Patient’s Guide to Artificial Knee Replacement Surgery
I. What conditions are suitable for knee replacement surgery?
Knee replacement surgery should be performed when the following three conditions are met.
1. Significant knee pain and pain-free walking distance of less than 500 meters;
2. Conservative treatment is not effective;
3. The destruction of the knee joint is obvious on radiographs.
Specific diseases include
(1) Non-infectious arthritis of the knee joint, including rheumatoid arthritis, osteoarthritis, hemophilic arthritis, Charcot arthritis, etc;
(2) Traumatic arthritis;
(3) resting infectious arthritis (including tuberculosis);
(4) A few primary or secondary osteochondral necrotizing diseases.
B. What conditions contraindicate knee replacement surgery?
(1) Paralysis of the muscles around the knee joint;
(2) The knee joint has been fused in a functional position for a long time without symptoms such as pain and deformity. Severe flexion contracture deformity, severe osteoporosis, joint instability, severe muscle weakness, fibrous or bony fusion are not absolute contraindications to surgery.
III. Advantages and disadvantages of the artificial knee joint
The advantages are.
(1) Surgery can be performed on patients with deteriorating knee osteoarthritis and severe deformation.
(2) The surgical treatment period is relatively short, about one month.
(3) The joint pain can basically be completely removed.
The disadvantages are.
(1) It has an effect on sports such as running and bench hills.
(2) After surgery, the knee joint is usually bent at a slightly greater than right angle, about 120 degrees.
(3) After 10-15 years after the surgery, the bone and the artificial joint may loosen and need to be replaced in about 5-10% of cases.
(4) It is very difficult to treat infections in artificial joints. 1% of people have infections after surgery, which require prolonged treatment or even removal of the artificial joint, and joint replacement after the infection is controlled. The rate of infection in the resurfaced joint is higher than in the first surgery.
(5) Wear and loosening of the artificial joint is also a cause of post-operative pain and surgical failure.
(6) The price is more expensive.
Fourth, how to choose a good artificial knee joint?
When a patient decides to use the artificial joint replacement treatment, the question often comes up: what kind of artificial joint is the best artificial joint? It should be said that different patients should choose different artificial joints. Artificial joint prosthesis has very strict requirements for its design, surface treatment, material selection, manufacturing process and packaging; it also requires sufficient clinical practice to confirm the effectiveness of a particular artificial joint. At present, the artificial knee joint has become a very mature artificial joint, both in terms of the prosthesis itself and in terms of the surgical technique.
Artificial knee joints have been widely used in clinical practice and have achieved good clinical results. Choosing an artificial knee prosthesis is very different from choosing other commodities, because once the artificial knee prosthesis is placed in the body it is not easy to “replace” it at will, and even if it is “replaced” the cost is quite large and cannot be measured in money alone. Therefore, the choice of a good artificial joint should be made carefully under the guidance of a specialist.
V. The main process of inpatient treatment
The day of hospitalization and the next day: hospitalization procedures, bed arrangement, medical history and physical examination by doctors, routine tests and examinations before surgery. The day before surgery: pre-surgery conversation and signing of medical documents such as surgery consent form, drug allergy skin test, skin preparation and blood preparation procedures.
On the day of surgery: fasting, catheterization, infusion, and surgery. After surgery, we will keep the infusion tube, urinary catheter and bleeding drainage tube. After surgery: 14 days to remove the stitches, gradually enhance the functional exercise, generally in about 1 week crutches to the ground. V. Post-operative examination Three months after discharge from the hospital to review, take X-rays, to understand the position of the joint prosthesis and stability is good. Six months after the operation and then once again, and then every year to take the film examination. If there is any discomfort, such as redness, swelling, pain or difficulty in moving the joint, or if the joint is injured due to an accident, go to the hospital in time for an examination.
VI. Duration and efficacy of the artificial knee joint
The knee joint is an important joint that has various functions such as walking, running, jumping and squatting. Once the knee joint is diseased, the cartilage of the joint will be destroyed and the surface will become rough or even defective from the original smooth mirror-like surface, which will further deform the bone. As a result, you will experience pain, difficulty walking, limited movement, and limping. If the above disease progresses to a certain level and the joint is destroyed, surgery is required.
