Citation Nr: 1326190 Decision Date: 08/16/13 Archive Date: 08/26/13 DOCKET NO. 10-30 464 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in St. Petersburg, Florida THE ISSUE Entitlement to service connection for degenerative joint disease of the left knee, including as secondary to a service-connected right knee disability, status post total knee arthroplasty (TKA). REPRESENTATION Veteran represented by: Disabled American Veterans ATTORNEY FOR THE BOARD C. Kedem, Counsel INTRODUCTION The Veteran served on active duty from October 1957 to April 1969 and had prior active service that has not been verified. He appealed to the Board of Veterans' Appeals (Board/BVA) from an August 2009 rating decision of a Department of Veterans Affairs (VA) Regional Office (RO). A hearing at the RO before a Veterans Law Judge of the Board (Travel Board hearing) was scheduled for July 23, 2012. However, the Veteran did not appear for the hearing, so was a "no show", and has not provided any good-cause explanation for his absence or requested to reschedule the hearing. Consequently, his Travel Board hearing request is deemed withdrawn. See 38 C.F.R. § 20.704(d) (2012). In September 2012 the Board reopened the claim of entitlement to service connection for a right knee disability, which had been previously considered and denied in a rating decision that had become final and binding. 38 U.S.C.A. § 7105 (West 2002); 38 C.F.R. §§ 3.104(a), 3.160(d), 20.1103 (2012). So, in reopening the claim, the Board determined there was new and material evidence since that earlier decision denying that claim. 38 C.F.R. § 3.156. The Board then proceeded, however, to remand this claim and the additional claim of entitlement to service connection for a left knee disability, since alleged to be secondary to the right knee disability, for further procedural and evidentiary development. The additional development of these claims subsequently was completed satisfactorily. See Dyment v. West, 13 Vet. App. 141, 146-47 (1999) (another remand not required under Stegall v. West, 11 Vet. App. 268, 271 (1998), where the Board's remand instructions were substantially complied with), aff'd, Dyment v. Principi, 287 F.3d 1377 (Fed. Cir. 2002). Indeed, in an April 2013 rating decision on remand, the Appeals Management Center (AMC) granted the claim of entitlement to service connection for a right knee disability, status postoperative TKA. The AMC assigned an initial 10 percent rating for this right knee disability retroactively effective from April 30, 2009, and a higher 30 percent rating for this disability as of January 17, 2013. Since the Veteran has not, in response, separately appealed either these initial ratings or effective dates, this claim is no longer at issue. See Grantham v. Brown, 114 F.3d 1156 (Fed. Cir. 1997) (where an appealed claim for service connection is granted during the pendency of the appeal, a second Notice of Disagreement (NOD) thereafter must be timely filed to initiate appellate review of the claim concerning "downstream" issues such as the compensation level assigned for the disability and effective date). So only the claim concerning whether he also is entitled to service connection for his left knee disability remains since the AMC continued to deny this other claim. Please also note this appeal has been advanced on the Board's docket pursuant to 38 C.F.R. § 20.900(c) (2012). 38 U.S.C.A. § 7107(a)(2) (West 2002). FINDING OF FACT The degenerative joint disease (arthritis) affecting the Veteran's left knee is not shown to have initially manifested during his active military service or even for many ensuing years following the conclusion of his service, and it is not otherwise shown to be secondarily related to his service by way of a service-connected disability, in particular his right knee disability. CONCLUSION OF LAW The degenerative joint disease affecting his left knee was not incurred in or aggravated by his service, may not be presumed to have been, and is not proximately due to, the result of, or aggravated by a service-connected disability, especially his right knee disability. 38 U.S.C.A. §§ 1101, 1110, 1112, 1113, 1131, 1137, 5107(b) (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309, 3.310 (2012). REASONS AND BASES FOR FINDING AND CONCLUSION Veterans Claims Assistance Act of 2000 (VCAA) The VCAA and implementing regulations impose obligations on VA to provide those claiming entitlement to VA benefits with notice and assistance with their claims upon receipt of a complete or substantially complete application. 