(139 days)
The AcroMed 4.75 mm Pedicle Screw is designed to be utilized with the VSP Spinal Fixation System. The VSP Spinal Fixation System is intended for use in grade 3 or 4 spondylolisthesis at LS-S1, utilizing autologous bone graft, having the device fixed or attached to the lumbar or sacral spine and intended to be removed after solid fusion is attained. Levels of attachment for this indication range from L3 to the sacrum.
The AcroMed Pedicle Screw is composed of two sections: a long cancellous section with an integral fixed lower nut, and a machine threaded section topped with an hexagonal drive head. The integral nut serves two purposes: it creates a stronger bolt connection between the screw and plate and it eliminates the "claw hammer" effect associated with other screw designs. The upper surface of the integral nut is a transverse flat smooth surface to provide maximum contact area with the underside of the VSP spine plate.
The AcroMed Pedicle Screw is supplied with an adjustable tapered nut and an optional lock nut, which enables a pedicle screw and a slotted connector to be adjoined utilizing a locking nut system. The junction point of the adjustable integral nut and machine thread portion of the pedicle screw is also rounded to reduce potential stress concentration.
The screw is available in cancellous thread lengths from 25 mm to 50 mm, in 5 mm increments.
The AcroMed Pedicle Screw is manufactured from implant grade stainless steel conforming to ASTM F1314 specifications.
Here's an analysis of the provided text regarding acceptance criteria and study information for the AcroMed Pedicle Screw (4.75 mm):
The provided text ("K965102") describes a 510(k) summary for the AcroMed Pedicle Screw. However, it does not contain the detailed information requested regarding specific acceptance criteria, performance metrics (like sensitivity, specificity, AUC), study methodology, data provenance, ground truth establishment, or human reader studies.
The document is a regulatory submission demonstrating substantial equivalence to a previously cleared device, focusing on material, design, and intended use.
Here's a breakdown of what can be extracted and what is missing:
The core of the "Performance Data" section states: "Static and fatigue testing show the AcroMed pedicle screws (4.75 mm) to perform consistently with previously cleared components." This implies that the acceptance criteria for this device are met if its static and fatigue performance is consistent with a predicate device (cleared under K951116).
Here's the table based on the provided input, with many fields marked as "Not provided in the text" due to the nature of the document:
| Aspect | Information Provided |
|---|---|
| 1. Acceptance Criteria and Reported Device Performance | |
| Acceptance Criteria | "Perform consistently with previously cleared components" (specifically regarding static and fatigue testing). |
| Reported Device Performance | "Static and fatigue testing show the AcroMed pedicle screws (4.75 mm) to perform consistently with previously cleared components." |
| 2. Sample size used for the test set and data provenance | Not provided in the text. This type of detail would be in a full testing report, not a 510(k) summary. |
| 3. Number of experts used to establish ground truth for the test set and qualifications | Not applicable. This document refers to mechanical testing, not a clinical study involving human experts for "ground truth" in the diagnostic sense. |
| 4. Adjudication method for the test set | Not applicable (mechanical testing). |
| 5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done | No. This is a medical device for implantation, not an AI or diagnostic imaging device that would typically undergo an MRMC study. |
| 6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done | Not applicable. This is a physical medical device. The "standalone" concept usually applies to AI algorithms. |
| 7. The type of ground truth used | For mechanical testing, the "ground truth" would be established engineering standards, material properties, and comparative performance data of the predicate device. Specific methodologies are not detailed. |
| 8. The sample size for the training set | Not applicable. This refers to the manufacturing and testing of a physical product, not an AI model. |
| 9. How the ground truth for the training set was established | Not applicable. |
Summary of Missing Information and Why:
The provided document is a 510(k) summary for a physical medical device (pedicle screw). It primarily focuses on demonstrating "substantial equivalence" to a predicate device. For such devices, the performance data typically involves:
- Mechanical Testing: Static (e.g., yield strength, ultimate tensile strength) and fatigue (e.g., ability to withstand repeated loads without failure) tests.
- Biocompatibility Testing: Ensuring the material is safe for implantation.
- Sterilization Validation: Ensuring the device can be properly sterilized.
The questions you've asked (about sensitivity, specificity, AUC, expert consensus, MRMC studies, AI training sets, etc.) are highly relevant for diagnostic imaging devices or AI/CAD systems, which often involve interpreting medical images or data. They are not typically applicable to a device like a pedicle screw, where "performance" is measured in terms of mechanical integrity and biological compatibility.