Surgery is required. An artificial knee joint is used to replace the damaged joint to restore function such as walking. The greatest benefit of artificial joint surgery is that it eliminates post-operative joint pain, greatly improves the function of the joint, and increases the patient’s quality of life so that he or she can work and live well during their lifetime. A successful prosthetic joint replacement allows you to live a pain-free life and perform daily activities that no other treatment can achieve for a damaged knee. Nowadays, more and more patients are willing to accept the suggestion of artificial joint surgery.
The longevity of the artificial knee joint is determined by two main factors.
The first is the wear and tear of the joint.
The second is the loosening of the prosthesis due to wear particles. The strength and wear resistance of the artificial knee material is generally sufficient for patients for more than 20 years.
Nowadays, the artificial joint can be used for more than 95% of the time after 20 years of placement. Of course, the service life of the artificial joint is also related to many factors, such as the amount of movement of the patient, the choice of artificial prosthesis, the surgeon’s surgical technique and their own conditions.
VII. Treatment of loose or infected artificial knee joints
Once the artificial knee becomes infected or aseptically loose, joint revision surgery is required. There are specially designed hip prosthesis and surgical instruments for revision surgery. Revision surgery is more complex than the initial surgery and may involve bone grafting, changing the type of joint prosthesis or using a special prosthesis. After revision surgery, the vast majority of patients can achieve a satisfactory outcome.
VIII. Protection after artificial knee replacement
After artificial knee replacement, you need to develop good habits of life and activities to maintain the stability of the joint, and learn some simple rehabilitation knowledge to perform joint rehabilitation exercises. It is important to pay attention to the prevention and control of infections, and to actively treat infections such as tonsillitis, skin infections, ringworm, etc. After surgery, you can do exercises such as cycling, walking, dancing and swimming, but strenuous exercises such as running and jumping, as well as long-distance walking and climbing are not encouraged. In addition, some hospitals provide post-operative rehabilitation manuals for patients to refer to.
IX. Rehabilitation after knee arthroplasty
Rehabilitation exercises are essential to the success of total knee replacement surgery. Isometric contraction of the muscles of the affected limb can be performed right after surgery. If the joint is well positioned and fixed, rehabilitation exercises, including straight leg raising, quadriceps and walking exercises, can be started under the guidance of the surgeon and the rehabilitator. Even after full recovery, regular rehabilitation exercises are required.
Procedure for Artificial Knee Joint Replacement
Pre-operative preparation
(1) Routine preoperative examination: electrocardiogram, chest X-ray, blood, urine and stool routine, blood biochemistry, infectious diseases, coagulation function, blood type.
(2)Special examination: full-length film of lower limb, measurement of valgus angle.
(3)Common medical conditions examination and treatment: hypertension, diabetes mellitus, coronary heart disease, thrombotic disease; long-term medication registration.
(4) Search and treatment of systemic infectious lesions: tinea pedis, skin infections, etc.
(5)Pre-operative knee function score: knee function score.
(6) Patient education, choice of artificial joint materials: imported, domestic, movable platform, fixed platform.
(7) Determination of affected knee characteristics: conventional knee replacement, deformed knee replacement (inversion, valgus, extension block, restricted flexion), rheumatoid knee, preserved/unpreserved posterior cross, bone defect repair, revision.
(8) Design osteotomy line according to template drawing.
Surgical routine
(1) Preoperative skin preparation, alcohol disinfection of the knee joint and sterile towel dressing.
(2) Preoperative intravenous antibiotics.
(3) For those with a history of thrombotic disease, preoperative low molecular heparin is routinely used.
(4) Operate without tourniquet under pressure, using intraoperative autologous blood transfusion; trauma irrigator flushing and tourniquet pressure before prosthesis installation; leave negative pressure drainage.
