Zapping nerves in the knee with heat may be a new way to tackle arthritis pain.
Radiofrequency, a type of energy based on radio waves, is being used to destroy small nerves that surround the knee to stop pain signals triggered by arthritis reaching the brain.
Patients who have had knee replacement surgery but still have pain are being given the minimally invasive, non-surgical treatment in a new clinical trial in the U.S.
It is also being given to some arthritis patients as an alternative to knee replacement surgery — a study of more than 60 patients, published last September, suggested the treatment halved pain and other symptoms such as movement difficulties within two weeks.
The ends of the bones that form the knee joint are covered with articular cartilage, a smooth, slippery substance that protects and cushions the bones.
Patients who have had knee replacement surgery but still have pain are being given the minimally invasive, non-surgical treatment in a new clinical trial in the U.S
In osteoarthritis, a wear-and-tear type of arthritis most often seen in people aged 50 and over, the cartilage gradually wears away, resulting in bone rubbing on bone, pain and loss of movement. Treatment ranges from painkillers and physiotherapy to knee braces and total knee replacement with an artificial joint.
Artificial joints can be highly successful but they don’t work for everyone, and studies have suggested ongoing pain is an issue for around 10 per cent of patients (often this is linked to an infection or alignment problems).
Pain signals around the knee are transmitted by branches of the genicular nerve, which lie on the surface of the bones. The radiofrequency treatment is designed to kill the nerve tissue, blocking the transmission of pain signals to the brain.
The patient is given a local anaesthetic or sedation and a thin tube containing a needle, through which the radio waves are delivered, is tunnelled under the skin to the target nerves.
At the press of a button, the radiofrequency is applied to the genicular nerves at a temperature of 70c, for around 90 seconds. Patients can go home the same day (they may experience a few days of localised soreness, but most return to normal activities the next day).
Radiofrequency ablation is widely performed in medicine. It’s used in the heart to destroy abnormal electrical pathways causing heart rhythm problems, and in cancer therapy to treat tumours in the lung, liver and kidney.
In a new clinical trial at the University of Utah, ten patients who have had knee replacement surgery but remain in pain will have the treatment. This is the first trial testing the treatment in patients who have had knee replacements.
But people with knee arthritis who have yet to have surgery can also benefit, according to a study by doctors in Turkey, published last year in the Journal of Anaesthesiology Clinical Pharmacology. More than 60 patients had the treatment and after six weeks, there was an average 50 per cent drop in symptoms.
Commenting on this new approach, Mike McNicholas, a consultant orthopaedic surgeon at Liverpool University Hospitals, said: ‘Pain specialists and orthopaedic surgeons have used nerve-cutting operations to treat some patients, but the nerves can regenerate and cause new, painful problems such as neuromas [a lump on the nerve].
‘These new studies show great promise,’ he says, adding that larger, long-term studies are needed to ensure these problems don’t also occur following this new technique.
Meanwhile, blood injections can significantly improve osteoarthritis symptoms, according to a study in the Australian and New Zealand Journal of Surgery.
A group of 59 patients were given jabs of platelet-rich plasma (made from their own blood that has been spun in a centrifuge to remove the red blood cells). There was an average 60 per cent improvement in symptoms, including pain, in the first month. Patients given a second jab (on average 12 days later) improved more than those who had just one.
The benefits are thought to be due to the anti-inflammatory effect of the plasma — inflammation is thought to drive symptoms and disease progression.
COVID-19 infection can affect male fertility, according to a study from the University of Hong Kong.
Researchers investigated changes to hamsters infected by Covid-19 and found reduced sperm count and testosterone levels and damage to the testicles — all thought to be the result of inflammation.
‘In managing convalescent Covid-19 males, it is important to be aware of possible hypogonadism [low sex drive] and subfertility,’ they said.
Covid-19 vaccination can prevent this complication.
Desserts linked to bowel cancer
Too many sugary, dairy desserts may increase the risk of bowel cancer, warn scientists from the University of Paris.
In a study involving more than 100,000 people, reported in the International Journal of Cancer, they found that these foods were associated with a significantly increased risk in bowel cancer.
No such link was seen with the risk of prostate and breast cancers.
The desserts may fuel weight gain and insulin resistance (when the body’s cells don’t respond properly to the hormone insulin), both of which have been linked to increased bowel cancer risk.
Why it’s hard to start exercising
If you’re had a break from your exercise routine and are struggling to get back into it, you can blame a protein in your body — according to research by the University of Leeds.
This showed that periods of inactivity deactivate a protein, Piezo-1, which only functions as a result of the stress of exercise.
The protein is responsible for sensing the movement of blood and then increasing the density of tiny blood vessels to supply the amount needed for the activity.
The research showed that when mice exercised infrequently, this protein was no longer in action.
If you’re had a break from your exercise routine and are struggling to get back into it, you can blame a protein in your body — according to research by the University of Leeds