Knee replacement surgery is one of the greatest surgeries of the twentieth century, offering the possibility of pain relief and improved quality of life for a wide range of patients with severe knee disease. How to make this possibility a reality requires perfect postoperative management. Therefore, the following text has been written based on the author’s experience. I hope it will help those patients who have already had knee replacements to achieve better outcomes.
I. Systematic prevention of venous thrombosis of the lower extremities.
The most serious complication of artificial joint replacement surgery is the occurrence of lower extremity venous embolism (DVT), which can lead to various serious consequences after lower extremity venous embolism, and if it further develops into pulmonary embolism (PE), then the risk of death will be extremely high. Our former Defense Minister Luo Ruiqing died of pulmonary embolism after an artificial hip replacement surgery in Germany.
High risk factors for lower extremity venous embolism
Hip and knee surgery, old age, trauma, previous history of venous thromboembolism, obesity, paralysis, braking, intraoperative application of tourniquet, general anesthesia, malignancy, central venous cannulation, chronic venous valve insufficiency, etc. The more risk factors there are, the greater the likelihood of occurrence. Once, I had a patient who was able to walk on the ground three days after hip replacement and was discharged from the hospital (three weeks after surgery) with a cerebral infarction and then died from complications, which was very unfortunate.
There are three measures to prevent venous embolism of lower limbs.
1.Basic prevention: including encouraging patients to turn over regularly, early functional exercise, getting out of bed, doing deep breathing and coughing action. Drink more water to avoid dehydration. Improve lifestyle, such as quit smoking, quit alcohol, control blood sugar and blood lipid.
2.Physical prevention: Use gradient pressure elastic stockings, etc., using mechanical principles to accelerate venous blood flow in the lower limbs, reduce blood retention, and reduce the incidence of deep vein thrombosis in the lower limbs after surgery. During my training in Germany, I found that German doctors generally use 15cm wide elastic straps instead of elastic stockings to achieve good results, and also have better cost performance. This method is also commonly used in our orthopedic center.
3, drug prophylaxis: two methods can be used: oral rivaroxaban tablets or subcutaneous injection of low-molecular heparin, oral rivaroxaban will be more convenient and safer, but the cost is higher. So the anticoagulation for 6 weeks after surgery is very important.
Active rehabilitation
Many knee replacement patients often have knee extension deformity and inversion deformity before surgery. At this time, the muscles and tendons around the knee joint are contracted. After surgery, the deformity of the knee joint is corrected, which can cause the contracted tendons to become particularly tight. Even if they are released at the time of surgery, it is easy to lose mobility again after surgery due to scar contracture. Therefore, postoperative rehabilitation should be directed at both knee mobility and muscle strength.
Knee mobility training is particularly important within one month after surgery, and it is best to come to the clinic for regular follow-ups as ordered by the surgeon. If it is found that the knee mobility is not recovered satisfactorily and does not reach 90° within 3 weeks after surgery, you will need to return to the hospital for intensive rehabilitation. If this time is missed, rehabilitation will become particularly difficult.
A good joint should be stable, strong and flexible. Joints that are not rehabilitated tend to have reduced range of motion and insufficient muscle strength. Inadequate muscle strength tends to make it easier to fall, and once a periprosthetic fracture is caused, it will be very tricky to deal with, so take care to avoid it as much as possible.
Third, there are still some discomfort after knee replacement surgery
1. About pain
Does it not hurt after knee replacement surgery? In fact, there are many causes of knee pain, some of which cannot be solved by surgery. For example, sciatica manifests itself as radiating pain at the back of the knee joint. For example, radiating pain on the inside of the knee caused by hip disease. Of course, there is also pain caused by surgery-responsive edema early after surgery, and this pain can cause a series of problems if it is not well controlled. First, the pain can cause poor sleep, poor eating and irritability, which can affect rest. Second, severe pain will seriously affect the rehabilitation training, because, muscle training and mobility training will bring pain, pain will obviously make the patient have a burden of thought, will be averse to rehabilitation. If rehabilitation is not active, it is difficult for the reactive edema to subside after surgery. The trip is a vicious cycle, and to interrupt this cycle of nausea requires effective analgesia. We generally recommend a combination of an NSAID analgesic + a myorelaxant. Some sensitive patients also require short-term home use of tramadol tablets. It is relatively common to also need analgesic treatment in the 3-4 months after surgery and there is no need to be nervous.
