A construct with screws attached to the pedicles of the lumbar and sacral spine (L3 to S1) and autogenous bone graft may be used only for the treatment of severe spondylolisthesis (Grade 3 and Grade 4) at the fifth lumbar - first sacral (L5-S1) vertebral joint (see warnings below). The device is intended to be implanted using a posterior surgical approach and removed after the development of a solid fusion mass. When not used as a pedicle screw fixation system, various combinations of the Titanium Versalok Screw Assembly components are also indicated to provide temporary stability of the thoracic, thoracolumbar, or lumbar spine (T1 to S1) during bony fusion healing secondary to: 1. Unstable spinal fractures (such as fracture dislocations) or instability secondary to spinal tumors; 2. Degenerative disk diseases of the spine (defined as back pain of diskogenic origin with degeneration of the disk confirmed by radiographic studies); 3. Spinal curvatures (such as idiopathic scoliosis, neuromuscular scoliosis/kyphoscoliosis with associated paralysis or spasticity, and secondary to spinal fractures) which are: Progressive, despite other forms of treatment, Detrimental to cardiopulmonary function, Interfering with spinal mechanics or causing severe back pain, or Cosmetically unacceptable, progressive, and painful. The system is intended to provide temporary maintenance and support of the correction during the time normally needed for the fusion mass to mature. Use of spinal fixation instrumentation in children has been reported. Children should have adequate bony and soft tissue maturity to undergo implantation but need not have reached skeletal maturity.
Device Story
Titanium Versalok Screw Assembly is a spinal fixation system consisting of straight rods, outer rings, caps, and polyaxial screws. Implanted via posterior surgical approach by surgeons to provide temporary spinal stability during bony fusion healing. Device supports spine in cases of fractures, tumors, degenerative disk disease, or spinal curvatures. Once solid fusion occurs, device is intended for removal. Provides mechanical maintenance and support of spinal correction during fusion mass maturation.
Clinical Evidence
No clinical data provided; substantial equivalence supported by mechanical test data.
Technological Characteristics
Titanium spinal fixation system; components include straight rods, outer rings, caps, and polyaxial screws. Designed for posterior implantation. Mechanical stabilization principle.
Indications for Use
Indicated for patients requiring spinal stabilization for severe spondylolisthesis (Grade 3-4 at L5-S1), unstable spinal fractures, spinal tumors, degenerative disk disease, or spinal curvatures (scoliosis/kyphoscoliosis). Applicable to thoracic, thoracolumbar, and lumbar spine (T1-S1). Suitable for children with adequate bony/soft tissue maturity.
Regulatory Classification
Identification
A spinal interlaminal fixation orthosis is a device intended to be implanted made of an alloy, such as stainless steel, that consists of various hooks and a posteriorly placed compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The device is used primarily in the treatment of scoliosis (a lateral curvature of the spine), but it also may be used in the treatment of fracture or dislocation of the spine, grades 3 and 4 of spondylolisthesis (a dislocation of the spinal column), and lower back syndrome.
Predicate Devices
Versalok Screw Assembly
Submission Summary (Full Text)
{0}------------------------------------------------
3/30/99
## Attachment 7
Summary
# K990708 510(k) Summary
Company: Wright Medical Technology, Inc. 5677 Airline Road Arlington, TN 38002 Date: March 3, 1999 Trade Name: Titanium Versalok Screw Assembly Common Name: Spondylolisthesis Spinal Fixation Device System Predicate Device: Versalok Screw Assembly
Description/Intended Use: The Titanium Versalok Screw Assembly consists of straight rods, an outer ring, cap, and polyaxial screws, and the instruments necessary to implant this specific system. The Titanium Versalok Screw Assembly is intended to provide stabilization of the spine for various indications (see below). The device is intended to be removed after solid fusion has occurred.
A construct with screws attached to the pedicles of the lumbar and sacral spine (L3 to S1) and autogenous bone graft may be used only for the treatment of severe spondylolisthesis (Grade 3 and Grade 4) at the fifth lumbar - first sacral (LS-S1) vertebral joint (see warnings below). The device is intended to be implanted using a posterior surgical approach and removed after the development of a solid fusion mass.
