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There are two routes, not one
Most people only ever hear about the first one. The second one is real money.
- Route one — causation. 38 CFR 3.310(a). A condition that is "proximately due to or the result
of" a service-connected disability. Your rated knee changes how you walk; the changed walk wears out your
hip; you claim the hip.
- Route two — aggravation. 38 CFR 3.310(b). You had a condition that is not service
connected, and your service-connected disability made it worse. VA pays for the increase — the amount it
got worse — as long as the worsening is not just the natural progress of that disease.
On route two, do not let anybody tell you that you need records from before it got worse. The
regulation gives you two ways to set the baseline: medical evidence created before the aggravation
started, or "the earliest medical evidence created at any time between the onset of aggravation and
the receipt of medical evidence establishing the current level of severity." If you have no old records,
the earliest records made after the worsening began can still carry the claim. File it.
One narrow exception written into 3.310(a) itself: if the original disability was service connected
because of your tobacco use in service, a condition secondary to it is not granted under 3.310(a)
(38 CFR 3.300(c)). That is the only carve-out in the paragraph.
✅ Caused it, or made it worse. Both count.
The link
What VA actually needs from you
The word for the connection between the old condition and the new one is nexus.
- A current diagnosed condition — a doctor has named it in your records.
- An already service-connected disability.
- Evidence of a link between the two.
VA's own words on that link: "Usually we need medical records or medical opinions from health care
providers to support this link. In certain circumstances, we may also accept lay evidence, like a buddy
statement (VA Form 21-10210)." Read that twice. It says
usually — not always. If no doctor will
write you an opinion, that is not the end of the claim. A
lay or witness statement from your
spouse, a Family member, a battle buddy, or anyone who has watched the change in you is accepted evidence
in certain circumstances. File it and let VA weigh it.
You do not always have to buy a nexus letter. Where the record shows a current diagnosis, an
established service-connected disability, and an indication the two may be related, VA must provide a
medical examination or obtain a medical opinion at no cost to you when one is needed to decide the claim
— 38 CFR 3.159(c)(4). Go to the C&P exam VA schedules. Missing it can lose the claim.
✅ Usually medical. Not only medical.
Free money
The two things VA presumes
In these two places only, you do not have to prove the link at all.
1. Cardiovascular disease after a leg amputation — 38 CFR 3.310(c). This one is narrow. It applies
only if you are service connected for amputation of one lower extremity at or above the knee, or
amputations of both lower extremities at or above the ankles. Then ischemic heart disease or other
cardiovascular disease "shall be held to be the proximate result of the service-connected amputation."
Note the difference: one leg has to be at or above the knee; both legs qualify at or
above the ankles. It is not a general heart-disease presumption and it does not reach any other
amputation.
2. After a service-connected traumatic brain injury — 38 CFR 3.310(d). If you are service
connected for TBI, these are held to be the result of it, absent clear evidence to the contrary:
- Parkinsonism, including Parkinson's disease — after moderate or severe TBI
- Unprovoked seizures — after moderate or severe TBI
- Presenile dementia of the Alzheimer type, frontotemporal dementia, or dementia with Lewy bodies —
within 15 years of moderate or severe TBI
- Depression — within 3 years of a moderate or severe TBI, or within 12 months of a mild
TBI
- Diseases of hormone deficiency resulting from hypothalamo-pituitary changes — within 12 months of
moderate or severe TBI
Depression is the only one on that list reachable after a
mild TBI. The regulation carries its own
severity table — structural imaging, loss of consciousness, alteration of consciousness, post-traumatic
amnesia, Glasgow Coma Scale — and whether your TBI is graded mild or moderate-to-severe is what decides
which of these you get.
Missing the time window is not a denial. 38 CFR 3.310(d)(2) says these rules "shall not preclude a
finding of service connection" based on evidence of proximate causation outside those parameters. Outside
the window you are back to route one with a nexus opinion — which is still a live claim.
✅ Two presumptions. Both narrow. Both real.
The trap
Pyramiding — the rule that denies claims
38 CFR 4.14. You cannot be paid twice for the same thing.
The regulation: "the evaluation of the same disability under various diagnoses is to be avoided," and
"the evaluation of the same manifestation under different diagnoses are to be avoided." It names
"dyspnea, tachycardia, nervousness, fatigability" as examples of manifestations that "may result from many
causes" and must not be double-counted. It also warns that disability from injuries to the muscles,
nerves and joints of an extremity "may overlap to a great extent."
- If a symptom is already written into the rating formula for a condition you have, claiming it again as
a separate condition gets denied.
- The move is not to file a second claim. The move is to document that symptom and ask for an
increase on the rating you already hold.
- Stacking five overlapping claims in the same arm or leg can end with fewer ratings, not more.
✅ Same symptom, one payment.
Know the difference
A symptom is not a claim
VA rates diagnosed disabilities. It does not rate complaints.
- Get it diagnosed and named. VA eligibility runs on "a current illness or injury (known as a
condition)." Filing for "knee pain," "hip pain" or "neck pain" with nothing diagnosed behind it draws a
denial. Get it examined and get a name in the record.
- Fatigue, altered gait, mobility impairment, secondary joint pain, balance problems — filed as
conditions, these lose. Filed as evidence, they raise a rating or lead you to the diagnosis that pays.
- "Falls" is an event, not a disability. Claim the injury from the fall — the fractured
wrist, the head injury.
- "Medication side effects" is not a rateable thing. Name the condition the medication caused,
and claim that.
✅ Name the diagnosis. Then file.
Mental health
All of it is one rating — file it anyway
This is where I see the most wasted filings, and the most bad advice.
- A diagnosed mental health condition can be granted as secondary to a physical
service-connected disability under 38 CFR 3.310(a), with a link. That door is open.
- But VA normally pays one evaluation covering all of your service-connected mental disorders.
Depressed mood, anxiety, suspiciousness, panic attacks, chronic sleep impairment and mild memory loss are
already named symptoms inside the General Rating Formula for Mental Disorders at 38 CFR 4.130.
Filing PTSD plus depression plus anxiety plus insomnia does not produce four percentages.
So file it correctly instead of not filing. Ask for service connection of the new diagnosis
and for an increased evaluation — not for a second separate percentage. Getting the diagnosis
service connected still matters: it is how the single evaluation gets raised, it builds the record for
TDIU (being paid at the 100 percent rate because your disabilities keep you from working), and service
connection for the condition itself carries weight later, including for survivor benefits.
Two more things from the same part of the regulation. 38 CFR 4.126(b): VA "shall not assign an
evaluation solely on the basis of social impairment" — so social isolation on its own pays nothing.
38 CFR 4.126(c): a neurocognitive disorder is rated on the mental-disorder formula, but "neurologic
deficits or other impairments stemming from the same etiology (e.g., a head injury) shall be evaluated
separately and combined." For a veteran with TBI, that is separate money most people never ask for.
Sleep apnea is different. Sleep disturbance is a symptom inside the mental-health rating.
Sleep apnea is a physical condition with its own rating and its own diagnostic code, established
by a sleep study. That one is worth filing as a secondary with a nexus opinion.
✅ One rating. Still claim the diagnosis.
Spine and nerves
What is inside the back rating, and what is not
The spine codes cover more than most veterans realize — and less.
- Inside it already: limited range of motion and muscle spasm. The General Rating Formula for
Diseases and Injuries of the Spine (DC 5235-5243, which includes 5237, lumbosacral or cervical strain)
rates by measured forward flexion and ankylosis, "with or without symptoms such as pain (whether or not it
radiates), stiffness, or aching." Claiming those separately is pyramiding. Document them for an
increase.
- Rated separately, by the regulation's own direction: Note (1) under that formula says to
"evaluate any associated objective neurologic abnormalities, including, but not limited to, bowel or
bladder impairment, separately, under an appropriate diagnostic code." Nerve damage running down an arm
or a leg belongs in that category. That is a separate rating you are entitled to ask for.
- Headache from the neck. A separately diagnosed headache disorder secondary to a
service-connected cervical strain is a legitimate claim under 3.310(a), rated by analogy. Headache is not
one of the symptoms the spine formula lists, so it is not barred as pyramiding.
Name the nerve and name the leg. Radiculopathy is not one code. 38 CFR 4.124a carries separate
codes for the lower extremity — sciatic (8520), common peroneal (8521), anterior tibial (8523), tibial
(8524), posterior tibial (8525), femoral (8526), internal saphenous (8527). Upper-lumbar radiculopathy
(L2-L4) is the femoral nerve, not the sciatic. Different nerves in the same leg can carry their own
ratings; the same nerve cannot be rated twice, so do not file "radiculopathy" and "sciatica" as two
conditions. And when both legs are involved, the ratings combine with the bilateral factor,
38 CFR 4.26 — extra value nobody tells you about.
Muscle weakness in the affected leg is already inside the nerve rating. Balance is not — the
sciatic nerve criteria are written in terms of muscle function and foot drop, not balance. A diagnosed
vestibular or balance disorder has its own code and can be claimed.