(5) Main procedures: osteotomy → initial soft tissue release and balancing → tibial osteotomy → understanding the posterior femoral condyle line PC, IP through the condyle line, and AP in the anterior-posterior phase axis line → predesigning the distal femoral condyle osteotomy line according to the tibial osteotomy line → distal femoral condyle exostosis osteotomy → predesigning the posterior femoral condyle osteotomy line according to the knee extension gap → measurement of the femoral condyle type → other femoral condyle osteotomy → further soft tissue release and balancing. Posterior femoral condyle osteotomy and posterior joint capsule release → trial fitting → knee mobility and stability determination → patella assessment → patella surface replacement if necessary → platform prosthesis self-positioning → platform bone cavity fabrication.
Postoperative management
(1)Use analgesic pump and give pain medication prophylactically at regular intervals;
(2) Use of equipment to improve blood circulation in the lower extremity;
(3)Negative pressure drainage was left in place for about 2-3 days;
(4) Isometric contraction of the lower limb muscles for 0-3 days; flexion of the knee to 90 degrees after 3 days;
(5) Use intravenous antibiotics for 3-5 days; use low molecular heparin for 7-10 days if there is a history of thrombotic disease; generally do not use hemostatic drugs;
(6) Review blood picture, sedimentation and CRP at 1 day, 1 week and 2 weeks after surgery;
(7) Crutches on the floor 2-3 days after surgery, review X-rays, and stitches removed 14 days after surgery;
(8) Further rehabilitation is described in “Rehabilitation Guideline for Knee Replacement Patients”.
(C) Rehabilitation guidance for knee replacement patients
After artificial knee replacement surgery, correct exercise, reasonable use, careful protection and regular review should be achieved. After knee replacement surgery, knee pain will gradually decrease, strength will gradually increase, range of motion will gradually increase, and local swelling will gradually subside. However, this is a gradual process and the speed of recovery varies from person to person; it is also different for the left and right side of the same person. Generally speaking, the best results are achieved about 1 year after surgery.
Proper exercise: After artificial knee replacement surgery, there are three main exercises: leg press, leg lift and leg bend. Leg press is to press the knee joint straight, you can pad the ankle so that it is suspended at the N fossa and use the weight of the limb itself to press the knee joint straight; you can also press with a weight ranging from 5-15 kg in front of the knee. Straightening the knee joint is an important factor in ensuring that both lower limbs are equal in length, reducing stress on the patellofemoral joint, etc. Leg raising is to exercise thigh muscle strength.
Start with the knee flexed in the seated position, or with the knee padded in the supine position. Straighten the knee joint and keep it straight for 5 seconds and then relax, let the knee joint flex on its own, and count the 1st time silently in your mind; then straighten the knee joint again and keep it straight for 5 seconds, then relax and let the knee joint flex on its own, and count the 2nd time silently in your mind; …… until you exercise 10 times and then rest. The total number of exercises per day varies according to individual circumstances, generally 250-300 times. When you feel that this exercise is easier, you can bundle 1 – 2 pounds of sandbags at the ankle. Leg bending is to exercise the flexion mobility of the knee joint. The exercise can be assisted by CPM machine when you are hospitalized.
After discharge from the hospital, you can exercise with the help of another person: the patient is in the prone position, another person holds the patient at the ankle and bends the patient’s knee joint with slow and continuous force. The patient can also exercise on his or her own: in the supine position with the hip and knee flexed, a long towel is held at the ankle and the knee is flexed by pulling with both hands. Later, knee flexion mobility can be exercised by actively squatting. Generally speaking, knee mobility after artificial knee replacement surgery is generally around 120 degrees, and it is difficult to achieve a full height of flexion of the thigh against the calf. Therefore, the use of a bidet is generally recommended after surgery, and squatting is not recommended. The exercise and rehabilitation process is usually accompanied by mild pain in the muscles and ligaments around the knee joint. Daily adherence to home physical therapy can help to relieve pain and increase the effect of exercise rehabilitation.
