Knee pain

Knee pain- This is a sign of pathological processes affecting the cartilaginous, bone or soft tissue structures of the femorotibial and patellofemoral joints. Arthralgia can be based on trauma, inflammatory and degenerative diseases of the joint system and periarticular structures. Patients may complain of sharp, aching, burning, throbbing and other pains that occur while at rest or when moving, supporting, flexing and extending the leg at the knee. The diagnosis of the causal pathology includes the methods of instrumental imaging (Rg, ultrasound, CT or MRI, arthroscopy), puncture of the joint capsule, biochemical and immunological analyzes. Until the diagnosis is clarified, rest, joint immobilization, NSAIDs, and pain relievers are recommended.

Causes of knee pain

Traumatic injury

They are generally the result of a domestic trauma, often encountered in athletes: runners, jumpers, participants in the practice of a sport. Developed by a fall, direct impact or twisting of the leg. Manifested by sharp pain at the time of injury. In the future, the pain syndrome becomes less pronounced, accompanied by increasing edema. Abrasions and bruises are possible. As the frequency increases, the following injuries are identified:

• Knee injury. . . Occurs by falling to the knee or hitting it directly. At first the pain is sharp, hot, sometimes burning, but bearable, later - dull, aching, worse with movement. Bruising is possible. Leg support is preserved. Sometimes a knee injury is complicated by hemarthrosis, in such cases the joint gradually increases in size, becomes spherical, a feeling of pressure or bursting is added to the pain syndrome.
• Ligament rupture.It is found after twisting of the leg, its forced twisting, flexion or overextension in a non-physiological position. Painful sensations are stronger than with a bruise; simultaneously with the onset of pain, a person can feel how something is torn (in the same way that ordinary tissue is torn). It is accompanied by a significant limitation of movements, support, torsion of the limb, hemarthrosis in rapid increase.
• Intra-articular fractures. . . They are detected by bumps, falls and twists of the leg. In case of injury, a person feels a very sharp, often unbearable pain, sometimes a cracking sound is heard. The intra-articular fracture patients themselves describe their feelings as follows: "The pain is such that it darkens in the eyes, the world ceases to exist, you don't understand anything. Subsequently, the pains become less intense, but remain high in intensity. Support is usually not possible, movement is almost completely limited. Edema and hemarthrosis progress rapidly.
• Dislocation.Is the result of a blow or a fall to the knee. At the time of dislocation of the patella, a sharp pain occurs, accompanied by a feeling of flexion of the leg and displacement of the knee. No movement possible, the reference function can be saved. On the front side of the knee, a pronounced deformation is visible, which is then smoothed out due to the increased edema. Sometimes hemarthrosis joins.
• Pathological fractures. They develop with minor injuries, are a consequence of decreased bone strength in osteoporosis, osteomyelitis, tuberculosis, bone tumors. The pains are painful, dull, reminiscent of pain syndrome with bruising. The signs indicating a pathological fracture are a limitation or inability to support the leg, a feeling of instability in the knee, sometimes a deformation, a bone cracking during movement.
• Damage to the menisci.Meniscus tears are formed during intense forced twisting, impact, flexion or extension of the knee, tight bend with a fixed leg. At first, a person feels a special click and a sharp throbbing pain in the depths of the joint. Then the pain subsides somewhat, but becomes diffuse, sometimes - burning, bursting, intensifies when trying to support and move. The knee volume increases due to edema and hemarthrosis. Support becomes impossible, travel is severely limited.

Inflammatory pathologies

They can be infectious and non-infectious (post-traumatic, toxic-allergic, metabolic, post-vaccination). An abundant blood supply to the synovial membrane and periarticular tissues promotes the rapid development of inflammation in response to direct and indirect effects, and a large number of nerve endings causes a pronounced pain reaction. The inflammatory process is often accompanied by synovitis (accumulation of aseptic fluid in the joint), with infection, pus may accumulate.

