Knee pain

Knee pain- This is a sign of pathological processes affecting the cartilage, bone or soft tissue structures of the femoral-tibial 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 pain that occurs at rest or when moving, supporting, bending, and extending the leg at the knee. Diagnosis of the causal pathology includes 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 analgesics are recommended.

Causes of knee pain

Traumatic injury

They are usually the result of domestic trauma, often found in athletes: runners, jumpers, participants in sports. Developed from a fall, direct impact or twist of the leg. Manifested by acute pain at the time of injury. In the future, the pain syndrome becomes less pronounced, accompanied by an increase in edema. Abrasions and bruises are possible. As frequency increases, the following injuries are identified:

• Knee injury. . . It occurs when you fall on your knee or hit it directly. At first, the pain is sharp, hot, sometimes burning, but bearable, later - dull, aching, aggravated by movements. Bruising is possible. The leg support is preserved. Sometimes a knee injury is complicated by hemarthrosis, in such cases the joint gradually increases in volume, becomes spherical, a feeling of pressure or burst is added to the pain syndrome.
• Rupture of the ligament.It is found after the 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 may feel how something is being torn (similar to how normal tissue is being torn). It is accompanied by a significant limitation of movement, support, twisting of the limb, rapidly increasing hemarthrosis.
• Intra-articular fractures. . . They are detected by bumps, falls and twists of the leg. In the event of an injury, a person experiences a very sharp sharp pain, often unbearable, sometimes a crunch is heard. The same patients with intra-articular fracture describe their sensations thus: "the pain is such that it darkens in the eyes, the world ceases to exist, nothing is understood". Subsequently, the pains become less severe, but remain of high intensity. Support is usually impossible, movement is almost completely limited. Edema and hemarthrosis progress rapidly.
• Dislocation.It is the result of a blow or fall in the knee. At the time of dislocation of the patella, sharp pain occurs, accompanied by a sensation of bending of the leg and displacement of the knee. No movement possible, the reference function can be saved. On the anterior surface of the knee, pronounced deformation is visible, which is subsequently smoothed due to increased edema. Sometimes the hemarthrosis joins.
• Pathological fractures.They develop with minor lesions, they are a consequence of a decrease in bone strength in osteoporosis, osteomyelitis, tuberculosis, bone tumors. The pains are aching, dull, reminiscent of the pain syndrome with a bruise. The signs that indicate a pathological fracture are limitation or inability to support the leg, feeling of instability in the knee, sometimes deformity, crunching of the bones during movement.
• Damage to the menisci.Tears of the meniscus form during twisting, impact, intense forced flexion or extension of the knee, sharp turn with a fixed leg. At first, a person feels a special click and a sharp stabbing pain in the depths of the joint. Then the pain subsides slightly, but becomes widespread, sometimes - it burns, bursts, intensifies when trying to support and move. The volume of the knee increases due to edema and hemarthrosis. Support becomes impossible, movements are severely limited.

Inflammatory pathologies

They can be infectious and non-infectious (post-traumatic, toxic-allergic, metabolic, post-vaccinal). The 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 cause a pronounced pain reaction. The inflammatory process is often accompanied by synovitis (accumulation of aseptic fluid in the joint), with infection, pus can accumulate.

• Arthritis.Gonarthritis occurs after injuries, sometimes complicates infectious diseases, is detected in rheumatic diseases. It can be acute or chronic. Knee pains are usually dull, aching, pressing or pulling. At first the pain is not intense and intermittent, intensifying in the evening or after exercise. Then the initial pains come together, the intensity and duration of the pain syndrome increases. The joint swells, the skin on it turns red, its temperature rises. With synovitis, the contours of the knee are smoothed, there is a feeling of bursting. With suppuration, the severity of pain sharply increases, they become twitching, deprive of sleep.
• synovitis.It is not an independent disease, it 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. Movement is somewhat limited. When infected, the pain becomes pronounced, throbbing, twitching, intensifying with the slightest movement and touch.
• bursitis.Inflammation of the joint capsules located in the patella and popliteal fossa usually occurs when the knee is overloaded and its repeated injuries (for example, with constant support on the knees). With bursitis, the pain is local, dull, not intense, appears in a certain position of the limb, after a characteristic load, it decreases when the position of the leg changes, massaging the affected area. If the posterior bursa is affected, painful sensations are possible when climbing or descending stairs. Sometimes a mild local edema is caused. With suppuration of the bag, the pains become sharp, twitching, cooking, combined with hyperemia, edema of the affected area, symptoms of general intoxication.
• tendinitis.Usually detected in overweight men and athletes, it affects the patella ligament itself. At first, the pain syndrome occurs only with very intense exertion, then with standard sports loads, then with daily physical activity or at rest. Pain with tendonitis is localized in front just below the knee, dull, pulling, with the progression of the disease, sometimes paroxysmal, in some cases accompanied by mild redness and swelling, aggravated by pressure. Movement is usually 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 located 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 pains in combination, a certain limitation of the extent. With the aggravation of the pathology, the pain begins to bother at night, there is a feeling of instability in the knee, arching of the leg. When pressing on the side of the kneecap, a soft crunch or creak is heard.

