Fewer bones means less risk of bone loss

A common knee replacement technique can dramatically reduce the risk of deadly bone loss and a potentially fatal complication. The technique uses microscopic images of bone cells to map the way in which tumors and joints deform. Published today in the journal JAMA Open Network the study was carried out by researchers at Lund University in Sweden.

Bone-replacement from the hip knee or ankle is relatively safe and provides long term feel-good therapy for people who suffer from osteoarthritis a common joint disease that is estimated to cause up to 29 000 new cases of elderly and severe disability yearly. Unfortunately bone-replacement surgery does not provide the same therapeutic benefit for osteoarthritis patients as traditional procedures and other common methods of treatment.

According to experts when patients can lose the ability to walk independent of the affected hip or ankle the only option available for them to regain sensation and quality of life is to have a bone-replacement surgery. The surgery however may come with long-term physical and cognitive side-effects such as osteoarthritis and joint pain. To date few studies have been carried out on the probability and severity of complications and post-surgery death outcomes following bone replacement surgery.

In the new study the authors examined data on the relationship between bone-replacement surgery and hip fracture severity in 2583 patients. The average age of patients was 62 years and 83 of the patients were male. Most of the patients were followed up for another 4-year period.

When examining the data the researchers identified a slight increase in bone marrow infections and cell death (excess dead cells) after knee replacement surgery. Bone marrow infections were found in approximately 1 of patients. Oxidative stress defined as high levels of free radicals (a type of toxic or reactive oxygen species in the body) were found in 4 of the patients and the rate of tissue scarring in the hip was significantly lower (3. 36 compared to 8. 27 after hip replacement surgery).

Joint pain was assessed by patients having an MRI scan. The authors found it more prominent in women (5. 78) and in those who suffered more severe pain (4. 55) but did not find this difference in men. Bone-replacement surgery did not lead to any significant difference when compared to a control group (2. 92 compared to 3. 97). These preliminary results provide some data about the potential benefits and they need to be followed up on in a much larger sample. However the results suggest that the procedure may allow people with osteoarthritis to have a significantly reduced risk for hip fracture due to replacement of the trochlear cartilage with either the left or right side of the drilled transverse. 1

The study was also carried out on an independent group of osteoarthritis patients who had been taking conventional knee replacement therapies for the previous 4 years.