38 U.S.C.A. §§ 5102, 5103, 5103A, 5107, 5126 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.102, 3.156(a), 3.326(a) (2012). The notice requirements of VCAA require VA to notify the claimant of the 1) information or evidence that is necessary to substantiate the claim; 2) of the necessary information or evidence the claimant is to provide; and 3) of the necessary information or evidence that VA will attempt to obtain on the claimant's behalf. See Quartuccio v. Principi, 16 Vet. App. 183, 187 (2002). But the so-called "fourth element" of the notice requirement requesting the claimant to provide any evidence in the claimant's possession pertaining to the claim was removed from the language of 38 C.F.R. § 3.159(b)(1). See 73 Fed. Reg. 23,353-356 (April 30, 2008). In Dingess v. Nicholson, 19 Vet. App. 473 (2006), the U. S. Court of Appeals for Veterans Claims (Court/CAVC) held that the notice requirements of 38 U.S.C.A. § 5103(a) and 38 C.F.R. § 3.159(b) apply to all five elements of a service-connection claim: (1) Veteran status; (2) existence of a disability; (3) a connection between the Veteran's service and the disability; but also the "downstream" (4) degree of disability, i.e., disability rating; and (5) effective date. Ideally, this notice should precede the initial adjudication of the claim. See Pelegrini v. Principi, 18 Vet. App. 112, 120-21 (2004) (Pelegrini II). However, both the U. S. Court of Appeals for the Federal Circuit (Federal Circuit Court) and Veterans Court (CAVC) have clarified that, even when notice is not provided prior to initially adjudicating a claim or, if provided, was inadequate or incomplete, VA need only provide all necessary notice, give the Veteran opportunity to submit additional evidence and/or argument in response, and then readjudicate the claim, including in a statement of the case (SOC) or supplemental SOC (SSOC), such that the essential fairness of the adjudication, as a whole, is unaffected because he is still provided meaningful opportunity to participate effectively in the adjudication of the claim. See Mayfield v. Nicholson, 499 F.3d 1317, 1323 (Fed. Cir. 2007) (Mayfield IV) (holding that an SOC or SSOC can constitute a "readjudication decision" that complies with all applicable due process and notification requirements if adequate VCAA notice is provided prior to the SOC or SSOC). As a matter of law, the provision of adequate VCAA notice prior to a readjudication "cures" any timing problem associated with inadequate notice or the lack of notice prior to an initial adjudication. See also Prickett v. Nicholson, 20 Vet. App. 370, 376 (2006). In Shinseki v. Sanders, 129 S. Ct. 1696 (2009), the U. S. Supreme Court made clear that VCAA notice errors, even when shown to have occurred, are not presumptively prejudicial, instead, must be judged on an individual case-by-case basis. Moreover, as the pleading party attacking the agency's decision, the Veteran, not VA, has this burden of proof of not only establishing error but also, above and beyond that, of showing how it is unduly prejudicial, meaning outcome determinative of his claim. Here, in a February 2013 letter, the RO provided notice to the Veteran regarding what information and evidence was needed to substantiate his claim of entitlement to service connection for his left knee disability, including on a secondary basis, as well as apprised him of the information and evidence he needed to submit versus that VA would obtain for him. The notice also included the required information concerning how downstream disability ratings and for effective dates are assigned. Moreover, his claim has been readjudicated since providing this required notice, so the timing defect in the provision of this notice, since it did not precede the initial adjudication of the claim, has been rectified ("cured"). The Board also is satisfied that VA has made the required efforts to obtain all relevant records and evidence. The record on appeal contains his service treatment records (STRs), service personnel records (SPRs), post-service private medical records, his personal lay statements, and VA examination reports. When, as here, VA undertakes to provide a VA examination or obtain a VA opinion, it must ensure the examination or opinion is adequate. Barr v. Nicholson, 21 Vet. App. 303, 312 (2007). The Board finds that the medical opinions obtained in this case, especially when considered in the aggregate, are adequate to decide this claim. The opinions provided considered all of the pertinent evidence of record, including the Veteran's statements and recounted history of his disability, and provided the required explanatory rationale for the opinions stated, which is where most of the probative value of an opinion is derived. See Neives-Rodriguez v. Peake, 22 Vet. App. 295 (2008). Accordingly, the Board finds that VA's duty to assist with respect to obtaining a VA examination or opinion has been met. 38 U.S.C.A. § 5103A(d)(2); 38 C.F.R. § 3.159(c)(4). For these reasons, the Board finds that VA has fulfilled its duty-to-notify-and-assist obligations as concerning this claim, so may proceed to adjudicating the merits of this claim. Standard of Review After the evidence has been assembled, it is the Board's responsibility to evaluate the entire record. 