FDA Bone Growth Stimulator Reclassification (2026): From Class III PMA to Class II 510(k) — Regulatory and Reimbursement Impact
On April 16, 2026, the FDA issued a final order reclassifying non-invasive bone growth stimulators (product codes LOF and LPQ) from Class III to Class II. CMS simultaneously updated Medicare billing and fee schedules. This guide covers the reclassification timeline, new special controls, CMS HCPCS changes, and the divergent financial impact on manufacturers Bioventus and Orthofix.
What Happened
On April 16, 2026, the FDA published a final order in the Federal Register (91 FR 20352) reclassifying non-invasive bone growth stimulators — product codes LOF and LPQ — from Class III (premarket approval) to Class II (premarket notification). The devices are now codified under a new classification regulation at 21 CFR 890.5870.
This is not a minor administrative change. It shifts the regulatory pathway for these devices from the most burdensome premarket pathway (PMA) to the significantly less burdensome 510(k) pathway. It also triggers downstream changes in Medicare reimbursement, with CMS updating billing rules and fee schedules effective May 18, 2026.
The global bone growth stimulator market was estimated at over $2 billion in 2025, with Fortune Business Insights projecting growth to $3.5 billion by 2034 at a CAGR of approximately 6.2%. Non-invasive devices represent the majority of this market, making the reclassification financially consequential for every participant.
The financial consequences for the two dominant US manufacturers — Bioventus (Exogen ultrasound system) and Orthofix (SpinalStim and PhysioStim PEMF devices) — diverge sharply.
Background: A Six-Year Reclassification Journey
Original Classification
Non-invasive bone growth stimulators were classified as postamendments Class III devices, meaning they automatically required PMA approval. These devices promote osteogenesis as an adjunct to fracture healing or spinal fusion using three technology platforms:
- Capacitive coupling (CC) — applies electric field through external electrodes
- Pulsed electromagnetic field (PEMF) — generates electromagnetic field via external coils
- Combined magnetic field (CMF) — combines static and time-varying magnetic fields
- Ultrasound — delivers low-intensity pulsed ultrasound (LIPUS)
The dominant products on the US market include Bioventus's Exogen (ultrasound), Orthofix's SpinalStim and PhysioStim (PEMF), and Zimmer Biomet's SpinalPak (PEMF).
The Path to Reclassification
| Date | Event |
|---|---|
| August 17, 2020 | FDA published proposed order to reclassify from Class III to Class II (85 FR 49986) |
| September 8–9, 2020 | FDA Orthopaedic and Rehabilitation Devices Panel met to discuss reclassification |
| 2020–2025 | Public comment period and FDA review of panel recommendations and stakeholder input |
| April 16, 2026 | FDA issued final order reclassifying to Class II with special controls |
Orthofix notably opposed reclassification during the advisory panel meeting, arguing that Class III designation was necessary to ensure patient safety and therapy efficacy. Bioventus did not publicly oppose the change. The panel ultimately recommended reclassification to Class II with appropriate special controls.
Why the FDA Reclassified
The FDA's rationale for reclassification rests on three findings:
Sufficient information exists to establish special controls. Decades of PMA data, clinical studies, and post-market surveillance have characterized the risks and established effective mitigation strategies.
Special controls, combined with general controls, provide reasonable assurance of safety and effectiveness. The FDA identified five primary risks and corresponding mitigation measures.
Reduced regulatory burden will improve patient access. The 510(k) pathway is faster and less costly than PMA, enabling more manufacturers to develop competing devices.
Risks Identified and Special Controls
The FDA identified five primary risks associated with non-invasive bone growth stimulators and established corresponding special controls:
| Risk to Health | Mitigation Measure |
|---|---|
| Failure or delay of osteogenesis | Clinical performance data including imaging evidence of fusion |
| Adverse tissue reaction | Biocompatibility evaluation per ISO 10993 |
| Electrical or ultrasound energy causing harm | Performance testing demonstrating energy output safety |
| Device malfunction or failure | Reliability testing and electromagnetic compatibility (EMC) data |
| Inadequate labeling leading to misuse | Comprehensive labeling including contraindications, warnings, and instructions for use |
Manufacturers submitting a 510(k) for a non-invasive bone growth stimulator must demonstrate compliance with all special controls.
What Changes for Manufacturers
From PMA to 510(k)
| Element | Class III (PMA) | Class II (510(k)) |
|---|---|---|
| Submission type | PMA application | 510(k) premarket notification |
| Typical review timeline | 180–360 days (often longer) | 90 days (FDA target) |
| Clinical data requirement | Full clinical investigation typically required | Substantial equivalence to predicate; clinical data may not always be required |
| Annual report | Required (PMA annual report) | Not required in the same form |
| Cost to manufacturer | $100K–$1M+ (PMA preparation) | $25K–$150K (510(k) preparation) |
| Post-approval requirements | PMA supplements for most changes | New 510(k) only for significant changes |
This shift dramatically lowers the barrier to entry for new manufacturers and reduces the ongoing compliance burden for existing ones.
