Serving Marin County, the greater San Francisco Bay Area, and California from our San Rafael office — and representing Mobi-C clients nationally where appropriate. Synergist Law, P.C. is a boutique personal injury firm led by Sami Sedghani, Pharm.D., J.D., an accomplished trial attorney with clinical pharmacy training. We actively handle Mobi-C cervical artificial disc cases involving device fracture, subsidence, migration, heterotopic ossification, adjacent-segment disease, and revision surgery.
What is the Mobi-C cervical disc?
The Mobi-C Cervical Disc Prosthesis is an artificial intervertebral disc designed to replace a diseased or damaged cervical disc in the neck. It was originally developed by LDR Spine, which was acquired by Zimmer Biomet in 2016; the spine business is now operated as Highridge Medical. The device received U.S. Food and Drug Administration Premarket Approval (PMA) in August 2013 for single-level cervical disc replacement and in 2015 for two-level replacement — making it the first FDA-approved cervical artificial disc for two contiguous levels.
The Mobi-C has three components: two cobalt-chromium-molybdenum metal endplates with titanium plasma-sprayed hydroxyapatite coating (for bone ongrowth), and a mobile ultra-high-molecular-weight polyethylene (UHMWPE) core designed to permit controlled motion between the plates. It is implanted during an anterior cervical procedure, using instruments supplied by the manufacturer that include a specialized “depth-stop” inserter.
Who gets a Mobi-C and why
Mobi-C is implanted during cervical disc replacement (CDR) surgery, generally offered as a motion-preserving alternative to anterior cervical discectomy and fusion (ACDF). Typical candidates are adult patients with symptomatic cervical degenerative disc disease at one or two contiguous levels from C3–C7, with radiculopathy or myelopathy that has not resolved with at least six weeks of conservative management.
The marketing proposition compared to fusion was straightforward: preserve segmental motion at the operative level, reduce load transfer to adjacent levels, and lower the long-term risk of adjacent-segment disease (ASD) — the accelerated degeneration of the disc above or below a fused segment. For many patients, those represent real tradeoffs worth considering. For some, the device has not delivered what the IDE trial data and physician-facing labeling suggested.
What has gone wrong with the Mobi-C
Publicly reported Mobi-C failures and litigation have focused on several recurring patterns:
- Device fracture. The UHMWPE core cracking or breaking apart, with fragments potentially migrating into the spinal canal. Allegations in publicly filed cases have included that sterilization and manufacturing processes contributed to polyethylene brittleness.
- Subsidence. The implant settling into the adjacent vertebral endplate, collapsing disc height and loading the levels above and below.
- Migration or extrusion. The device shifting from its implanted position, in some cases requiring urgent revision surgery.
- Heterotopic ossification (HO). Abnormal bone formation around the implant, eliminating the intended motion-preserving function and effectively converting the segment to a fusion — the opposite of what the device was selected to accomplish.
- Adjacent-segment disease presenting earlier or more severely than disclosed in the IDE trial data or in physician-facing labeling.
- Spinal cord injury from fractured components or from over-depth placement, in extreme cases resulting in permanent neurological deficits up to tetraplegia.
- Surgical-instrument failures, including allegations that the manufacturer-supplied depth-stop mechanism on the inserter failed, allowing surgeons to inadvertently seat the device too deep.
- Revision surgery complications. Explantation of a cervical disc replacement is technically more difficult than disclosed in the original labeling, with higher reported complication rates — often requiring conversion to multi-level fusion.
MAUDE, MDRs, and the publicly reported litigation
The FDA’s MAUDE database (Manufacturer and User Facility Device Experience) collects Medical Device Reports (MDRs) filed by manufacturers, hospitals, and physicians when a device may have contributed to a death or serious injury. For Mobi-C specifically, MAUDE contains reports describing device fracture, migration, heterotopic ossification, revision surgery, and neurological injury.
Publicly reported Mobi-C litigation has included claims alleging:
- Device fracture and migration into the spinal canal causing cervical cord injury, including a widely reported case alleging C6 spinal cord injury and resulting quadriplegia.
- Defective manufacturing or sterilization processes that allegedly rendered the polyethylene core brittle (oxidation and oxygen-exposure issues).
- Failure to timely report Medical Device Reports to the FDA.
- Surgical-instrument defects causing over-depth placement and spinal cord contusion.
- Failure-rate statistics in post-market real-world use that reportedly diverge from the IDE trial data.
A proper Mobi-C case workup includes pulling the device’s MAUDE record, tracing FDA warning-letter history for the manufacturer and any contract sterilizers, and comparing the specific patient’s clinical experience against the pre-market IDE trial representations in the labeling and the published medical literature. That technical workup is where cases that could survive a preemption motion get distinguished from cases that will not.
Why Mobi-C cases are legally complex — the preemption problem
Because the Mobi-C is a Class III device approved through the Premarket Approval (PMA) pathway, defense counsel in nearly every Mobi-C case will move to dismiss on federal preemption grounds under the Medical Device Amendments of 1976 (21 U.S.C. § 360k) and the Supreme Court’s decision in Riegel v. Medtronic, Inc., 552 U.S. 312 (2008).
