(35 days)
The CRESCENT® Spinal System is indicated for interbody fusion with autogenous bone graft in patients with Degenerative Disc Disease (DDD) at one or two contiguous levels from L2 to S1. These DDD patients may also have up to Grade 1 spondylolisthesis or retrolisthesis at the involved levels. DDD is defined as discogenic back pain with degeneration of the disc confirmed by history and radiographic studies. These patients should be skeletally mature and have had six months of non-operative treatment. These devices are intended to be used with supplemental fixation instrumentation which has : been cleared by the FDA for use in the lumbar spine.
The subject CRESCENT® Spinal System consists of a variety of hollow intervertebral body spacers featuring a bullet-nosed, anatomically shaped design with axial voids designed to hold bone graft material. The implants may be implanted via a posterior, transforaminal or lateral approach and the procedure may be open or minimally invasive. The subject devices are designed with diamond V teeth across both superior and inferior surfaces to allow the implant to grip the superior and inferior end plates, thus allowing expulsion resistance. The devices range from 7mm to 15mm in height and 36mm in length. The devices are manufactured from medical grade PEEK-Optima LTI (polyetheretherketone). These devices also contain Tantalum markers used for imaging purposes.
This document describes a 510(k) premarket notification for the CRESCENT® Spinal System. This type of submission focuses on demonstrating "substantial equivalence" to a predicate device rather than presenting new clinical study data with acceptance criteria and a detailed study proving performance. Therefore, many of the requested data points (like sample size for test/training sets, expert qualifications, MRMC studies, standalone performance, and detailed ground truth establishment) are not typically included in such a submission.
However, I can extract the relevant information regarding the "acceptance criteria" and the "study" that supports the substantial equivalence claim.
Here's a breakdown based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
For a 510(k) submission seeking clearance for additional sizes of an existing device, the "acceptance criteria" revolve around demonstrating that the new size does not introduce new safety or effectiveness concerns and performs equivalently to the already cleared predicate.
| Acceptance Criteria Category | Specific Criteria/Tests | Reported Device Performance (Summary) |
|---|---|---|
| Mechanical Performance | Adherence to ASTM F2077 "Test Methods for Intervertebral Body Fusion Devices" for interbody fusion devices. Specifically, ensuring the new size does not represent a "worst-case" scenario for mechanical loads. | The new 14.5mm wide PEEK implant does not introduce a new worst-case scenario compared to the cleared devices. This was supported by a confirmatory engineering rationale. |
| Material Equivalence | The material of construction (PEEK-Optima LTI) must be identical to the predicate device. | The material of the subject CRESCENT® Spinal System implant is identical to the predicate CRESCENT™ Spinal System (K094025). |
| Design Equivalence | Similar design features (hollow intervertebral body spacers, bullet-nosed, anatomically shaped, axial voids for bone graft, diamond V teeth, Tantalum markers). | The subject device features are consistent with the predicate. The submission focuses on adding a new width (14.5mm). |
| Indications for Use Equivalence | The device must share the same indications for use as the predicate devices. | The CRESCENT® Spinal System has the same indications as the predicate devices (K094025 and K110543). |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: Not applicable in the context of a 510(k) for an incremental change like a new size. There isn't a "test set" of patients or images in a clinical efficacy study sense. The "test" here refers to non-clinical, engineering testing and comparison to predicate devices.
- Data Provenance: Not applicable. The "data" comes from engineering analysis and comparison to existing regulatory clearances.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Not applicable. Ground truth for clinical performance is not established for this type of submission. The "ground truth" for substantial equivalence is based on regulatory standards and comparison to previously cleared devices, evaluated by FDA reviewers.
4. Adjudication Method for the Test Set
- Not applicable. No clinical test set requiring adjudication was used.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
- Not applicable. This is not an AI/CAD device. It is a spinal implant.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Not applicable. This is not an AI/CAD device.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
- The "ground truth" in this context is the established safety and effectiveness profile of the predicate devices, as determined by previous FDA clearances. The current submission's "truth" is that the new device variant (14.5mm wide PEEK implant) is equivalent to these predicates and does not introduce new risks. This is supported by:
- Engineering rationale and risk analysis: Demonstrating that the new size does not represent a "worst-case" scenario based on biomechanical principles and ASTM standards.
- Material and design comparison: Verifying identical material and similar design features to the predicate devices.
8. The Sample Size for the Training Set
- Not applicable. There is no "training set" in the context of this 510(k) submission for a spinal implant.
9. How the Ground Truth for the Training Set Was Established
- Not applicable.
Summary of the "Study" Proving Device Meets Acceptance Criteria:
The "study" to prove the device met acceptance criteria was a non-clinical engineering assessment and comparative analysis against legally marketed predicate devices.
- Objective: To demonstrate that the addition of a 14.5mm wide PEEK implant to the CRESCENT® Spinal System is substantially equivalent to previously cleared predicate devices and does not introduce new safety or effectiveness concerns.
- Methodology:
- Identification of Predicates: The subject device was compared to CRESCENT™ Spinal System (K094025) and CRESCENT® Spinal System Titanium (K110543).
- Material Comparison: Verification that the material (PEEK-Optima LTI) is identical to a PEEK predicate (K094025).
- Design Comparison: Analysis of design features of the new 14.5mm wide implant against existing cleared sizes.
- Mechanical Analysis (Worst-Case Assessment): According to the document, ASTM F2077 "Test Methods for Intervertebral Body Fusion Devices" defines a worst-case device. Medtronic argued that since the existing cleared PEEK implants had widths of 11mm, 12mm, and 12.5mm, and the 14.5mm wide Titanium implants were already cleared, the new 14.5mm wide PEEK implant does not introduce a new "worst-case scenario" regarding mechanical performance (as its footprint is not reducing).
- Engineering Rationale and Risk Analysis: A formal engineering justification and risk assessment were completed to support the claim that the new size does not present new risks.
- Conclusion: Based on the engineering rationale, risk analysis, and supporting documentation, Medtronic concluded that the subject system demonstrates substantial equivalence to the listed predicate devices. The FDA concurred, granting clearance.
§ 888.3080 Intervertebral body fusion device.
(a)
Identification. An intervertebral body fusion device is an implanted single or multiple component spinal device made from a variety of materials, including titanium and polymers. The device is inserted into the intervertebral body space of the cervical or lumbosacral spine, and is intended for intervertebral body fusion.(b)
Classification. (1) Class II (special controls) for intervertebral body fusion devices that contain bone grafting material. The special control is the FDA guidance document entitled “Class II Special Controls Guidance Document: Intervertebral Body Fusion Device.” See § 888.1(e) for the availability of this guidance document.(2) Class III (premarket approval) for intervertebral body fusion devices that include any therapeutic biologic (e.g., bone morphogenic protein). Intervertebral body fusion devices that contain any therapeutic biologic require premarket approval.
(c)
Date premarket approval application (PMA) or notice of product development protocol (PDP) is required. Devices described in paragraph (b)(2) of this section shall have an approved PMA or a declared completed PDP in effect before being placed in commercial distribution.