38 U.S.C.A. § 7104(a) (West 2002). When there is an approximate balance of evidence regarding the merits of an issue material to the determination of the matter, the benefit of the doubt in resolving each such issue shall be given to the claimant. 38 U.S.C.A. § 5107; 38 C.F.R. §§ 3.102, 4.3 (reasonable doubt to be resolved in Veteran's favor). In Gilbert v. Derwinski, 1 Vet. App. 49, 53 (1990), the Court (CAVC) stated that "a Veteran need only demonstrate that there is an 'approximate balance of positive and negative evidence' in order to prevail." To deny a claim on its merits, the preponderance of the evidence must be against the claim. See Alemany v. Brown, 9 Vet. App. 518, 519 (1996), citing Gilbert, 1 Vet. App. at 54. Governing Statutes, Regulations and Case Law Service connection is granted for disability resulting from disease or injury incurred in or aggravated by active military, naval, or air service in the line of duty. 38 U.S.C.A. §§ 1110, 1131; 38 C.F.R. §§ 3.303(a), 3.306 (2012). For the showing of chronic disease in service, there is required a combination of manifestations sufficient to identify the disease entity, and sufficient observation to establish chronicity at the time. With chronic disease as such in service, subsequent manifestations of the same chronic disease at any later date, however remote, are service connected, unless clearly attributable to intercurrent causes. If a condition noted during service is not shown to be chronic, or this is legitimately questionable, then generally a showing of continuity of symptoms after service is required to support the claim. 38 C.F.R. § 3.303(b). Service connection is permissible for any disease diagnosed after discharge, when the evidence, including that pertinent to service, establishes the disease was incurred in service. 38 C.F.R. § 3.303(d). So establishing entitlement to service connection generally requires having: (1) competent and credible evidence confirming the Veteran has the claimed disability or, at the very least, showing he has at some point since the filing of his claim; (2) competent and credible evidence of in-service incurrence or aggravation of a relevant disease or an injury; and (3) competent and credible evidence of a relationship or correlation between the disease or injury in service and the presently claimed disability - the so-called "nexus" requirement. See Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004). Certain conditions like arthritis are considered to be chronic (permanent), per se, and therefore will be presumed to have been incurred in service if manifested to a compensable degree (generally meaning to at least 10-percent disabling) within the year after service. This presumption, however, is rebuttable by affirmative evidence to the contrary. See 38 U.S.C.A. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309(a). Moreover, a Veteran may only show continuity of symptomatology following the conclusion of his military service to alternatively establish the required linkage between his service and current disability under 38 C.F.R. § 3.303(b) if he has one of the "chronic diseases" specifically enumerated in 38 C.F.R. § 3.309(a). Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). Arthritis is indeed one of those diseases identified in this VA regulation, however. 38 C.F.R. § 3.309(a). Service connection also may be granted for disability that is proximately due to or the result of a service-connected disability. 38 C.F.R. § 3.310(a). When service connection is thus established for a secondary condition, the secondary condition shall be considered a part of the original condition. Id; see also Harder v. Brown, 5 Vet. App. 183, 187 (1993). This controlling regulation has been interpreted to permit granting service connection not only for disability caused by a service-connected disability, but also for the degree of disability (albeit only that degree) alternatively resulting from aggravation of a non-service-connected disability by a service-connected disability. 