The Inter-Os Limb Lengthener is an implantable device for distraction osteogenesis techniques in the femur. The Inter-Os Limb Lengthener is used to treat conditions for limb length deficiencies involving the femur. The types of deformities that fall into this category are: Traumatic deformities, growth deformities, deformities secondary to tumors and infections, and congenital deformities. The Inter-Os Limb Lengthener is intended to be used in the upper leg bones of the appendicular skeleton. The Limb Lengthener is not intended to be used for the spine. The Inter-Os Limb Lengthener is intended for single use and is not meant for repeat sterilization and implantation. The device is to be removed after consolidation of the bone is complete. It is to be used with other commercially-available accessory devices, such as bone screws for fixation to the bone surface. Bone cement is not to be used to fixate the device to the bone; however, commercially-available bone cement may be used on the undersurface of the device to level or stabilize it on a curved surface, or bone cement may also be used to fix the gear in position during the consolidation period.
Device Story
Implantable bone fixation device for distraction osteogenesis in femur; treats limb length deficiencies. Device consists of two telescoping bone plates distracted by a threaded drive shaft; internal gear mechanism activated via transcutaneous pin. Orthopedic surgeons implant device; pin removed post-distraction; device removed after bone consolidation. Used with accessory bone screws; bone cement may stabilize device or gear. Provides mechanical distraction to stimulate bone growth; benefits patients with limb length discrepancies.
Clinical Evidence
Bench testing only; mechanical tests performed in conformity to standard testing guidelines for equivalent devices, supplemented by literature review.
Technological Characteristics
Stainless steel construction; telescoping bone plates with threaded drive shaft and internal gear; transcutaneous pin activation; single-use; non-sterile; intended for femoral implantation.
Indications for Use
Indicated for distraction osteogenesis in the femur to treat limb length deficiencies resulting from traumatic, growth, tumor-related, infectious, or congenital deformities in the upper leg bones of the appendicular skeleton. Not for use in the spine.
Regulatory Classification
Identification
Single/multiple component metallic bone fixation appliances and accessories are devices intended to be implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a plate, a nail/plate combination, or a blade/plate combination that are made of alloys, such as cobalt-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners, such as screws and nails, or bolts, nuts, and washers. These devices are used for fixation of fractures of the proximal or distal end of long bones, such as intracapsular, intertrochanteric, intercervical, supracondylar, or condylar fractures of the femur; for fusion of a joint; or for surgical procedures that involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force (traction) may be applied to the skeletal system.
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OCT 2 2 2003
# 1.3 [510(k) Summary]
K031875 Page 1 of 2
## Inter-Os Technologies, Inc. 7430 E. Park Meadows Drive, Suite 300 Lone Tree, CO 80124
Inter-Os Technologies, Inc. 7430 E. Park Meadows Drive, Suite 300 Lone Tree, CO 80124
Contact: Randolph C. Robinson, MD, DDS 303-708-8390 voice 303-790-7322 fax
Summary Prepared: May 15, 2003
Device Identification:
| Trade Name: | Inter-Os Limb Lengthener |
|----------------------|---------------------------------------------------------------------------------------------|
| Common Name: | Internal Bone Plate Distractor |
| Classification Name: | Single/Multiple component metallic bone fixation appliance and accessories, 21 CFR 888.3030 |
Product Description:
The Inter-Os Limb Lengthener is an implantable device used to treat conditions where bone length is deficient. It is used for distraction osteogenesis techniques in the femur and is intended to be implanted by orthopedic surgeons. The device is removed after distraction is complete. It features two telescoping component bone plates that are distracted apart by a threaded drive shaft. Activation of the drive shaft is by means of a transcutaneous pin, which may be removed once the distraction phase is complete. The Activation Pin and the drive shaft are articulated using an internal gear.
All of the components of the Inter-Os Limb Lengthener are fabricated from stainless steel. The Inter-Os Limb Lengthener is intended to be sold non-sterile. It is a singleuse device. Sterilization instructions are included in the labeling.
#### Indications for Use
The Inter-Os Limb Lengthener is an implantable device for distraction osteogenesis techniques in the femur. The Inter-Os Limb Lengthener is used to treat conditions for limb length deficiencies involving the femur. The types of deformities that fall into this category are:
Traumatic deformities, growth deformities, deformities secondary to tumors and infections, and congenital deformities.
The Inter-Os Limb Lengthener is intended to be used in the upper leg bones of the appendicular skeleton. The Limb Lengthener is not intended to be used for the spine.
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KO31875 Page 2 of 2
The Inter-Os Limb Lengthener is intended for single use and is not meant for repeat sterilization and implantation. The device is to be removed after consolidation of the bone is complete. It is to be used with other commercially-available accessory devices, such as bone screws for fixation to the bone surface. Bone cement is not to be used to fixate the device to the bone; however, commercially-available bone cement may be used on the undersurface of the device to level or stabilize it on a curved surface, or bone cement may also be used to fix the gear in position during the consolidation period.
Predicate Devices
The Inter-Os Limb Lengthener is compared to the Inter-Os Bone Generator (#K993869), Synthes Fixation Plates (#K982222 and K020872), the EBI X-Fix DFS Rail System (#K991941, K000083, K010437, and K021031), the Orthofix/Orthodyne ISKD (#K010322) and others. We believe the Inter-Os device to be substantially equivalent based on the descriptive characteristics, same intended use, and same principle operation of distraction osteogenesis.
Performance has been substantiated by mechanical tests in conformity to standard testing guidelines for equivalent devices and literature review.
### CONCLUSION
Based on the design, materials, function, intended use, the Inter-Os Limb Lengthener is substantially equivalent to the devices currently marketed under the Federal Food. Drug and Cosmetic Act. The Inter-Os Limb Lengthener raises no new safety or effectiveness issues. Therefore, safety and effectiveness are reasonably assured, justifying 510(k) clearance for commercial sale.
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Image /page/2/Picture/1 description: The image is a black and white seal for the Department of Health & Human Services - USA. The seal is circular and contains the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the top half of the circle. The bottom half of the circle contains a stylized image of an eagle.
OCT 2 2 2003
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
Randolph C. Robinson, M.D., D.D.S. President Inter-Os Technologies, Inc. 7430 E. Park Meadows Drive, Suite 300 Lone Tree, CO 80124
Re: K031875
Trade/Device Name: Inter-Os Limb Lengthener Regulation Number: 21 CFR 888.3030 Regulation Name: Single/multiple component metallic bone fixation appliances and accessories Regulatory Class: II Product Code: KTT Dated: September 2, 2003 Received: September 3, 2003
Dear Dr. Robinson:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA). 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 (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA 's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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Page 2 - Randolph C. Robinson, M.D., D.D.S.
This letter will allow you to begin marketing your device as described in your Section 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), please contact the Office of Compliance at (301) 594-4659. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html
Sincerely yours,
Mark A. Melbernan
Celia M. Witten, Ph.D., M.D. Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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### 1.2 Indications Enclosure
Page 1 of 1
Pending K031875 510(k) Number:
Device Name:
#### Intended Uses/Indications
The Inter-Os Limb Lengthener is an implantable device for distraction osteogenesis techniques in the femur. The Inter-Os Limb Lengthener is used to treat conditions for limb length deficiencies involving the femur. The types of deformities that fall into this category are:
Traumatic deformities, growth deformities, deformities secondary to tumors and infections, and congenital deformities.
The Inter-Os Limb Lengthener is intended to be used in the upper leg bones of the appendicular skeleton. The Limb Lengthener is not intended to be used for the spine.
The Inter-Os Limb Lengthener is intended for single use and is not meant for repeat sterilization and implantation. The device is to be removed after consolidation of the bone is complete. It is to be used with other commercially-available accessory devices, such as bone screws for fixation to the bone surface. Bone cement is not to be used to fixate the device to the bone; however, commercially-available bone cement may be used on the undersurface of the device to level or stabilize it on a curved surface, or bone cement may also be used to fix the gear in position during the consolidation period.
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use (Per 21 CFR 801.109) x Over-The-Counter Use
Mark V. Milkerson
ivision Sign-Off) Division of General, Restorative and Neurological Devices
510(k) Number K03875
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.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
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.
