Secondary service connection
Knee conditions secondary to an ankle condition: BVA grant rates and what wins
From 2017 to 2026, the Board of Veterans' Appeals decided knee claimed as secondary to an ankle condition in 1,754 decisions. It granted the issue in 18.3% of them, close to the 19.1% grant rate for all knee issues, denied it in 16.1%, and remanded it in 65.4%. Counting only decisions on the merits, 53.1% were granted.
From Board of Veterans' Appeals decisions: appeals, not VA's first decisions. About these numbers
Decisions
1,754
2017–2026
Granted
18.3%
All knee: 19.1%
Granted on the merits
53.1%
Granted ÷ (granted + denied)
Remanded
65.4%
Denied: 16.1%
At a glance
- Most often argued link: altered gait or overuse, named in 480 issues, 37.5% granted. Details
- Highest grant rate among links: stress, 40.0% of 35 issues. Details
- Causation only: 25.9% granted; when the decision discussed aggravation: 9.2%. Details
- Positive nexus opinion: 87.4% granted on the merits when in the record, 24.2% without. Details
- Private medical opinion: 72.2% granted on the merits when in the record, 26.3% without. Details
- Issues granted: 9.7% in 2017, 45.2% in 2026. Details
How these claims are argued
A secondary claim says an ankle 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)
9.2%
granted, of 1,034 issues (45.8% of all)
Causation only
caused by the disability, 3.310(a)
25.9%
granted, of 1,224 issues (54.2% of all)
| Medical link named | Issues | Granted |
|---|---|---|
Altered gait or overuse Granted “The Board found a causal relationship based on private medical opinions and treatment notes attributing the knee condition to the ankle injury and subsequent gait alterations.” A26011093 (2026) Denied “While the veteran is service-connected for the ankle, the most probative VA opinions found the knee disability less likely than not caused by or aggravated by the ankle condition, citing natural aging and lack of gait abnormality.” 25001667 (2025) | 480 | 37.5% |
Weight gain or obesity Granted “Multiple VA opinions inadequate for failing to address obesity as intermediate step or aggravation.” A25048080 (2025) Denied “The Board denied service connection, finding the evidence did not support a link to service, attributing the condition to age-related wear and tear, obesity, and post-service injuries.” 25014186 (2025) | 70 | 21.4% |
Nerve involvement Granted “Service connection for left knee strain was granted as secondary to service-connected residuals of right ankle fracture, loss of use of the left foot, and peripheral neuropathy of the right lower extremity.” A25110554 (2025) Denied “The veteran claims service connection for a left knee strain, asserting it is secondary to his service-connected right ankle disability, lower back disability, and bilateral lower extremity radiculopathy.” 25010527 (2025) | 39 | 17.9% |
Stress Granted “Altered gait from ankle disability stressed the knee” A26020933 (2026) Denied “Multiple VA examiners opined that the condition was less likely than not related to service, attributing it to aging and occupational stress, and found no chronic disorder or residuals from service.” 21045522 (2021) | 35 | 40.0% |
Chronic pain Granted “The Board found that the veteran's left knee disability, specifically a complex meniscus tear and cartilage degeneration causing chronic pain, was directly related to the chronic instability of the service-connected right ankle.” A24040677 (2024) Denied “The Board denied this claim, finding that the evidence showed only a noncompensable limitation of extension (5 degrees) and that using painful motion for a rating would constitute pyramiding, as a 10 percent rating for flexion...” A25105989 (2025) | 25 | 20.0% |
Based on words in the AI-written summary and reasons for each issue, not a reading of the full decision. 26.5% of the 2,258 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.
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 | 392 | 87.4% | 24.2% | +63.2 pts |
| Private medical opinion | 663 | 72.2% | 26.3% | +45.9 pts |
| Treating physician opinion | 99 | 81.8% | 49.6% | +32.2 pts |
| Favorable VA exam | 153 | 73.9% | 49.4% | +24.5 pts |
| Buddy statement | 54 | 70.0% | 52.6% | +17.4 pts |
| Combat service | 55 | 68.2% | 52.6% | +15.6 pts |
| Lay statement | 1,467 | 49.5% | 79.5% | −29.9 pts |
- The Board applied the benefit-of-the-doubt rule (38 CFR 3.102) in 80.4% of the decisions that granted knee.
- The Board found the veteran's statements credible in 30.8% of grants and 13.4% 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 | 1,268 | 51.0% | 62.1% | −11.0 pts |
| Unfavorable VA exam | 1,464 | 51.6% | 67.8% | −16.2 pts |
Recent knee decisions
Granted
Service-connected right ankle condition satisfies first two elements of secondary SC.; Conflicting medical opinions regarding nexus between ankle and knee conditions.; Private opinions found more persuasive than VA opinions.; Evidence found to be in equipoise, conferring benefit of doubt.
Conflicting medical opinions on nexus; Benefit of the doubt applied due to equipoise; Later VA exam found at least as likely as not secondary
Secondary to service-connected left ankle disability; Pain causes functional impairment of earning capacity; Competent lay testimony regarding symptoms and work impact
Denied
Right knee disability not secondary to right ankle disability; Criteria for service connection not met
No service connection for left knee disorder; Claimed as secondary to right ankle disorder; Theory of entitlement raised after initial rating decision
Failure to report for VA examination without good cause.; No competent medical evidence of nexus to service.; Evidence persuasively weighs against causation by in-service locking, toxic exposures, or left ankle disability.
