Unbearable pain after knee replacement

The knee joint can be said to be one of the most complex large joints in the human body. Because it bears most of the body's weight, it is extremely easy to be injured. After some patients suffer from knee necrosis, the hospital will recommend knee replacement surgery. Knee replacement surgery can be regarded as a major surgery in surgery, and the pain level can be regarded as level 10 pain. Will you really be in excruciating pain after knee replacement?

There are three types of pain caused by surgery

It is inevitable that surgery will cause pain. In terms of its occurrence mechanism, surgical pain can be noxious pain, inflammatory pain, or neuropathic pain.

"Nociceptive pain is pain caused by surgical injury directly affecting nerves, which comes from the injury. Inflammatory pain is pain caused by the release of inflammatory factors after local tissue damage, which comes from the tissue at the surgical site. Neuropathic pain is pain caused by pathological changes in nerves caused by injury and inflammation. At this time, the tissue may not be inflamed, and the injury has healed, so the pain comes from the nerves themselves."

Generally, acute postoperative pain is mainly caused by injury, while chronic pain is mainly caused by inflammatory pain and neuropathic pain. Deputy Chief Physician Wang Jian pointed out that the three types of pain have different principles and therefore require different treatments, especially the differences in medication. Only when doctors have a deep understanding of surgical pain can they prescribe the right medicine and achieve good analgesia.

It is a mistake to start pain relief only when the pain is severe

Many people believe that there is no need to take painkillers all the time before and after surgery. Whenever the pain occurs or the pain is severe, just take a painkiller or get a painkiller injection.

Deputy Chief Physician Wang Jian said that this concept is the most common misunderstanding in pain management. At the same time, this misconception leads to a high incidence of chronic pain after surgery.

"Whenever surgery is performed, it will cause tissue damage and may also cause local inflammatory reactions. The inflammatory reaction affects the whole body. In addition to causing pain, it will also affect the healing of the incision, cause neuropathic changes and induce chronic pain, and increase the risk of complications such as thromboembolism, cardiovascular and cerebrovascular accidents, and stress-induced gastric ulcers." Therefore, he said that when the pain is not obvious, it is beneficial to use anti-inflammatory analgesics.

In addition, he also pointed out that due to the plasticity of the nervous system, the inflammatory response after tissue damage makes the pain nerves more sensitive and more prone to explosive pain. Using analgesics when the pain is not obvious or even before surgery can help inhibit the level of inflammatory response, reduce the sensitivity of pain nerves, increase the threshold for feeling pain, and make it less likely for patients to feel pain.

"Stepped" pain control does not lead to drug addiction

Will taking too much painkillers cause addiction? This is also a problem that many patients worry about. Deputy Chief Physician Wang Jian told the editor of Family Doctor Online that there are many types of analgesics, not all of which are addictive. Standardized use can reduce the risk of addiction to a very low level.

"For example, drugs such as Celebrex, Ancomac, Trinacil, and Voltaren are anti-inflammatory analgesics and are not currently considered addictive. However, opioids such as morphine, fentanyl, codeine, and the opioid-like drug tramadol do have varying degrees of addictiveness." But Wang Jian also said that the addictive nature of a drug does not mean that you will become addicted after taking it. He pointed out that under the current analgesia concept, pain control is "step-by-step", and addictive drugs will not be used unless the pain is severe enough.

He explained that the department needs to go through clinical exploration and summary to come up with the specific implementation method. The current analgesic method used is "multimodal analgesia", which is also the most correct analgesic method at present. This approach is based on a deep understanding of pain mechanisms and runs throughout the entire treatment process. According to the mechanism of pain, several different drugs are used for analgesia at the same time, and addictive drugs are only one of them. As a result, the dosage is often very small. In the wards and outpatient clinics of this department, there are almost no patients addicted to analgesics.

In addition, he said it is worth reminding that pain is not just local discomfort, it will have adverse effects on all organ systems of the patient's body. It is called the "fifth vital sign" in addition to body temperature, pulse, respiration, and blood pressure by the World Health Organization. Therefore, doctors need to use analgesics reasonably.