On this page

Basics

• Summary
• Start Here
• Symptoms
• Diagnosis and Tests
• Treatments and Therapies

Learn More

• Living With
• Specifics

See, Play and Learn

• Images
• Test Your Knowledge

Research

• Clinical Trials
• Journal Articles

Resources

• Find an Expert

For You

• Children
• Teenagers
• Patient Handouts

Summary

Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt or diseased, you have knee problems. Knee problems can cause pain and difficulty walking.

Knee problems are very common, and they occur in people of all ages. Knee problems can interfere with many things, from participation in sports to simply getting up from a chair and walking. This can have a big impact on your life.

The most common disease affecting the knee is osteoarthritis. The cartilage in the knee gradually wears away, causing pain and swelling.

Injuries to ligaments and tendons also cause knee problems. A common injury is to the anterior cruciate ligament (ACL). You usually injure your ACL by a sudden twisting motion. ACL and other knee injuries are common sports injuries.

Treatment of knee problems depends on the cause. In some cases your doctor may recommend knee replacement.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases

Start Here

• Common Knee Injuries (American Academy of Orthopaedic Surgeons)
• Knee Problems (American Academy of Family Physicians) Also in Spanish

Symptoms

• Iliotibial Band Syndrome (For Parents) (Nemours Foundation) Also in Spanish

Diagnosis and Tests

• Direct Arthrography (American College of Radiology; Radiological Society of North America) Also in Spanish
• Knee MRI (American College of Radiology; Radiological Society of North America) Also in Spanish
• Knee Problems (American Academy of Family Physicians) Also in Spanish
• X-Ray Exam: Knee (For Parents) (Nemours Foundation) Also in Spanish

Treatments and Therapies

• ACL Injury: Diagnosis and Treatment (Mayo Foundation for Medical Education and Research)
• Iliotibial Band Syndrome (For Parents) (Nemours Foundation) Also in Spanish
• Knee Arthroscopy (American Academy of Orthopaedic Surgeons)
• Knee Replacement: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

Living With

• Knee Bracing: What Works? (American Academy of Family Physicians) Also in Spanish
• Knee Rehabilitation Exercises (American Academy of Orthopaedic Surgeons)
• Mobility Aids: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

Specifics

• ACL Injury (American Academy of Family Physicians)
• Baker Cyst (Mayo Foundation for Medical Education and Research)
• Osteochondritis Dissecans (American Academy of Family Physicians) Also in Spanish
• Patellar Tendinitis (Mayo Foundation for Medical Education and Research) Also in Spanish
• Patellofemoral Pain Syndrome (American Academy of Family Physicians) Also in Spanish
• Pigmented Villonodular Synovitis (PVNS) (American Academy of Family Physicians) Also in Spanish
• Posterior Cruciate Ligament (PCL) Injuries (American Academy of Orthopaedic Surgeons)
• Swollen Knee (Mayo Foundation for Medical Education and Research) Also in Spanish

Images

• Anterior cruciate ligament repair - series (Medical Encyclopedia) Also in Spanish
• Knee arthroscopy - series (Medical Encyclopedia) Also in Spanish

Test Your Knowledge

• Knee Pain Myths & Facts Quiz (Medical Encyclopedia) Also in Spanish

Clinical Trials

• ClinicalTrials.gov: Anterior Cruciate Ligament (ACL) Injuries (National Institutes of Health)
• ClinicalTrials.gov: Anterior Cruciate Ligament Reconstruction (National Institutes of Health)
• ClinicalTrials.gov: Articular Cartilage Disorders (National Institutes of Health)
• ClinicalTrials.gov: Knee Injuries (National Institutes of Health)
• ClinicalTrials.gov: Menisci, Tibial (National Institutes of Health)
• ClinicalTrials.gov: Patella Disorders (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Effects of 2 different rehabilitation programs on jumping performance after ACL...
• Article: Microfracture Versus Arthroscopic Debridement for the Treatment of Symptomatic Cartilage Lesions...
• Article: Application of Teach-back health education combined with continuity care in patients...
• Knee Injuries and Disorders -- see more articles

Find an Expert

• Find a Doctor in American Association of Hip and Knee Surgeons (American Association of Hip and Knee Surgeons)
• National Institute of Arthritis and Musculoskeletal and Skin Diseases Also in Spanish

Children

• Osgood-Schlatter Disease (For Parents) (Nemours Foundation)
• Osteochondritis Dissecans (For Parents) (Nemours Foundation) Also in Spanish

Teenagers

• Anterior Cruciate Ligament (ACL) Tears (Nemours Foundation) Also in Spanish
• Jumper's Knee (Nemours Foundation) Also in Spanish
• Knee Injuries (Nemours Foundation) Also in Spanish
• Medial Collateral Ligament (MCL) Injuries (Nemours Foundation) Also in Spanish
• Meniscus Tears (Nemours Foundation)
• Osgood-Schlatter Disease (Nemours Foundation) Also in Spanish
• Patellofemoral Pain Syndrome (Runner's Knee) (Nemours Foundation) Also in Spanish

Patient Handouts

• ACL reconstruction (Medical Encyclopedia) Also in Spanish
• Anterior crucate ligament (ACL) injury (Medical Encyclopedia) Also in Spanish
• Anterior cruciate ligament (ACL) injury -- aftercare (Medical Encyclopedia) Also in Spanish
• Anterior knee pain (Medical Encyclopedia) Also in Spanish
• Baker cyst (Medical Encyclopedia) Also in Spanish
• Broken kneecap - aftercare (Medical Encyclopedia) Also in Spanish
• Collateral ligament (CL) injury -- aftercare (Medical Encyclopedia) Also in Spanish
• Getting your home ready - knee or hip surgery (Medical Encyclopedia) Also in Spanish
• Knee arthroscopy (Medical Encyclopedia) Also in Spanish
• Knee MRI scan (Medical Encyclopedia) Also in Spanish
• Knee pain (Medical Encyclopedia) Also in Spanish
• Meniscus tears - aftercare (Medical Encyclopedia) Also in Spanish
• Osgood-Schlatter disease (Medical Encyclopedia) Also in Spanish