(283 days)
The disposable hypodermic monopolar needles are FOR SINGLE USE ONLY in electromyography (EMG) in situations wherein it is desired to insert an electrode, in the form of a probe, into a patient to locate a particular muscle and then inject a medication into that muscle. The hypodermic needle with an open lumen is designed for muscle stimulation, motor unit action potential recording and drug delivery. Once the physician is satisfied with the location, he/she injects a drug therein via the lumen of the needle.
The Myoject™ Luer Lock Needle Electrode is a Disposable Hypodermic Needle Electrode
Here's a breakdown of the acceptance criteria and the study information for the Natus Manufacturing Limited Myoject™ Luer Lock Needle Electrode, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
The document primarily focuses on demonstrating substantial equivalence to a predicate device (Teca Myoject Disposable Needle Electrode K973444) through a comparison of characteristics and performance testing. There isn't a direct "acceptance criteria" table with specific pass/fail metrics explicitly stated alongside the new device's performance in a quantitative manner for most characteristics. Instead, the "Discussion of Differences" column in Table 5A (starting on page 5) serves as the primary mechanism for demonstrating equivalence and addressing performance.
However, for Biocompatibility and Bench Testing, the performance is reported against established ISO and ASTM standards.
| Characteristic / Test | Acceptance Criteria (Implicit from Predicate/Standards) | Myoject™ Luer Lock Needle Electrode Performance (Reported) |
|---|---|---|
| Biocompatibility | ||
| Cytotoxicity | Non-cytotoxic (ISO 10993-5:2009) | Non-cytotoxic to L929 cells |
| Irritation (Intracutaneous) | Average reaction not greater than control (ISO 10993-10:2010) | Meets requirements; average reaction not greater than control for polar and non-polar extracts |
| Sensitization (Local Lymph Node Assay) | Non-sensitizer (ISO 10993-10:2010) | Polar and non-polar extracts considered non-sensitizers. Positive controls gave SI > 3 (as expected for positive control function). |
| Systemic Toxicity | PASS (ISO 10993-11:2006) | 0.9% sodium chloride solution extract: PASS; Cottonseed oil extract: PASS |
| Bench Testing | ||
| Tensile testing | Implied to meet design specifications | Conducted; meets performance and design specifications |
| Coating thickness | Implied to meet design specifications | Conducted; meets performance and design specifications |
| Leak Testing | Implied to meet design specifications | Conducted; meets performance and design specifications |
| Tip geometry grind measurements | Implied to meet design specifications | Conducted; meets performance and design specifications |
| Penetration testing | Reduced initial penetration force compared to predicate (discussed as an improvement) | Conducted; meets performance and design specifications. Implied improved penetration. |
| Luer Lock Design Verification | Secure Luer Lock connection (reduced seepage/leakage) | Conducted; meets performance and design specifications. Luer lock is described as adding an additional safety mechanism. |
| Other Comparisons (from Table 5A) | ||
| Labelling | Equivalent, with minor changes not affecting safety/effectiveness | Minor changes (manufacturer name, address, branding, warnings, harmonized symbols); do not raise questions of safety/effectiveness. |
| Intended Use | Same as predicate | Same as predicate; minor labeling nuance regarding drug supply does not affect safety/effectiveness. |
| Physical Characteristics | Monopolar Needle | Same |
| Connector | Single Contact Touch Proof DIN42 802 | Same |
| Material of Needle | Stainless 304 | Same |
| Needle Diameter (mm) | 0.30, 0.41, 0.46, 0.51, 0.71 | Same |
| Needle Coating Material | PTFE (different formulation) | PTFE (Xylan 8820 G4075); improved to reduce initial penetration force, similar safety/effectiveness. |
| Hub | Luer Slip (predicate) | Luer Lock/Slip; improved to reduce risk of medication leakage. Doesn't affect overall function/safety/effectiveness. |
| Hub Material | Polycarbonate (predicate) | Polypropylene (Exxonmobil) Escorene PP9074 MED; equivalent material performance, no new safety/effectiveness concerns. |
| Needle grind angle | 10-20 degrees conical (predicate) | 10-16 degrees conical; slight change in upper range, not significant, no new safety/effectiveness concerns, no altered diagnostic effects. |