38 C.F.R. § 3.310(b); Allen v. Brown, 7 Vet. App. 439, 448 (1995). To prevail on the issue of secondary service causation, the record must show (1) evidence of current disability, (2) evidence of a service-connected disability, and (3) evidence establishing the required nexus between the current disability and the service-connected disability. Wallin v. West, 11 Vet. App. 509, 512 (1998); Reiber v. Brown, 7 Vet. App. 513, 516-17 (1995). Competency of evidence differs from weight and credibility. Competency is a legal concept determining whether testimony may be heard and considered by the trier of fact, whereas credibility is a factual determination going to the probative value of the evidence to be made after the evidence has been admitted. Rucker v. Brown, 10 Vet. App. 67 (1997); Layno v. Brown, 6 Vet. App. 465 (1994); Cartwright v. Derwinski, 2 Vet. App. 24 (1991) (although interest may affect the credibility of testimony, it does not affect competency to testify). A Veteran is competent to report symptoms because this requires only personal knowledge, not medical expertise, as it comes to him through his senses. See Layno, 6 Vet. App. 465. The Board is charged with the duty to assess the credibility and weight given to evidence. Wensch v. Principi, 15 Vet. App. 362, 367 (2001); Wood v. Derwinski, 1 Vet. App. 190, 193 (1991). In weighing credibility, VA may consider interest, bias, inconsistent statements, bad character, internal inconsistency, facial plausibility, self interest, consistency with other evidence of record, malingering, desire for monetary gain, and demeanor of the witness. Caluza v. Brown, 7 Vet. App. 498 (1995). The Board may weigh the absence of contemporaneous medical evidence against the lay evidence in determining credibility, but the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence. Buchanan v. Nicholson, 451 F.3d 1331 (Fed. Cir. 2006). Generally, the degree of probative value that may be attributed to a medical opinion issued by a VA or private treatment provider takes into account such factors as its thoroughness and degree of detail, and whether there was review of the Veteran's claims file, although mere review of the claims file is not determinative of the opinion's probative value. Prejean v. West, 13 Vet. App. 444, 448-9 (2000). Also significant is whether the examining medical provider had a sufficiently clear and well-reasoned rationale, as well as a basis in objective supporting clinical data. Bloom v. West, 12 Vet. App. 185, 187 (1999); Hernandez-Toyens v. West, 11 Vet. App. 379, 382 (1998); see also Claiborne v. Nicholson, 19 Vet. App. 181, 186 (2005) (rejecting medical opinions that did not indicate whether the physicians actually examined the Veteran, did not provide the extent of any examination, and did not provide any supporting clinical data). The Court has held that a bare conclusion, even one reached by a health care professional, is not probative without a factual predicate in the record. Miller v. West, 11 Vet. App. 345, 348 (1998). Medical evidence that is speculative, general or inconclusive in nature cannot support a claim. Obert v. Brown, 5 Vet. App. 30, 33 (1993); see also Beausoleil v. Brown, 8 Vet. App. 459, 463 (1996); Libertine v. Brown, 9 Vet. App. 521, 523 (1996). A physician's statement framed in terms such as "may" or "could" is not probative because this is tantamount to just as well saying "may not" or "could not". See Warren v. Brown, 6 Vet. App. 4, 6 (1993). A significant factor to be considered for any opinion, as mentioned, is the accuracy of the factual predicate, regardless of whether the information supporting the opinion is obtained by review of medical records or lay reports of injury, symptoms and/or treatment. See Harris v. West, 203 F.3d 1347, 1350-51 (Fed. Cir. 2000) (examiner opinion based on accurate lay history deemed competent medical evidence in support of the claim); Kowalski v. Nicholson, 19 Vet. App. 171, 177 (2005) (holding that a medical opinion cannot be disregarded solely on the rationale that the medical opinion was based on history given by the Veteran). Rather, as the Court further explained in Coburn v. Nicholson, 19 Vet. App. 427 (2006), reliance on a Veteran's statements renders a medical report not credible only if the Board rejects the statements of the Veteran as lacking credibility. But see, too, Reonal v. Brown, 5 Vet. App. 458, 461 (1993) (holding that the Board may reject a medical opinion based on an inaccurate factual basis). In deciding this claim, the Board has reviewed all of the evidence in the Veteran's claims file - both his physical claims file and electronic ("Virtual VA") file. Although the Board has an obligation to provide adequate reasons and bases supporting this decision, there is no requirement that the