Gonarthrosis of the knee joint is the most common localization of a degenerative-dystrophic disease, which is characterized by gradual destruction of the cartilage with subsequent changes in the articular surfaces, which is accompanied by pain and decreased mobility.
The disease is more likely to affect women over 40, especially those who are overweight and have varicose veins of the lower extremities.
The knee joint consists of three divisions:
- medial tibiofemoral;
- lateral tibiofemoral;
- suprapatellar-femoral.
These divisions can be affected by deforming osteoarthritis (DOA) both individually and in combination. 75% of all cases of gonarthrosis are destruction of the medial tibiofemoral division (during movements, it experiences a load that exceeds body weight 2-3 times).
In young patients, only one joint is destroyed more often - right or left (gonarthrosis of the right or left side).
Causes of DOA of the knee joint
Several factors may be involved in the development of degenerative cartilage changes at the same time:
- mechanical overload of the knee joint (some specialties, sports) with cartilage microtrauma;
- consequences of injuries, surgical interventions (menisectomy);
- inflammatory diseases of the knee (arthritis);
- anatomical discrepancies of articular surfaces (dysplasia);
- violation of statics (flat feet, curvature of the spine);
- chronic hemarthrosis (accumulation of blood in the synovial cavity);
- metabolic pathology (gout, hemochromatosis, chondrocalcinosis);
- excess body weight;
- violation of bone blood supply;
- osteodystrophy (Paget's disease);
- neurological diseases, loss of sensation in the limbs;
- endocrine disorders (acromegaly, diabetes mellitus, amenorrhea, hyperparathyroidism);
- genetic predisposition (generalized forms of osteoarthritis);
- violation of type II collagen synthesis.
But in 40% of cases, it is impossible to determine the main cause of the disease (primary arthrosis).
Pathogenesis of gonarthrosis
initial phase
In the initial stage of the disease, the processes of cartilage metabolism are disturbed. Reduces the synthesis and quality of the main structural unit of cartilage tissue, proteoglycans, which are responsible for the stability of the collagen network structure.
As a result, chondroitin sulfate, keratin, hyaluronic acid are washed out of the mesh and proteoglycans with structural defects can no longer hold water. It is absorbed into collagen, whose swollen fibers lead to a decrease in cartilage resistance to stress.
In the synovial cavity, pro-inflammatory substances accumulate, under the influence of which cartilage is destroyed even faster. Articular capsule fibrosis develops. The change in the composition of synovial fluid makes it difficult to deliver nutrients to the cartilage and impairs the sliding of articular surfaces during movement.
Progression of pathology
In the future, the cartilage gradually becomes thinner, becomes rougher, cracks are created throughout its thickness. Bone epiphyses experience an increased load, which provokes the development of osteosclerosis and compensatory proliferation of bone tissue (osteophytes).
This reaction of the body is aimed at increasing the surface area of the joint surfaces and redistributing the load. But the presence of osteophytes increases the discomfort, deformity and further limits the mobility of the limbs.
Microfractures form in the thickness of the bone, which damage the vessels and lead to intracranial hypertension. In the final stage of osteoarthritis, the articular surfaces are completely exposed, deformed, the movements of the limbs are significantly restricted.
Symptoms of gonarthrosis of the knee joint
Osteoarthritis of the knee joint is characterized by a chronic, slowly progressive course (months, years). The clinic grows gradually, without pronounced irritations. The patient can not remember exactly when the first symptoms appeared.
Clinical manifestations of gonarthrosis:
- pain. At first, diffuse, short (with prolonged standing, climbing stairs) and as osteoarthritis progresses, the pain becomes local (anterior and inner surface of the knee), their intensity increases;
- local sensitivity to palpation. Mainly on the inside of the knee along the edge of the ankle space;
- crackling. In stage I it may be inaudible, in stage II-III it accompanies all movements;
- volume increase, knee deformity. As a result of weakening of the lateral ligaments, a person develops an O-shaped configuration of the limbs (clearly seen in the picture);
- mobility restriction. At first, there are difficulties with bending the knee, later - with stretching.
Causes of pain in DOA:
- mechanical friction of damaged articular surfaces;
- increased intraosseous pressure, venous congestion;
- adherence to synovitis;
- changes in periarticular tissues (extension of capsule, ligaments, tendons);
- periosteum thickening;
- phenomena of dystrophy in adjacent muscles;
- fibromyalgia;
- compression of nerve endings.
In contrast to coxarthrosis, knee DOA may exhibit spontaneous regression of symptoms.
Clinical manifestations of stage gonarthrosis:
| Characteristics | I scan | Phase II | Phase III |
|---|---|---|---|
| Pain | Short, most often occurs when the knee is elongated (prolonged standing, walking on stairs) | Moderate, disappears after a night's rest | Stressed, disturbing even at night |
| Restriction of mobility | Not visible | There is a limitation of extension, slight lameness | Continuous flexion-extensor contractures, lameness |
| crackling | not | It is felt on palpation during movement | distance cracking |
| Deformation | absent | Slight deviation of the limb shaft forward, muscle weakness | Valgus or varus deformity. The joint is unstable, atrophy of the thigh muscles |
| X-ray picture | Slight narrowing of the key space, initial signs of subchondral osteosclerosis | Joint space narrows by 50% or more, osteophytes appear | Almost complete absence of joint space, significant deformities and sclerosis of articular surfaces, areas of subchondral bone necrosis, osteoporosis |
A common complication of osteoarthritis of the knee joint is secondary reactive synovitis, which is characterized by the following symptoms:
- increased pain;
- bounce;
- shedding into the synovial cavity;
- increase in skin temperature.
