Citation Nr: 21071806 Decision Date: 12/01/21 Archive Date: 12/01/21 DOCKET NO. 15-45 428 DATE: December 1, 2021 ORDER Entitlement to service connection for a left knee disability is granted. FINDING OF FACT The competent and probative evidence is at least in equipoise as to whether the Veteran's left knee disability is secondary to his service-connected right knee disability. CONCLUSION OF LAW Resolving reasonable doubt in the Veteran's favor, service connection for a left knee disability is warranted. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. REASONS AND BASES FOR FINDING AND CONCLUSION The Veteran served on active duty from September 1963 to September 1967. This matter is before the Board of Veterans' Appeals (Board) on remand from the U.S. Court of Appeals for Veterans Claims (CAVC). The Veteran died in December 2020, during the pendency of this appeal. His widow (the appellant) has been recognized by VA as his substitute claimant. The matter was initially before the Board on appeal of an April 2015 rating decision. In January 2018, the case was remanded for further development. A November 2019 Board decision denied service connection for a left knee disability. The Veteran appealed that decision to the CAVC. A December 2020 CAVC Order vacated the Board's November 2019 decision that denied service connection for a left knee disability and remanded it to the Board for further development and re-adjudication consistent with terms of a December 2020 Joint Motion for Remand (JMR). [The Board notes that a May 2021 CAVC Order granted, in part, the appellant's motion for substitution Nunc Pro Tunc to December 4, 2020, the date of the Veteran's death.] In the December 2020 JMR, the parties agreed that the Board erred because it did not adequately explain why it did not assign "significant probative weight" to the private medical opinions of record. The Board had found that the private medical opinions, dated December 2008 and May 2015, had less probative value because there was no indication that the providers had reviewed the Veteran's claims file (were familiar with the entire record). The JMR directed that remand for the Board to adequately address the probative value of the private providers' opinions was required. Additionally, the parties agreed that the Board failed to adequately address certain issues concerning the VA examinations of record while relying on them to deny the claim. On August 2018 VA examination, the examiner opined that it was less likely than not that the Veteran's right knee disability caused or aggravated a left knee disability. She explained, in part, that while the Veteran's left knee degenerative joint disease (DJD) was "within the realm of possibility," it was not likely to be "mostly" caused by his service-connected right knee disability (which is too high a standard for an assessment of secondary service connection). Also, on October 2015 and August 2018 VA examinations, the examiners attributed the Veteran's left knee disability to normal age-related and weight-related degeneration; however, neither examiner opined on the possibility that the Veteran's obesity was due to limitations imposed by his service-connected right knee, and in turn led to compensation by the left knee. Such theory of entitlement was raised by the Veteran's representative in a September 2016 statement. Entitlement to service connection for a left knee disability is granted. Service connection will be granted for a disability resulting from disease or injury incurred in or aggravated by active service. 38 U.S.C. §§ 1110, 1131. Establishing service connection generally requires (1) medical evidence of a current disability; (2) medical or, in certain circumstances, lay evidence of in-service incurrence or aggravation of a disease or injury; and (3) evidence of a nexus between the claimed in-service disease or injury and the present disability. Shedden v. Principi, 381 F.3d 1163 (Fed. Cir. 2004). Service connection may be established on a secondary basis for a disability which is proximately due to or the result of a service-connected disease or injury. 38 C.F.R. § 3.310(a). Additional disability resulting from the aggravation of a non-service-connected condition by a service-connected condition is also compensable under 38 C.F.R. § 3.310(b). The appellant asserts that the Veteran's left knee disability was caused or aggravated by his right knee disability or, in the alternative, that his obesity was caused by limitations imposed by his right knee disability, which in turn led to compensation for the limitation and worsening of his left knee disability. The Veteran's service treatment records (STR) are silent for any complaints or treatment of a left knee disability. A March 2008 left knee MRI showed osteoarthritic changes at the anterior compartment and fluid in suprapatellar bursa. A March 2008 VA treatment record notes that the Veteran reported bilateral knee pain for the last several years. He related that prolonged walking, standing, and squatting, aggravated his knees. On examination, it was noted that he could ambulate without an assistive device, but had an antalgic gait. On September 2008 VA examination, left knee osteoarthritis was diagnosed. The examiner opined that based on his medical history, chronology, and clinical and imaging information, it was less likely than not that the Veteran's left knee disability was related to his service or caused or aggravated by his service-connected right knee disability. In a December 2008 private medical statement (by a provider who had treated the Veteran since at least January 2008) the provider indicated that the Veteran was being evaluated for arthritis of both knees and the lumbar spine. Increasing arthritic changes were noted in the right knee, and degenerative changes and arthritis were identified in the left knee, and confirmed with X-rays. The provider opined that the increased arthritic changes in the Veteran's right knee had increased stress across his back due to his altered gait and increased the use of his left knee, which made him more prone to develop arthritis in those areas. A May 