Autoimmune processes

The cause of the diseases of this group is the production of antibodies to normal cells of the body with the development of aseptic immune-complex inflammation of the synovial membrane and cartilage, the phenomena of vasculitis. The pathologies in most cases are chronic, without treatment they are prone to progression and often cause disability.

• Rheumatoid arthritis.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 prolonged, pressing or explosive periodic pains of moderate intensity, not only during movement, but also at rest. There is stiffness for many hours, moderate recurrent synovitis. With the high activity of rheumatoid arthritis, the pain is severe, widespread, exhausting, wavy in nature, increases in the premature hours. 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 one joint may 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, non-intense, local, aching, pulling. In severe cases, the pain syndrome progresses, the pain is wavy, interrupts night sleep, becomes prolonged, diffuse, increases with movement, combined with synovitis, edema, hyperemia.
• rheumatism.Joint pain is one of the first manifestations of rheumatic fever, appears 5-15 days after an acute infection, affects multiple joints at the same time (usually paired). The pains are rather short, but intense, migrate from one joint to another, differ by nature from pulling or pressing to burning or throbbing. The knees are swollen, hot, the skin above them is red. Movement is severely limited. After a few days, the severity of the pain decreases, the movements are restored. In some patients, residual effects in the form of moderate or mild dull pain persist for a long time.
• Reactive arthritis.Most often it occurs 2-4 weeks after intestinal and urogenital infections, usually affects one or two joints of the lower extremities, in combination with urethritis, conjunctivitis. The development of reactive arthritis is preceded by increased urination, pain and burning sensation in the urethra, tearing and cramps in the eyes. Knee pain is severe or moderate, constant, wavy, aching, pulling, twitching, combined with limitation of movement, deterioration in general condition, fever, severe swelling and redness of the affected area. Painful sensations and signs of inflammation persist for 3 months to 1 year and then gradually disappear.

Degenerative-dystrophic processes

They develop due to metabolic disorders in the joint and periarticular soft tissue structures. They have a chronic course, progressing for 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 movement and support function, become the cause of disability and require the installation of an endoprosthesis.

• Arthrosis.It develops for no apparent reason or against the background of various injuries and diseases, mainly in elderly and middle-aged people. At first, the pain is weak, short-term, usually pulling or aching, occurs with prolonged exertion and disappears at rest, often accompanied by a crunch. Gradually the pain syndrome intensifies, the knees begin to ache "with time" and at night there is a restriction of movements. The hallmark features of gonarthrosis are initial pain (it hurts until it "dissipates"), periodic bouts of sharp cutting, burning, or stabbing pain due to blockage. During periods of exacerbation, synovitis often occurs, in which the pain becomes constant, pressing, bursting.
• meniscopathy. . . Usually found in athletes, people whose work places significant loads on the knee joint. Manifested by unilateral local deep pain inside the knee at the joint space level, most often in the outer half of the knee. The pain intensifies during movement and subsides at rest, it can 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. In the initial stage, they manifest themselves with short-term local superficial pain at the height of physical activity. Subsequently, painful sensations arise with moderate, then light loads, which limit normal daily activity. The pain is pulling or aching, directly related to active movements, is not detected during passive knee extension and flexion, sometimes accompanied by a creak or crepitus. In the area of the lesion, the site of greatest pain can be probed. Local signs of inflammation (edema, hyperemia, hyperthermia) are insignificant or absent.
• Osteochondropathy.Children and young people are most often affected, the duration of the disease is several years. They usually begin gradually with mild lameness or intermittent, non-intense dull pains aggravated by exertion, which disappear at rest. As osteochondropathy progresses, the pain becomes severe, constant, pressing, burning, or burning, accompanied by severe lameness, limitation of movement and difficulty in resting on the limb. Then the pain gradually subsides, the support function is restored.
• Chondromatosis.Usually diagnosed in older men, less often in newborns. Joint chondromatosis is manifested by moderate dull wave pains, which often worsen at night and in the morning. Movement is limited, accompanied by a creak. Blockages sometimes occur, characterized by sudden excruciating pain, inability or severe limitation of movement. With the development of synovitis, pains acquire an explosive character, combined 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 the joint or periarticular tissues. In addition, knee pain can serve as an alarming signal of hypertrophic arthropathy, paracancrotic polyarthritis - paraneoplastic syndromes characteristic of lung cancer, breast cancer and other oncological processes.

