510(k) · Cleared
ClearedCastleLoc-S Posterior Cervical Fixation System
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
L&K BIOMED Co., Ltd. · NKG Posterior Cervical Screw System
Cleared on Jul 20, 2023 as substantially equivalent to K143278 (L&K BIOMED Co., Ltd., 2015) and 6 other predicates after a 28-day review. Its family tree reaches back 19 generations to 1985. 1 of the 136 devices in its family, counting itself, has a Class I recall.
- Decided
- Jul 20, 2023
- Review
- 28 days
- Class
- Class II
- Product code
- NKG
- Recalls
- None
- Predicates
- 7
Its longest line of descent runs back 19 generations to K853033 (1985). 135 ancestors in all. No later device cites it as a predicate yet. 1 of the 136 devices in this family, counting this one, has a Class I recall.
- Root · 19 generations backK853033 Hartshill Rect & Wires, Spinal Fixation SystemA.W. Showell (Surgicraft), Ltd. · 1985
- 15 generations between
- 3 generations backK200793 LnK Posterior Cervical Fixation System and CastleLoc-S Posterior…L&K BIOMED Co., Ltd. · 2020
- 2 generations backK210035 ZESPIN SI Joint Fusion System, MegaCerfix Posterior Cervical…Aegis Spine · 2021
- 1 generation backK221050 ZESPIN SI Joint Fusion System, Paeon Posterior Cervical Fixation…Aegis Spine, Inc. · 2022
- This deviceK231840 CastleLoc-S Posterior Cervical Fixation SystemL&K BIOMED Co., Ltd. · 2023
Show all 19 generations
- Root · 19 generations backK853033 Hartshill Rect & Wires, Spinal Fixation SystemA.W. Showell (Surgicraft), Ltd. · 1985
- 18 generations backK965221 Ransford Cervical Fixation SystemSurgicraft, Ltd. · 1997
- 17 generations backK982322 Synthes Spine Occipital-Cervical Plate/Rod and Hook SystemSynthes (Usa) · 1998
- 16 generations backK002733 Summit Occipito-Cervico-Thoracic (Oct) Spinal SystemDepuyacromed · 2000
- 15 generations backK013222 Summit Occipito-Cervico- Thoracic (Oct) Spinal SystemDepuyacromed · 2001
- 14 generations backK022190 Modification to Summit Occipito-Cervico-Thoracic (Oct) Spinal SystemDepuyacromed · 2002
- 13 generations backK030103 Summit Oct Spinal System Minipolyaxial ScrewsDepuyacromed · 2003
- 12 generations backK041203 Summit Oct Spinal SystemDepuy Spine, Inc. · 2004
- 11 generations backK072568 Modification to Oasys SystemStryker Spine · 2007
- 10 generations backK080143 Modification to Stryker Spine Oasys SystemStryker Spine · 2008
- 9 generations backK093670 Modification to: Oasys SystemStryker Spine · 2010 · Recalled (Class I)
- 8 generations backK111719 Oasys Spinal SystemStryker Spine · 2012
- 7 generations backK142741 OASYS SystemStryker Corporation · 2015
- 6 generations backK150753 OASYS SystemStryker Corporation · 2015
- 5 generations backK151755 OASYS (r) SystemStryker Corporation · 2015
- 4 generations backK162136 CastleLoc-S Posterior Cervical Fixation System; LnK Posterior…L&K BIOMED Co., Ltd. · 2016
- 3 generations backK200793 LnK Posterior Cervical Fixation System and CastleLoc-S Posterior…L&K BIOMED Co., Ltd. · 2020
- 2 generations backK210035 ZESPIN SI Joint Fusion System, MegaCerfix Posterior Cervical…Aegis Spine · 2021
- 1 generation backK221050 ZESPIN SI Joint Fusion System, Paeon Posterior Cervical Fixation…Aegis Spine, Inc. · 2022
- This deviceK231840 CastleLoc-S Posterior Cervical Fixation SystemL&K BIOMED Co., Ltd. · 2023
Class I recalls in this family
- K093670 Modification to: Oasys System6 generations back · 2010
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −19 | K853033 | Hartshill Rect & Wires, Spinal Fixation System | A.W. Showell (Surgicraft), Ltd. | 1985 | — |
| −18 | K965221 | Ransford Cervical Fixation System | Surgicraft, Ltd. | 1997 | — |
| −17 | K982322 | Synthes Spine Occipital-Cervical Plate/Rod and Hook System | Synthes (Usa) | 1998 | — |
| −16 | K002733 | Summit Occipito-Cervico-Thoracic (Oct) Spinal System | Depuyacromed | 2000 | — |
| −15 | K013222 | Summit Occipito-Cervico- Thoracic (Oct) Spinal System | Depuyacromed | 2001 | — |
| −14 | K022190 | Modification to Summit Occipito-Cervico-Thoracic (Oct) Spinal System | Depuyacromed | 2002 | — |
| −13 | K030103 | Summit Oct Spinal System Minipolyaxial Screws | Depuyacromed | 2003 | — |