Under Riegel, state-law tort claims that would impose requirements “different from, or in addition to” the specific FDA requirements imposed through the PMA process are preempted. For a PMA Class III device like the Mobi-C, that broadly covers claims alleging the device’s design, manufacture, or labeling was inadequate — because the FDA has approved all three.
Parallel claims survive. The Supreme Court in Medtronic, Inc. v. Lohr, 518 U.S. 470 (1996), and the Riegel Court itself preserved state-law claims that are “parallel” to federal requirements — that is, claims alleging the manufacturer violated a specific FDA requirement, with the state-law claim seeking to enforce that same requirement rather than add a new one. Mobi-C parallel claims we evaluate include:
- Current Good Manufacturing Practice (CGMP) violations — where the manufacturer or a contract sterilizer failed to follow its FDA-approved manufacturing or sterilization specifications, and that violation caused the specific device’s failure.
- Mislabeling against the FDA-approved labeling — promoting the device for uses not authorized by the PMA, or omitting warnings the FDA required.
- Failure to submit required Medical Device Reports under 21 C.F.R. Part 803 — failing to timely report deaths, serious injuries, or malfunctions that could cause them.
- Off-label marketing that violates FDA requirements, where state consumer-protection or product-liability law prohibits the same conduct.
The preemption analysis in a Mobi-C case is case-dispositive and should be worked up before filing, not after a motion to dismiss. We evaluate the specific device, specific lot and batch, specific failure mode, and specific FDA record before committing to a case theory.
What to document if you have symptoms after a Mobi-C
If you were implanted with a Mobi-C and are experiencing worsening neck pain, radiating arm pain, weakness, numbness, loss of mobility, or your surgeon has recommended revision surgery — preservation of specific records matters more than most patients realize. Save or request:
- Operative report from the original implantation surgery, including the surgeon’s description of the device size and level(s) implanted.
- Device identifier information — the lot number, serial number, and part number of the specific implanted device (usually found on peel-off labels that go into the operative record and into the patient’s implant card).
- Post-operative imaging — especially flexion/extension x-rays and CT or MRI studies ordered because of symptoms.
- All treatment records from the implanting surgeon, any pain management physician, physical therapist, or neurologist.
- Revision surgery records, including the explant pathology/imaging if the device has been removed.
- Any correspondence you have received from the manufacturer, the hospital, or an attorney referencing a product recall or product safety notice.
Equally important: do not undergo revision surgery without consulting a lawyer first unless it is medically urgent. The explanted device itself is critical evidence; it should be preserved, photographed, and retained for product analysis rather than discarded by the hospital after pathology.
California law that potentially impacts your Mobi-C case
- Statute of limitations. California personal-injury claims generally run on a two-year clock under CCP § 335.1. The discovery rule often applies in device cases, delaying accrual until the patient knew or reasonably should have known that the device caused the injury — which may not be the day of surgery.
- Medical-negligence overlay. Where an implanting surgeon’s performance is also at issue, MICRA applies under CCP § 340.5 — one year from discovery with a three-year outer limit, and California’s non-economic damages caps apply.
- Products liability. California applies strict products liability under Greenman v. Yuba Power Products (1963) 59 Cal.2d 57, with design-defect tested under the risk-benefit test of Barker v. Lull Engineering (1978) 20 Cal.3d 413. For PMA devices, the preemption analysis above controls which theories remain viable.
- Comparative fault. California applies pure comparative negligence under Li v. Yellow Cab Co. (1975) 13 Cal.3d 804.
- Prop 51 apportionment of non-economic damages (Civ. Code § 1431.2).
- MDL and JCCP coordination. If a federal multidistrict litigation (MDL) or a California Judicial Council Coordinated Proceeding (JCCP) is formed for Mobi-C cases, the decision whether to join or pursue a standalone California matter is strategic and consequential.
- Medi-Cal, Medicare, and ERISA liens are near-universal in device cases and are often negotiable. Lien planning starts at the beginning of the case, not at settlement.
How Synergist Law prepares a Mobi-C case
- Clinical fluency as first-chair work. Reading the operative report, the device labeling, the implant card, the FDA approval order, and the post-market MDRs is work we do ourselves rather than outsourcing to a “medical consultant.” Sami’s Pharm.D. training (UCSF) and prior work on the defense side at national firms for pharmaceutical and device clients means the vocabulary and the mechanics are already in-house.
- Preemption workup before filing. We analyze which parallel claim theories a specific device/lot/failure pattern will support, rather than filing a boilerplate complaint and hoping to survive a 12(b)(6) motion.
- Explant preservation. We coordinate with the revision surgeon and the hospital to preserve the explanted device for metallurgic, polymer, and failure-mode analysis.
- MAUDE and warning-letter pulls at intake, so we know the public FDA record before we evaluate the client’s specific device.
- Boutique attention. You will not be handed off to a case manager or junior associate. Sami personally works your file from intake through resolution.
