Calculate residual limb volume from circumferences
Enter circumferences measured at equal intervals from a reference landmark. Compare two sessions and see the volume change in total and level by level.
Measurements
For example every 4 cm starting from the medial tibial plateau.
| Level | Distance | Session 1 (cm) | Session 2 (opt.) (cm) |
|---|---|---|---|
| 1 | 0 cm | ||
| 2 | 4 cm | ||
| 3 | 8 cm | ||
| 4 | 12 cm | ||
| 5 | 16 cm | ||
| 6 | 20 cm |
Result
Enter circumferences at two or more levels for session 1.
Approximation
The truncated cone model cannot capture the distal end shape or regional differences; volume beyond the most distal level is not included. Socket decisions are made through clinical examination and fitting.
Who are you?
Run this measurement automatically from a scan in your clinic
In a 30-minute demo we'll show the same calculation on a 3D scan, with your own case. Your result is added to the form automatically.
Result added to the form
No calculated result yet — you can still send the form.
Frequently asked questions
How is residual limb volume calculated from circumferences?
The limb is divided into slices by circumferences measured at equal intervals, and each slice is treated as a truncated cone (frustum). A slice's volume is V = h × (C₁² + C₁·C₂ + C₂²) ÷ (12π), where h is the slice height and C₁ and C₂ are the lower and upper circumferences. The sum of the slices gives the limb volume.
Why track residual limb volume?
Especially in the first months after amputation, volume changes as oedema subsides, and it can fluctuate within a day and between days. Volume change directly affects socket fit and helps decide on sock ply adjustments, liner changes or a new socket.
How should measurements be taken?
Start every measurement from the same landmark (for example the medial tibial plateau on a transtibial limb), use the same interval and tape tension, and ideally measure at the same time of day. This keeps two sessions comparable.
Does this replace a 3D scan?
No. Volume from circumferences is a practical approximation, but it cannot capture the distal end shape or regional differences. A 3D scan records the whole surface; in the Clonify socket module, volume and cross-section comparisons are made on the scan.