← Product Code [NKB](/submissions/OR/subpart-d%E2%80%94prosthetic-devices/NKB) · K253940 # M.U.S.T. Pedicle Screw System - Extension (K253940) _Medacta International S.A. · NKB · Apr 28, 2026 · Orthopedic · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/OR/subpart-d%E2%80%94prosthetic-devices/NKB/K253940 ## Device Facts - **Applicant:** Medacta International S.A. - **Product Code:** [NKB](/submissions/OR/subpart-d%E2%80%94prosthetic-devices/NKB.md) - **Decision Date:** Apr 28, 2026 - **Decision:** SESE - **Submission Type:** Traditional - **Regulation:** 21 CFR 888.3070 - **Device Class:** Class 2 - **Review Panel:** Orthopedic - **Attributes:** Therapeutic ## Indications for Use The M.U.S.T. Pedicle screw system is intended for posterior non-cervical pedicle fixation (T1-S2/ilium) and non-pedicle fixation, or anterolateral fixation (T8-L5). These devices are indicated as an adjunct to fusion for all of the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma (i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis, and/or lordosis); tumor; pseudoarthrosis; and failed previous fusion in skeletally mature patients. ## Device Story M.U.S.T. Pedicle Screw System - Extension is a spinal fixation system comprising various implants: lateral/coaxial lateral/rod-to-rod connectors, hooks, cross-connectors, S2AI screws (with/without HA coating), and pre-contoured rods. Used in surgical settings by physicians for spinal stabilization. Implants are provided sterile, single-use. System provides mechanical support to the spine as an adjunct to fusion. Clinical decision-making is supported by radiographic confirmation of spinal pathology. Benefits include stabilization of spinal segments to facilitate fusion in patients with degenerative, traumatic, or structural spinal conditions. ## Clinical Evidence No clinical studies were conducted. Substantial equivalence is supported by non-clinical bench testing, including design validation, static/dynamic compression and torsion testing (ASTM F1717), axial gripping tests (ASTM F1798), and dynamic four-point bending (ASTM F2193). ## Technological Characteristics Implants made of Ti6Al4V or CoCrMo. S2AI screws available with/without HA coating. System includes connectors, hooks, and pre-contoured rods for Ø5.5 or Ø6.0 mm rods. Mechanical testing performed per ASTM F1717, F1798, and F2193. Sterilized, single-use, sterile-packed. No software or electronic components. ## Regulatory 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 - M.U.S.T. Pedicle Screw System – Extension ([K234048](/device/K234048.md)) - M.U.S.T. Extension ([K141044](/device/K141044.md)) - M.U.S.T. Pedicle Screw System ([K162061](/device/K162061.md)) - M.U.S.T. Pedicle Screw System ([K193365](/device/K193365.md)) ## Submission Summary (Full Text) > This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com. > > Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/). {0} FDA U.S. FOOD & DRUG ADMINISTRATION April 28, 2026 Medacta International S.A. % Christopher Lussier Senior Director, Quality and Regulatory Medacta USA 6386 Global Dr., Suite 101 Memphis, Tennessee 38141 Re: K253940 Trade/Device Name: M.U.S.T. Pedicle Screw System - Extension Regulation Number: 21 CFR 888.3070 Regulation Name: Thoracolumbosacral Pedicle Screw System Regulatory Class: Class II Product Code: NKB, KWP, KWQ Dated: December 9, 2025 Received: December 9, 2025 Dear Christopher Lussier: 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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading. If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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. Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" U.S. Food & Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 www.fda.gov {1} K253940 - Christopher Lussier Page 2 (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download). Your device is also subject to, among other requirements, the Quality Management System Regulation (QMSR) (21 CFR Part 820), which includes, but is not limited to, ISO 13485 clause 7.3 (Design controls), ISO 13485 clause 8.3 (Nonconforming product), ISO 13485 clause 8.5.2 (Corrective action), and ISO 13485 clause 8.5.3 (Preventative action). Please note that regardless of whether a change requires premarket review, the QMSR requires device manufacturers to review and approve changes to device design and production (ISO 13485 clause 7.3 and ISO 13485 clause 7.5) and document changes and approvals in the Medical Device File (ISO 13485 clause 4.2.3). 