2. About swelling
Swelling is common after knee replacement, but the degree of swelling varies from person to person and can be influenced by many factors. One thing is for sure though, the better the rehabilitation is done, the faster the swelling will subside. In some elderly people who have had knee pain for a longer period of time, the atrophy of the quadriceps muscle will be more pronounced, whereas the bony structure of the knee will not atrophy and the knee will look particularly swollen in comparison. There is no need to worry about the swelling in particular, and the need for some anti-inflammatory and analgesic medication will help a little. However, if the swelling is in the lower leg, you need to be especially careful because there is a risk of venous embolism, and it is best to have an ultrasound of the veins of the lower extremities as soon as possible to rule out DVT.
3.About numbness
Every bit of skin on our body is sensed because there are dermal nerves distributed in a tree root-like pattern. The incision of the knee joint inevitably affects the dermatome nerve, so there is a numb area on the outside of the incision. This numbness will gradually become smaller and will be fixed in about a year.
4.About the scar
Generally speaking, the incision will be relatively flat in the early stage. Slowly the scar of the incision will become harder and harder, and some of them will be raised, which is quite unsightly. Most of the patients will reach the peak in half a year, and after half a year, it will be softened or flattened. Some people have scars and may have bigger scars.
4. Take a front and side view of the knee in a standing position once a year (X-ray)
To find out if the prosthesis is settling and shifting, and to find out if there is any bone resorption around the prosthesis. To find out if the knee pads are worn.
All artificial joints have a certain life span. Bone resorption leading to mechanical loosening and infection is an important reason for revision. Do not delay treatment as long as your surgeon believes another revision is needed, as delaying treatment will make future treatment difficult. Early detection and early revision can improve the outcome.
Fifth, the following conditions need to be taken seriously: fever, tooth extraction, and bleeding wounds.
Infection is one of the most common causes of prosthetic joint revision. Infections are divided into acute and chronic infections.
After the installation of the artificial joint prosthesis, as long as the bacteria reach the prosthesis around it will not be killed, resulting in uncontrollable infection. Fever, dental procedures, endoscopy, and other minor surgical procedures can produce transient bacteremia, and an important means of preventing late periprosthetic infections is the use of intravenous antibiotics. The use of necessary infection prevention measures can significantly improve the life of the artificial joint prosthesis.
Sixth, pay attention to avoid anti-slip, to avoid accidental injury.
Early postoperative debridement is recommended as early as possible so that the possibility of DVT can be reduced. In the early stage, it is better to use a walker because of pain and lack of muscle strength. Because the ground is slippery and crutches are easy to fall, the use of double crutches is not recommended.
Rational use of walking aids, as shown in the attached figure.
VII. Pay attention to the treatment of osteoporosis, hypertension, diabetes and other underlying diseases.
Doctors want all patients after artificial joint replacement to have a good quality of life. Once, I had a patient who lived a wonderful life for 4 years after bilateral knee replacement, but this patient did not pay attention to the treatment of hypertension, and later had a cerebral hemorrhage, which caused obvious sequelae and required others to take care of his life. This is very regrettable.
The prevention and treatment of osteoporosis begins with the recommendation of bone density testing, and the gold standard for bone density testing is the use of dual-energy X-ray equipment. Our hospital’s bone densitometer is one of the most advanced dual-energy X-ray bone densitometers available and then treatment is based on the bone density report. The first thing to focus on is basic treatment, which includes more exercise, more sunshine, and taking calcium tablets morning and night. If the bone density report T value is less than -2.5, it is recommended to use Calcium D tablets + Fumagal tablets orally, or Zoledronic acid injection is also a good choice. The first treatment phase is recommended to be maintained for one year, and then follow-up treatment will be determined according to the review.
VIII. The following conditions need to be seen as soon as possible
A. Localized redness, swelling, heat and pain of the joint or the appearance of a small hole with fluid flow.
B. Feeling that the joint movement is not as normal or restricted as it used to be.
C. Swelling of the entire limb with pain or joint deformity.
D. The joint appears deformed and painful after trauma.
The presence of these conditions may mean revision surgery.