evidence submitted by him or obtained on his behalf be discussed in exhaustive detail. Rather, the Board's analysis below will focus specifically on what evidence is needed to substantiate the claim and what the evidence in the claims file shows, or fails to show, with respect to the claim. Gonzales v. West, 218 F.3d 1378, 1380-81 (Fed. Cir. 2000); Timberlake v. Gober, 14 Vet. App. 122, 128-30 (2000). Factual Background The primary basis of the Veteran's claim is that his left knee disability is attributable to his already determined to be service connected right knee disability, so a secondary consequence. He also suggests that occupational knee strain while serving as an aircraft mechanic in the military caused his left knee disability, therefore that this disability also may have been directly, if not presumptively, incurred during his military service. This claim therefore is predicated on both direct and secondary service connection, and in adjudicating this claim the Board must consider all potential bases of entitlement. See Szemraj v. Principi, 357 F.3d 1370, 1371 (Fed. Cir. 2004). VA has a duty to address all arguments put forth by a claimant and/or theories under which entitlement to benefits sought may be awarded. Robinson v. Peake, 21 Vet. App. 545, 552 (2008) (noting that the Board is required to consider all issues raised either by the claimant or reasonably by the evidence of record), aff'd sub nom. Robinson v. Shinseki, 557 F.3d 1355 (Fed. Cir. 2009); Buckley v. West, 12 Vet. App. 76, 83 (1998) (noting that where the RO and the Board have failed to address an argument reasonably raised by a claimant in support of a claim over which the Court (CAVC) has jurisdiction by virtue of a Notice of Disagreement (NOD) satisfying Veterans Judicial Review Act (VJRA) § 402, the Court will remand the claim with directions that the Board address the particular argument(s) in support thereof). This includes the duty to address arguments a Veteran has specifically made as it relates to the adequacy of any given VA examination. As for what occurred during his service, a review of the Veteran's STRs does not indicate a left knee injury or complaints concerning or treatment for this knee. Moreover, in all of the reports of medical history he completed during his lengthy service, including in anticipation of his separation in April 1969, he denied left knee as well as joint problems more generally. Additionally, the corresponding medical examination reports, including the one completed in connection with his military separation evaluation in April 1969, indicate consistently that his lower extremities were described as normal, so not problematic. It is equally significant that he filed his first post-service disability claim in January 1970, just approximately nine months after separation. And although he claimed entitlement to service connection for a right knee disability and other disabilities, he did not mention any impairment or disability involving his left knee. In fact, the first objective indication of bilateral (left and right) knee disability is in a December 2007 private medical examination report noting severe degenerative joint disease of the knees, so affecting both. In an April 2009 statement, when filing the current petition to reopen his claim, the Veteran asserted that he had bilateral knee pain and stiffness because of cartilage pushing against his knees. He also reported working in aircraft maintenance during his service and consequently having to bend and stoop while working on the aircraft. In his September 2009 NOD, he asserted that his left knee disability was due to an altered gait caused by his right knee disability. He also spoke of a right knee injury in service. On VA examination in January 2013, he reported that he began working on the flight line as a crew chief for several years. His duties involved crawling into and out of small spaces to change cylinders. He recalled that, one day in particular, his left knee gave out and consequently he went to have it treated. Thereafter, the knee symptoms occurred regularly and became increasingly more frequent. He reported undergoing left knee surgery in 2010 or thereabouts. Five months later, in April 2011, he had additional surgery on his right knee. He indicated that he was very sure that it was his left knee that was affected during his service. The examiner determined the Veteran gave a consistent history of long service in a position that required prolonged deep flexion of the knees. He had such pain that he sought medical treatment and continued to have intermittent pain from that time forward. According to the examiner, the history