Calculating Ideal Body Weight for Amputees

When assessing an amputee’s weight, the estimated weight of the limb needs to be taken into account.  The information below is used as part of the body weight calculations for amputees.

  • Body Part
  • Hand
  • Forearm plus hand
  • Entire arm
  • Foot
  • Lower leg plus foot
  • Entire leg
  • Estimated Weight
  • 0.7%
  • 2.3%
  • 5.0%
  • 1.5%
  • 5.9%
  • 16.0%
  • Example Weights for a 150 lb Patient
  • 1.05 pounds
  • 3.45 pounds
  • 7.5 pounds
  • 2.25 pounds
  • 8.85 pounds
  • 24 pounds

Example Calculation

A male patient is 5 foot, 8 inches tall and has a full arm amputation.

The first task is to determine his Ideal Body Weight at the current height:
For a man, use 106 pounds for the first 5 feet and then add 6 pounds for each additional inch:  106 lbs + (6 lbs per inch x 8 inches) = 154 pounds.

Next, find a range of +/- 10% of this weight (not accounting for the amputation):
Range factor:  154 lbs x 0.10 = 15.4 lbs
High range weight:  154 lbs + 15.4 lbs = 169.4 lbs
Low range weight:  154 lbs – 15.4 lbs = 138.6 lbs

Finally, find the Ideal Body Weight range for the amputation using the weight ranges above (for an entire arm amputation, use a body weight factor of 5% – see chart above):
Amputation Factor Weight:  169.4 lbs x 0.05 amp factor = 8.47 lbs
High range weight:  169.4 lbs – 8.47 lbs est amp weight = 160.93 lbs
Low range weight:  138.6 lbs – 8.47 lbs est amp weight = 130.13 lbs

This 5 foot, 8 inch patient with an entire arm amputation has an Ideal Body Weight range goal of approximately 161 lbs to 130 lbs.