Osteoarthritis (OA), also known as degenerative arthritis, osteoarthrosis, and osteophytes, is a chronic, progressive disease that occurs after middle age and is characterized by a loss of cartilage in the synovial joints with periarticular osteophytes. It is called osteoarthritis of the knee when the pathological changes of osteoarthritis occur in the knee joint, resulting in the gradual destruction of the joint, affecting the function of the knee joint and producing deformities. Osteoarthritis of the knee is one of the common joint diseases, and more than half of the knee pain patients visit the doctor because of osteoarthritis, among which women are significantly more than men. However, osteoarthritis of the knee is indeed one of the diseases that greatly endanger people’s health and seriously affect their quality of life.
1. Etiology
(1) primary and secondary articular cartilage insufficiency
Clinical knee OA can be divided into primary and secondary, primary OA causes are less clear, such as a variety of genetic factors, environmental factors, especially the aging process, normal wear and tear, chronic injury, obesity, diet and other factors may be the pathogenesis; secondary OA causes degenerative changes in cartilage for the direct cause of structural changes, inflammation, metabolism, etc..
From modern medical research, the pathology of the disease is characterized by slow, progressive degeneration of the articular cartilage of the lesion. The initial factor that triggers the disease is the change in the biomechanical balance of the knee joint leading to changes in joint stress, which causes metabolic disorders in the articular cartilage cells. This results in the production of various proteases and other local factors that break down the glial and proteoglycans in the cartilage matrix, with catabolism being greater than anabolism, resulting in loss of cartilage matrix and even total cartilage ablation. New bone is formed on the joint surface, at the edges and under the cartilage. Cartilage degeneration and wear, osteosclerosis, cystic changes, bone redundancy formation, and joint hypertrophy and deformation constitute the pathological core of osteoarthritis, leading to a series of clinical symptoms associated with it.
In addition, various factors such as strain and trauma lead to aseptic inflammatory changes in the synovial membrane of the knee joint, and the inflammatory involvement of the synovial membrane is one of the important factors that accelerate cartilage lesions and induce clinical symptoms.
(2) Elevated intraosseous pressure is an extremely important part of the disease process
The abnormal intraosseous hemodynamic forces characterized by intraosseous venous stasis and the resulting changes in intraosseous hypertension play an important role in the pathogenesis of osteoarthrosis of the knee.
2. Diagnosis of osteoarthritis of the knee
Patients usually describe impairment and pain when walking, running and jumping, going up and down stairs, active extension and flexion, etc. Currently, clinical orthopedic surgeons generally use medical history, clinical symptoms such as knee pain and X-ray bone redundancy as several elements for diagnosis, while those without knee pain are not counted as clinical knee osteoarthritis despite the presence of relevant X-ray performance. The most common types of degeneration are: lip-like bone growth on the tibial plateau, increased tip, narrowing of the joint space, lateral tibiofemoral displacement, greater lateral intercondylar bulge than medial, and hyperplasia of the femoral condyles or patellar upper and lower poles. Clinically, knee degeneration is found to be more pronounced on the medial side.
In addition, doctors will pay high attention to the physical signs of their knee joints, such as pressure points around the knee joint, patellar mobility, the degree of floating patella, the degree of patellofemoral joint grinding pain bone grinding sound, and bone joint swelling, which help to improve the clinical diagnosis of this disease.
With the continuous development and updating of domestic and foreign knee osteoarthritis diagnostic techniques, it provides the necessary conditions for early clinical diagnosis of knee osteoarthritis. It is worth highlighting that arthroscopy, the fastest growing technique in recent years, is the most specific and sensitive technique for diagnosing osteoarthritis of the knee, as it allows direct visual inspection of the joint cavity. Magnetic resonance imaging (MRI) is a non-invasive technique that can show the changes of articular cartilage, meniscus, ligament, synovium, free body and bone in osteoarthritis more accurately, especially in its three-dimensional image can show the early small bone formation, the degree of diagnostic accuracy is significantly better than CT and X-ray plain film and B ultrasound, and the results are basically the same with arthroscopic examination, which is conducive to improving the heterogeneity of osteoarthritis of the knee joint It is conducive to improving the understanding of the heterogeneity of knee osteoarthritis and achieving the purpose of individualized treatment. The disadvantage is that it lacks the specificity and sensitivity of arthroscopy for the diagnosis of cartilage degeneration and is expensive.
