Weight of Lower Limb and Knee
Lower Limb Weight
The entire lower limb (leg amputated at the hip) represents approximately 18.5% of total body weight, while a leg amputated above the knee represents approximately 8.0% of body weight, and a leg below the knee represents approximately 6.5% of body weight. 1
Specific Weight Calculations by Amputation Level
- Foot alone: Represents 1.8% of total body weight 1
- Below-knee amputation (leg below knee): Accounts for 6.5% of total body weight 1
- Above-knee amputation (leg above knee): Accounts for 8.0% of total body weight 1
- Entire leg at hip (complete lower limb): Represents 18.5% of total body weight 1
Practical Examples
For a 70 kg (154 lb) individual:
- Complete lower limb: Approximately 13.0 kg (28.5 lb) 1
- Above-knee amputation: Approximately 5.6 kg (12.3 lb) 1
- Below-knee amputation: Approximately 4.6 kg (10.1 lb) 1
- Foot only: Approximately 1.3 kg (2.8 lb) 1
Knee Weight Component
The knee joint itself does not have a separately defined weight in standard anthropometric tables, as it is included within the overall lower limb measurements. The bone mineral content of the lower limb regions has been measured, showing that regional bone proportions range from 2.9-5.6% of the limb segment weight in both males and females. 2
Clinical Context for Weight Adjustments
- When assessing nutritional status in persons with lower-limb amputation, body weight must be corrected using estimated body weight (W(E)) rather than observed body weight (W(O)) to avoid underestimating BMI and misclassifying nutritional status 3
- The correction formulas account for the missing limb segment percentages listed above to calculate what the person's weight would be with an intact limb 3