Gonarthrosisis deforming arthrosis of the knee joint. It is accompanied by damage to the hyaline cartilage of the articular surfaces of the tibia and femur and has a chronic progressive course. Clinical symptoms include pain that worsens with movement, limitation of movement, and synovitis (fluid accumulation) in the joint. In the later stages, support on the leg is impaired, and a pronounced limitation of movements is observed. The pathology is diagnosed based on anamnesis, complaints, physical examination and radiography of the joint. Treatment is conservative: drug therapy, physiotherapy, exercise therapy. If there is significant destruction of the joint, endoprosthetics is indicated.
General information
Gonarthrosis (from the Latin articulatio genus - knee joint) or deforming arthrosis of the knee joint is a progressive degenerative-dystrophic lesion of intra-articular cartilage of a non-inflammatory nature. Gonarthrosis is the most common arthrosis. Usually affects middle-aged and elderly people, women are more often affected. After injury or constant intense stress (for example, during professional sports), gonarthrosis can occur at a younger age. Prevention plays the most important role in preventing the occurrence and development of gonarthrosis.
Contrary to popular belief, the cause of the development of the disease lies not in the deposition of salts, but in malnutrition and changes in the structure of intra-articular cartilage. With gonarthrosis, foci of calcium salt deposition may occur at the site of tendon attachment and ligamentous apparatus, but they are secondary and do not cause painful symptoms.
Causes of gonarthrosis
In most cases, it is impossible to identify any one reason for the development of pathology. As a rule, the occurrence of gonarthrosis is caused by a combination of several factors, including:
- Injuries. Approximately 20-30% of cases of gonarthosis are associated with previous injuries: tibia fractures (especially intra-articular), meniscal injuries, tears or ruptures of ligaments. Typically, gonarthrosis occurs 3-5 years after a traumatic injury, although an earlier development of the disease is possible - 2-3 months after the injury.
- Physical exercise. Often the manifestation of gonarthrosis is associated with excessive loads on the joint. The age after 40 years is a period when many people understand that regular physical activity is necessary to maintain the body in good condition. When starting to exercise, they do not take into account age-related changes and unnecessarily load the joints, which leads to the rapid development of degenerative changes and the appearance of symptoms of gonarthrosis. Running and intense fast squats are especially dangerous for knee joints.
- Excess weight. With excess body weight, the load on the joints increases, both microtrauma and serious damage (meniscus tears or ligament tears) occur more often. Gonarthrosis is especially difficult in obese patients with severe varicose veins.
The risk of gonarthrosis also increases after previous arthritis (psoriatic arthritis, reactive arthritis, rheumatoid arthritis, gouty arthritis or ankylosing spondylitis). In addition, risk factors for the development of gonarthrosis include genetically determined weakness of the ligamentous apparatus, metabolic disorders and impaired innervation in certain neurological diseases, traumatic brain injuries and spinal injuries.
Pathogenesis
The knee joint is formed by the articular surfaces of two bones: the femur and the tibia. On the front surface of the joint is the patella, which, when moving, slides along the depression between the condyles of the femur. The fibula does not participate in the formation of the knee joint. Its upper part is located on the side and just below the knee joint and is connected to the tibia through a low-moving joint.
The articular surfaces of the tibia and femur, as well as the posterior surface of the patella, are covered with smooth, very strong and elastic densely elastic hyaline cartilage 5-6 mm thick. Cartilage reduces friction forces during movements and performs a shock-absorbing function during shock loads.
At the first stage of gonarthrosis, blood circulation in the small intraosseous vessels feeding the hyaline cartilage is disrupted. The surface of the cartilage becomes dry and gradually loses its smoothness. Cracks appear on its surface. Instead of soft, unhindered sliding, the cartilage "clings" to each other. Due to constant microtraumas, cartilage tissue becomes thinner and loses its shock-absorbing properties.
At the second stage of gonarthrosis, compensatory changes occur in the bone structures. The joint platform is flattened, adapting to increased loads. The subchondral zone (the part of the bone located immediately below the cartilage) thickens. Bone growths appear along the edges of the articular surfaces - osteophytes, which in their appearance on the radiograph resemble spines.
During gonarthrosis, the synovial membrane and joint capsule also degenerate and become "wrinkled. "The nature of the joint fluid changes - it thickens, its viscosity increases, which leads to a deterioration in its lubricating and nutritional properties. Due to lack of nutrients, cartilage degeneration accelerates. The cartilage becomes even thinner and in some areas completely disappears. After the disappearance of cartilage, friction between the articular surfaces increases sharply, and degenerative changes quickly progress.
At the third stage of gonarthrosis, the bones are significantly deformed and seem to be pressed into each other, significantly limiting movement in the joint. Cartilaginous tissue is practically absent.
Classification
Taking into account the pathogenesis in traumatology and orthopedics, two types of gonarthrosis are distinguished: primary (idiopathic) and secondary gonarthrosis. Primary gonarthrosis occurs without previous trauma in elderly patients and is usually bilateral. Secondary gonarthrosis develops against the background of pathological changes (diseases, developmental disorders) or injuries of the knee joint. Can occur at any age, usually unilateral.
Taking into account the severity of pathological changes, three stages of gonarthrosis are distinguished:
- First stage– initial manifestations of gonarthrosis. Characterized by periodic dull pain, usually after significant load on the joint. There may be slight swelling of the joint that disappears on its own. There is no deformation.
- Second stage– increase in symptoms of gonarthrosis. The pain becomes longer and more intense. A crunching sound often appears. There is a slight or moderate restriction of movement and slight deformation of the joint.
