Knee osteoarthritis

Professor Nicola Portinaro explains symptoms, causes, diagnosis and treatment of knee osteoarthritis (arthritis in knee).

What is Knee Osteoarthritis

Knee Osteoarthritis or Arthritis of the Knee joint is a form of inflammation that affects the articular cartilage of the knee.

It can be hereditary or result from past injuries or infection. Arthritis can affect any joint in our body, but it is quite common in knee joints.

This condition affects the bones, the cartilage, and the synovium and progressively makes it difficult to do daily activities such as walking and climbing stairs.

Arthritis eventually erodes the natural cushioning between joints and this process reduces the shock-absorbing benefits of cartilage and synovium. 

Knee Osteoarthritis Causes

Age is the most common cause of osteoarthritis, but other factors can increase the risk of developing this condition such as

  • Altered biomechanics as deviation of the loading forces on the joint
  • Weight, because it puts more pressure on the joints. 
  • Family History (genetics)
  • Gender. Women are more likely than men to develop knee osteoarthritis
  • Injuries. In particular repetitive stress injuries, for example, depending on the job (i.e., professional athletes may be at higher risk of developing this condition)
  • Previous traumas

Knee Osteoarthritis Symptoms

Symptoms may include:

  • pain that is worse in the morning and decreases with rest
  • swelling
  • stiffness in the knee that makes it difficult to straighten the knee
  • a feeling of warmth in the joint
  • sometimes the knee may creak and click or make a grinding noise

Because of the pain, you may feel weaker, and many people notice a decrease in strength of the tight muscles. 

Knee Osteoarthritis Diagnosis

If you are experiencing knee pain, it is advisable to see a doctor who can perform a physical examination and ask you about symptoms and your personal, family, and medical history. 

The doctor will examine the joint, its range of motion and may also ask for diagnostic tests such as:

  • MRI scans 
  • X-rays plain or specific

Other tests, such as blood tests can help to exclude other diseases, such as rheumatoid arthritis.

Knee Osteoarthritis Treatments

The main goal of any Osteoarthritis Treatment is to reduce pain and increase joint mobility. 

Also, treatment options mainly depend on the stage of the condition and how quickly it is progressing.

Non-surgical treatment

To reduce pain, treatment may include:

  • Exercise. Stretching exercises and physical therapy to strengthen the muscles around the knee and increase flexibility in the joints
  • Anti-inflammatory drugs 
  • Diet to diminish weight if necessary in order to reduce stress on the knee joint
  • Injections of corticosteroids that are very powerful anti-inflammatory drugs. 
  • Injections of Hyaluronic acid which is a lubricating fluid normally present in joints
  • Alternative therapies. such as acupuncture, pain-relieving ointments and creams, magnetic pulse therapy or shock waves
  • Use of Assistive devices such as shock-absorbing shoes or braces. Braces can be of two kinds: “unloader” braces that shift weight away from the affected portion of the knee and “support” braces that support the entire knee load.

Surgical Treatment

Surgery may be needed if the cartilage has significantly diminished or even completely disappeared.

The main surgery options are arthroscopy, osteotomy, and arthroplasty.

  • Arthroscopy is performed through small incisions, and the doctor uses a small telescope to see into the joint and remove damaged cartilage, clean the bone surface, and repair tissues
  • Osteotomy. Through this procedure, the doctor will change the shape and the loading angles (knee varus/valgus) of the bones to better align the joint. The doctor can cut and reshape either the tibia (shinbone) or femur (thighbone). This surgery is used when at early-stage osteoarthritis that for example, has damaged just one side of the knee joint. 
  • Joint replacement or arthroplasty, is a surgical procedure in which the orthopedic surgeon partially or totally replaces the joints with artificial parts made from metal or plastic. The doctor will remove the damaged cartilage and bone, and then position the new prosthesis in order to restore the function of your knee.


Recovery and rehabilitation depend on the type of surgery.

The orthopedic surgeon may recommend physical therapy to strengthen muscles around the knee and to restore range of motion.


There are some measures and lifestyles behaviors that can reduce the risk of developing this disease, such as 

  • Maintaining an ideal weight not to put too much pressure on the knees
  • Reducing sugar consumption because high glucose levels can affect the structure and function of cartilage. Diabetes, for example, increases the risk of inflammation and cartilage loss.
  • Exercise regularly in order to have more flexible joints and stronger muscles to support the knees. Even gardening and walking for 20/30 minutes at a time 3 to 5 days a week can help
  • Avoid overuse and reduce the risk of injury. These factors may depend on the sport you practice or on your profession. For example you can diversify activities and caring about taking enough breaks while you’re at work.
  • Undergoing posture tests such as gait analysis and other tests that can help your orthopedic surgeon to determine your bone alignment and correct your posture if needed. 

The experience of Prof. Portinaro

Although Prof Portinaro is mainly a Pediatric Orthopedic Surgeon, he has gained a great deal of experience over the years in performing surgeries such as osteotomy and joint replacement in both arthritic and non-arthritic patients. He is also one of the most qualified surgeons for knee and foot surgery.


Discover How Prof. Portinario Deals With His Patients


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