This is done by applying fotarine cream (diclofenac sodium cream) to the painful area and then drying it with warm air from a hair dryer for 5-10 minutes each time, 3-6 times a day. Reasonable use: Artificial knee joints have the potential to wear out and loosen after long-term use. To prolong the service life, it is not recommended that patients engage in heavy physical work, and strenuous sports. However, it can be adequately used for general sports and work.
Careful protection: Careful protection is mainly reflected in two aspects.
One is to prevent infection and inflammation;
The second is the prevention of traumatic fractures. The possibility of infection and inflammation in the artificial joint is due to the possibility that bacteria from other parts of the body may be transferred to the artificial joint and cause infection and inflammation.
Therefore, it is important to treat infections in other parts of the body (such as colds, pneumonia, boils, etc.) promptly and effectively. In case of infection and inflammation of the artificial joint, early and decisive surgical treatment is necessary to preserve the artificial joint, otherwise it will be necessary to replace the artificial joint in two stages of surgery. When a traumatic fracture occurs around an artificial joint, the fracture does not heal easily and can easily lead to loosening of the artificial joint. Therefore, it is important to pay more attention to the prevention of trauma in general.
Regular review: Early after the surgery, the patient should be reviewed regularly, usually once every 1-2 months, so that the doctor can guide the patient’s rehabilitation exercises. After the condition is stable, annual review can be done.
1.Pre-operative period Quadriceps (anterior thigh muscles) and Kokonoe muscle (posterior thigh muscles) strength exercise.
2.0-3 days after surgery (mainly rest and pain relief) Elevate the affected limb, move the ankle joint actively or passively (10 times per hour of flexion and extension), and use special equipment to improve blood circulation in the lower limb. Lower limb muscle isometric contraction exercise.
3.3-14 days after surgery (restoration of joint range of motion mainly, followed by restoration of muscle strength) Support crutches and gradually increase the range of motion according to the body’s tolerance. CPM exercise. (At least 90 degrees of flexion before discharge) Sandbag compression when unable to fully extend. Quadriceps (anterior thigh muscles) and Kokonoe muscle (posterior thigh muscles) strength exercise.
4.2-4 weeks after surgery (mainly to enhance muscle strength) strength exercise for quadriceps (anterior thigh muscles) and Kokonoe muscles (posterior thigh muscles). Remove stitches and can be discharged. For those who have not reached 90 degrees of flexion, manipulation release can be performed under anesthesia. Up and down step exercises. (The good leg goes up first, the bad leg goes down first.) Those who are in a position to do so can practice pedaling.
5, more than 4 weeks after surgery At this time, the crutches should generally be gradually abandoned. Continue to quadriceps (anterior thigh muscles) and national cord muscle (posterior thigh muscles) strength exercise. Gait balance exercise. If possible, continue pedaling exercises to achieve 120 degrees of knee mobility.
Quadriceps (anterior thigh muscles) strength exercise method: At the beginning, sit with the knee joint flexed, or supine position with the knee joint padded. Straighten the knee joint and keep it straight for 5 seconds, then relax and let the knee joint flex on its own, count the 1st time in your mind; then straighten the knee joint again and keep it straight for 5 seconds, then relax and let the knee joint flex on its own, count the 2nd time in your mind; …… until you exercise 10 times and then rest.
The total number of exercises per day varies according to individual circumstances, generally 250-300 times. When you feel this exercise is easier, you can tie a 1 – 2 pounds of sandbags at the ankle.
National rope muscle (rear thigh muscles) strength exercise method: At the beginning, prone position will be straight knee joint. The knee joint will be bent hard, and keep the hard bending state 5 seconds after relaxation, let the knee joint straight, the heart silent count for the first time; then again the knee joint will be bent hard, and keep the hard bending state 5 seconds after relaxation, let the knee joint straight, the heart silent count for the second time; …… until the exercise 10 times after rest.
The total number of exercises per day varies depending on the individual, generally 250-300 times. When you feel that this exercise is easier, you can fix a leather band at the foot of the bed, hook the ankle to the band and exercise the flexed knee joint.