provided by the Veteran was consistent with chronic knee problems. As to the "opposite knee," the examiner opined that it was not likely due to service. The examiner explained that the Veteran did not report problems with the opposite knee during or shortly after service and that his work after service in a tire factory was just as likely the cause of his opposite knee problem. In a March 2013 supplemental opinion, after the Veteran's NOD in which he spoke of the right knee being injured in service was brought to the examiner's attention, the examiner asserted that his previous opinion, in essence, still stood. Namely, he realized that the Veteran's recollection as to the extremity involved in service could have been erroneous. But even if the history recounted by him applied to the right knee rather than the left, the history provided was consistent with a right knee disability that had its onset in service. Thus, the examiner concluded the Veteran's right knee disability was directly related to injuries of this knee that were incurred in service. The examiner further opined, however, that the left knee disability was not due to the right knee disability, as the Veteran did not report left knee trouble until years after service and because the left knee disability was just as likely due to work he did after service. In May 2013, a third clarification was sought. The examiner reiterated the Veteran's current left knee disability was unrelated to his right knee disability because he did not voice complaints regarding the left knee until years after service. Moreover, he had a long history of employment in heavy manufacturing after service. Thus, the long period without complaints regarding the left knee for many years after incurring the right knee disability did not support the likelihood of a causal connection between the left knee disability and the right knee disability. All of the foregoing opinions were authored by the same VA examiner. Analysis Initially, the Board finds that the Veteran's January 2013 assertions regarding sustaining a left knee injury in service were in error due to an apparent memory lapse because of the passage of time and even perhaps age. For a long time, indeed since shortly after his separation from service, he has complained of right knee symptoms since service. The left knee disability, on the other hand, was not first mentioned until decades later. The Board therefore, in this circumstance, may consider the absence of any indication of a relevant medical complaint until so relatively long after service as one factor, just not the only or sole factor, in determining whether a disease or an injury in service resulted in chronic or persistent residual disability. See Maxson v. West, 12 Vet. App. 453, 459 (1999), aff'd sub nom. Maxson v. Gober, 230 F.3d 1330, 1333 (Fed. Cir. 2000). See, too, Mense v. Derwinski, 1 Vet. App. 354 (1991) (holding that VA did not err in denying service connection when the Veteran had failed to provide evidence demonstrating continuity of symptomatology since service and had failed to account for the lengthy time period following the conclusion of his service during which there was no clinical documentation of the claimed disorder). Ultimately, the Board must consider all the evidence relevant to the claim, including the availability of medical records, the nature and course of the disease or disability, the amount of time that has elapsed since military service, and any other pertinent facts. Cf. Dambach v. Gober, 223 F.3d 1376, 1380-81 (Fed. Cir. 2000). Thus, when appropriate, the Board may consider the absence of evidence when engaging in a fact-finding role. See Jordan v. Principi, 17 Vet. App. 261 (2003) (Steinberg, J., writing separately) (noting that the absence of evidence may be considered as one factor in rebutting the aggravation part of the section 1111 presumption of soundness). VA adjudicators have to be careful, however, not to treat the absence of evidence as necessarily equivalent to negative evidence, meaning evidence actually weighing against the claim. See Forshey v. Principi, 284 F.3d 1335, 1358 (Fed. Cir. 2002) (en banc). But still, when the condition at issue - like arthritis - is medically complex rather than simple, there has to be medical nexus evidence supporting the claim, not just mere lay opinion, to establish the required linkage between the condition and the Veteran's military service, including in this instance by way of a service-connected disability. Competent lay evidence means any evidence not requiring that the proponent have specialized education, training, or experience. Lay evidence is competent if it is provided by a person who has knowledge of facts or circumstances and conveys matters that can be observed and described by a lay person. 