BMI Amputees

The background

Obesity time-bomb id "as big a threat to the planet as climate change"

How big is the problem?

In 2008, almost a quarter of adults in England were classified as obese
A greater proportion of men than women in England were classified as overweight in 2008
39% of adults had a raised waist circumference in 2008 compared to 23% in 1993. Women wee more likely hen men to have a raised waist
In 2008, 16.8% of boys aged 2-15, and 15.2% of girls were classed as obese, an increase from 11.1% and 12.2% respectively in 1995
For boys, on week days, the proportion who spent 4 or more hours doing sedentary activities was 35% of those , who were not overweight or obese, 44% of those classed as overweight and 47% of those classed as obese in 2008. For girls, a comparable pattern was found; 37%, 43% and 51% respectively.
Impact of weight on Prosthetic Use
The risks involved of being overweight or obese can effect many areas of the body internally, mentally and also may cause prosthetic limitations. An over bearing body limits the user for choices of artificial limbs and can cause a great strain on the sockets and other supporting parts of the body.

166 subjects were involved (98 male), age 16-96 years (mean = 58.7)
Weight 47-140 kg, (mean = 88)
68 Transtibal 48 transfemoral amputees.
Trauma (49) PVD (29) Others (38).
1-66 years Post Amp, mean = 13.66 years.
Period of use of current prostheses was 0.5-28years, mean = 3.5
101 repairs were done in a period of 6 months.
The number of repairs was found to correlate significantly with weight (P value less than 0.001) and inversely with age (P value = 0.003). No significant correlation was found between repairs and gender, cause of amputation, or level of amputation. Body weight and age of amputee are determining factors in the frequency of repairs of lower limb prostheses

Body Mass index (BMI)

Most widely used diagnostic tool used to identify weight problems within a population

Estimate ideal body weight based on height

BMI can be estimated easily and accurately

Assumption of average body composition

Consideration of limb loss

BMI for amputees

BMI score places people into five categories dependant on their lean body mass

In persons with lower-limb amputation BMI indicators are inaccurate when based on observed body weight

Amputation affects the relationship between weight and height in dependant of the degree of obesity

For a person with limb loss due to amputation body weight is often underestimation

Two alternatives for estimating body weight in a person with an amputation

Weight the amputated portion + add the extra weight

Estimate the weight of the amputated portion


Determine the awareness of people with a limb loss of BMI and their idea of healthy weight

Adjust BMI to estimate the proportion of weight loss as a result of amputation to provide a more accurate representation of a person's weight status.

Through researching the impact of BMI through amputees's and recording their weights properly it has been determined that the figures go as follows:

BMI increased by 1.9 on average (7.4%) min 1.38 Max 2.54
11 out of 25 subjects increased their BMI category