(114 days)
TheriFil™ Bone Void Filler is indicated for use in filling the gaps or voids of osseous defects surgically created or resulting from trauma and intended for treatment of osseous defects not intrinsic to the stability of the bone structure. The product is intended for use in defects of the skeletal system (i.e. the extremities, spine and pelvis). TheriFil™ parts create an interlocking network within the defect site that resorbs during healing and is replaced by bone.
The TheriFil™ Bone Void Filler is constructed of synthetic ß-tricalcium phosphate, a commonly found mineral in bone. The porosity and geometric features of B-tricalcium phosphate create an interlocking network within the defect site that resorbs during healing and is replaced by native bone.
Here's an analysis of the provided text regarding the TheriFil™ Bone Void Filler, focusing on the acceptance criteria and the study that proves the device meets those criteria:
The provided document is a 510(k) summary for the TheriFil™ Bone Void Filler, seeking substantial equivalence to predicate devices (Orthovita's Vitoss™ and Wright Medical's WMT-TCP Bone Graft Substitute). It establishes substantial equivalence by comparing technological characteristics and performance in a preclinical animal model.
Here's the breakdown of the requested information:
1. Table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" in the traditional sense of numerical thresholds for clinical performance. Instead, it demonstrates substantial equivalence to a predicate device based on similar technological characteristics and equivalent performance in a preclinical animal model. The "acceptance criteria" can be inferred to be that the TheriFil™ device performs equivalently to the predicate device in the assessed parameters.
| Characteristic | Acceptance Criteria (Implied: Equivalent to Vitoss™) | Reported Device Performance (TheriFil™) |
|---|---|---|
| Porosity | ~80% | ~60% |
| Pore Area (µm²) - Mean | $2700 \pm 2200$ | $3000 \pm 1200$ |
| Pore Area (µm²) - Min | 40 | 40 |
| Pore Area (µm²) - Max | $5.7x10^5 + 3.3x10^5$ | $3.5x10^5 + 2.1x10^5$ |
| Pore Diameter (µm) - Mean | $56 \pm 19$ | $60 \pm 12$ |
| Pore Diameter (µm) - Min | 7 | 7 |
| Pore Diameter (µm) - Max | $810 \pm 270$ | $640 \pm 220$ |
| True Density (grams/mL) | $1.527 \pm 0.002$ | $1.530 \pm 0.001$ |
| Bulk Packing Density (grams/mL) | $0.22 \pm 0.02$ | $0.53 \pm 0.02$ |
| Packing Porosity (%) | $85.8 \pm 1.0$ | $65.7 \pm 1.4$ |
| Pre-clinical performance (tissue reaction, bone ingrowth, residual material, mechanical testing) | Similar to Vitoss™ | Similar to Vitoss™ |
Note: While some physical characteristics show differences (e.g., porosity, bulk packing density, packing porosity), the overall conclusion is that the technological characteristics are "the same or similar" and preclinical performance is "equivalent." The specific numerical bounds for "similar" or "equivalent" are not defined as strict acceptance criteria in this document.
2. Sample size used for the test set and the data provenance
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Physical/Chemical Characteristics (Table 1):
- Sample Size: "n = 30" for SEM images used to estimate porosity and pore area/diameter. For true density, bulk packing density, and packing porosity, sample sizes are not explicitly stated as 'n=30', but derived from methods described in Attachments 13A and 13B.
- Data Provenance: The document does not specify the country of origin. It is a submission to the FDA in the USA. The data would be considered retrospective in the context of this 510(k) submission, as it's data collected to support the submission.
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Pre-clinical Performance Testing:
- Sample Size: Not explicitly stated, but performed "in a canine animal model." The number of animals or implants is not provided.
- Data Provenance: Conducted in a canine animal model. Implied to be retrospective for the submission.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This document does not describe the use of human experts to establish "ground truth" for the test set in the way one might for diagnostic imaging devices. The "ground truth" for the physical characteristics is established by direct measurement (e.g., SEM, pycnometer). For the preclinical animal model, the assessment of tissue reaction, bone ingrowth, residual material, and mechanical testing would typically be performed by veterinary pathologists, researchers, or mechanical engineers with expertise in these areas, but the document does not specify their number or qualifications.
4. Adjudication method for the test set
Not applicable. The data presented are objective measurements and preclinical study results, not subject to human interpretation requiring adjudication in the context of this document.
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 a medical device (bone void filler), not an AI-powered diagnostic tool. Therefore, MRMC studies and "human readers improving with AI assistance" are not relevant to this submission.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
Not applicable. This is a physical medical device, not an algorithm or AI system.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- For physical/chemical characteristics: The ground truth is based on direct physical and chemical measurements (e.g., microscopy for porosity, pycnometry for density).
- For preclinical performance: The ground truth is based on histopathological evaluation (tissue reaction, bone ingrowth, residual material) and mechanical testing in a canine animal model.
8. The sample size for the training set
Not applicable. This is not an AI/machine learning device that requires a "training set." The development of the TheriFil™ device and the selection of its material properties would have been based on scientific understanding of bone biology and material science, but this doesn't constitute a "training set" in the context of an algorithm.
9. How the ground truth for the training set was established
Not applicable, as there is no "training set" in the machine learning sense. The material properties were designed and characterized based on scientific principles and existing knowledge of what constitutes an effective bone void filler, with "ground truth" in this context being established by scientific understanding and experimental validation of material properties and biological response.
§ 888.3045 Resorbable calcium salt bone void filler device.
(a)
Identification. A resorbable calcium salt bone void filler device is a resorbable implant intended to fill bony voids or gaps of the extremities, spine, and pelvis that are caused by trauma or surgery and are not intrinsic to the stability of the bony structure.(b)
Classification. Class II (special controls). The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance: Resorbable Calcium Salt Bone Void Filler Device; Guidance for Industry and FDA.” See § 888.1(e) of this chapter for the availability of this guidance.