38 C.F.R. § 3.159(a)(2). Lay evidence may be competent and sufficient to establish a diagnosis of a condition when: (1) a layperson is competent to identify the medical condition (i.e., when the layperson will be competent to identify the condition where the condition is simple, for example a broken leg, and sometimes not, for example, a form of cancer); (2) the layperson is reporting a contemporaneous medical diagnosis, or; (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional. Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007); see also Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009). In ascertaining the competency of lay evidence, the Courts generally have held that a layperson is incapable of opining on matters requiring medical knowledge. In certain instances, however, lay evidence has been found competent with regards to a disease with "unique and readily identifiable features" that is "capable of lay observation." See, e.g., Barr v. Nicholson, 21 Vet. App. 303 (2007) (concerning varicose veins); see also Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (dislocated shoulder); Charles v. Principi, 16 Vet. App. 370 (2002) (tinnitus); Falzone v. Brown, 8 Vet. App. 398 (1995) (flatfeet). Conversely, laypersons equally have been found not competent in more complex medical situations. See Woehlaert v. Nicholson, 21 Vet. App. 456 (2007) (concerning rheumatic fever). See also Colantonio v. Shinseki, 606 F.3d 1378, 1382 (Fed. Cir. 2010) (recognizing that in some cases lay testimony "falls short" in proving an issue that requires expert medical knowledge); Waters v. Shinseki, 601 F.3d 1274, 1278 (Fed. Cir. 2010) (concluding that a Veteran's lay belief that his schizophrenia had aggravated his diabetes and hypertension was not of sufficient weight to trigger VA's duty to seek a medical opinion on the issue). When considering whether lay evidence is competent, the Board must determine, on a case-by-case basis, whether the Veteran's particular disability is the type of disability for which lay evidence may be competent. See Kahana v. Shinseki, 24 Vet. App. 428 (2011). Competent medical evidence, as opposed to lay evidence, is evidence provided by a person who is qualified through education, training, or experience to offer medical diagnoses, statements, or opinions. Competent medical evidence may also include statements conveying sound medical principles found in medical treatises. It also includes statements contained in authoritative writings, such as medical and scientific articles and research reports or analyses. 38 C.F.R. § 3.159(a)(1). In adjudicating a claim, the Board is charged with the duty to assess the credibility and weight given to evidence. See, e.g., Madden v. Gober, 125 F.3d 1477, 1481 (Fed. Cir. 1997), cert. denied, 523 U.S. 1046 (1998) (see also Jefferson v. Principi, 271 F.3d 1072, 1076 (Fed. Cir. 2001) (recognizing the Board's inherent fact-finding ability). And, here, the evidence as it stands reflects no complaints regarding the left knee in service. Indeed, the Veteran consistently denied knee trouble in reports of medical history completed in service, and his lower extremities were regularly described as normal. Moreover, when filing his original disability claim only a few months after separation from service, he did not mention any disability referable to his left knee (only, instead, concerning his right knee and other disabilities). These factors along with the fact that the evidence does not reflect a left knee disability until many years, indeed decades, after service tend to imply that a left knee disability was not incurred in service or even in the first post-service year, certainly for arthritis not the required minimum compensable degree of at least 10-percent disabling. 38 C.F.R. § 4.71a, Diagnostic Codes 5003, 5010, 5257, 5260, 5261, etc. As already explained, there is no evidence of a left knee disability until years after service separation. Hence, the evidence reflects that the left knee disability was not incurred in service or within the first year after service separation so as to, in turn, presume it was incurred in service, and that there additionally was not continuity of symptomatology between service separation and the present. Moreover, the notion of continuity symptomatology only applies if the condition now at issue was first noted in service, which did not occur in this instance. Thus, service connection for the Veteran's left knee degenerative joint disease, a chronic disability under 38 C.F.R. § 3.309(a), is not warranted under 38 C.F.R. § 3.303(a) and (b) or under the presumptive provisions of 38 C.F.R. §§ 3.307, 3.309(a). The only remaining means, then, by which direct service connection could be granted is if the evidence shows the Veteran's left knee disability is otherwise related to his service. 