✅ One nerve, one rating. Two nerves, two.
Feet, ankles, legs
The chain reaction claim
This is the most common secondary claim I help people see, and VA uses it as its own example.
- An altered gait, favoring one side, or a changed posture from a service-connected injury puts extra
stress on the feet, ankles, knees, hips, back and neck. Chronic conditions that develop from that stress
may be granted as secondary.
- VA's own illustration is exactly this shape: a service-connected knee injury causes a limp, and the
limp causes arthritis in the hip.
- Still not automatic. You need the diagnosis and the link — usually a medical opinion describing the
mechanism, the altered gait or the changed load.
Some of these conditions are not named in the rating schedule at all. Heel spurs and shin splints
are examples. That does not mean they cannot be rated — 38 CFR 4.20 allows rating an unlisted
condition "under a closely related disease or injury in which not only the functions affected, but the
anatomical localization and symptomatology are closely analogous." Do not let anyone tell you there is no
code, so there is no claim.
✅ Follow the limp. It goes somewhere.
Special rules
Two claims that need to be filed differently
Weight gain and obesity. Obesity by itself cannot be service connected. VA General Counsel
precedent opinion VAOPGCPREC 1-2017 holds that "obesity per se is not a 'disability' for purposes of
38 C.F.R. 3.310." The way it still helps you: obesity can be an intermediate step in a
chain. If a service-connected condition caused the weight gain, and the weight gain was a substantial
factor in causing a further condition, and that further condition would not have happened without it,
the further condition can be granted as secondary. Claim the downstream condition, not the weight.
Alcohol and substance use. 38 U.S.C. 1110 and 1131 both say "no compensation shall be paid if the
disability is a result of the veteran's own willful misconduct or abuse of alcohol or drugs," and
38 CFR 3.301(a) bars direct service connection for it. The doors that are still open: under
Allen v. Principi, 237 F.3d 1368 (Fed. Cir. 2001), an alcohol or substance use disorder can be
service connected as secondary to an already service-connected disability, with clear medical evidence
that the service-connected condition caused the abuse. Separately, 38 CFR 3.301(c)(2) provides that
"organic diseases and disabilities which are a secondary result of the chronic use of alcohol as a
beverage, whether out of compulsion or otherwise, will not be considered of willful misconduct origin,"
and 3.301(c)(3) says the same for chronic drug use and adds "infections coinciding with the injection of
drugs." The organ damage is a different and often better path than the use disorder. Ask an accredited
representative which one fits you.
And remember the mental-health rule above: drinking that is a symptom of a mental disorder you are
already rated for is paid inside that rating, not as a new claim.
✅ Closed door, open window.
Other doors
Two things that are not secondary claims
Dental damage. Under 38 CFR 3.381(b), treatable carious teeth, replaceable missing teeth, dental
and alveolar abscesses and periodontal disease are noncompensable — they are service connected for
outpatient dental treatment purposes only. 38 CFR 4.150 rates loss of teeth only where it comes
from loss of substance of the body of the maxilla or mandible, and only "where the lost masticatory
surface cannot be restored by suitable prosthesis"; those ratings "apply only to bone loss through trauma
or disease such as osteomyelitis." Acid erosion from reflux does not meet that. Where to go instead:
VA dental care eligibility under 38 CFR 17.161. Ask VA dental about Class VI — a dental condition
clinically determined to be complicating a medical condition currently under treatment. Class II(a)
covers a noncompensable dental condition resulting from combat wounds or service trauma; Class IV covers
veterans rated 100 percent schedular or paid at the 100 percent rate for unemployability.
If VA care itself caused the new disability. That is not a 3.310 secondary claim — it is a
38 U.S.C. 1151 claim. It compensates additional disability or death caused by VA "hospital care,
medical or surgical treatment, or examination" where there was "carelessness, negligence, lack of proper
skill, error in judgment, or similar instance of fault," or "an event not reasonably foreseeable." It is
paid as if the disability were service connected. Different claim, same paperwork trail — raise it with a
representative.
✅ Wrong claim type is still a denial.