For Currently Marketed Devices
Manufacturers with existing PMA-approved non-invasive bone growth stimulators do not need to immediately submit a 510(k). The FDA's final order allows currently marketed devices to continue being sold. However:
- PMA supplements are no longer required for modifications. Instead, manufacturers must determine whether changes require a new 510(k) under 21 CFR 807.81.
- PMA annual reports will transition to the 510(k) post-market framework.
- New manufacturers entering the market will use the 510(k) pathway rather than PMA.
The CMS Reimbursement Fallout
The reclassification triggered immediate action from CMS. On May 18, 2026, new billing requirements and fee schedule amounts took effect for three HCPCS codes:
| HCPCS Code | Description | Change |
|---|---|---|
| E0747 | Osteogenesis stimulator, electrical, non-invasive, other than spinal | Reclassified to Class II; KF modifier no longer required |
| E0748 | Osteogenesis stimulator, electrical, non-invasive, spinal | Reclassified to Class II; KF modifier no longer required |
| E0760 | Osteogenesis stimulator, non-invasive, ultrasound | Reclassified to Class II; KF modifier no longer required |
CMS updated the DMEPOS fee schedule amounts for these codes to reflect the change from Class III to Class II. The July 2026 DMEPOS fee schedule update will include the fully recalculated fees.
For claims with dates of service on or after May 18, 2026, these HCPCS codes must be billed without the KF modifier.
Orthofix: Negative Impact
Orthofix disclosed in an 8-K filing that it expects average Medicare reimbursement for the affected HCPCS codes to decline by approximately 10%. The company revised its 2026 financial guidance:
| Metric | Updated 2026 Guidance |
|---|---|
| Net sales | $838–$848 million |
| Non-GAAP adjusted EBITDA | $90–$93 million |
| Free cash flow | Not expected to be positive |
| Three-year financial targets | Withdrawn |
Orthofix cited the combined effect of FDA reclassification and CMS billing and fee schedule changes as the driver. The company withdrew its three-year financial targets pending further assessment of long-term CMS actions.
Bioventus: Minimal Near-Term Impact
Bioventus, which markets the Exogen ultrasound bone healing system, struck a more measured tone. In its 8-K filing, the company stated that it does not expect the reimbursement changes to materially affect fiscal year 2026 results and is reiterating its previously issued financial guidance.
Bioventus reported Q1 2026 adjusted diluted EPS of $0.15 (beating the $0.09 consensus estimate by 67%) and revenue of $132.1 million, up 7% year-over-year. The company attributed the limited near-term impact to its payer mix and the timing of CMS fee schedule recalculations.
However, Bioventus cautioned that it will continue monitoring potential long-term effects of current and future CMS actions, and that further changes to Medicare reimbursement rates could require a revision of its financial outlook.
Strategic Implications
For Incumbent Manufacturers
The reclassification creates a tension: lower regulatory burden makes it easier to introduce product improvements (positive), but the CMS fee schedule revision reduces Medicare reimbursement (negative). Incumbents must balance faster innovation cycles against tighter reimbursement economics.
The key strategic consideration is payer mix. Manufacturers with greater exposure to Medicare — versus commercial insurance or cash-pay — will feel the reimbursement reduction more acutely. Orthofix's 10% average reimbursement decline and withdrawn financial targets suggest higher Medicare exposure.
For New Entrants
The 510(k) pathway dramatically lowers the barrier to market entry. Where previously a new bone growth stimulator manufacturer needed to invest in a full PMA clinical program (often $5M–$20M+), they can now pursue 510(k) clearance by demonstrating substantial equivalence to an existing predicate device.
This will likely attract new competitors — including both domestic startups and international manufacturers — to the US non-invasive bone growth stimulator market. Increased competition could further pressure pricing, particularly in the Medicare segment.
For Hospitals and Physicians
The reclassification has mixed implications for the clinical side:
- Lower device costs may eventually result from increased competition
- More product options as new manufacturers enter the market
- Billing changes require immediate attention — claims must drop the KF modifier for dates of service on or after May 18, 2026
- Prior authorization criteria may evolve as payers adjust policies to reflect Class II status
What to Watch Next
July 2026 DMEPOS fee schedule update — CMS will publish fully recalculated fee schedule amounts reflecting the Class II designation. Watch for whether the fee reduction is larger or smaller than the initial 10% that Orthofix reported.
New 510(k) submissions — Monitor the FDA 510(k) database for new submissions under product codes LOF and LPQ. The number and pace of new entries will indicate how quickly competition is intensifying.
Commercial payer responses — Private insurers typically follow CMS lead on fee schedule adjustments, but with a lag. Watch for updated coverage policies from major payers.
State Medicaid updates — Some state Medicaid programs (e.g., Wisconsin's ForwardHealth) were still referencing Class III status as of late May 2026. These programs will need to update their prior authorization criteria.
Potential for further FDA classification actions — The bone growth stimulator reclassification is part of a broader trend. The FDA's 2026 guidance agenda and recent Federal Register activity suggest more reclassifications and 510(k) exemption proposals are coming.