(84 days)
The Suture Welding System and Kit is indicated for securing synthetic monofilament sutures in soft tissues and for securing ligatures of tubular structures wherever conventional monofilament sutures or surgical staples are appropriate. The SWK is indicated for use in both traditional open surgery and endoscopic surgical procedures.
The Axya Suture Welding System and Kit (SWK) is substantially equivalent in design and function to the Axya Suturing and Ligating System (ASLS) and the Endo-Judge disposable suture placement system. Suture applicators and suture placement devices which may be used in both endoscopic or traditional open surgical procedures have been classified under 21 CFR 876.1500. These devices are indicated for the placement of sutures in soft tissue to close either traumatic or surgically produced wounds. The SWK is fabricated from materials with a substantial history of use in medical devices. Both the SWK and the predicate device secure the suture loop with an ultrasonic weld. The ultrasonic energy source used to weld and secure the suture loop is the same generator used for the Automatic Suturing and Ligating System and is similar to the energy source used in the UltraCision Harmonic Scalpel. The suture material is heated and welded by friction and the weld is formed by melting and fusing the polymer. No "flux" or "welding rod" is employed and no new chemical entities are introduced or produced in the welding process. The Axya Suture Welding System and Kit are sterilized by exposure to gamma irradiation at 2.5 Mrads which provides a sterility assurance level of at least 10° or, alternatively, by means of an ethylene oxide gas sterilization process which also provides a SAL of 10°.
Here's an analysis of the provided text regarding the Axya Suture Welding System and Kit (SWK):
Acceptance Criteria and Study Findings for Axya Suture Welding System and Kit (SWK)
The submission highlights the substantial equivalence of the Axya SWK to predicate devices and provides data to support its safety and effectiveness. The acceptance criteria are implicitly derived from the comparisons to established standards (USP requirements) and predicate devices (Axya Suturing and Ligating System (ASLS) and Endo-Judge).
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Suture Strength (Efficacy) | Knot Strength: Equivalent or substantially above USP requirements for respective sizes and types of suture materials. | |
| Holding Strength: Equivalent to sutures placed with conventional knotting techniques. | - Sutures placed by the suture welding process exhibit "knot strength" characteristics substantially above the USP requirements for the respective sizes and types of suture materials tested. |
- Synthetic monofilament sutures placed with the ultrasonic suture welding technology are equivalent in holding strength (efficacy) to sutures placed with conventional knotting techniques.
- Synthetic monofilament sutures secured by weld formed with the AxyaWeld Tips have equivalent knot strength to sutures welded with the predicate AxyaStitch Cartridge. |
| Suture Degradation Profile | Strength Retention: No deleterious effect on the strength retention profile of synthetic absorbable sutures, following the profile described in the suture manufacturer's package insert and exceeding predicted USP requirements. | - Studies on synthetic absorbable sutures (Maxon™) showed strength loss curves following the manufacturer's profile and exceeding predicted USP strength retention requirements. This demonstrates no deleterious effect from the welding process. |
| Safety - Tissue Reaction | Histopathologic Change: No significant difference in safety or efficacy in terms of tissue reaction between welded sutures and manually knotted sutures. No histopathologic change at implant sites. | - In animal models (New Zealand rabbits, dorsal skin and bowel tissue), there was no histopathologic change seen at the suture implant sites where the suture was sealed with ultrasonic energy. - Investigators concluded no significant difference in safety or efficacy between traditional knotting and suture welding. |
| Safety - Thermal Injury | Minimal to virtually no risk of thermal injury to the patient. | - No portion of the ultrasonic generator comes into contact with human tissues. - The design of the AxyaWeld Sleeve prevents the heated area of suture from coming into direct contact with tissues. |
| Sterility | Achievable sterility assurance level (SAL) of at least 10⁻⁶ via gamma irradiation or ethylene oxide gas sterilization. Sterility processes, manufacturing, and packaging are validated. | - Sterilized by exposure to gamma irradiation at 2.5 Mrads (SAL of at least 10⁻⁶) or ethylene oxide gas sterilization (SAL of 10⁻⁶). - Sterility processes, manufacturing, and packaging processes are validated by the manufacturer. |
| Biocompatibility | Fabricated from materials with a substantial history of use in medical devices and thoroughly tested in accordance with applicable FDA guidelines. No new chemical entities introduced or produced during welding. | - Fabricated from materials with a substantial history of use in medical devices. - Specific materials used by Axya have been thoroughly tested in accordance with applicable FDA guidelines.