38 C.F.R. § 3.303(d). This includes the possibility of it being due to (caused or aggravated by) his service-connected right knee disability. 38 C.F.R. § 3.310(a) and (b). But the evidence even in this alternative regard is equally unfavorable to the claim. The VA examiner's opinions, when read together, so in combination, collectively indicate the Veteran's left knee disability is not due to his military service, including a result of his right knee disability, such as in having to compensate for it in his altered gait and in ways of this sort. Though repeatedly asked, the VA examiner emphasized there was no indication of a left knee injury or disability in service and that the length of time between service separation and the onset of the left knee disability tended to suggest it was due to post-service employment in heavy manufacturing. The Board is aware that the VA examiner stated the Veteran's left knee disability was "just as likely" due to post-service factors, meaning it just as likely is not. But mere use of cautious language does not always express inconclusiveness in a doctor's opinion. Rather, the opinion should be viewed in its full context and not characterized solely by the medical professional's choice of words. See Lee v. Brown, 10 Vet. App. 336, 338 (1997). And, here, when read in context, the examiner suggested far more strongly that the left knee disability was unrelated to service, including by way of the service-connected right knee disability. Madden, supra. This is evident from him repeatedly emphasizing the lack of left knee injury in service, lack of left knee complaints or findings in service, the many years after service with no sign of a left knee disability (especially in comparison to as concerning the right knee), and the Veteran's post-service history of heavy manufacturing that also placed strain on his left knee. Hence, the Board finds that the left knee disability is not otherwise shown to be related to service. 38 C.F.R. § 3.303(d). Regarding secondary service connection, pursuant to the VA medical opinions of record, the evidence does not show that a left knee disability is in any way related to the service-connected right knee disability. 38 C.F.R. § 3.310(a) and (b). As the VA examiner explained, the right knee disability was incurred years before the onset of the left knee disability. Thus, according to the VA examiner, the left knee disability was not likely due to or aggravated by the service-connected right knee disability. The VA examiner's opinion is competent, and a rationale for the opinion was provided. Thus, the Board finds that it is highly probative. Madden, supra. The Board recognizes the Veteran's argument regarding an etiological link between his left knee disability and his service-connected right knee disability. But as already alluded to, although lay persons are competent to provide opinions on some medical issues, see Kahana v. Shinseki, 24 Vet. App. 428, 435 (2011), arthritic conditions such as degenerative joint disease fall outside the realm of common knowledge of the lay person. See Jandreau v. Nicholson, 492 F.3d 1372, 1377 n.4 (Fed. Cir. 2007) (lay persons not competent to diagnose cancer). The Board, therefore, cannot rely on the Veteran's representations regarding the origins of his current left knee disability. There are two opinions regarding whether the left knee disability is related to the service-connected right knee disability. One is competent and probative, the other is not. The competent and probative evidence indicates there is no causal connection between the left knee disability and the service-connected right knee disability. As such, service connection for the left knee disability cannot be granted as secondary to the service-connected right knee disability, and service connection for the left knee disability on a secondary basis is denied. 38 C.F.R. § 3.310. Finally, in making these determinations, the Board has considered the provisions of 38 U.S.C.A. § 5107(b) and 38 C.F.R. § 3.102, but there is not such a state of approximate balance of the positive evidence with the negative evidence to otherwise warrant a favorable decision. ORDER The claim of entitlement to service connection for a left knee disability is denied. ______________________________________________ KEITH W. ALLEN Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs