In the ten years from 1996 to 2006, the number of joint replacement surgeries being carried out in the United States exploded; total hip replacements were up 30% and total knee replacements up 70%. And the numbers are expected to continue rising. In Canada, meanwhile, numbers are also on the increase and already waiting times for replacement surgery are viewed by some doctors as being unacceptably long in some situations.
This prompted a group of researchers in Canada to carry out a study to determine what factors actually made a difference to the success of surgery, so that they could help define the criteria for when surgery is appropriate. The findings of the study were published in the April 2013 edition of Arthritis and Rheumatism.
The researchers looked at 202 patients in Canada who had ‘troublesome’ joints and experienced difficulty with some everyday actions like getting up from a chair or climbing stairs. They were asked to rate their pain and mobility before and after surgery.
Some 93% of the patients had osteoarthritis, while the remainder had some form of inflammatory arthritis like rheumatoid arthritis. 83% reported two ‘troublesome’ joints – 33% having three or more – and almost 57% complained of constant back pain. More than 33% were obese and only 30% said they had no other health problems.
After surgery (133 knee replacements and 69 hip replacements), 53.5% claimed good outcomes – defined as clinically important improvement in disability and pain.
According to lead author of the study Dr Gillian A. Hawker, physician-in-chief in the Department of Medicine in Women’s College Hospital in Ontario, the figure (which is way below the 80% to 90% often claimed) appears low because the criteria were very strict and people with other health problems were less likely to be happy because their other problems remained. Also, patients who had already undergone joint replacement surgery in a second joint and were considered more likely to be satisfied and so were not included.
The study gave some insight into the best timing for surgery. It found that patients in the most pain and with the most limitation in mobility experienced the greatest improvement. Dr. Hawker says that it is important to establish the optimal time for intervention but, as yet, no one has been able to establish that.
Dr. Hawker also pointed out that the study found that Body Mass Index had no significant affect on the overall outcome of surgery. While obesity did increase the risk of peri-operative complications, once patients were back home the benefits in terms of reduced pain and disability were the same for both obese and non-obese patients.
Commenting on the study Dr. Wael Barsoum chairman of Surgical Operations and vice-chairman of the Department of Orthopaedic Surgery at the Cleveland Clinic in Ohio, said that most physicians would say that the findings made sense and were fairly obvious but that it was good to have some science to support what they believed to be true. He felt, however, that the study would need collaboration by larger studies.
About the author:
My name is Matthew Morris. I am PR consultant for Circle Parnership.