When not used as a pedicle screw fixation system, various combinations of the Titanium Versalok Screw Assembly components are also indicated to provide temporary stability of the thoracic, thoracolumbar, or lumbar spine (T1 to S1) during bony fusion healing secondary to:
- Unstable spinal fractures (such as fracture dislocations) or instability 1. secondary to spinal tumors:
- 2. Degenerative disk diseases of the spine (defined as back pain of diskogenic origin with degeneration of the disk confirmed by radiographic studies):
- Spinal curvatures (such as idiopathic scoliosis, neuromuscular 3. scoliosis/kyphoscoliosis with associated paralysis or spasticity, and secondary to spinal fractures) which are:
- · Progressive, despite other forms of treatment.
- · Detrimental to cardiopulmonary function,
- · Interfering with spinal mechanics or causing severe back pain,
- or
- · Cosmetically unacceptable, progressive, and painful.
The system is intended to provide temporary maintenance and support of the correction during the time normally needed for the fusion mass to mature. Use of spinal fixation instrumentation in children has been reported. Children should have adequate bony and soft tissue maturity to undergo implantation but need not have reached skeletal maturity.
The Titanium Versalok Screw Assembly was declared substantially equivalent to other predicate or preamendment devices. Mechanical test data was provided in the application.
{1}------------------------------------------------
Image /page/1/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized symbol featuring three abstract human profiles facing to the right, stacked on top of each other.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
MAR 3 0 1999
Mr. Dan Regan Director, Clinical and Requlatory Affairs Wright Medical Technology, Inc. 5677 Airline Road 38002 Arlington, Tennessee
K990708 Re: Titanium Versalok Screw Assembly Trade Name: Requlatory Class: II Product Codes: KWP and MNH Dated: March 3, 1999 March 4, 1999 Received:
Dear Mr. Regan:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Requlations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, as set forth in the Quality System Regulation (QS) for Medical Devices: General requlation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP requlation may result in requlatory action. In addition, FDA may publish further announcements concerning your device in the Federal Reqister. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
{2}------------------------------------------------
#### Page 2 - Mr. Dan Regan
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to the regulation entification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".
Sincerely yours,
Celia M. Witten, Ph.D., M.D. Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
{3}------------------------------------------------
# Attachment 3
í
# Indications for Use Statement
## 510(k) Number (if known)
| Device Name | Titanium Versalok |
|---------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Indications for Use | A construct with screws attached to the pedicles of the lumbar and sacral spine (L3 to S1) and autogenous bone graft may be used only for the treatment of severe spondylolisthesis (Grade 3 and Grade 4) at the fifth lumbar - first sacral (L5-S1) vertebral joint (see warnings below). The device is intended to be implanted using a posterior surgical approach and removed after the development of a solid fusion mass. |
| | When not used as a pedicle screw fixation system, various combinations of the Titanium Versalok Screw Assembly components are also indicated to provide temporary stability of the thoracic, thoracolumbar, or lumbar spine (T1 to S1) during bony fusion healing secondary to: |
| | 1. Unstable spinal fractures (such as fracture dislocations) or instability secondary to spinal tumors; |
| | 2. Degenerative disk diseases of the spine (defined as back pain of diskogenic origin with degeneration of the disk confirmed by radiographic studies); |
| | 3. Spinal curvatures (such as idiopathic scoliosis, neuromuscular scoliosis/kyphoscoliosis with associated paralysis or spasticity, and secondary to spinal fractures) which are: |
| | <ul><li>Progressive, despite other forms of treatment,</li><li>Detrimental to cardiopulmonary function,</li><li>Interfering with spinal mechanics or causing severe back pain,</li><li>Cosmetically unacceptable, progressive, and painful.</li></ul> |
| | The system is intended to provide temporary maintenance and support of the correction during the time normally needed for the fusion mass to mature. Use of spinal fixation instrumentation in children has been reported. Children should have adequate bony and soft tissue maturity to undergo implantation but need not have reached skeletal maturity. |
| | PLEASE DO NOT WRITE BELOW THIS LINE- CONTINUE ON ANOTHER PAGE IF NEEDED |
| | Concurrence of CDRH, Office of Device Evaluation (ODE) |
(Division Sign-Off)
Division of General Restorative Devices
510(k) Number. K990208
Prescription Use
X
(per 21 CFR 801.109)
OR
Over-The Counter Use _________________________________________________________________________________________________________________________________________________________
00028
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Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
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Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.
