Like any medical device, hip implants must be vigorously tested before human use. Hip implants have four separate parts that make up the prostheses; the femoral head, femoral stem, acetabular shell, and acetabular linear. To verify long term strength of hip prostheses designs simple static testing is required to evaluate the compressive, tensile and torsional loading required to fracture a hip prostheses. Fatigue life tests are critical because fatigue failure is more common than catastrophic failure, and it most closely matches in vivo forces. Loading test samples with load-controlled sinusoidal waveforms is most common, and tests last in excess of ten million cycles.
Applicable Testing Standards
- ISO 7206 Hip Implants Tests
- ASTM F1440 Cyclic Fatigue Testing of Metallic Stemmed Hip Arthroplasty Femoral Components Without Torsion
- ASTM F1820 Fatigue Test Machine Modular Acetabular Device
- ASTM F2345 Determination of Static and Cyclic Fatigue Strength of Ceramic Modular Femoral Heads
- ASTM F2580 Fatigue Test Equipment for Hip Prosthesis
Recommended Test Machine
Static and fatigue forces up to 50 kN (11,250 lbf)
Frequency ratings up to 75 Hz
Oil-free, all electric actuator for clean test conditions
Lower purchase, operating, and maintenance costs than hydraulic equivalents
Force ratings up to 50 kN (11,250 lbf) and torque ratings up to 180 Nm (1,600 lbf∙in) Can apply axial and torsional loads simultaneously Performs both static and dynamic tests All electric and oil-free operation
Static and fatigue forces up to 25 kN (5,500 lbf)
Frequency ratings up to 100 Hz
Servohydraulic
Small, portable footprint
Recommended Testing Accessories
Rated from ambient temperatures to 1,200°C (2,200°F)
Designed in accordance to ISO 7206
Accommodates different specimen angles, and x- and y-positions
Designed in accordance to ASTM F2580
Accommodates different specimen angles, and x- and y-positions
Allows for testing in temperature-controlled water or saline solution
PID controlled temperature up to 45°C (113°F)
Size is optimized per application
Accompanied by a broad set of accessories that are designed for biomedical baths