How to file
Four steps, and one to do first
Do this before anything else: file an intent to file. VA Form 21-0966
tells VA you are coming, and VA says it "can secure the earliest possible effective date for any
retroactive payments you may be eligible to receive." If you apply online instead, VA says "your effective
date gets set automatically when you start filling out the form online — before you submit it."
The intent to file expires. Under 38 CFR 3.155(b), your completed application has to reach VA
within
one year of the intent to file for that earlier date to hold. Miss the year and it is gone.
- Get diagnosed. The new condition has to be named by a provider in your records.
- Get the link. A medical opinion saying the condition is "at least as likely as not" caused or
aggravated by your service-connected disability — or lay and buddy statements where medical evidence is
not available (VA Form 21-10210).
- File VA Form 21-526EZ,
Application for Disability Compensation and Related Compensation Benefits — the same form as an original
claim. Online at va.gov/disability/how-to-file-claim
is the faster route and sets your effective date as you start.
- Send the evidence. Records, imaging, treatment notes, the nexus opinion if you have one. Keep
records that show the change over time — the gait, the balance, the mobility, the pain.
There is no deadline to file a secondary claim. You can file any time after the primary condition
is service connected — five years later, twenty years later. But your effective date is tied to when VA
hears from you, not to when the condition started. That is the whole reason to put the intent to file in
first and build the evidence after. Waiting does not buy you a better date.
✅ Protect the date. Then build the file.
Do not quit
If it comes back denied
Denial is a normal first outcome on secondary claims. It is not the end.
- Higher-Level Review —
a more senior reviewer looks at the same evidence. File within 1 year of the date on your decision
letter.
- Board Appeal — to a Veterans
Law Judge. File within 1 year of the decision on your initial claim, Supplemental Claim, or
Higher-Level Review.
- Supplemental Claim — new
and relevant evidence. No filing deadline.
The Supplemental Claim trap. Read this part. There is no deadline to file a Supplemental
Claim, but there is a deadline to keep your money. Under 38 CFR 3.2500, if you keep the issue
continuously pursued by filing within one year of the decision notice, your effective date is fixed
by when VA received your original claim. File later than that year and "the effective date will be
fixed in accordance with the date entitlement arose, but will not be earlier than the date of receipt of
the supplemental claim." The door never closes. The back pay behind it does.
Contested claims are different. Where a claim is simultaneously contested — someone else is
claiming the same benefit — a Board Appeal must be requested within 60 days of the date on your
decision letter, not one year, and a contested claim is not eligible for Higher-Level Review at all.
✅ A denial is a step, not a verdict.
Your money
Who can help you, and what they may charge
VA accredits three kinds of representative, not one.
- An accredited Veterans Service Organization representative
- An accredited attorney
- An accredited claims agent
VA's own words: "the services an accredited VSO representative provides on your VA benefit claims are
always free. But an accredited attorney or claims agent can charge you fees." 38 CFR 14.636 puts it
squarely: "Recognized organizations (including their accredited representatives when acting as such) and
individuals recognized under § 14.630 of this part are not permitted to receive fees." A VSO
representative cannot charge you. Full stop. Find one at
va.gov/get-help-from-accredited-representative.
If you do hire an attorney or agent, know the fee rules. Under 38 CFR 14.636 they may charge only
after the agency of original jurisdiction has issued notice of an initial decision on the claim,
with a valid power of attorney and fee agreement on file. A fee not exceeding 20 percent of
past-due benefits is presumed reasonable. A fee exceeding 33 1/3 percent is presumed
unreasonable. Nobody who is not accredited by VA may represent you before VA or charge you for it at
all.
✅ Free help exists. Use it first.
Do not give up on it
Two things people quit over too early
A 0 percent rating is still a win. A secondary granted at 0 percent pays nothing today, but it
establishes service connection for that condition. That opens VA treatment for it and it is the
foundation for an increase later when the condition gets worse. Veterans see the zero and stop pursuing.
Do not.
Travel pay does not start at 30 percent. VA lists as its own separate qualifier: "You're traveling
for treatment of a service-connected condition, even if your VA disability rating is less than 30%." If
you are driving to VA for care on a condition VA has service connected, check
va.gov/health-care/get-reimbursed-for-travel-pay
whatever your percentage is.
And when you file the secondary, look at the primary at the same time. If the condition you are already
rated for has gotten worse, claim the increase alongside it instead of leaving it on the table.
✅ Zero percent is a foot in the door.