- No "flux" or "welding rod" is employed and no new chemical entities are introduced or produced in the welding process. |
2. Sample Size Used for the Test Set and Data Provenance
The provided text describes the studies as "previously submitted efficacy studies" and "in vivo and in vitro studies." However, the exact sample sizes for the test sets (e.g., number of suture samples for strength, number of animals for in vivo studies) are not specified in this document.
Regarding data provenance:
- Country of Origin: Not specified.
- Retrospective or Prospective: Not explicitly stated, but the description of the studies (e.g., "Maxon™...tested for strength at baseline and at one-week intervals over seven weeks") suggests a prospective experimental design for the in vitro strength retention studies. The animal studies would also be prospective.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
The text mentions "The investigators concluded that there was no significant difference in safety of efficacy..." in the context of the animal studies. However, the number of experts (investigators) involved in establishing the ground truth (e.g., assessing histopathologic change) is not specified. Their specific qualifications (e.g., board-certified veterinary pathologists, surgeons with X years of experience) are also not detailed.
4. Adjudication Method for the Test Set
The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for resolving discrepancies in ground truth establishment for the test sets. The mention of "investigators concluded" suggests a consensus or lead investigator's finding, but the process is not elaborated.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not explicitly mentioned or described in the provided text. The studies focus on comparing the device's performance to predicate devices and conventional techniques, but not specifically on how human readers/surgeons' effectiveness might improve with or without AI assistance (as this is not an AI device).
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was Done
This device is not an AI algorithm. It is a surgical tool. Therefore, the concept of "standalone (algorithm only)" performance without human-in-the-loop is not applicable. The device inherently requires a human operator for its function.
7. The Type of Ground Truth Used
The ground truth used in the studies appears to be a combination of:
- Performance Benchmarks/Standards: USP requirements for knot strength and strength retention.
- Direct Comparison to Predicate Devices: E.g., AxyaStitch Cartridge for knot strength.
- Direct Comparison to Conventional Techniques: Conventional knotting techniques for holding strength and manual knotting for safety/efficacy in animal models.
- Histopathology: In the animal studies, histopathologic examination of tissue samples at implant sites, likely interpreted by pathologists.
8. The Sample Size for the Training Set
The devices described are not AI/ML algorithms that utilize a "training set" in the conventional sense. Therefore, the concept of a "training set sample size" is not applicable. The studies described are validation studies for a physical medical device.
9. How the Ground Truth for the Training Set Was Established
As explained above, the concept of a "training set" and its associated ground truth establishment is not applicable to this type of medical device submission.
§ 878.5010 Nonabsorbable polypropylene surgical suture.
(a)
Identification. Nonabsorbable polypropylene surgical suture is a monofilament, nonabsorbable, sterile, flexible thread prepared from long-chain polyolefin polymer known as polypropylene and is indicated for use in soft tissue approximation. The polypropylene surgical suture meets United States Pharmacopeia (U.S.P.) requirements as described in the U.S.P. Monograph for Nonabsorbable Surgical Sutures; it may be undyed or dyed with an FDA approved color additive; and the suture may be provided with or without a standard needle attached.(b)
Classification. Class II (special controls). The special control for this device is FDA's “Class II Special Controls Guidance Document: Surgical Sutures; Guidance for Industry and FDA.” See § 878.1(e) for the availability of this guidance document.