Osteoarthritis of the Knee

What is Knee Osteoarthritis?

Osteoarthritis, the most common type of arthritis, is caused primarily by age-related wear-and-tear that involves the deterioration of the smooth outer covering of bone, known as cartilage.

The knee is the largest joint in the body and bears most of our body’s weight. Due to the natural wear-and-tear that comes with constant lifting and moving, the knee is frequently affected by arthritis.

How Common is Knee Osteoarthritis?

More than one in four Americans suffer from bone or joint health problems, making it the leading cause of physical disability in the United States. Nearly 50 percent of American adults develop knee osteoarthritis over their lifetime.

  • 14 million American currently have symptomatic knee osteoarthritis
  • Nearly 2 million people under the age of 45 experience the condition
  • About 13 percent of women and 10 percent of men age 60 and older have symptomatic knee osteoarthritis

More than half of all individuals with diagnosed symptomatic knee osteoarthritis have had sufficient progression of osteoarthritis that would make them eligible for knee replacement surgery.

What Causes Knee Osteoarthritis?

The following factors play a role in the development of knee osteoarthritis.

  • Age: The risk of developing knee osteoarthritis increases with each decade of life with the highest incidence being between age 55 and 64 years old, although increased sports participation at a younger age has contributed to rising numbers of knee problems earlier in life.
  • Genetics: Those who have a family member with osteoarthritis are more likely to develop the condition.
  • Anatomical variant: How a body part is formed in an individual can lead to increased cartilage deterioration.
  • Obesity: The stress of carrying extra weight on joints exacerbates wear and tear. For every pound you lose, 4 to 7 pounds of pressure is taken off the knee joint.
  • Gender: Women are more likely to develop osteoarthritis than men.
  • Trauma: An injury can lead to post-traumatic arthritis, a form of osteoarthritis spurred by injury.

What Are Symptoms of Knee Osteoarthritis?

The following are common symptoms of knee osteoarthritis.

  • Pain with activity
  • Limitations in range of motion
  • Stiffness
  • Swelling
  • Tenderness
  • Grinding or crunching sensation

Arthritic knees can come in pairs, but it’s more common to develop osteoarthritis in one knee, as people may favor one leg over the other while walking or running.

How is Knee Osteoarthritis Diagnosed?

The diagnosis of knee osteoarthritis begins with a physical examination and x-rays. During the physical exam, the doctor examines the knee joint for swelling, range of motion, muscle strength, tenderness and gait problems (difficulty walking).

The X-rays may show narrowing joint space, malalignment, bone changes, and/or bone spurs – all signs of an arthritic knee. Other tests may be needed to determine the cause of knee pain. These may include an MRI, CT scan, or bone scans.

How is Knee Osteoarthritis Treated?

Knee osteoarthritis can be managed with many different types of treatments. Depending on the severity of the diagnosis, non-surgical or surgical treatment options may be recommended.

Non-surgical Knee Osteoarthritis Treatment Options

The goals of non-surgical osteoarthritis treatment are to relieve pain and restore function. The following methods and pain management strategies can help alleviate or manage knee pain and are often recommended before surgery.

  • Activity Modification: Switching to lower-impact physical activities can help reduce pain.
  • Medications: Anti-inflammatory medications (aspirin or ibuprofen)
  • Losing weight: Weight loss can lessen pain and decrease the risk of osteoarthritis.
  • Aerobic and strength training exercises: These exercises are directed at improving strength and wellness around the joint while avoiding further injury.
  • Topical analgesics
  • Knee braces: Over-the-counter or custom braces can help with knee pain.
  • Cortisone injections: Injections of cortisone help decrease inflammation in the knee joint. Relief typically lasts about three months. Patients can receive repeat injections after the first injection wears off, but each injection may be less effective than the previous. Other injection options include viscosupplementation (gel shots), stem cell injections and platelet-rich plasma.

Surgical Treatment Options for Knee Osteoarthritis

When non-surgical treatments don’t relieve knee osteoarthritis symptoms, the following surgical options may be recommended.

  • Full or partial knee replacement (arthroplasty): Removing parts of the bones and creating an artificial joint with metal or plastic components.
  • Arthroscopy: Involves smaller incisions and uses tiny cameras and small instruments to repair defects in the knee that are contributing to wear and tear.
  • Osteotomy: Realigning the tibia and femur to take pressure off the knee joint.
  • Joint reconstruction: Removing the worn joint surface and replacing it with your own soft tissue or with an implant.

Expert Osteoarthritis Care at Brigham and Women’s Hospital

Our world-renowned Brigham and Women’s Hospital Orthopaedic & Arthritis Center team is dedicated to providing the most advanced care for all bone and joint conditions to reduce pain, increase mobility and improve quality of life for our patients.

Our specialists in orthopaedic surgery, physiatry, rheumatology and rehabilitation, work together with dedicated nurses, physician assistants and other professionals, to provide state-of-the-art evaluation and treatment for thousands of patients each year. When it’s time to consider knee replacement surgery, our expert team will work with you to determine the best surgical approach for you.

Schedule an Appointment

To schedule an appointment with one of our bone and joint specialists, please call 800-294-9999, or fill out an online appointment request form.

Refer a Patient

We are dedicated to working with our referring physicians. If you would like to refer a patient with knee osteoarthritis, please call 1-800-MD-TO-BWH (1-800-638-6294) or see our list of referral options.

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