Osteoarthritis (OA) has long been recognized as a degenerative disease occurring in the elderly population, a group of diseases with different etiologies but similar biological, morphological and clinical features. The incidence of OA in the knee is relatively high. Knee OA refers to a degenerative disease in which primary or secondary degeneration and structural disorders occur in the cartilage of the articular surface of the knee joint, accompanied by subchondral osteophytes and cartilage exfoliation, resulting in the gradual destruction and deformation of the joint, and ultimately the occurrence of knee dysfunction, which leads to pain and disability that seriously impairs the quality of life of patients and has become one of the serious socioeconomic burdens faced by society. As our population gradually enters the ageing era, the incidence of OA is expected to increase.
Knee osteoarthritis etiology.
1, chronic strain: long-term poor posture, weight-bearing force, excessive weight, resulting in soft tissue damage to the knee joint.
2, trauma: frequent knee injuries, such as fractures, cartilage, ligament damage.
3, imbalance of forces on the joint surface: some factor such as trauma, strain or poor posture.
Clinical manifestations.
1, slow onset, mostly seen in middle-aged and elderly obese women, often with a history of exertion.
2. The pain is aggravated by knee joint activity, characterized by paroxysmal pain at first, then persistent pain, more so at night and during exertion, and obvious pain when going up and down stairs.
3. The knee joint activity is limited, or even limping. Very few patients may develop interlocking phenomenon or knee joint effusion.
4. There may be popping and grinding sounds when the joint moves, and some patients have swollen joints.
Signs and examinations.
1. There is obvious pressure pain at the knee patella, and atrophy of the quadriceps muscle is visible.
2.X-ray film shows hyperplasia of the internal and external condyles of the tibia and femur, intercondylar spine and calcification of the patellar ligament.
3.Patellar grinding test was positive.
4, Laboratory tests: blood and urine routine were normal, blood sedimentation was normal, anti-“O” and rheumatoid factor were negative, and joint fluid was non-inflammatory.
Diagnostic points
1. History of repeated strain or trauma.
2. Knee pain and stiffness, more obvious when waking up in the morning, relieved by activity, aggravated by more activity, relieved by rest.
3. Late pain persists, joint activity is significantly limited, quadriceps muscle atrophy, joint effusion, and even deformity and intra-articular free body.
4. Friction sounds can be detected during knee flexion and extension activities.
5. Frontal and lateral x-rays of the knee joint show lip-like osteophytes on the joint margins of the patella, femoral condyles, and tibial plateau, sharp tibial intercondylar ridge, narrowing of the joint space, dense subchondral bone, and sometimes intra-articular free bodies are seen.
Differential diagnosis.
1, chondromalacia patellae: the greater the knee activity, the more pronounced the pain, and there is hyperextension pain and weakness in walking. There is pressure pain on the anterior, inferior, medial, lateral and N fossa of the knee. When the knee is extended with pressure on the patella, friction and pain can be palpated. Patellar grinding test is positive.
2. Lateral collateral ligament injury of the knee: there is fixed pressure pain at the site of ligament injury, often at the upper and lower attachment points of the ligament or in the middle. The knee joint is in a semi-flexed position, with limited movement of the joint. Positive lateral squeeze test.
3, knee meniscal injury: history of trauma, post-injury joint pain, swelling, popping and interlocking phenomenon, pressure pain in the internal and external space of the knee. In the chronic phase, the quadriceps muscle atrophy is especially obvious in the medial quadriceps. The McDonald’s sign and grinding test are positive.
4. Subpatellar fat pad injury: history of trauma, strain or cold in the knee. The pain in the knee joint, especially in stairs, is aggravated by knee hyperextension, the pressure pain in the infrapatellar fat pad is obvious, the knee hyperextension test is positive, the patellar tendon relaxation pressure pain test is positive. x-ray lateral knee film, the texture of the fat pad scaffold is thickened, and a few fat pad calcification shadows are visible.
Treatment.
1, non-steroidal analgesic and anti-inflammatory drugs: mainly play an analgesic and anti-inflammatory role, which can effectively relieve pain.
2, sodium hyaluronate knee cavity injection: sodium hyaluronate knee is the main component of the synovial fluid of the joint cavity, one of the components of the cartilage matrix, which plays a lubricating role in the joint and reduces the friction between tissues. The injection in the joint cavity can significantly improve the inflammatory reaction of the synovial fluid tissue, enhance the viscosity and lubricating function of the joint fluid, protect the joint cartilage, promote the healing and regeneration of the joint cartilage, relieve pain and increase the joint Mobility. It is often injected intra-articularly, 25mg once, once a week for 5 weeks, with strict aseptic operation.
3.Glucosamine: Glucosamine is the most important monosaccharide that constitutes polyglucosamine (GS) and proteoglycan in the cartilage matrix of joints. Glucosamine can block the pathogenesis of osteoarthritis, promote the synthesis of proteoglycans with normal structure in chondrocytes, and inhibit the production of enzymes (such as collagenase and phospholipase A2) that damage tissue and cartilage, reduce damage to chondrocytes, improve joint movement, relieve joint pain, and delay the course of osteoarthritis. Take 250-500mg orally once, 3 times a day, best taken with meals.
4.Knee arthroscopy.
5.Knee joint replacement: for long-term non-surgical treatment is ineffective, serious deformation of the joint, affect the life of reliable knee joint replacement.