip-hop reached middle age in 2023, reaching its 50th anniversary. This Pitchfork list of the genre's 100 best albums spans the entire history of the genre. Despite a few controversial picks, it's still worth a read, if only to dig back into some classics.

About 2,000 US babies are born annually without some portion of their limbs, potentially leading to a lifetime of pricey prosthetics.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Animal phobias are likely the most common type of phobias, followed by an extreme fear of heights.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

See the evolution of Ebola vaccine and treatment development.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

See images of medical cases of firework injuries shared on this 'Instagram for doctors.' (Warning: Graphic content)

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Poison ivy's characteristic rash is caused by an allergic response to an oily compound in the plant called urushiol.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Frank Lloyd Wright's houses are historically hard to sell because they're old, subject to local landmark commissions, and often unfashionable

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by over 1.5 million Muslims.

Art theft is the third-largest source of criminal revenues worldwide, thanks in part to the subjective nature of valuing a work of art.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

Dozens of S&P 500 stocks, including Coca-Cola and Walmart—known as the dividend aristocrats—have increased dividends every year for 25 years

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

The Russia-Ukraine conflict is the largest ground war in Europe since World War II in terms of casualties, forces mobilized, and displacement of civilians.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

'Saturday Night Fever,' the 1977 film that introduced disco to the mainstream, was based on a fabricated magazine story.