Less common and more dangerous complications include: joint block, osteonecrosis of the femoral condyle, patella subluxation, spontaneous hemarthrosis.
Diagnosis of DOA of the knee joint
The diagnosis of gonarthrosis is based on the patient's characteristic complaints, changes detected during the examination, and the results of additional tests.
To confirm osteoarthritis, it is recommended:
- radiography of the knee joint in two projections (anteroposterior and lateral): the most accessible way to confirm the diagnosis in the advanced stage of pathology;
- Ultrasound: determination of the presence of effusion in the joints, measurement of cartilage thickness;
- synovial fluid analysis;
- diagnostic arthroscopy (visual evaluation of cartilage) with biopsy;
- Computer imaging and magnetic resonance imaging (CT, MRI): the best method for diagnosing DOA in the early stages.
If the doctor has doubts about the diagnosis, it can be described:
- scintigraphy: scan of the wrist after insertion of a radioactive isotope;
- thermography: the study of the intensity of infrared radiation (its strength is directly proportional to the strength of inflammation).
Treatment of knee joint gonarthrosis
The treatment regimen for osteoarthritis combines several approaches: drug-free methods, pharmacotherapy, and surgical correction. The ratio of each method is determined individually for each patient.
Non-drug treatment
In the latest ESCEO (European Society for the Clinical Aspects of Osteoporosis and Osteoarthritis) guidelines on how to treat knee osteoarthritis, experts place particular emphasis on patient education and lifestyle modification.
The patient needs:
- explain what is the essence of the disease, set for long-term treatment;
- learn how to use assistive devices (canes, orthoses);
- describe a diet (for patients with a body mass index greater than 30);
- give a set of exercises to strengthen the thigh muscles and relax the knee joint;
- explain the importance of increasing physical activity.
In the early stages of knee osteoarthritis, physiotherapy treatment methods give good results:
- massage;
- magnetotherapy;
- UHF therapy;
- electrophoresis;
- hydrogen sulfide baths;
- paraffin applications;
- acupuncture.
Pharmacotherapy of gonarthrosis
The use of drugs in DOA is intended to relieve pain, reduce inflammation, and slow the rate of cartilage destruction.
Symptomatic treatment:
- analgesic;
- Non-steroidal anti-inflammatory drugs (NSAIDs) of the COX-2 inhibitor group in the form of tablets or suppositories;
- non-narcotic analgesics (with resistant pain syndrome).
Structure-modifying drugs (chondroprotectors):
- Chondroitin sulfate;
- Glucosamine sulfate.
These drugs can be taken in the form of capsules in courses several times a year, injected intramuscularly or directly into the synovial cavity.
Topical therapy includes close and intra-articular injections of glucocorticosteroids, hyaluronic acid preparations.
In stages I – II of DOA, an important place in complex therapy is the use of NSAID-based ointments, gels, and anti-inflammatory creams. They help reduce the patient's need to take NSAIDs by mouth, thus reducing the risk of digestive tract damage.
Folk remedies
The use of tinctures, decoctions, extracts, topical applications of medicinal plants should be considered as adjunctive methods for the treatment of DOA, folk remedies can not replace the therapy prescribed by the doctor.
Herbs used in osteoarthritis: dandelion, ginger, Jerusalem artichoke, burdock, garlic, sea urchin.
Surgery
Surgical intervention may be required at all stages of gonarthrosis with insufficient effect of medical measures. The most common are endoscopic procedures, in the most severe cases replacement of the endoprosthesis is indicated.
Types of endoscopic interventions:
- review and rehabilitation of the joint: extraction of inflammatory contents from the synovial cavity, cartilage fragments;
- plasma or laser ablation: removal of mechanical obstructions in the synovial cavity;
- chondroplasty.
Corrective periarticular osteotomy is indicated for patients with initial manifestations of deformity of the axial limbs (not more than 15-20%).
The purpose of the operation is to restore normal joint configuration, evenly distribute the load on the joint surface, and remove damaged areas. This procedure allows you to delay arthroplasty.
Indications for replacing the affected area (or the entire node) with an artificial one:
- DOA grade II-III;
- severe axial deformity of the limbs;
- aseptic necrosis of the subchondral bone layer;
- persistent pain syndrome.
Contraindications to knee arthroplasty:
- total joint damage;
- unstable ligament apparatus;
- DOA as a consequence of inflammatory arthritis;
- persistent bent contracture, severe muscle weakness.
In this case, the patient undergoes arthrodesis - a comparison of the knee joint in a physiological position with the removal of articular surfaces. This relieves pain but shortens the leg, causing secondary lesions in the knee, hip and contralateral spine.
prevention
Prevention of premature cartilage degeneration should begin in childhood.
Precautions:
- prevention of scoliosis;
- flat feet correction (shoes with arch support);
- regular physical education (limit heavy sports);
- exclusion of fixed postures at work.