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); medical device reporting (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the Quality Management System Regulation (QMSR) (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050. All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems. For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100). {2} K253940 - Christopher Lussier Page 3 Sincerely, COLIN O'NEILL -S Colin O'Neill, M.B.E. Acting Assistant Director DHT6B: Division of Spinal Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health Enclosure {3} K253940 - Page 1 of 1 | Indications for Use | | | | --- | --- | --- | | Please type in the marketing application/submission number, if it is known. This textbox will be left blank for original applications/submissions. | K253940 | ? | | Please provide the device trade name(s). | | ? | | M.U.S.T. Pedicle Screw System - Extension | | | | Please provide your Indications for Use below. | | ? | | The M.U.S.T. Pedicle screw system is intended for posterior non-cervical pedicle fixation (T1-S2/ilium) and non-pedicle fixation, or anterolateral fixation (T8-L5). These devices are indicated as an adjunct to fusion for all of the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma (i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis, and/or lordosis); tumor; pseudoarthrosis; and failed previous fusion in skeletally mature patients. | | | | Please select the types of uses (select one or both, as applicable). | ☑ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C) | ? | {4} M.U.S.T. Pedicle Screw System - Extension Traditional 510(k) K253940 - Page 1 of 4 Medacta International SA # 510(k) Summary ## I. Submitter Medacta International SA Strada Regina 6874 Castel San Pietro (CH) Switzerland Phone (+41) 91 696 60 60 Fax (+41) 91 696 60 66 Contact Person: Stefano Baj, Group VP Regulatory, Legal, and Compliance, Medacta International SA Applicant Correspondent: Chris Lussier, Senior Director, Quality and Regulatory, Medacta USA Date Prepared: December 09, 2025 Date Revised: April 28, 2026 ## II. Device | Device Proprietary Name: | M.U.S.T. Pedicle Screw System - Extension | | --- | --- | | Common or Usual Name: | Thoracolumbosacral pedicle screw system | | Classification Name: | Thoracolumbosacral pedicle screw system | | Primary Product Code | NKB | | Secondary Product Code | KWP, KWQ | | Regulation Number: | 21 CFR 888.3070, 21 CFR 888.3050, 21 CFR 888.3060 | | Device Classification | II | ## III. Predicate Devices Primary Predicate: - M.U.S.T. Pedicle Screw System – Extension, K234048 Additional Predicates: - M.U.S.T. Extension, K141044 - M.U.S.T. Pedicle Screw System, K162061 - M.U.S.T. Pedicle Screw System, K193365 ## IV. Device Description The M.U.S.T. Pedicle Screw System - Extension includes the following implants: - M.U.S.T. Lateral, Coaxial Lateral and Rod to Rod Connectors for Ø5.5 or Ø6.0 mm rods; - M.U.S.T. Connector Ti Setscrew; - M.U.S.T. Hooks for Ø5.5 or Ø6.0 mm rods; - M.U.S.T. MC – Cross-Connectors intermediate size for both “straight” and “adjustable” configurations; {5} M.U.S.T. Pedicle Screw System - Extension Traditional 510(k) K253940 - Page 2 of 4 Medacta International SA - M.U.S.T. S2AI Ø7 screws with length from 20mm to 60mm and with length 120mm, for both HA and non-HA coating variants; - M.U.S.T. S2AI Ø8, 9, 10 HA coated screws available for all the screws lengths of the non-HA range (addition of Ø8 screws lengths from 20 to 60 mm, Ø9 screws lengths from 30 to 60 mm, Ø10 screws lengths from 30 to 65 mm); - M.U.S.T. Pre-Contoured rods of different lengths, curvature and diameters (Ø5.5 or Ø6.0 mm) made of Ti6Al4V or CoCrMo. The