What if the reason your claim keeps getting denied isn't that you aren't "hurt enough," but that you're using an outdated blueprint for a mission that has already changed?

For years, the VA has played gatekeeper with secondary service connection, forcing veterans to prove a "permanent worsening" or a direct, linear cause that often ignored the reality of how service-connected injuries actually break down the body. But as of July 2026, the landscape has shifted. A landmark shift in legal interpretation, centered around the "but-for" standard, has cracked the door open for thousands of veterans who were previously told "no."

At GVC4Vets, we don’t just watch these changes from the sidelines. We analyze them, weaponize them, and put them into the hands of the veterans we serve. If you’re looking for a VA disability increase or trying to connect the dots between your service-connected back pain and your new diagnosis of depression or sleep apnea, this is the "insider" intel you’ve been waiting for.

Table of Contents

1. Key Takeaways
2. The Spicer Shift: Understanding 'But-For' Causation
3. The 2026 M21-1 Update: More Than Just Aggravation
4. Beyond Physical Pain: The Treatment Interference Rule
5. The Blueprint: How to Bridge the Gap for Your Doctor
6. Debunking the '100% Causation' Myth
7. Actionable Checklist for Secondary Claims
8. Frequently Asked Questions

Key Takeaways

• The "But-For" Standard: You no longer need to prove your primary injury is the sole cause of your secondary condition. You only need to show that "but for" the primary injury, the secondary one wouldn't be as severe or wouldn't have occurred.
• No Permanent Worsening Required: Under the latest 38 CFR updates, temporary aggravation is now a valid pathway for secondary service connection.
• Treatment Interference: If your service-connected condition prevents you from treating a non-service-connected issue, you can now claim that issue as secondary.
• Standard of Proof: The burden remains "at least as likely as not" (50% probability), not 100%.

The Spicer Shift: Understanding 'But-For' Causation

For decades, the VA relied on a narrow view of 38 CFR § 3.310. They wanted to see a straight line: A caused B. If B was already there, they wanted to see "permanent worsening" before they’d give you a dime.

That changed with the Federal Circuit’s decision in Spicer v. McDonough. The court effectively told the VA that their "baseline" requirement was a barrier that the law didn't actually support. The new standard is but-for causation.

In tactical terms, this means asking the question: Would this secondary disability be this severe today but for my service-connected condition? If the answer is no, you have a claim. This isn't about subjective "ouch" moments; it's about the objective chain of medical causality.

The 2026 M21-1 Update: More Than Just Aggravation

As of May 1, 2026, the VA updated its internal manual (M21-1) to formally adopt the Spicer ruling. This update is a game-changer for anyone seeking a VA disability increase.

The VA now explicitly recognizes that a service-connected disability can support a secondary claim if it:

1. Caused the secondary condition.
2. Aggravated (worsened) it.
3. Interfered with recovery or treatment for it.

Notice that last point. It’s the one the "experts" don't want you to know about because it requires a higher level of medical evidence to prove.

Beyond Physical Pain: The Treatment Interference Rule

This is where we get into the "language of the rater." Let’s look at 38 CFR § 4.97 or other diagnostic codes. If you have a service-connected knee injury (diagnostic code 5260) that is so painful it prevents you from doing the physical therapy required to treat your non-service-connected plantar fasciitis, that plantar fasciitis is now potentially service-connected under the "interference with treatment" rule.

Confirm your medical records show this interference. Identify the specific ways your service-connected symptoms blocked your recovery. The VA can no longer ignore the "ripple effect" of your primary injuries.

The Blueprint: How to Bridge the Gap for Your Doctor

Your doctor might be a great physician, but they aren't a VA rater. They don't know that a nexus requires specific phrasing to pass through the VA’s administrative gauntlet. You must provide the "data points" they need to write a winning medical opinion.

When you sit down for your evaluation, whether with one of our 800+ independent physicians or your own provider, you must frame the relationship as a partnership. Use this strategy:

• Objective Evidence: Don't just say your back hurts. Tell the doctor how your calcaneal eversion from flat feet is causing a compensatory gait shift that is destroying your lumbar spine.
• The Nexus Language: Ensure the final report uses the magic words: "It is at least as likely as not that the veteran’s secondary condition was caused or aggravated by the service-connected condition. But for the service-connected symptoms, the secondary condition would not have progressed to this level of severity."

Debunking the '100% Causation' Myth

There is a lot of "rater room" chatter suggesting that the VA now requires 100% certainty for secondary claims. This is false.

The legal standard of proof for veterans remains the "benefit of the doubt" doctrine. If the evidence is in "equipoise" (50/50), the veteran wins. The but-for standard doesn't raise the bar to 100%; it simply broadens the types of evidence that can be used to reach that 50% threshold. Don't let a "rushed C&P exam" convince you otherwise. At GVC4Vets, we’ve helped over 100,000 veterans fight back against these administrative delays and incorrect denials.

Actionable Checklist for Secondary Claims

Before you hit "submit" on that VA secondary claim, verify you have checked these boxes:

• Current Diagnosis: You cannot claim a "feeling." You need a diagnosed condition.
• Service-Connected Primary: Confirm the primary condition is already rated (even at 0%).
• The "But-For" Statement: Ensure your medical provider has explicitly addressed how the primary condition interfered with, caused, or worsened the secondary one.
• CFR Reference: Does your evidence align with the criteria in 38 CFR § 3.310?
• Medication Audit: Are any of your secondary issues (like GI distress or weight gain) "but-for" results of medications for your primary condition?

Frequently Asked Questions

Q: Can I file a secondary claim if the condition pre-existed my service?
A: Yes. Under the but-for standard, you aren't proving the service caused the condition from scratch. You are proving that your service-connected disability made it worse than it would have been otherwise.

Q: Does "temporary worsening" count for a rating?
A: Yes. The May 2026 update to the M21-1 manual clarifies that "permanent worsening" is not a requirement for secondary service connection through aggravation.

Q: What if the VA says my secondary condition is just "part of getting older"?
A: This is a classic rater "brush-off." You counter this by having a medical expert provide a nexus that explains why your specific service-connected injury: not age: is the "but-for" cause of the current severity.

Q: How do I handle a denial that says there is no "baseline"?
A: You cite Spicer v. McDonough. The Federal Circuit ruled that a lack of a "baseline" cannot be used as a gatekeeper to deny a claim. If the VA denies you on these grounds, they are violating current legal standards.

The VA disability system is a mission. Like any mission, it requires the right equipment, the right strategy, and the right team. Don't go into the wire without a blueprint. If you're ready to secure the rating you actually deserve, let’s get to work.

Global Vets Consulting (GVC4Vets) – National Veterans Disability Services