Knee conditions secondary to an ankle condition: outcomes by year
| Year | Issues decided | Granted | Denied | Remanded | Other |
|---|---|---|---|---|---|
| 2017 | 155 | 9.7% | 16.1% | 70.3% | 3.9% |
| 2018 | 243 | 14.4% | 25.1% | 58.8% | 1.6% |
| 2019 | 215 | 14.9% | 16.3% | 67.4% | 1.4% |
| 2020 | 264 | 12.5% | 19.7% | 67.0% | 0.8% |
| 2021 | 273 | 10.6% | 14.7% | 74.7% | 0.0% |
| 2022 | 277 | 14.8% | 12.6% | 72.6% | 0.0% |
| 2023 | 282 | 21.3% | 14.2% | 63.5% | 1.1% |
| 2024 | 248 | 26.2% | 7.3% | 66.1% | 0.4% |
| 2025 | 217 | 29.5% | 16.6% | 53.5% | 0.5% |
| 2026 | 84 | 45.2% | 7.1% | 47.6% | 0.0% |
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.
Why the Board granted or denied knee
Most common reasons in grants
- Caused by the service-connected disability66
- Service connection established37
- Current diagnosis established27
- Aggravated by the service-connected disability17
- Secondary service connection granted5
- VA examiner: less likely than not related to service4
- New and material evidence submitted4
- Private medical opinion found persuasive3
Most common reasons in denials
- VA examiner: less likely than not related to service58
- No in-service complaints, treatment or diagnosis43
- Preponderance of the evidence against the claim31
- Service records negative or silent29
- Aggravated by the service-connected disability15
- No current diagnosis12
- Current diagnosis established10
- Caused by the service-connected disability9
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.
Background
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.
- An ankle condition is already service connected.
- Medical evidence linking them (a nexus opinion): knee was caused by an ankle 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).
How VA rates knee
Once service connection is granted, VA assigns a disability rating from the rating schedule, 38 CFR 4.71a. The Board rates knee under 8 diagnostic codes, shown here in the order it used them most. The rating is the same whether the condition is service connected directly or as secondary to another disability.
5256 Knee, ankylosis of
| Rating | Criteria |
|---|---|
| 60% | Extremely unfavorable, in flexion at an angle of 45° or more |
| 50% | In flexion between 20° and 45° |
| 40% | In flexion between 10° and 20° |
| 30% | Favorable angle in full extension, or in slight flexion between 0° and 10° |
5257 Knee, other impairment of
| Rating | Criteria |
|---|---|
| Recurrent subluxation or instability | |
| 30% | Unrepaired or failed repair of complete ligament tear causing persistent instability, and a medical provider prescribes both an assistive device (e.g., cane(s), crutch(es), walker) and bracing for ambulation |
| One of the following | |
| (a) Sprain, incomplete ligament tear, or repaired complete ligament tear causing persistent instability, and a medical provider prescribes a brace and/or assistive device (e.g., cane(s), crutch(es), walker) for ambulation. | |
| 20% | (b) Unrepaired or failed repair of complete ligament tear causing persistent instability, and a medical provider prescribes either an assistive device (e.g., cane(s), crutch(es), walker) or bracing for ambulation |
| 10% | Sprain, incomplete ligament tear, or complete ligament tear (repaired, unrepaired, or failed repair) causing persistent instability, without a prescription from a medical provider for an assistive device (e.g., cane(s), crutch(es), walker) or bracing for ambulation |
| Patellar instability | |
| 30% | A diagnosed condition involving the patellofemoral complex with recurrent instability after surgical repair that requires a prescription by a medical provider for a brace and either a cane or a walker |
| 20% | A diagnosed condition involving the patellofemoral complex with recurrent instability after surgical repair that requires a prescription by a medical provider for one of the following: A brace, cane, or walker |
| 10% | A diagnosed condition involving the patellofemoral complex with recurrent instability (with or without history of surgical repair) that does not require a prescription from a medical provider for a brace, cane, or walker |
- Note (1): For patellar instability, the patellofemoral complex consists of the quadriceps tendon, the patella, and the patellar tendon.
- Note (2): A surgical procedure that does not involve repair of one or more patellofemoral components that contribute to the underlying instability shall not qualify as surgical repair for patellar instability (including, but not limited to, arthroscopy to remove loose bodies and joint aspiration).
5258 Cartilage, semilunar, dislocated, with frequent episodes of “locking,” pain, and effusion into the joint
| Rating | Criteria |
|---|---|
| 20% | Cartilage, semilunar, dislocated, with frequent episodes of “locking,” pain, and effusion into the joint |
5259 Cartilage, semilunar, removal of, symptomatic
| Rating | Criteria |
|---|---|
| 10% | Cartilage, semilunar, removal of, symptomatic |
Also in this range: 5260 Leg, limitation of flexion of; 5261 Leg, limitation of extension of; 5262 Tibia and fibula, impairment of; 5263 Genu recurvatum (acquired, traumatic, with weakness and insecurity in weight-bearing objectively demonstrated). See 38 CFR 4.71a for their levels.
Text of 38 CFR 4.71a as of Feb 27, 2026. Confirm the current text at the source before relying on it.
See all knee decisions, direct and secondary.
Other conditions secondary to an ankle condition
Knee conditions secondary to other conditions
See all conditions secondary to an ankle 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 an ankle 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.
Where this data comes from
- Claim
- Regional office decides
- Veteran appeals
- Board decides
- Granted · Denied · Remanded: back to the regional office
Board of Veterans' Appeals decisions show how VA's highest review body applies 38 CFR and weighs evidence on contested claims.
Each one is an appeal: a regional office decided the claim first, and the veteran appealed. So these rates describe the Board, not a veteran's odds at the regional office, where most claims are decided and whose decisions are not public.
More on what Board decisions can and cannot tell you