Secondary service connection
Knee conditions secondary to a back condition: BVA grant rates and what wins
From 2017 to 2026, the Board of Veterans' Appeals decided knee claimed as secondary to a back condition in 2,251 decisions. It granted the issue in 12.3% of them, below the 19.1% grant rate for all knee issues, denied it in 20.3%, and remanded it in 66.6%. Counting only decisions on the merits, 37.8% were granted.
Decisions
2,251
2017–2026
Granted
12.3%
All knee: 19.1%
Granted on the merits
37.8%
Granted ÷ (granted + denied)
Remanded
66.6%
Denied: 20.3%
See all knee decisions, direct and secondary.
Knee conditions secondary to a back condition: outcomes by year
| Year | Issues decided | Granted | Denied | Remanded | Other |
|---|---|---|---|---|---|
| 2017 | 220 | 11.8% | 27.3% | 58.6% | 2.3% |
| 2018 | 279 | 8.6% | 29.7% | 58.4% | 3.2% |
| 2019 | 299 | 9.4% | 18.1% | 72.6% | 0.0% |
| 2020 | 368 | 11.7% | 20.4% | 65.5% | 2.4% |
| 2021 | 376 | 6.4% | 29.5% | 63.8% | 0.3% |
| 2022 | 388 | 10.1% | 12.6% | 75.8% | 1.5% |
| 2023 | 388 | 13.7% | 18.0% | 67.0% | 1.3% |
| 2024 | 353 | 14.7% | 13.6% | 71.4% | 0.3% |
| 2025 | 274 | 21.5% | 19.7% | 58.0% | 0.7% |
| 2026 | 140 | 22.1% | 10.0% | 67.1% | 0.7% |
Each row counts issues (each condition the Board decided), so the shares add up to 100%. Other: dismissed, withdrawn or no clear outcome. Years with fewer than 20 issues are left out.
Evidence in granted and denied knee decisions
For each kind of supporting evidence: how often the Board granted the knee issue on the merits when the decision mentioned it, compared with decisions that did not. These are associations, not causes, and evidence is recorded per decision, not per issue.
| In the record | Decisions | Granted when present | When absent | Difference |
|---|---|---|---|---|
| Positive nexus opinion | 422 | 83.5% | 15.9% | +67.6 pts |
| Favorable VA exam | 221 | 74.3% | 31.1% | +43.2 pts |
| Private medical opinion | 713 | 55.7% | 22.9% | +32.8 pts |
| Treating physician opinion | 116 | 61.7% | 35.7% | +26.0 pts |
| Lay statement | 1,870 | 33.4% | 67.7% | −34.3 pts |
- The Board applied the benefit-of-the-doubt rule (38 CFR 3.102) in 78.3% of the decisions that granted knee.
- The Board found the veteran's statements credible in 27.1% of grants and 11.8% of denials.
Negative evidence in the record
An unfavorable exam or a negative nexus opinion often sits in the same record as favorable evidence, and the Board weighs them against each other. So these rows show how often knee was still granted when the record contained the negative item, not that the item helped.
| In the record | Decisions | Granted when present | When absent | Difference |
|---|---|---|---|---|
| Negative nexus opinion | 1,567 | 33.4% | 54.2% | −20.8 pts |
| Unfavorable VA exam | 1,857 | 35.1% | 56.4% | −21.3 pts |
How these claims are argued
A secondary claim says a back condition caused knee or made it worse, and names how. Below: whether the Board's decision discussed aggravation, and the medical link each decision names, with how often those issues were granted.
Aggravation discussed
made worse by the disability, 3.310(b)
6.7%
granted, of 1,349 issues (43.7% of all)
Causation only
caused by the disability, 3.310(a)
16.6%
granted, of 1,736 issues (56.3% of all)
| Medical link named | Issues | Granted |
|---|---|---|
Altered gait or overuse Granted “A VA examiner in October 2024 provided a positive nexus opinion, stating that lumbar spine issues could cause abnormal gait and strain on the ankle, establishing a pathophysiological relationship.” 26001978 (2026) Denied “Inconsistent gait documentation and lack of progression evidence.” A26001805 (2026) | 385 | 28.1% |
Nerve involvement Granted “Service connection for right knee instability was granted as secondary to the Veteran's service-connected lumbar degenerative disc disease, left knee disabilities, and lower extremity radiculopathy.” A25022064 (2025) Denied “Examiner attributed symptoms to low back disorder and radiculopathy..” 26004881 (2026) | 220 | 8.6% |
Weight gain or obesity Granted “Obesity as intermediate step.” 26003891 (2026) Denied “VA examiner opined current arthritis likely due to aging and obesity..” A25020209 (2025) | 129 | 12.4% |
Chronic pain Granted “The Veteran's lumbar spine condition caused chronic pain and aggravated the left knee, leading to DJD.” A26004803 (2026) Denied “Private records also indicated flexion limited to 70 degrees due to pain.” A25069290 (2025) | 56 | 25.0% |
Stress Granted “Service connection for left knee strain was granted on a secondary basis to the service-connected lumbar spine disability, based on a private medical opinion that found the strain likely due to imbalanced stress on joints from lumbar pain.” A26005954 (2026) Denied “The veteran sought service connection for a right knee disability, claiming it was directly related to in-service injuries and pain, secondarily to service-connected low back disability and right tibia stress fracture, and due to...” 1722866 (2017) | 40 | 52.5% |
Based on words in the AI-written summary and reasons for each issue, not a reading of the full decision. 23.4% of the 3,085 issues name at least one medical link; the rest only say “secondary to” the disability. One issue can name several links. Granted is the share of those issues granted (remands count as not granted). A link named in a denial was often the argument the Board rejected.