| −12 | K041203 | Summit Oct Spinal System | Depuy Spine, Inc. | 2004 | — |
| −11 | K072568 | Modification to Oasys System | Stryker Spine | 2007 | — |
| −10 | K080143 | Modification to Stryker Spine Oasys System | Stryker Spine | 2008 | — |
| −9 | K093670 | Modification to: Oasys System | Stryker Spine | 2010 | Class I |
| −8 | K111719 | Oasys Spinal System | Stryker Spine | 2012 | — |
| −7 | K142741 | OASYS System | Stryker Corporation | 2015 | — |
| −6 | K150753 | OASYS System | Stryker Corporation | 2015 | — |
| −5 | K151755 | OASYS (r) System | Stryker Corporation | 2015 | — |
| −4 | K162136 | CastleLoc-S Posterior Cervical Fixation System; LnK Posterior Cervical… | L&K BIOMED Co., Ltd. | 2016 | — |
| −3 | K200793 | LnK Posterior Cervical Fixation System and CastleLoc-S Posterior Cervical… | L&K BIOMED Co., Ltd. | 2020 | — |
| −2 | K210035 | ZESPIN SI Joint Fusion System, MegaCerfix Posterior Cervical Fixation System… | Aegis Spine | 2021 | — |
| −1 | K221050 | ZESPIN SI Joint Fusion System, Paeon Posterior Cervical Fixation System, Paeon… | Aegis Spine, Inc. | 2022 | — |
| 0 (this device) | K231840 | CastleLoc-S Posterior Cervical Fixation System | L&K BIOMED Co., Ltd. | 2023 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1990 | 1 | 0 |
| 1992 | 1 | 0 |
| 1993 | 2 | 0 |
| 1995 | 2 | 0 |
| 1996 | 4 | 0 |
| 1997 | 5 | 0 |
| 1998 | 3 | 0 |
| 1999 | 6 | 0 |
| 2000 | 7 | 0 |
| 2001 | 6 | 0 |
| 2002 | 12 | 0 |
| 2003 | 8 | 0 |
| 2004 | 4 | 0 |
| 2005 | 7 | 0 |
| 2006 | 10 | 0 |
| 2007 | 4 | 0 |
| 2008 | 5 | 0 |
| 2009 | 4 | 0 |
| 2010 | 1 | 0 |
| 2011 | 5 | 0 |
| 2012 | 4 | 0 |
| 2013 | 2 | 0 |
| 2014 | 2 | 0 |
| 2015 | 7 | 0 |
| 2016 | 1 | 0 |
| 2018 | 1 | 0 |
| 2019 | 1 | 0 |
| 2020 | 1 | 0 |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
1 device in this family has a Class I recall. A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new NKG device
- #1 K252327 CMORE® CT System; CMORE® CT System Navigated…score 19.6 · 22 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (7)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K143278 | LnK Posterior Cervical Fixation SystemSummary page 4…to the predicate devices in all characteristics. 510k Number Trade or Proprietary or Model Name Predicate Type K 143278 LnK Posterior Cervical Fixation System Primary K 120879 LnK Posterior Cervi… | 2015 |
| * | K120879 | Lexus Cervical Fixation SystemSummary page 4…Proprietary or Model Name Predicate Type K 143278 LnK Posterior Cervical Fixation System Primary K 120879 LnK Posterior Cervical Fixation System K 103414 LnK Posterior Cervical Fixation System… | 2012 |
| * | K103414 | Venus Cervical Spinal Fixation SystemSummary page 4…K 143278 LnK Posterior Cervical Fixation System Primary K 120879 LnK Posterior Cervical Fixation System K 103414 LnK Posterior Cervical Fixation System… | 2011 |
| * | K162136 | CastleLoc-S Posterior Cervical Fixation System; LnK Posterior Cervical Fixation SystemSummary page 4…03414 LnK Posterior Cervical Fixation System Additional K 162136 LnK Posterior Cervical Fixation System and CastleLoc-S K 200793 Posterior Cervical Fixation Syste… | 2016 |
| * | K200793 | LnK Posterior Cervical Fixation System and CastleLoc-S Posterior Cervical Fixation SystemSummary page 4…Additional K 162136 LnK Posterior Cervical Fixation System and CastleLoc-S K 200793 Posterior Cervical Fixation System K 210035 MegaCerfix(Former name) Posterior Cervical Fixation S… | 2020 |
| * | K210035 | ZESPIN SI Joint Fusion System, MegaCerfix Posterior Cervical Fixation System, MegaCerfix…Summary page 4…ional K 162136 LnK Posterior Cervical Fixation System and CastleLoc-S K 200793 Posterior Cervical Fixation System K 210035 MegaCerfix(Former name) Posterior Cervical Fixation System Additional K 221050 Paeon Posterior… | 2021 |
| * | K221050 | ZESPIN SI Joint Fusion System, Paeon Posterior Cervical Fixation System, Paeon Anterior…Summary page 4…K 200793 Posterior Cervical Fixation System K 210035 MegaCerfix(Former name) Posterior Cervical Fixation System Additional K 221050 Paeon Posterior Cervical Fixation System The design feature, indications for use and manufacturing process for the… | 2022 |
What descends from it?