• Arthritis.Gonarthrosis occurs after injuries, sometimes complicates infectious diseases, is detected in rheumatic diseases. Can be acute or chronic. Knee pain is usually dull, aching, pressing or pulling. At first, the pain is not intense and intermittent, increasing in the evening or after exercise. Then the initial pains join together, the intensity and duration of the pain syndrome increase. The joint swells, the skin covering it reddens, its temperature rises. With synovitis, the contours of the knee are smoothed, there is a feeling of bursting. With suppuration, the intensity of pain sharply increases, they become contractions, sleep deprivation.
• Synovitis.It is not an independent disease, complicates many acute and chronic pathologies of the joint. It forms in a few hours or days. Initially, the pain is insignificant or absent, a feeling of fullness prevails. The knee is spherical, with a large amount of fluid, the skin is shiny. The movement is somewhat limited. When infected, the pain becomes pronounced, pulsating, convulsive, intensifies with the slightest movement and touch.
• Bursitis.Inflammation of the joint capsules located in the kneecap and popliteal fossa usually occurs when the knee is overloaded and its injuries are repeated (for example, with constant pressure on the knees). With bursitis, the pain is local, dull, not intense, appears at a certain position of the limb, after a characteristic load, decreases when the position of the leg changes, massaging the affected area. If the posterior sac is affected, painful sensations are possible when going up or down stairs. Sometimes minor local edema is determined. With suppuration of the bursa, the pains become sharp, convulsive, stinging, associated with hyperemia, edema of the affected area, symptoms of general intoxication.
• Tendinitis.Usually it is detected in overweight men and athletes, it affects the own ligament of the kneecap. At first, the pain syndrome appears only with very intense effort, then with standard sports loads, then with daily physical activity or at rest. Pain with tendonitis is localized anteriorly just below the knee, dull, pulling, with disease progression, sometimes paroxysmal, accompanied in some cases by slight redness and swelling, aggravated by pressure. The movement is generally complete, less often slightly limited. A tear or rupture of the ligament is possible due to a decrease in its strength.
• Lipoarthritis.Hoff's disease affects the layers of fatty tissue under the kneecap. It is observed with constant overload of the knee or becomes the result of an old injury. Most often it affects athletes, older women. A person complains of dull, aching aches associated with some limitation in extension. With the aggravation of the pathology, the pain begins to bother at night, there is a feeling of instability of the knee, bending of the leg. By pressing on the side of the kneecap, a slight cracking or cracking sound is heard.

Autoimmune processes

The cause of diseases of this group is the production of antibodies to normal cells of the body with the development of aseptic inflammation of immune complexes of the synovial membrane and cartilage, the phenomenon of vasculitis. The pathologies are in most cases chronic, without treatment they are subject to evolution, and are often at the origin of a handicap.

• Rheumatoid arthritis.The defeat is usually bilateral. With minimal activity of the autoimmune process, the pain is weak or moderate, intermittent, pulling, pressing, accompanied by morning stiffness. With moderate activity, the patient complains of periodic prolonged, aching, pressing or bursting pains of moderate intensity, not only during movement, but also at rest. There is stiffness for many hours, moderate recurrent synovitis. With high activity of rheumatoid arthritis, the pain is strong, diffuse, exhausting, wavy in nature, increases in the early hours of the morning. Stiffness becomes constant, a large amount of fluid accumulates in the knees, contractures are formed over time.
• Systemic lupus erythematosus.Arthralgias are often symmetrical, although a joint can be affected. They can occur at any stage of the disease; with a recurrent course of SLE, they resemble rheumatoid arthritis. With low activity of the process, the pain is short-term, not intense, local, aching, pulling. In severe cases, the pain syndrome progresses, the pain is wavy, disturbs nighttime sleep, becomes prolonged, diffuse, increases with movement, associated with synovitis, edema, hyperemia.
• Rheumatism.Joint pain is one of the first manifestations of rheumatic fever, appears 5-15 days after acute infection, affects several joints at once (usually paired). The pains are rather short-lived, but intense, migrate from one joint to another, differing in nature from a pull or pressure to a burning sensation or pulsation. The knees are swollen, hot, the skin covering them is reddened. Travel is severely restricted. After a few days, the intensity of the pain decreases, the movements are restored. In some patients, residual effects in the form of moderate or mild dull aches persist for a long time.
• Reactive arthritis.Occurs more often 2-4 weeks after intestinal and urogenital infections, usually affects one or two joints of the lower extremities, associated with urethritis, conjunctivitis. The development of reactive arthritis is preceded by increased urination, pain and burning in the urethra, tearing and cramping in the eyes. Knee pain is strong or moderate, constant, wavy, painful, pulling, spasmodic, associated with limitation of movement, deterioration of general condition, fever, severe swelling and redness of the affected area. Painful sensations and signs of inflammation persist for 3 months to 1 year, then gradually disappear.

Degenerative-dystrophic processes

They develop as a result of metabolic disorders in the structures of the soft tissues of the joints and periarticulars. They have a chronic course, progressing over many years. Often accompanied by the formation of calcifications, cysts and osteophytes, deformation of the knee surface. With significant destruction of the articular surfaces, they lead to a pronounced impairment of movements and supportive function, become the cause of disability and require the placement of a stent.