2015 private treatment record notes that the Veteran recently underwent a left total knee replacement (TKR). He reported left knee soreness and weakness, that his gait was off balance, and that he walked with a lean in his gait. The provider indicated that he discussed with the Veteran that there was a causal relationship between the arthritis that developed in his left knee and his right knee arthritis and right TKR because he favored his left knee for an extended period. In an October 2015 VA left knee etiology opinion, the provider stated that it was less likely than not that the Veteran's left knee disability was caused or aggravated by his right knee disability. She explained that the Veteran's left knee disability was due to the normal expected age-related knee joint changes in a 69-year-old morbidly obese male. On August 2018 VA left knee examination, the examiner opined that it was less likely than not that the Veteran's left knee disability was caused or aggravated by his right knee disability, and that it was more likely than not related to age. She also noted that the Veteran was overweight, knee osteoarthritis was a disorder that was associated with age and weight, and the prevalence of osteoarthritis was about 50 percent in people 65 and older. The examiner acknowledged that the Veteran had a right knee injury. However, according to a paper entitled "Symptoms in the Opposite or Uninjured Leg" by the Workplace Safety and Insurance Appeals Tribunal (August 2005), there is no clear evidence to suggest that an injury to one lower extremity would have any significant impact on the opposite uninjured limb unless the injury resulted in major muscle or nerve damage causing partial or complete paralysis of the damaged leg. The examiner further opined that while the Veterans left knee DJD was "within the realm of possibility," it was not likely to be "mostly" caused by the service-connected right knee disability. In a June 2021 VA left knee etiology opinion, the provider opined that it was less likely than not that the Veteran's left knee disability was related to his service because STRs did not document complaints or treatment for a left knee disability during service. However, the provider also opined that it was at least as likely as not that the Veteran's left knee disability was caused or aggravated by his right knee disability. She indicated that she reviewed the file, to include the previous VA and private opinions and examinations, noting a right knee injury was service-connected, and in 2008, he was found to have left knee arthritis associated with pain. The provider explained that gait abnormalities are typically associated with a physical disease, condition, or deformity, and that arthritis is among the disorders that can cause an abnormal gait. She further indicated that joint pain, limited range of motion of a joint, or joint deformity associated with arthritis, may also be factors associated with an abnormal gait. There is VA and private opinion evidence for and against the instant claim. The September 2008 and October 2015 VA opinions (against the claim) are inadequate because they lack adequate rationale, and the August 2018 VA opinion (also against his claim) is inadequate because although a likely alternate nonservice-related etiology (age) was identified, and the provider explained that while the Veteran's left knee DJD was "within the realm of possibility," it was not likely to be "mostly" caused by his service-connected right knee disability (which the JMR parties noted was an incorrect standard of review). Further, the August 2018 examiner did not opine on the possibility that the Veteran's obesity was due to limitations imposed by his (service-connected) right knee, which in turn led to a compensatory burden on the left knee. The December 2008 and May 2015 private medical opinions and June 2021 VA opinion are probative evidence in support of the Veteran's claim and the Board finds them (cumulatively) persuasive. The December 2008 provider had treated the Veteran since (at least) January 2008, was familiar with his ongoing treatment for a left knee disability (the history of the disability), and indicated that increased arthritic changes in the Veteran's right knee had increased stress across his back due to his altered gait and increased use of the left knee, which made him more prone to develop arthritis in those areas. The May 2015 provider also opined that the left knee arthritis developed because he favored his left knee for an extended period due to his right knee disability (and its treatment). Additionally, the June 2021 VA provider indicated that she reviewed the evidence of record and opined that the Veteran's left knee disability was related [secondary] the right knee disability because gait abnormalities are typically associated with a physical disease, condition, or deformity, and that arthritis is among the disorders that can cause an abnormal gait (suggesting that a right knee disability caused a gait abnormality, which, in turn, caused a left knee disability). The Board notes that the providers expressed familiarity with the Veteran's medical history and cited to factual data and relevant medical evidence, and has no reason to question the providers' competence in this matter. Notably, the providers who commented on the matter agreed that an abnormal gait, due to the right knee disability, caused or aggravated the Veteran's left knee disability. The Board finds the opinions to be competent, probative, and (cumulatively) ultimately persuasive evidence regarding the etiology of the Veteran's left knee disability. Giving the Veteran the benefit of the doubt, and absent more probative evidence to the contrary, the Board finds that the evidence of record supports that the Veteran's left knee disability was at least as likely as not caused by his service-connected right knee disability. Therefore, secondary service connection for a left knee disability is warranted. GEORGE R. SENYK Veterans Law Judge Board of Veterans' Appeals Attorney for the Board J. Bayles, Counsel The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.