| Recording area (sqmm) | 0.25 (predicate) | 0.19 (fine) to 0.89 (depending on size); differences vary, no effect on safety/effectiveness or diagnostic effects. |
| Length (mm) | 25, 37, 50, 75, 100 (predicate) | 25, 37, 50, 75; 100mm version obsolete. No new safety/effectiveness concerns. |
| Connecting lead | 14 or 26 inches, 2mm or touchproof plug (predicate) | 770±10mm, 'ST' moulded 1.5mm touch proof. Cable length "30" (76cm) to 1.5mm female touchproof connector; increased length, minor changes, no new safety/effectiveness concerns. |
| Sterilization | Supplied sterilized gamma irradiated | Same |
| Protective Sheath | Polyethylene (predicate) | Polypropylene Escorene PP9074 MED (Exxon Mobil); equivalent material performance, no new safety/effectiveness concerns. |
| Protective Pouch | Tyvek/Mylar | Same |
| Sterility Assurance Level (SAL) | 10 minus 6 (predicate) | 10 minus 6; improved needle tip sharpness. No new safety/effectiveness concerns. |
| Tip geometry | Lancet Point (predicate) | Trocar Point, 15 degree bevel; preferred for range of needles, improves tip sharpness, reduces patient discomfort. |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size for Test Set: The document does not explicitly state specific sample sizes for each of the performance tests (tensile, coating thickness, leak, tip geometry, penetration, Luer Lock verification). It refers to "Performance Testing" and "Bench Testing" being performed. For biocompatibility tests, details are provided on the methods (e.g., L929 cells for cytotoxicity, rabbit for intracutaneous reactivity, mouse for local lymph node assay), but the exact number of test items or animals used is not specified in this summary.
- Data Provenance: The studies were conducted by Natus Manufacturing Limited, which is based in Ireland. The nature of these tests (biocompatibility, bench testing) usually implies controlled laboratory settings rather than patient data. Therefore, the data Provenance is the manufacturer's internal testing. Not retrospective or prospective patient data.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications:
- This is not applicable as the studies described are non-clinical performance tests (biocompatibility and bench testing) and technical comparisons to a predicate device. The "ground truth" is established by adherence to recognized international standards (ISO, ASTM) for materials, design, and manufacturing quality, not expert consensus on clinical cases.
4. Adjudication Method for the Test Set:
- Not applicable, as this refers to non-clinical performance and design verification tests, not clinical studies with human assessors.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
- No, an MRMC comparative effectiveness study was not done. This device is a diagnostic electromyograph needle electrode, not an image-based diagnostic AI device that would typically involve an MRMC study. The comparison is primarily against a predicate device's design specifications and performance standards through bench testing.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
- Not applicable. This device is a medical instrument (needle electrode), not an algorithm or AI system.
7. The Type of Ground Truth Used:
- The "ground truth" for demonstrating the device's acceptable performance and substantial equivalence is based on:
- Adherence to International Standards: ISO 10993 series (Biocompatibility), ISO 2859-1 (Sampling), ASTM F 1980 (Sterile Barrier).
- Predicate Device Specifications: The Teca Myoject Disposable Needle Electrode (K973444) serves as the primary benchmark for comparison of design and technological characteristics.
- Design and Performance Specifications: The device's own predetermined specifications for physical characteristics and functional performance (e.g., tensile strength, leak integrity, penetration force).
8. The Sample Size for the Training Set:
- Not applicable. There is no training set mentioned, as this is a physical medical device, not an AI or machine learning model.
9. How the Ground Truth for the Training Set Was Established:
- Not applicable, as there is no training set.
§ 890.1385 Diagnostic electromyograph needle electrode.
(a)
Identification. A diagnostic electromyograph needle electrode is a monopolar or bipolar needle intended to be inserted into muscle or nerve tissue to sense bioelectrical signals. The device is intended for medical purposes for use in connection with electromyography (recording the intrinsic electrical properties of skeletal muscle).(b)
Classification. Class II (performance standards).