- Trial-ready preparation. We work every case as if it will try, which is why most do not.
- No attorney’s fee unless we recover. You may be responsible for advanced costs depending on your written fee agreement. Standard contingency representation, with case costs advanced by the firm.
Mobi-C cervical disc lawsuit FAQ
What is the Mobi-C cervical disc?
The Mobi-C is a cervical artificial disc prosthesis, originally made by LDR Spine (now Zimmer Biomet / Highridge Medical), approved by the FDA via the Premarket Approval (PMA) pathway in 2013 for single-level cervical disc replacement and in 2015 for two-level. It is marketed as a motion-preserving alternative to anterior cervical discectomy and fusion (ACDF).
What are the known Mobi-C problems?
Publicly reported Mobi-C failure modes include device fracture (including the UHMWPE core), subsidence, migration or extrusion, heterotopic ossification that converts the segment to a de-facto fusion, adjacent-segment disease, spinal cord injury from fractured components or over-depth placement, and complications from revision surgery to explant the device.
Can I sue the manufacturer if my Mobi-C failed?
Possibly, but federal preemption makes Mobi-C cases legally complex. Because the Mobi-C is a Class III PMA device, state-law claims face preemption under Riegel v. Medtronic (2008) 552 U.S. 312. Parallel claims alleging a specific FDA violation (CGMP violations, mislabeling against approved labeling, failure to file MDRs, off-label marketing) survive and are the typical path forward. Early preemption analysis of your specific device, lot, and failure mode is essential.
Is there a Mobi-C MDL or class action?
As of this writing there is active publicly reported Mobi-C litigation in state and federal courts, and the manufacturer landscape has evolved (LDR Spine → Zimmer Biomet → Highridge Medical). Whether a federal MDL or California JCCP has been established, or will be, affects the strategy for an individual case. We check the current MDL/JCCP status at intake and discuss with every client whether coordination is in their interest or whether a standalone case is stronger.
How long do I have to file a Mobi-C case in California?
Generally two years from the date you knew or reasonably should have known the device caused your injury, under CCP § 335.1 with the discovery rule. Where the implanting surgeon’s negligence is also at issue, MICRA deadlines apply under CCP § 340.5 (one year from discovery, three-year outer limit). Minors and certain other situations have different clocks. Because the deadline depends on the facts, it is better to have a licensed California attorney determine the deadline that applies than to calculate it yourself.
Will my revision surgery destroy the evidence?
If the revision is not medically urgent, consult a lawyer before scheduling. The explanted device is critical physical evidence and should be preserved, photographed, and chain-of-custody-retained for metallurgic, polymer, and failure-mode analysis rather than discarded by hospital pathology. If the revision is urgent, call us before surgery if possible so we can coordinate with the surgeon and the hospital on preservation.
How much does a Mobi-C lawyer cost?
Contingency fee: no attorney’s fee unless we obtain a recovery for you. Depending on the terms of your written fee agreement, you may be responsible for case costs we advance even if there is no recovery. Your fee agreement explains this before representation begins. Case costs include MAUDE pulls, FDA records, metallurgic and polymer experts, treating-physician depositions, biomechanical analysis, and life-care planner fees. Initial case evaluations are free and confidential.
What is a Mobi-C case worth?
There is no reliable bracket. Value depends on severity of injury (chronic pain only vs. revision surgery vs. permanent neurological deficit), causation strength, the specific FDA record for your lot/batch, applicable preemption defenses, available defendants, venue, and the quality of the life-care plan and economic analysis. We do not quote numbers before reviewing the file.
Do you handle Mobi-C cases outside California?
Yes. The firm is based in California and most of our matters are California-venued, but Mobi-C and other cervical disc replacement cases often involve federal court, MDL coordination, and multi-state fact patterns. Where appropriate, we handle Mobi-C cases nationally.
How does Sami’s Pharm.D. background help a Mobi-C case?
Mobi-C cases turn on reading the device, the FDA record, and the medicine — the PMA approval order, the labeling, the IFU (instructions for use), the physician training materials, the MAUDE reports, the real-world evidence studies, and the clinical course of the specific patient. A lawyer with clinical training reads those documents natively, and prepares treating surgeons and retained engineering and medical experts to meet defense cross-examination head-on.
Talk to a California Mobi-C cervical disc lawyer today
If you or a loved one was implanted with a Mobi-C and has experienced device fracture, subsidence, migration, heterotopic ossification, adjacent-segment disease, revision surgery, or spinal cord injury — Synergist Law, P.C. offers a free, confidential case evaluation. Call (415) 835-4448 or contact us online. Serving Marin County, the Bay Area, all of California, and Mobi-C clients nationally where appropriate.
Attorney Advertising. The information on this page is for general informational purposes only and does not constitute legal or medical advice. Reading this page, contacting the firm, or submitting a case inquiry does not create an attorney–client relationship. Past results do not guarantee a similar outcome. Statements regarding publicly reported litigation reflect public filings and reporting; they are not representations about any specific client’s case or likelihood of recovery. For advice about your specific situation, consult a licensed California attorney.