Knee Arthritis (Osteoarthritis) (Also known as Knee Osteoarthritis, Osteoarthritis of the Knee, Arthritis of the Knee, Degeneration of the Knee)

N.B. The term knee arthritis will be used in this document to describe the condition known as knee osteoarthritis.

What is knee arthritis? 

Knee arthritis is a condition characterized by a degenerative process whereby there is gradual eroding of the surfaces of the knee joint with subsequent inflammation. This may occur following a specific injury or due to repetitive forces going through the knee beyond what it can withstand over a period of time. In a normal knee, joint surfaces are smooth and there is cartilage between the bone ends which allows for efficient shock absorption. 

(figure 1)

                                Figure.1                                                   Figure. 2

When the knee is damaged or overloaded, particularly with excessive weight-bearing or twisting force, degeneration of the cartilage occurs which reduces the knee's shock absorption capacity. As the condition progresses there is eventual wearing down of the bone ends so that the surfaces are no longer smooth (figure 2) and may have small bony processes called osteophytes. This condition is known as knee arthritis. Arthritis of the knee usually occurs after the age of 45 years. It is more common in those patients who are overweight or have a past history of injury or trauma to the knee. Signs and symptoms of knee arthritis Patients with this condition usually experience symptoms that develop gradually over time. In patients with minor cases of knee arthritis, little or no symptoms may be present. As the condition progresses, there may be increasing knee pain with weight bearing activity and joint stiffness - particularly after rest and first thing in the morning. Swelling, decreased flexibility (i.e. an inability to fully straighten or bend the knee), severe joint pain, pain at night and grinding sensation during certain movements may also be experienced. Symptoms can sometimes fluctuate from month to month with patients reporting an increase in symptoms with colder weather. In more severe cases, muscle wasting (especially of the quadriceps), a visible deformity of the knee joint, and a limp may also be present.

Diagnosis of knee arthritis

A thorough subjective and objective examination from a physiotherapist may be sufficient to diagnose knee arthritis. An X-ray is usually required to confirm diagnosis. Sometimes an MRI may also be indicated.

Treatment for knee arthritis

Whilst little can be done to reverse the degenerative changes to the knee associated with this condition, patients can generally remain active by modifying their activities appropriately. The primary goal of treatment is to remain as active as possible without aggravating symptoms in order to maintain strength and mobility and to avoid deterioration. Treatment should be directed at improving knee range of movement, reducing swelling and pain, and restoring normal function. Most minor to moderate cases of knee arthritis can be managed with an appropriate physiotherapy program so the patient can remain relatively symptom free and active. The success rate of this program is largely dictated by patient compliance. One of the key components is that patients rest from aggravating activity and balance their weight bearing activity with periods of rest (e.g. sitting or lying) to keep symptoms to a minimum. This prevents further damage and deterioration and allows the body to clear any swelling or inflammation. Continuing to participate in painful weight bearing activity is likely to lead to a poor outcome. It is important, however, to keep as active as possible by choosing activities that do not increase symptoms. Better activities for knee arthritis include swimming, hydrotherapy or bike riding .It is very important that patients with this condition perform regular movement and strength exercises to prevent stiffness and weakness from developing and to ensure the knee is functioning correctly. Pain relief and anti-inflammatory medication may also assist in managing the symptoms associated with arthritis of the knee.

Physiotherapy for knee arthritis

Physiotherapy treatment for patients with this condition is vital to hasten the healing process and ensure an optimal outcome.

Treatment may comprise:

• Soft tissue massage
• Electrotherapy (e.g. Ultrasound,SWD,IFT)
• Taping
• The use of a knee brace or compression bandage
•  Mobilization
• Ice or heat treatment
• Exercises to improve strength, flexibility and balance
• Hydrotherapy
• The use of walker or other walking aids
• Activity and lifestyle modification advice
• Biomechanical correction
• Anti-inflammatory and supplement advice (e.g. glucosamine and chondroitin)  
• Weight loss advice where appropriate (As obesity is associated with the onset of osteoarthritis, weight loss, if needed, can have a significant effect on slowing the disease progression)

Other intervention for knee arthritis

In more advanced cases of knee arthritis, where symptoms are severe, patients may require surgical intervention. This may involve a knee arthroscope or partial or complete joint replacement surgery. The treating physiotherapist or doctor can advise if this may be required and will refer to an orthopaedic specialist for an assessment and opinion.