No later submission names this one as a predicate yet.
Has anything in its family been recalled? (1 Class I)
No FDA recall names this device.
Relatives with a Class I recall
Class I is FDA’s most serious recall class. A recall in the family tree is context for this device, not evidence about it.
- K093670Modification to: Oasys SystemStryker Spine · 2010 · 6 generations back · ◆ on the line of descent in FIG. 11 Class I recall
What does this lineage say?
- The line of descent spans 38 years and passes through 10 companies; a new generation was cleared every 1.3 years on median.
- 14 of the 135 ancestors have a recall of any class; 1 has a Class I recall.
- 2 other devices also cite its predicate K143278.
How does its category compare?
All NKG devicesNKG Posterior Cervical Screw System: FDA decisions, review times, recalls and adverse event reports over 20 years. 2023, this device’s year, is highlighted.
FDA decisions per year · NKG
6in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · NKG
58in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · NKG
2in 2020
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · NKG
153in 2025
MAUDE reports naming product code NKG, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 0 | — | 0 | 0 |
| 2008 | 0 | — | 0 | 0 |
| 2009 | 0 | — | 0 | 0 |
| 2010 | 0 | — | 0 | 0 |
| 2011 | 0 | — | 0 | 0 |
| 2012 | 0 | — | 0 | 0 |
| 2013 | 0 | — | 0 | 0 |
| 2014 | 0 | — | 0 | 0 |
| 2015 | 17 | 71 | 0 | 4 |
| 2016 | 16 | 87 | 0 | 73 |
| 2017 | 15 | 108 | 0 | 99 |
| 2018 | 12 | 61 | 1 | 127 |
| 2019 | 8 | 50 | 1 | 214 |
| 2020 | 14 | 59 | 2 | 236 |
| 2021 | 7 | 56 | 0 | 704 |
| 2022 | 7 | 108 | 0 | 175 |
| 2023 | 10 | 58 | 0 | 131 |
| 2024 | 3 | 100 | 0 | 206 |
| 2025 | 6 | 58 | 0 | 153 |
| 2026 | 4 | 169 | 0 | — |
What is it indicated for?
The CastleLoc-S Posterior Cervical Fixation System is intended to provide immobilization and stabilization of spinal segments as an adjunct to fusion for the following acute and chronic instabilities of the cervical spine (C1 to C7) and the thoracic spine (T1-T3): traumatic spinal fractures and/or traumatic dislocations; instability or deformity; failed previous fusions (e.g., pseudoarthrosis); tumors involving the cervical spine; and degenerative…
Read the full statement (170 words)
The CastleLoc-S Posterior Cervical Fixation System is intended to provide immobilization and stabilization of spinal segments as an adjunct to fusion for the following acute and chronic instabilities of the cervical spine (C1 to C7) and the thoracic spine (T1-T3): traumatic spinal fractures and/or traumatic dislocations; instability or deformity; failed previous fusions (e.g., pseudoarthrosis); tumors involving the cervical spine; and degenerative disease, including intractable radiculopathy and/or myelopathy, neck and/or arm pain of discogenic origin as confirmed by radiographic studies, and degenerative disease of the facets with instability. The CastleLoc-S Posterior Cervical Fixation System is also intended to restore the integrity of the spinal column even in the absence of fusion for a limited time period in patients with advanced stage tumors involving the cervical spine in whom life expectancy is of insufficient duration to permit achievement of fusion. The CastleLoc-S Posterior Cervical Fixation System can be linked to the LnK Spinal Fixation System, OpenLoc-L Spinal Fixation System and AccelFix Spinal Fixation System via rod to rod connector and transitional rod.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K231840 · printed Nov 6, 2026
Cite this page
510(k) Report. “K231840: CastleLoc-S Posterior Cervical Fixation System.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K231840
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026