Knee arthritis of the is an inflammatory disease of the knee joint of various etiologies, occurring in the form of monoarthritis or being a manifestation of polyarthritis. Clinical signs include pain at rest and during movements, restriction of function, swelling, hyperemia of the skin over the joint, soreness during palpation, local fever. In the diagnosis of knee arthritis, the data of radiography, ultrasound, MRI, thermography, puncture of the joint with the study of synovial fluid, arthroscopy, synovial membrane biopsy play an important role. Depending on the etiology and nature of the course of the disease, the treatment may include drug therapy, intra–articular injections, immobilization, physiotherapy, physical therapy, in severe cases – surgical treatment.
ICD 10
M13.8 Other refined arthritics
Meaning
Knee arthritis (gonarthritis, gonitis, osteoarthritis) is an acute or chronic inflammation in the knee joint affecting its bone-cartilaginous ends or capsule. The complexity of the anatomical structure and the large magnitude of the load being tested determine the high frequency of knee joint damage, as well as the variety of clinical forms of gonarthritis. According to clinical rheumatology and arthrology, knee joint arthritis accounts for 35%-52% of joint inflammations of various localization. The disease can develop in people of different age groups, but it is more common in people 40-60 years old. Prolonged or recurrent course of knee arthritis can lead to restriction or complete loss of movement in the joint and permanent disability of the patient.
Causes
Taking into account the etiology, there is a distinction between primary knee arthritis, which arose as an independent disease, and secondary, which is a consequence of other diseases.
1 Primary arthritis, as a rule, is the result of injuries (bruises, open wounds, rupture of the knee capsule, damage to the meniscus), which ensure the penetration of infection directly into the joint cavity. Gonarthritis may develop after performing a diagnostic puncture of the knee joint or surgical intervention.
2 Secondary arthritis can occur against the background of:
- systemic diseases (rheumatism, psoriasis, Bekhterev’s disease, SLE, Reiter’s disease, etc.);
- infections (tuberculosis, syphilis, gonorrhea, brucellosis, dysentery, chlamydia, etc.);
- purulent processes of other localization (osteomyelitis, furuncle, phlegmon, erysipelas).
Reactive arthritis develops as a result of a urogenital or intestinal infection. Knee arthritis is often found in patients with hemophilia, sarcoidosis, gout, malignant tumors of internal organs.
Risk factors
Predispose to the development of knee arthritis may be:
- injuries of the articular ligaments, bursitis, tendinitis;
- overweight and obesity;
- heavy physical (including sports) loads;
- hypermobility of joints, flat feet;
- infection, vaccination;
- allergic reaction;
- surgical interventions, abortion or childbirth,
- hypothermia.
Anatomy
The knee joint is formed by three bone structures – the patella, femur and tibia. The articular surfaces of the bones are covered with cartilage, which helps to reduce the friction of the articular surfaces connected to each other. The function of joint stabilization is performed by intra-articular and extra-articular ligaments, and the function of knee cushioning is performed by cartilaginous layers (menisci). All elements of the joint are enclosed in a joint bag, covered from the outside with dense fibrous tissue, and lined from the inside with a synovial membrane producing a small amount of synovial fluid. The knee joint is the largest supporting joint that provides flexion and extension, as well as rotational movements of the lower limb.
Classification
An independent classification of knee arthritis has not been developed. Like arthritis of other localizations, due to the occurrence of gonarthritis, it is divided into primary (which is an independent nosological form) and secondary (associated with other diseases). Taking into account the clinical picture, knee arthritis can be acute or chronic.
According to the etiology, arthritis is divided into:
- infectious (specific, nonspecific, infectious-allergic);
- rheumatoid;
- reactive;
- post – traumatic;
- aseptic.
Depending on the nature of the inflammatory exudate formed, knee arthritis can be serous, serous-purulent and purulent; according to the number of joints involved, unilateral or symmetrical.
Knee arthritis symptoms
Despite the fact that various forms of knee arthritis have their own clinical features, they all have some common symptoms. The main local (articular) signs of gonarthritis include pain, swelling and joint deformity.
Pain in the knee joint (arthralgia) can be of a different nature. In most cases, the intensity of pain increases gradually; at first, pain occurs periodically, increases after physical exertion or in the evening. Sometimes, from the very beginning, patients with knee arthritis note the “starting” pains that develop after a period of rest. Often, pain syndrome is combined with stiffness and stiffness of the affected joint, depriving a person of the ability to move without auxiliary assistance or support.
