Prosthetic Feet in Below-Knee Prosthesis
DNB Orthopaedics • October 2024 • Paper IV • 10 Marks
Introduction
The prosthetic foot is the terminal component of a transtibial prosthesis. It replaces several functions of the normal ankle-foot complex, including shock absorption, stability during stance, progression over the foot, accommodation to uneven surfaces and generation or return of energy during push-off.
Selection depends on the amputee's:
- Age and body weight
- Activity level
- Balance and muscle power
- Terrain and occupation
- Residual limb status
- Associated medical conditions
- Cosmetic requirement
- Cost and maintenance considerations
Basic principle
As prosthetic-foot design progresses from a simple non-articulated foot to dynamic-response and powered systems, there is generally an increase in mobility, terrain adaptation and energy return, but also cost, complexity and maintenance.
A. Classification / Designs of Prosthetic Feet
PROSTHETIC FEET
│
├── 1. Non-articulated feet
│ ├── SACH foot
│ └── Flexible-keel foot
│
├── 2. Articulated feet
│ ├── Single-axis foot
│ └── Multi-axis foot
│
├── 3. Dynamic-response / energy-storing feet
│ ├── Flexible keel
│ ├── Carbon-fibre energy-storage foot
│ └── Split-toe / multiaxial dynamic feet
│
└── 4. Advanced feet
├── Hydraulic ankle-foot
├── Microprocessor-controlled ankle-foot
└── Powered ankle-foot
1. SACH Foot
SACH…