• Baker's cyst.It represents a hernial protrusion in the popliteal fossa. In the initial stages it manifests itself as unpleasant sensations or mild local pains along the back of the knee. Against the background of an increase in Baker's cyst due to compression of nearby nerves, burning or stabbing pains, numbness or tingling in the area may appear. Symptoms are worse when trying 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.It includes chondromas, osteochondromas, non-ossifying fibroids and other neoplasms. They are characterized by a prolonged or slightly symptomatic asymptomatic course, they can manifest themselves with vague and intermittent non-intense local pain. With large neoplasms, a solid formation is felt, sometimes synovitis develops.
• Malignant neoplasms.The most common malignancies affecting the joint area are synovial sarcoma, osteosarcoma and chondrosarcoma. They manifest as dull local vague pains, sometimes with a certain circadian rhythm (worse at night). The intensity of pain increases, they become sharp, cutting, burning or twitching, spreading along the knee and adjacent tissues, accompanied by deformation, edema, synovitis, expansion of the saphenous veins, violation of the general condition, formation of contracture. During palpation, a painful tumor-like formation is determined. When the process is started, the pain is excruciating, unbearable, exhausting, deprives you of sleep and is not eliminated by non-narcotic analgesics.

Invasive operations and manipulations

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

• Handling.The most common procedure is puncture. The pain after the puncture is short-term, not intense, quickly subsiding, localized in the projection of the puncture, which is usually performed on the outer surface of the knee. After a biopsy, the pain may initially be twisted, then become dull and disappear 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 to 3 days after the interventions, patients are prescribed analgesics, then the pain becomes weak and gradually disappears.

Psychosomatic conditions

Sometimes knee arthralgia 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 transforming experiences into physical sensations. A distinctive feature of such pains is their indeterminate nature, inconsistency, absence of visible changes, a clear connection with physical activity and other objective provoking factors. Meteopathic arthralgias are observed in people sensitive to changes in atmospheric pressure.

In addition, the irradiation of knee pain is possible with coxarthrosis, lumbar osteochondrosis, Perthes disease, fibromyalgia, neuropathy of the sciatic nerve. However, with these pathologies, painful syndromes of other localization usually come to the fore. Additional risk factors that increase the likelihood of knee joint injuries and diseases include overweight, professional sports, hypovitaminosis, metabolic disorders, and old age. Hypothermia, stress, physical exertion, and dietary disturbances can be factors that exacerbate chronic pain.

Investigation

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

• Laboratory blood tests. . . A complete blood count helps to identify hematological changes characteristic of an acute infectious and inflammatory process (leukocytosis, increased ESR), eosinophilia, typical of an allergic reaction. Biochemical and serological studies are more informative for autoimmune diseases, which are characterized by the formation of specific acute phase proteins and immunoglobulins (CRP, rheumatoid factor, ASL-O, CEC, antibodies to DNA, 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 the articular ends of the bones, osteolysis and bone destruction. In some diseases (trauma of the meniscus, Baker's cyst), contrast arthrography demonstrates the greatest sensitivity.
• Arthrosonography. . . Knee ultrasound is a fast, inexpensive, inexpensive and highly informative diagnostic method. It allows to judge the presence of effusion and loose bodies in the joint cavity, to identify damage and pathological changes of the periarticular soft tissues (signs of calcification, hemorrhage, etc. ). They help differentiate the etiology of joint pain with high precision.
• CT and MRI. . . They 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 the typical signs of traumatic, inflammatory and tumor lesions of bone structures and soft tissues. CT and MRI of the joints are usually used with limited information content than 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 performed. To establish the diagnosis of autoimmune damage to the knee joint, tuberculous arthritis, synovoma, it is extremely important to conduct a biopsy of the synovial membrane.
• Arthroscopy. . . The purpose of invasive endoscopic diagnostics can be biopsy sampling, the clarification of diagnostic information necessary during a visual examination of the joint elements. In some cases, diagnostic arthroscopy turns into therapeutic (athroscopic removal of intra-articular bodies, meniscectomy, autoplasty of the 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 a comprehensive treatment process aimed at reducing discomfort and improving the 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, knee rest helps reduce pain. It is necessary to limit movement, to give the leg a position in which the pain is minimal. When walking, a fixing bandage is applied to the knee, immobilization of the limb is possible with the help of a plaster cast.

In the acute period of injury or illness, it is strictly forbidden to massage the knee, apply warming compresses and wear high-heeled shoes. 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 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 emergency medical attention. It is not possible to postpone a visit to the doctor if the pain is combined with a change in the shape of the knee (swelling, smoothing of the contours, asymmetry), inability to perform flexion-extensor movements, ballot of the patella, impaired support of the limb.