• Osteoarthritis.It develops for no apparent reason or against the background of various injuries and diseases, mainly in old and middle-aged people. At first, the pain is mild, short-lived, usually pulling or aching, occurs with prolonged exertion and disappears with rest, often accompanied by a cracking sound. Gradually, the pain syndrome intensifies, the knees begin to hurt "in time" and at night there is a limitation of movement. Distinctive features of knee osteoarthritis are starting pains (it hurts until you "disperse"), periodic attacks of cutting, burning or throbbing pain due to blockade. During periods of exacerbation, synovitis often occurs, in which the pain becomes constant, pressing, bursting.
• Meniscopathy. . . Usually detected in athletes, people whose work involves significant loads on the knee joint. Manifested by deep local pain unilateral inside the knee at the level of the joint space, more often in the outer half of the knee. The pain intensifies during movement and subsides with rest, it may be dull, pressing or pulling. With progression, there are sharp shooting pains when trying to move. On the anterolateral surface of the joint in the projection of pain, a small painful formation is sometimes felt.
• Tendopathies. . . Tendons near the knees are affected. At the initial stage, they are manifested by local superficial pain of short duration at the peak of physical activity. Subsequently, painful sensations occur with moderate, then light loads, limiting the usual daily activity. Pulling or aching pain, directly related to active movement, is not detected during passive extension and flexion of the knee, sometimes accompanied by a cracking or crackling sound. At the level of the lesion, it is possible to probe the site of the greatest pain. Local signs of inflammation (edema, hyperemia, hyperthermia) are insignificant or absent.
• Osteochondropathy.Children and young people are more often affected, the duration of the disease is several years. Usually, they begin gradually with mild lameness or dull, intermittent, not intense pain, aggravated by exertion, disappearing with rest. With the progression of osteochondropathy, the pain becomes sharp, constant, pressing, burning, or stinging, accompanied by severe lameness, limitation of movement, and difficulty resting on the limb. Then the pain gradually decreases, the supporting function is restored.
• Chondromatosis.Usually diagnosed in older men, less often in infants. Chondromatosis of the joints manifests as moderate, dull, wave-like pain, often worsening at night and in the morning. Movement is limited, accompanied by a crackle. Sometimes blockages occur, characterized by sudden throbbing pain, inability or severe limitation of movement. With the development of synovitis, the pains acquire a vivid character, associated with an increase in the volume of the knee, swelling of soft tissues and a local increase in temperature.

Tumors and tumor-like formations

Pain syndrome can be caused by a cyst, a benign or malignant tumor that directly affects joint or periarticular tissues. In addition, knee pain can serve as an alarming signal for hypertrophic arthropathy, paracancrotic arthritis - paraneoplastic syndromes characteristic of lung cancer, breast cancer and other oncological processes.

• Baker's cyst.Represents a hernial protrusion in the popliteal fossa. In the early stages, it manifests itself as unpleasant sensations or a slight local pain in the back of the knee. Against the background of an increase in Baker's cyst due to compression of neighboring nerves, burning or shooting pain, numbness or tingling in the area of the sole of the foot may appear. Symptoms are worse when you try to flex the knee as much as possible. In the popliteal fossa, an elastic and slightly painful tumor-like formation is sometimes felt.
• Benign tumors.Includes chondromas, osteochondromas, non-ossifying fibroids, and other neoplasms. They are characterized by a prolonged asymptomatic course or not very symptomatic, they can manifest themselves by vague and intermittent non-intense local pain. With large neoplasms, a solid formation is felt, sometimes synovitis develops.
• Malignant neoplasms.The most common malignant tumors affecting the joint area are synovial sarcoma, osteosarcoma and chondrosarcoma. They are manifested by diffuse local dull pains, sometimes with a certain circadian rhythm (worse at night). The intensity of the pain increases, they become sharp, cutting, burning or convulsive, spreading along the knee and adjacent tissues, accompanied by deformity, edema, synovitis, expansion of thesaphenous veins, a violation of the general condition, the formation of contracture. Upon palpation, a painful tumor-like formation is determined. When the process is started, the pain is excruciating, unbearable, exhausting, robs you of sleep, and is not eliminated by non-narcotic pain relievers.

Invasive operations and manipulations

Pain syndrome is triggered by damage to the tissue of the knee during invasive procedures. The severity of the pain directly depends on the trauma of manipulations on the knee joint. With the penetration of pathogenic microbes into the joint area, pain is caused by inflammatory changes.

• Handling.The most common procedure is a puncture. The pain after the puncture is short-lived, not intense, quickly subsides, localized in the projection of the puncture, which is usually performed on the outer surface of the knee. After a biopsy, the pain may be convulsive at first, then become dull and go away after a few days.
• Operations.After arthroscopy, the pain is moderate, at first quite sharp, then dull, subsiding after a few days or 1-2 weeks. After arthrotomy, the pain syndrome is more intense, it can persist for up to several weeks due to significant tissue damage. Usually, in the first 2-3 days after the procedures, patients are prescribed analgesics, then the pain becomes weak and gradually subsides.