Knee arthritis has all the signs of an inflammatory process: swelling occurs in the joint area, which makes the knee look swollen and enlarged in volume; there is hyperemia of the skin over the affected area, a local increase in temperature. As a result of pain, swelling and muscle tension, the amplitude of passive and active movements is limited. With the accumulation of a significant amount of exudate, the symptom of patellar balloting is determined.
In various forms of knee arthritis, extra-articular lesions of various systems can be noted: cardiovascular (pericarditis, myocarditis, acquired heart defects), pulmonary (pneumonitis, alveolitis), digestive (enterocolitis), urinary (kidney amyloidosis, glomerulonephritis, CRF), visual (conjunctivitis, keratitis, uveitis), skin (rash) , etc . Knee arthritis can be combined with arthritis of the ankle, hip, shoulder and other joints.
Purulent knee arthritis (joint empyema) is accompanied by a pronounced intoxication syndrome: fever, chills, headache, myalgia. Due to the increase in edema, the contours of the joint become blurry; there are feelings of swelling in the knee joint. The pain is unbearable, both at rest and when moving, forcing the patient to give the limb a forced position (the leg is bent at the knee joint).
Complications
Due to the active or prolonged course of knee arthritis, bone deformities, flexion contracture of the joint, muscle hypotrophy, ankylosis of the knee joint and loss of limb function may develop. Purulent knee arthritis can be complicated by the destruction of ligaments, pathological dislocations, phlegmon capsule of the joint, sepsis.
Diagnostics
When carrying out diagnostic measures, the main efforts should be aimed at identifying the etiology of knee arthritis. In this regard, patients with gonarthritis may need not only the advice of a rheumatologist and an arthrologist, but also an orthopedic traumatologist, a phthisiologist, a venereologist and other specialists. Examination of a patient with knee arthritis begins with an examination, clarification of the anamnesis of the disease, transferred and concomitant diseases.
- Laboratory test. In acute arthritis, clinical blood analysis shows signs of an active inflammatory process (increased ESR, leukocytosis); biochemical blood test – markers of inflammation (CRP, seromucoid, RF); immunological analysis (ELISA) – antibodies to infectious agents.
- Visualization methods. Joint x-ray reveals usuration of the articular surfaces, narrowing of the articular gap, fibrous or bony ankylosis. In the differential diagnosis of gonarthritis and gonarthrosis, an MRI of the knee joint is performed. The nature and amount of articular effusion is specified by ultrasound of the knee joints. Joint thermography, contrast arthrography and pneumoarthrography are of auxiliary importance among hardware studies.
- Invasive diagnostics. It involves a diagnostic puncture with subsequent examination of synovial fluid; if necessary, diagnostic arthroscopy, biopsy of the synovial membrane.
Knee arthritis treatment
In the active phase of the course of knee arthritis, it is shown to limit the load on the lower extremities, immobilization of the affected joint. Patients are recommended to use adaptive devices (walking sticks, orthopedic shoes, knee pads). In order to reduce the load on the joints, normalization of body weight is recommended.
- Medical treatment. It may include antibiotic therapy, taking NSAIDs, chondroprotectors, local rubbing of ointments, dimexide applications. With syphilitic, tuberculous gonarthritis, specific therapy is carried out. In some cases, intra-articular injections of corticosteroids and hyaluronic acid are indicated.
- Physical therapy. In the recovery period, joint therapeutic gymnastics, massage, physiotherapy (pulsed magnetotherapy, ultraphonophoresis, UHF, laser therapy, mud applications, mineral baths, etc.), acupuncture are prescribed.
- Orthopedic operations. If conservative tactics are ineffective in the treatment of knee arthritis, surgical methods can be used: joint lavage, arthroscopic rehabilitation of foci of infection, arthrotomy, joint resection, excision of synovial membranes, knee replacement, etc.
Prognosis and prevention
In general, the outcome and consequences of gonarthritis largely depend on its form, the timeliness of diagnosis, the completeness of the treatment, and following the recommendations of the attending physician. The chronic progressive course of knee arthritis sooner or later leads to a persistent violation of the function of the lower limb and disability of the patient. The most dangerous in its consequences is joint empyema. In many cases, knee arthritis can be prevented by avoiding injuries, excessive physical exertion, hypothermia, preventing excess weight gain, etc. Prevention of secondary arthritis requires adequate treatment of infectious and rheumatic diseases.