ACROMED PEDICLE SCREW
Device Facts
| Record ID | K965102 |
|---|---|
| Device Name | ACROMED PEDICLE SCREW |
| Applicant | Acromed Corp. |
| Product Code | MNH · Orthopedic |
| Decision Date | May 8, 1997 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 888.3070 |
| Device Class | Class 2 |
| Attributes | Therapeutic |
Intended Use
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 L5-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.
Device Story
Pedicle screw component of VSP Spinal Fixation System; two-section design: long cancellous section with integral fixed lower nut and machine-threaded section with hexagonal drive head. Integral nut provides contact area for VSP spine plate; rounded junction reduces stress concentration. Supplied with adjustable tapered nut and optional lock nut for slotted connector attachment. Used by surgeons in spinal fusion procedures; provides mechanical stabilization of lumbar/sacral spine segments. Benefits patient by maintaining alignment during bone graft fusion process; removed after fusion achieved.
Clinical Evidence
Bench testing only. Static and fatigue testing performed to demonstrate equivalence to previously cleared components.
Technological Characteristics
Implant grade stainless steel per ASTM F1314. Dimensions: 4.75 mm diameter; cancellous thread lengths 25-50 mm in 5 mm increments. Mechanical fixation via integral nut, adjustable tapered nut, and optional lock nut.
Indications for Use
Indicated for patients with grade 3 or 4 spondylolisthesis at L5-S1 requiring spinal fixation with autologous bone graft; attachment levels L3 to sacrum; intended for removal post-fusion.
Regulatory Classification
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.
Special Controls
*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.
Predicate Devices
- AcroMed pedicle screws (K951116)
Related Devices
- K040493 — OUTOLOGOUS SPINAL FIXATION SYSTEM · Orthopedic Sciences, Inc. · Sep 3, 2004
- K963639 — ACROMED PEDICLE SCREW · Acromed Corp. · Nov 14, 1996
- K103383 — SPARTEK VARIABLE ANGLE PEDICLE SCREW POSTERIOR FUSION SYSTEM · Spartek Medical, Inc. · Feb 17, 2011
- K965046 — ISOLA TWISTER CONNECTOR · Acromed Corp. · Mar 14, 1997
- K142737 — MAS PLIF Fixation system · Nu Vasive, Incorporated · Dec 18, 2014