- Third stage– clinical manifestations of gonarthrosis reach their maximum. The pain is almost constant, gait is impaired. There is a pronounced limitation of mobility and noticeable deformation of the joint.
Symptoms of gonarthrosis
The disease begins gradually, gradually. At the first stage of gonarthrosis, patients experience minor pain when moving, especially when going up or down stairs. There may be a feeling of stiffness in the joint and "tightening" in the popliteal area. A characteristic symptom of gonarthrosis is "starting pain" - painful sensations that occur during the first steps after rising from a sitting position. When a patient with gonarthrosis "diverges, " the pain decreases or disappears, and after significant stress it appears again.
Externally the knee is not changed. Sometimes patients with gonarthrosis note a slight swelling of the affected area. In some cases, at the first stage of gonarthrosis, fluid accumulates in the joint - synovitis develops, which is characterized by an increase in the volume of the joint (it becomes swollen, spherical), a feeling of heaviness and limitation of movements.
At the second stage of gonarthrosis, pain becomes more intense, occurs even with light loads and intensifies with intense or long walking. As a rule, pain is localized along the anterior internal surface of the joint. After a long rest, the painful sensations usually disappear, and reappear with movement.
As gonarthrosis progresses, the range of motion in the joint gradually decreases, and when trying to bend the leg as much as possible, sharp pain appears. There may be a rough crunching sound when moving. The configuration of the joint changes, as if it is expanding. Synovitis appears more often than in the first stage of gonarthrosis and is characterized by a more persistent course and the accumulation of more fluid.
At the third stage of gonarthrosis, pain becomes almost constant, bothering patients not only while walking, but also at rest. In the evenings, patients spend a long time trying to find a comfortable position to sleep. Often pain appears even at night.
Flexion at the joint is significantly limited. In some cases, not only flexion, but also extension is limited, which is why the patient with gonarthrosis cannot fully straighten the leg. The joint is enlarged and deformed. Some patients experience hallux valgus or varus deformity - the legs become X- or O-shaped. Due to limited movements and deformation of the legs, the gait becomes unstable and waddles. In severe cases, patients with gonarthrosis can move only with the support of a cane or crutches.
Diagnostics
The diagnosis of gonarthrosis is made based on the patient’s complaints, objective examination data and x-ray examination. When examining a patient with the first stage of gonarthrosis, external changes usually cannot be detected. At the second and third stages of gonarthrosis, coarsening of the contours of the bones, deformation of the joint, limitation of movements and curvature of the axis of the limb are detected. When the patella moves in the transverse direction, a crunching sound is heard. Palpation reveals a painful area inward from the patella, at the level of the joint space, as well as above and below it.
With synovitis, the joint increases in volume, its contours become smoothed. A bulge is detected along the anterolateral surfaces of the joint and above the patella. Upon palpation, fluctuation is determined.
X-ray of the knee joint is a classic technique that allows you to clarify the diagnosis, establish the severity of pathological changes in gonarthrosis and monitor the dynamics of the process, taking repeated pictures after some time. Due to its availability and low cost, it remains the main method for diagnosing gonarthrosis to this day. In addition, this research method allows us to exclude other pathological processes (for example, tumors) in the tibia and femur.
At the initial stage of gonarthrosis, changes on radiographs may be absent. Subsequently, a narrowing of the joint space and compaction of the subchondral zone are determined. The articular ends of the femur and especially the tibia expand, the edges of the condyles become pointed.
When studying a radiograph, it should be taken into account that more or less pronounced changes characteristic of gonarthrosis are observed in most elderly people and are not always accompanied by pathological symptoms. The diagnosis of gonarthrosis is made only with a combination of radiological and clinical signs of the disease.
Currently, along with traditional radiography, modern techniques such as computed tomography of the knee joint, which allows a detailed study of pathological changes in bone structures, and MRI of the knee joint, used to identify changes in soft tissues, are used to diagnose gonarthrosis.
Treatment of gonarthrosis
Conservative activities
The treatment is carried out by traumatologists and orthopedists. Therapy for gonarthrosis should begin as early as possible. During the period of exacerbation, the patient with gonarthrosis is recommended to rest for maximum unloading of the joint. The patient is prescribed therapeutic exercises, massage, physiotherapy (UHF, electrophoresis with novocaine, phonophoresis with hydrocortisone, diadynamic currents, magnetic and laser therapy) and mud therapy.
Drug therapy for gonarthrosis includes chondroprotectors (drugs that improve metabolic processes in the joint) and drugs that replace synovial fluid. In some cases, with gonathrosis, intra-articular administration of steroid hormones is indicated. Subsequently, the patient may be referred for sanatorium treatment.
A patient with gonarthrosis may be advised to walk with a cane to unload the joint. Sometimes special orthoses or custom insoles are used. To slow down the degenerative processes in the joint with gonarthrosis, it is very important to follow certain rules: exercise, avoiding unnecessary stress on the joint, choose comfortable shoes, monitor your weight, properly organize your daily routine (alternating load and rest, performing special exercises).
Surgery
With pronounced destructive changes (at the third stage of gonarthrosis), conservative treatment is ineffective. In cases of severe pain, dysfunction of the joint and limited ability to work, especially if a young or middle-aged patient suffers from gonarthrosis, they resort to surgery (knee replacement). Subsequently, rehabilitation measures are carried out. The period of complete recovery after joint replacement surgery for gonarthrosis takes from 3 months to six months.