M.U.S.T. Pedicle Screw System - Extension implants are provided individually packed, sterile and single-use. ## V. Indications for Use The M.U.S.T. Pedicle screw system is intended for posterior non-cervical pedicle fixation (T1-S2/ilium) and non-pedicle fixation, or anterolateral fixation (T8-L5). These devices are indicated as an adjunct to fusion for all of the following indications: degenerative disc disease (defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies); spondylolisthesis; trauma (i.e., fracture or dislocation); spinal stenosis; curvatures (i.e., scoliosis, kyphosis, and/or lordosis); tumor; pseudoarthrosis; and failed previous fusion in skeletally mature patients. ## VI. Comparison of Technological Characteristics The subject M.U.S.T. Pedicle Screw System - Extension and the predicate devices (K141044, K162061, K193365, K234048) are substantially equivalent with respect to the following characteristics: - Indications for use; - Design of MC Cross-connectors, S2AI Pedicle Screws and Pre-contoured rods; - Materials, except for the addition of compatibility with titanium setscrews for connectors and hooks; - Coating, if available; - Biocompatibility; - Device usage; - Packaging; - Shelf-life; and - Sterilization. The subject M.U.S.T. Pedicle Screw System - Extension differ from the predicate devices with respect to: - Range of products; - Design of Rod-to-rod connectors, Lateral connectors and Hooks; - Rod compatibility for rod-to-rod connectors, lateral connectors and hooks; ## Discussion The comparison of technological characteristics and performance data provided within the submission supports the substantial equivalence of the subject devices with respect to the predicate devices. {6} M.U.S.T. Pedicle Screw System - Extension Traditional 510(k) K253940 - Page 3 of 4 Medacta International SA ## VII. Performance Data Based on the risk analysis, testing activities were conducted to written protocols. The following validations and tests are provided in support of the substantial equivalence determination: ## Non-Clinical Studies - DESIGN VALIDATION - Design Validation for Rod-to-Rod Connectors; - Design Validation for Hooks and Lateral connectors; - Design Comparison Analysis for Lateral connector (Ø5.5-6), Coaxial Lateral connectors (Ø5.5-6), Hooks (Ø5.5-6); - Design Comparison Analysis for MUST MC Cross Connectors 23-35mm; - Design Comparison Analysis for MUST S2AI screws and Pre-Contoured Rods. - PERFORMANCE TESTING - Static compression strength test of the M.U.S.T. construct with Rod-to-Rod Connectors in accordance with ASTM F1717; - Static torsion strength test of the M.U.S.T. construct with Rod-to-Rod Connectors in accordance with ASTM F1717; - Dynamic compression strength test of the M.U.S.T. construct with Rod-to-Rod Connectors in accordance with ASTM F1717; - Axial Gripping test for M.U.S.T. Hooks and M.U.S.T. Uniplanar Screws both for Ø5.5 and Ø6 Rods in accordance with ASTM F1798; - Dynamic four-point bending test for spinal rods in accordance with ASTM F2193; - Justification to use M.U.S.T. SI Screw validation activity to characterize M.U.S.T. S2AI screw. - PYROGENICITY - Bacterial endotoxin test (LAL test) according to European Pharmacopoeia §2.6.14 (which is equivalent to USP chapter <85> and USP <161>) - Pyrogen test according to USP chapter <151> for pyrogenicity determination - The subject devices are not labeled as non-pyrogenic or pyrogen free. - BIOCOMPATIBILITY assessment - SHELF-LIFE evaluation ## Clinical Studies: - No clinical studies were conducted. {7} M.U.S.T. Pedicle Screw System - Extension Traditional 510(k) K253940 - Page 4 of 4 Medacta International SA ## VIII. Conclusion The information provided above supports that the subject devices are substantially equivalent to the predicate devices. --- **Source:** [https://fda.innolitics.com/submissions/OR/subpart-d%E2%80%94prosthetic-devices/NKB/K253940](https://fda.innolitics.com/submissions/OR/subpart-d%E2%80%94prosthetic-devices/NKB/K253940) **Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact). **Cite:** Innolitics at https://innolitics.com