Knee osteoarthritis — or gonarthrosis — is degeneration of the knee joint, which usually becomes clinically apparent in older patients (generally over 60). Gonarthrosis is more common in women and is characterised by progressive wear of the articular cartilage, which causes pain that intensifies over time.
Written and medically reviewed by Dr. Ion Bogdan Codorean, senior orthopaedics-traumatology physician. Updated: August 15, 2026.
Knee osteoarthritis (or gonarthrosis) is degeneration of the knee joint. Osteoarthritis affects all joints and is characterised pathologically by progressive degenerative damage to the hyaline articular cartilage, involving the subchondral bone, the synovium and the soft tissues around the joint, and clinically by pain, deformity and restricted movement in the affected joints.
The main symptom of gonarthrosis is knee pain. The pain usually appears in the morning or after a longer period of inactivity. It becomes chronic, though not constant in intensity, flaring up suddenly when the joint is overloaded — for example when going up or down stairs. The pain also becomes weather-dependent, appearing particularly in the colder months or with sudden changes in the weather. Over time the pain interferes with normal walking, and the patient's stride shortens.
Changes within the joint affect the entire muscular and ligamentous complex of the knee. Muscle wasting and joint instability develop which, in advanced stages, can increase the risk of falls and fractures.
Over time the pain is accompanied by clicking or grinding noises in the knee, repeated swelling, joint locking and clinically visible deformity. Diagnosis requires an orthopaedic consultation and imaging (X-rays and MRI).
Primary gonarthrosis generally begins between the ages of 40 and 50, particularly in post-menopausal women who are overweight and have varicose veins in the legs. Studies show that the risk of gonarthrosis in women is 3–4 times higher than in men. Even though the figures fall more heavily on women, men are not spared the condition.
Among the general factors that favour the development of osteoarthritic changes, the following are worth noting: endocrine disorders (ovarian insufficiency, menopause), metabolic disorders (particularly obesity, which acts both by damaging the articular cartilage and mechanically, through excess weight and ligamentous hyperlaxity) and certain genetic factors (a genetic fragility of the articular cartilage, to which patellar and femorotibial dysplasia are added).
Causes:
a) Trauma (the after-effects of fractures, dislocations, sprains, meniscal injuries), which leaves behind damage and imbalance in the bones, joints, capsule and ligaments, favouring the onset of the degenerative osteoarthritic process.
b) Mechanical problems: malalignment of the femorotibial axis, with consequent overload in varus or valgus, is a mechanical stress that can trigger and accentuate osteoarthritis. Gonarthrosis is four times more common in people with genu varum or valgum than in those with a normal femorotibial axis.
Gonarthrosis can also be caused by the secondary effects of malalignment of the extensor mechanism (patellar dysplasia, patellar dislocations and subluxations). The ligamentous apparatus — which maintains the constant contact between the joint surfaces needed for weight to be distributed evenly — can then no longer be held correctly.
Other factors leading to gonarthrosis:
Genetic inheritance also plays an important role in the development of osteoarthritis, through qualitative defects in the articular cartilage. This usually takes the form of generalised osteoarthritis, characterised by premature cartilage degeneration in several joints.
The most important thing to know is that there is no curative treatment for gonarthrosis. In most cases the treatments below need to be combined, and only an orthopaedic surgeon can advise on that.
It is extremely important to prevent gonarthrosis, particularly by maintaining a healthy lifestyle and an ideal weight from a young age. Physical exercise improves joint mobility and prevents wasting of the muscles around the joint. Going to the swimming pool is good for both body and mind and can help prevent the disease. Pay attention, however, to how the exercises are performed — they must be done correctly and in moderation.
There is no definitive remedy, but therapies can relieve symptoms and slow the degeneration:
These conservative treatments can delay the early need for surgery, which can range from simple to complex:
The orthopaedic surgeon decides on the indication for surgery after a specialist consultation (a discussion with the patient and imaging investigations), for which you need to book in advance.
Dr. Codorean offers a precise diagnosis and a personalised treatment plan.