Why the Board granted or denied knee
Most common reasons in grants
- Caused by the service-connected disability66
- Current diagnosis established28
- Service connection established20
- Aggravated by the service-connected disability15
- Continuity of symptomatology since service5
- Criteria for service connection met5
- New and material evidence received to reopen claim3
- New and material evidence received3
Most common reasons in denials
- No in-service complaints, treatment or diagnosis88
- VA examiner: less likely than not related to service86
- Service records negative or silent45
- Preponderance of the evidence against the claim40
- Aggravated by the service-connected disability38
- No current diagnosis26
- Caused by the service-connected disability16
- No continuity of symptomatology16
Numbers are decisions that gave the reason. Reasons are short phrases extracted by AI from each decision; common wordings of the same reason are grouped. Benefit of the doubt is reported above.
Recent knee decisions
Granted
Private medical opinion provided favorable nexus; Equipoise resolved in Veteran's favor; Secondary to service-connected lumbar spine disability
Favorable finding by RO adopted by Board; Secondary to service-connected lumbar spine disability
Private medical opinion found right knee osteoarthritis secondary to altered biomechanics from service-connected lumbar spine, left knee, and bilateral plantar fasciitis.; Opinion cited medical literature supporting the link between gait disturbances and adjacent joint stress.; Veteran diagnosed with right knee osteoarthritis; no in-service complaints noted.
Denied
Isolated in-service treatment for left knee pain with no further documentation or diagnosis.; March 2017 VA examiner opinion found less likely than not related to service.; Examiner noted mild degenerative arthritis consistent with aging/occupation.; Examiner attributed symptoms to low back disorder and radiculopathy.
No in-service complaints, treatment, or diagnosis of left knee disorder in STRs.; Separation exam showed no left knee issues; veteran denied relevant symptoms.; VA addendum opinion found osteoarthritis less likely than not due to service-connected back disability.
Service treatment records normal for left knee.; No in-service complaints or treatment for left knee.; Post-service treatment began over 40 years after service.; VA examiners opined less likely than not related to service.; Private opinions given minimal weight due to lack of in-service nexus and post-service delay.
What VA needs to grant a secondary claim
Secondary service connection means VA disability benefits for a condition caused or made worse by a disability that is already service connected (38 CFR 3.310). The claim needs three things:
- A current diagnosis of knee.
- A back condition is already service connected.
- Medical evidence linking them (a nexus opinion): knee was caused by a back condition (3.310(a)), or was made worse beyond its natural progress by it (aggravation, 3.310(b)).
VA's procedures for these claims are in M21-1 V.ii.2.D. When the evidence for and against is about even, VA must decide in the veteran's favor (38 CFR 3.102).
Other conditions secondary to a back condition
- Paralysis of sciatic nerve secondary to a back condition325 decisions · 57.8% granted
- Radiculopathy secondary to a back condition1,181 decisions · 49.9% granted
- Major depressive disorder secondary to a back condition770 decisions · 47.4% granted
- Paralysis of sciatic nerve or external popliteal nerve secondary to a back condition2,436 decisions · 38.7% granted
- Sleep apnea secondary to a back condition1,166 decisions · 38.2% granted
- Ulnar nerve paralysis secondary to a back condition628 decisions · 34.6% granted
- Peripheral nerve conditions secondary to a back condition307 decisions · 32.2% granted
- Peripheral nerve disorders secondary to a back condition1,204 decisions · 27.8% granted
- Erectile dysfunction secondary to a back condition619 decisions · 27.6% granted
- Degenerative arthritis of the spine secondary to a back condition679 decisions · 23.7% granted
- Urinary incontinence secondary to a back condition408 decisions · 22.8% granted
- Hypertension secondary to a back condition330 decisions · 20.0% granted
- Migraine secondary to a back condition347 decisions · 18.7% granted
- Hip impairment secondary to a back condition1,856 decisions · 13.6% granted
- Ankle impairment secondary to a back condition322 decisions · 11.2% granted
- Cervical spine limitation of motion secondary to a back condition1,553 decisions · 8.8% granted
- Shoulder impairment secondary to a back condition647 decisions · 7.3% granted
- Foot impairment secondary to a back condition354 decisions · 6.2% granted
Knee conditions secondary to other conditions
See all conditions secondary to a back condition or knee conditions as a primary or secondary condition.
Rules that apply to secondary knee claims
- 38 CFR 3.310
Secondary service connection and aggravation
Read it in VA Law Explorer - M21-1 V.ii.2.D
Secondary service connection and aggravation of non-service-connected disabilities
Read it in VA Law Explorer - 38 CFR 3.102
Reasonable doubt (benefit of the doubt)
Read it in VA Law Explorer - 38 CFR 4.71a · DC 5256-5263
Schedule of ratings: musculoskeletal system (knee and leg)
Read it in VA Law Explorer - M21-1 V.iii.1.B.4
Knee: instability, meniscus, genu recurvatum, and when to rate them separately from limited motion
Read it in VA Law Explorer - M21-1 V.iii.1.A
Painful motion and functional loss (38 CFR 4.59, DeLuca, Mitchell, Correia), incl. knee replacement
Read it in VA Law Explorer
Research your knee case
Narrow by year, judge, evidence or secondary condition, read the decisions, and export a research memo.
How these numbers are calculated
- Counts decisions in which the Board decided a knee issue claimed as secondary to a back condition, by the outcome of that issue.
- The primary disability is read from the decision text ("secondary to …") and grouped by name, so spellings such as "PTSD" and "posttraumatic stress disorder" count together.
- Secondary claims also include aggravation of a non-service-connected condition by a service-connected one (38 CFR 3.310(b)).
- The data comes from CaseScribe's AI extraction of public BVA decisions (2017–2026) and can contain errors. It is updated automatically as new decisions are added.