By Steve Twork
Can canted coil springs meet FDA regulatory requirements or OEM cleaning validation standards?
This question was posed by a client when we recommended using our spring technology in orthopedic surgical instruments. Typically, OEMs validate and verify components during feasibility testing, but feasibility failures can add cost and offset your project timeline. Advanced test data on components not only helps avoid such feasibility failures, but also speeds development time. We conducted this advanced testing to help OEMs ensure that their medical device development projects stay on track. Materials and Methods For testing, we selected commonly used orthopedic devices that use a single housing with multiple groove configurations consisting of a Bal Seal Canted Coil Spring (BSE 100 series) in each groove (see Figure 1).
Materials and Methods
For testing, we selected commonly used orthopedic devices that use a single housing with multiple groove configurations consisting of a Bal Seal Canted Coil Spring (BSE 100 series) in each groove (see Figure 1).
Test Procedure: The cleaning validation was performed in accordance with the AAMI TIR30:2011 guidance document, “A compendium of processes, materials, test methods, and acceptance criteria for cleaning reusable medical devices.” The following protocols were used:
• Standard Test Protocol (STP) Number: STP0083 Rev. 10
• Protocol Detail Sheet (PDS) Number: 201305677 Rev.01
Test Soil: Defibrinated blood soil (DBLSO)
Cleaning Method: Manual
Residuals Tested: Hemoglobin and protein
The devices were fully immersed in prepared blood soil. The devices were allowed to remain in contact with the prepared blood soil for a minimum of 15 minutes. After the 15-minute contact time, the devices were removed from the prepared blood soil and allowed to dry uncovered at room temperature for a minimum of one hour.
Hemoglobin Test: The limit of detection (LOD) for the method was calculated to be 0.16 µg/mL. This value was used in the calculations for test devices with results below the detection limit. The limit of quantitation (LOQ) for the method was calculated to be 0.5 µg/mL. In cases in which the µg/mL value was between the LOD and LOQ, the calculated results were estimated. The hemoglobin concentrations shown are the average of the three replicates. See actual data results in Table I.
| Article Number | µg/mL | µg/article | µg/cm² |
|---|---|---|---|
| 1 | Ë‚0.16 | Ë‚3.2 | Ë‚0.37 |
| 2 | 0.18 | 3.6 | 0.42 |
| 3 | 0.34 | 6.8 | 0.79 |
| Negative article | 1.3 | 25 | 2.9 |
| Positive article | 2.4 | 4,800 | 560 |
Micro BCA™ Protein Test: The LOD for the assay was calculated to be 1.1 µg/mL. This value was used in the calculations for test devices for which the absorbance was below the detection limit. The LOQ for the assay was calculated to be 2.0 µg/mL. In cases in which the µg/mL value was between the LOD and the LOQ, the calculated results were estimated (see Table II).
| Article Number | µg/mL | µg/article | µg/cm² |
|---|---|---|---|
| 1 | Ë‚1.1 | Ë‚2.2 | Ë‚2.6 |
| 2 | Ë‚1.1 | <22 | Ë‚2.6 |
| 3 | 2.3 | 46 | 5.3 |
| Negative article | 1.4 | 28 | 3.2 |
| Positive article | 590 | 12,000 | 1,400 |
Results and Discussion
Following the cleaning procedure, no soil was seen on the processed test devices under normal lighting conditions during visual inspection. Such testing enables OEMs to validate and verify components more quickly and easily. Because feasibility failures can add cost and time to development, advanced test data on components can help keep development on time and on budget.