3. Treatment of osteoarthritis of the knee
Through years of clinical research on osteoarthritis of the knee, we have found that individualized treatment, thorough understanding of each patient’s condition and its causes and consequences, seizing the time for treatment, active treatment of early symptomatic osteoarthritis of the knee, and highly individualized use of conservative, minimally invasive arthroscopic surgery and other mature ladder treatment programs can generally achieve more satisfactory results.
(1) Self-conditioning and functional exercise
In patients with early symptomatic knee osteoarthritis, medication is not the mainstay, but rather patient education and self-conditioning should be emphasized. Patients should be made aware that, in addition to ageing, trauma, obesity, inflammation, metabolism, genetics, endocrine abnormalities and poor biomechanics are all factors associated with the development and progression of the disease. Therefore, patients need to be cautioned to eliminate or avoid unfavorable factors, and weight loss treatment for overweight individuals in particular should be taken seriously. One study suggests that a 5 kg weight loss over 10 years can reduce the incidence of symptomatic knee osteoarthritis by 50%. Encourage patients to treat the disease with a positive and optimistic attitude, regulate the intensity of labor, pay attention to the protection of the knee joint, do not do the same action for a long time, such as squatting, bicycling, etc., when the pain occurs should immediately stop the knee action, the use of handles, canes, knee pads, wedge-shaped insoles or other auxiliary facilities to reduce the load on the affected joint, muscle exercise to increase the stability of the joint, etc., are conducive to disease recovery and disease control.
For early symptomatic knee osteoarthritis, non-weight-bearing quadriceps strengthening exercises can be very helpful. Early osteoarthritis of the knee exhibits muscle weakness in the flexor and extensor muscles, which is primarily a consequence of joint-derived muscle inhibition. The quadriceps function primarily through the patella to confer stability and function to the knee joint.
(2) Western pharmacological treatment of osteoarthritis of the knee joint
Analgesics, NSAIDs and local hormone injections are fast-acting symptom relievers, mainly for pain relief and symptom improvement.
Chondroprotective agents are drugs that slow down, stabilize and even reverse the degradation of osteoarthritic cartilage. These drugs are also slow-acting drugs, which can both relieve pain and improve joint function and have a disease-modifying effect, such as hyaluronic acid and glucosamine hydrochloride.
Currently, sodium hyaluronate injections are widely used in clinical practice to relieve joint pain and swelling and improve joint function, and are safe and well tolerated. We found that sodium hyaluronate has the best effect on mild knee osteoarthritis disease, medium-sized osteoarthritis disease can relieve clinical symptoms for a period of time, for advanced degeneration is less effective, clinical use depending on the specific situation.
(3) Integrated Chinese medicine treatment plan for knee osteoarthritis
We have found through long-term clinical use that the integrated use of Chinese herbal medicine external wet compresses, physical therapy (Chinese medicine package, laser, intermediate frequency), acupuncture closure and intravenous drug delivery, etc., can also achieve good results for moderate knee osteoarthritis, and even severe patients.
(4) Minimally invasive arthroscopic surgery
Minimally invasive arthroscopy is currently the safest and most effective method for osteoarthritis. This technique can clean the affected joint, remove cartilage debris, polish irregular joint surfaces, and remove synovial membrane that has accumulated in the joint for a long time, thus relieving symptoms. In addition, for patients with meniscus and cruciate ligament damage and cartilage destruction, treatment such as meniscal repair, ligament reconstruction and chondroplasty can be done via arthroscopy, which can effectively relieve pain, improve joint function and achieve significant results.
(5) Open surgery treatment
Surgery can be considered for those with severe lesions, persistent pain and obvious dysfunction. Surgical methods include artificial joint replacement, osteotomy, bone fusion, joint orthopedic surgery and joint fixation. The choice of surgical approach is based on a variety of factors, including the patient’s age, the affected joint, the desired goal, the patient’s expectations, and the degree of cartilage destruction. Arthroplasty for patients with advanced disease is an accepted and effective treatment at this stage, which can really relieve patients’ pain, improve function and quality of life.