Psychosomatic conditions

Sometimes arthralgia of the knees occurs in the absence of an organic basis (trauma, inflammation, destruction, etc. ) under the influence of psychological factors. Such pain is believed to play a protective role, as it helps reduce emotional stress by turning experiences into physical sensations. A distinctive feature of these pains is their indeterminate nature, inconsistency, the absence of visible changes, a clear link with physical activity and other objective factors. Meteorological arthralgias are observed in people sensitive to changes in atmospheric pressure.

In addition, irradiation of knee pain is possible with coxarthrosis, lumbar osteochondrosis, Perthes disease, fibromyalgia, neuropathy of the sciatic nerve. However, with these pathologies, pain syndromes from other locations usually appear. Additional risk factors that increase the likelihood of knee joint injury and disease include excess weight, professional sports, hypovitaminosis, metabolic disorders, and old age. Hypothermia, stress, physical exertion, and eating disorders can be contributing factors to exacerbation of chronic pain.

Investigation

The diagnostic search algorithm is based on taking into account the nature of the pain syndrome, its duration, the identification of concomitant symptoms and events preceding the onset of knee pain. During the first visit to a doctor (traumatologist-orthopedist, surgeon, rheumatologist), a visual examination and palpation of the knee, an assessment of the volume of active and passive movements are carried out. Based on the data obtained, in the future the patient may be assigned:

• Laboratory blood tests. . . A complete blood count makes it possible to identify the haematological changes characteristic of an acute infectious and inflammatory process (leukocytosis, increased ESR), eosinophilia, typical of an allergic reaction. Biochemical and serological studies are the most instructive for autoimmune diseases, which are characterized by the formation of specific acute phase proteins and immunoglobulins (CRP, rheumatoid factor, ASL-O, CEC, anti-DNA antibodies, etc. . ).
• X-ray.The basic diagnostic method is the x-ray of the knee joint in 2 projections. The presence of pathology is indicated by changes in the contours of the head and joint cavity, narrowing of the joint space, changes in the thickness of the end plates, the presence of edge defects in thejoint ends of bones, osteolysis and bone destruction. In certain pathologies (trauma to the meniscus, Baker's cyst), contrast arthrography shows the greatest sensitivity.
• Arthrosonography. . . Ultrasound of the knee is a quick, inexpensive, affordable, and very informative diagnostic method. Allows to judge the presence of effusion and free bodies in the joint cavity, to identify damage and pathological changes in periarticular soft tissues (signs of calcification, hemorrhage, etc. ). They help to differentiate with great precision the etiology of joint pain.
• CT and MRI. . . These are the methods of choice for arthropathy of any genesis. They are used for a more detailed assessment of the nature and degree of pathological changes, to identify typical signs of traumatic, inflammatory and tumor lesions of bone structures and soft tissues. CT and MRI of the joints are generally used with limited informational content from other instrumental studies.
• Joint puncture. . . It is performed when there is an indication of the accumulation of exudate or transudate in the joint capsule. As part of the differential diagnosis of inflammatory, degenerative and tumor diseases, a cytological, bacteriological or immunological study of the synovial fluid is carried out. To establish the diagnosis of autoimmune lesions of the knee joint, tuberculous arthritis, synovioma, it is extremely important to take a biopsy of the synovial membrane.
• Arthroscopy. . . The objective of invasive endoscopic diagnosis may be a biopsy sample, the clarification of the diagnostic information necessary during a visual examination of the articular elements. In some cases, diagnostic arthroscopy evolves into therapy (atroscopic removal of intra-articular bodies, meniscectomy, autoplasty of ligaments, etc. ).

Symptomatic treatment

Treatment of the causes of knee pain is carried out differentially, taking into account the identified disease. At the same time, symptomatic care is an essential part of an overall treatment process aimed at reducing discomfort and improving quality of life. Immediately after the injury, it is recommended to apply a cold compress to the knee area - this will help reduce pain sensitivity. Ethyl chloride has a cooling and local anesthetic effect. In all cases, resting the knee helps reduce stiffness. It is necessary to limit movements, to give the leg a position in which the pain is minimal. When walking, a fixation bandage is applied to the knee, immobilization of the limb is possible with the help of a cast.

In an acute period of injury or illness, it is strictly forbidden to massage the knee, apply heating compresses and wear shoes with high heels. The main classes of drugs used for the symptomatic treatment of pain and inflammation are analgesics and NSAIDs in the form of ointments, tablets and injections. The measures listed can only temporarily reduce pain, but do not eliminate the root cause of arthralgia. Therefore, all cases of knee pain require qualified diagnosis and treatment, and some conditions (fractures, dislocations, hemarthrosis) require urgent medical attention. You can not postpone a visit to the doctor if the pain is accompanied by a change in the shape of the knee (swelling, smoothing of the contours, asymmetry), the inability to perform flexion-extensor movements, d'' a sloshing of the kneecap, an alteration of the support of the limb.