Excess Weight Predicts Younger Age at Hip and Knee Replacement


Given that I have put myself out of commission due to a musculoskeletal injury I acquired over the weekend, I thought a discussion of joint injuries and such would be most appropriate in my Robaxocet induced state.

Just last week Travis discussed the issue of injuries associated with exercise among obese individuals. In that post, based on recent evidence, Travis concluded:

"...in overweight and obese individuals, exercise (in the form of walking) has little or no association with injury or illness."

However, there still remains the issue of various musculo-skeletal problems which appear to happen at a high rate among those individuals carrying excess weight, independent of their activity level.

Knee and hip osteoarthritis, for example, are quite commonly listed as a frequent medical consequence of obesity.

A new study from our neck of the woods (Ontario, Canada) sought to determine the effect of weight status on the age at which individuals elected to have knee or hip replacement surgery.

In short, Ghandi and colleagues sorted through a list of patients who had been diagnosed with osteoarthritis and who had undergone surgery to replace their knee(n= 804) or hip joints (n= 841) at the Toronto Western Hospital.

Overall, the average age for a hip replacement surgery was 67.7 years while that for knee replacement surgery was 70.1 years.

And what was the effect of patients' weight status on age of surgery?

In contrast to those individuals with a "normal" body mass index (BMI = 18.5-24.9 kg/m2) individuals with a BMI >35.0 kg/m2 were on average 7.1 years younger at hip replacement and 7.9 years younger at knee replacement.

In a regression analysis, the authors showed that as you move from the normal weight BMI category to overweight, and class 1 and 2 obese BMI categories, there is approximately a 2 year decrease in the age at which one receives knee or hip replacement surgery.

Given that joint replacement surgery often needs to be redone throughout life, one of the major implications of earlier joint replacement surgery in obese patients is the potential for more revision operations over their lifetime.

With regards to the mechanism behind the association, although the simple explanation of greater load from the excess weight being carried is the most popular to explain the relationship between excess weight and joint problems, recent evidence suggests a more metabolic/hormonal rather than mechanical influence of obesity. Indeed, some studies have shown greater osteoarthritis in non-weight-bearing joints of obese individuals, such as the hands.


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Gandhi, R., Wasserstein, D., Razak, F., Davey, J., & Mahomed, N. (2010). BMI Independently Predicts Younger Age at Hip and Knee Replacement Obesity DOI: 10.1038/oby.2010.72


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That's an interesting one, and the studies into the actual cause would be really useful. The increase in OA in non-weight-bearing joints in the obese makes me wonder. I mean, if it is merely the hands, then it could even be associated with a more sedentary lifestyle spent doing fiddly things (like typing on a keyboard), but it makes you wonder.

The excess weight-extra strain on the knees association seems so obvious, we need to remember not to assume it's the cause.

Mr. Brian Troughton, UK

My troubles began when my left leg started to go stiff and to hurt. The doctor told me it was arthritis. The waiting list on the national health was nine to 12 months, so it had to be private. Private in England means big money. So I had to shop around. The first lead we found on the computer was a private company that was sending people to India. For the said operation this company was contacted. But at the end of the pay the price on the computer and the price they wanted to charge me was about 1100 pounds more than they were advertising. So one needs to look into things before signing up. Once again we went back to the computer and came across Dr. A.K.Venkatachalam. So we made contact with the doctor and agreed on a price for the full package- accommodation, food, surgery and physio. We were met at the airport and taken to the hospital.

The physio staff called twice a day to ensure you were making good progress. After I was discharged from hospital, I stayed at a holiday resort which was recommended by Dr.Venkatachalam. It was first class the manager and staff wereA1. The doctor also arranged for another doctor to visit me three times at the resort to keep an eye and the progress of my knees. I also saw our physio twice. My friend Stephen came with me to be of any help he could. It made my life and recovery so much easier, a help above any call of friendship. He will always have my thanks. My colleague was also very impressed with the way everything went. The overall cost was about a quarter of the cost of getting it done in England, and that includes the airfare. I would recommend anyone the hospital and DR.Venkatachalam to help improve their quality of life. Keep up the good work, come up and it was a pleasure and privilege to have met you all.

Thanks for everything, I'm so glad that I spoke to you and found such a wonderful knee replacements treatment. If you need to visit this hospital then feel free here: 1.303.578.0719, info@placidway.com

That's an interesting one, and the studies into the actual cause would be really useful. The increase in OA in non-weight-bearing joints in the obese makes me wonder. I mean, if it is merely the hands, then it could even be associated with a more sedentary lifestyle spent doing fiddly things (like typing on a keyboard), but it makes you wonder.

I really appreciate for the information that you have shared. The studies being made on this really sounds great! Thank you for sharing this and making us aware.