## Facts

- A Marine Corps veteran (active duty 1963–1967) sought service connection for a chronic low-back disability.
- He reported injuring his back during service when he fell in a landing craft and struck a steel lifting ring off the coast of Spain (1964 or 1965).
- Service records did not document a chronic back disorder, and the separation examination was negative for back pathology.
- He filed a claim in 2001 and submitted private treatment records showing a current low-back disability.
- Two private clinicians opined in 2001 that the current condition could be related to the reported in-service injury; the opinions were stated in tentative terms and relied in part on the veteran’s history.
- The regional office denied the claim without obtaining a VA examination; the Board accepted that an in-service injury occurred but denied service connection and found an examination unnecessary, characterizing the private opinions as speculative.

## Issues

1. When must VA provide a medical examination or obtain a medical opinion under 38 U.S.C. § 5103A(d) and 38 C.F.R. § 3.159(c)(4) in a service-connection claim?
2. What evidentiary showing satisfies the requirement that a disability “may be associated” with service so as to trigger VA’s duty to obtain an examination?

## Decision

- The court vacated the Board’s denial and remanded.
- It held the statutory and regulatory criteria requiring a VA medical examination were met.
- It concluded the Board erred by treating the duty-to-assist “indication” requirement as demanding near-conclusive nexus evidence.
- It directed VA to obtain a medical examination and nexus opinion.

## Legal Principles

- VA must provide a medical examination/opinion when four elements are satisfied: (1) competent evidence of a current disability or persistent/recurrent symptoms; (2) evidence of an in-service event, injury, or disease (or presumptive manifestation); (3) an indication that the disability or symptoms may be associated with service (or a service-connected disability); and (4) insufficient competent medical evidence to decide the claim.
- The third element (“may be associated”) establishes a low threshold; it requires only some indication of a possible link, not definitive proof of causation.
- Medical evidence characterized as speculative for purposes of proving nexus may still be sufficient, together with other evidence, to indicate a possible association and trigger an examination.
- If the record lacks an adequate medical opinion addressing nexus, the file may be insufficient to decide the claim, requiring VA to obtain an examination under § 5103A(d).

## Conclusion

The court held that, given evidence of a current disability, an accepted in-service injury, and tentative medical opinions suggesting a possible relationship, VA had a duty to provide a medical examination because the “may be associated” showing is minimal and the existing record was not medically adequate to decide nexus.


McLendon v. Nicholson, 20 Vet. App. 79 (2006)