To address your questions fully for this type of device, you would need to examine the full submission, which would include detailed test protocols, results, and standards referenced for the static and fatigue testing.
§ 888.3070 Thoracolumbosacral pedicle screw system.
(a)
Identification. (1) Rigid pedicle screw systems are comprised of multiple components, made from a variety of materials that allow the surgeon to build an implant system to fit the patient's anatomical and physiological requirements. Such a spinal implant assembly consists of a combination of screws, longitudinal members (e.g., plates, rods including dual diameter rods, plate/rod combinations), transverse or cross connectors, and interconnection mechanisms (e.g., rod-to-rod connectors, offset connectors).(2) Semi-rigid systems are defined as systems that contain one or more of the following features (including but not limited to): Non-uniform longitudinal elements, or features that allow more motion or flexibility compared to rigid systems.
(b)
Classification. (1) Class II (special controls), when intended to provide immobilization and stabilization of spinal segments in skeletally mature patients as an adjunct to fusion in the treatment of the following acute and chronic instabilities or deformities of the thoracic, lumbar, and sacral spine: severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra; degenerative spondylolisthesis with objective evidence of neurologic impairment; fracture; dislocation; scoliosis; kyphosis; spinal tumor; and failed previous fusion (pseudarthrosis). These pedicle screw spinal systems must comply with the following special controls:(i) Compliance with material standards;
(ii) Compliance with mechanical testing standards;
(iii) Compliance with biocompatibility standards; and
(iv) Labeling that contains these two statements in addition to other appropriate labeling information:
“Warning: The safety and effectiveness of pedicle screw spinal systems have been established only for spinal conditions with significant mechanical instability or deformity requiring fusion with instrumentation. These conditions are significant mechanical instability or deformity of the thoracic, lumbar, and sacral spine secondary to severe spondylolisthesis (grades 3 and 4) of the L5-S1 vertebra, degenerative spondylolisthesis with objective evidence of neurologic impairment, fracture, dislocation, scoliosis, kyphosis, spinal tumor, and failed previous fusion (pseudarthrosis). The safety and effectiveness of these devices for any other conditions are unknown.”
“Precaution: The implantation of pedicle screw spinal systems should be performed only by experienced spinal surgeons with specific training in the use of this pedicle screw spinal system because this is a technically demanding procedure presenting a risk of serious injury to the patient.”
(2) Class II (special controls), when a rigid pedicle screw system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion in the treatment of degenerative disc disease and spondylolisthesis other than either severe spondylolisthesis (grades 3 and 4) at L5-S1 or degenerative spondylolisthesis with objective evidence of neurologic impairment. These pedicle screw systems must comply with the following special controls:
(i) The design characteristics of the device, including engineering schematics, must ensure that the geometry and material composition are consistent with the intended use.
(ii) Non-clinical performance testing must demonstrate the mechanical function and durability of the implant.
(iii) Device components must be demonstrated to be biocompatible.
(iv) Validation testing must demonstrate the cleanliness and sterility of, or the ability to clean and sterilize, the device components and device-specific instruments.
(v) Labeling must include the following:
(A) A clear description of the technological features of the device including identification of device materials and the principles of device operation;
(B) Intended use and indications for use, including levels of fixation;
(C) Identification of magnetic resonance (MR) compatibility status;
(D) Cleaning and sterilization instructions for devices and instruments that are provided non-sterile to the end user; and
(E) Detailed instructions of each surgical step, including device removal.
(3) Class II (special controls), when a semi-rigid system is intended to provide immobilization and stabilization of spinal segments in the thoracic, lumbar, and sacral spine as an adjunct to fusion for any indication. In addition to complying with the special controls in paragraphs (b)(2)(i) through (v) of this section, these pedicle screw systems must comply with the following special controls:
(i) Demonstration that clinical performance characteristics of the device support the intended use of the product, including assessment of fusion compared to a clinically acceptable fusion rate.
(ii) Semi-rigid systems marketed prior to the effective date of this reclassification must submit an amendment to their previously cleared premarket notification (510(k)) demonstrating compliance with the special controls in paragraphs (b)(2)(i) through (v) and paragraph (b)(3)(i) of this section.