Citation Nr: 21029778 Decision Date: 05/17/21 Archive Date: 05/17/21 DOCKET NO. 19-19 347 DATE: May 17, 2021 ORDER Entitlement to service connection for a low back disability is denied. Entitlement to service connection for a right hip disability is denied. Entitlement to service connection for right lower extremity radiculopathy is denied. Entitlement to service connection for a bilateral hearing loss disability is denied. Entitlement to service connection for a right knee disability is denied. FINDINGS OF FACT 1. The Veteran's degenerative arthritis of the lumbar spine was not shown as chronic in service and did not manifest to a compensable degree within the applicable presumptive period; continuity of symptomatology is not established; and the disability is not otherwise etiologically related to an in-service injury or disease. 2. The Veteran's right hip arthritis was not shown as chronic in service and did not manifest to a compensable degree within the applicable presumptive period; continuity of symptomatology is not established; and the disability is not otherwise etiologically related to an in-service injury or disease. 3. The weight of the evidence shows that the Veteran's right lower extremity radiculopathy is secondary to his non-service-connected back disability. 4. The probative evidence of record does not demonstrate that the Veteran's hearing loss manifested within one year of separation, or is etiologically related to service, to include on the basis of continuity of symptomology. 5. The preponderance of the evidence is against finding that a right knee disability began during active service or is otherwise related to an in-service injury or disease. CONCLUSIONS OF LAW 1. The criteria for entitlement to service connection for a low back disability have not been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 2. The criteria for entitlement to service connection for a right hip disability have not been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. 3. The criteria for entitlement to service connection for right lower extremity radiculopathy have not been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. 4. The criteria for entitlement to service connection for a bilateral hearing loss disability have not been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309, 3.385. 5. The criteria for entitlement to service connection for a right knee disability have not been met. 38 U.S.C. §§ 1131, 5107; 38 C.F.R. §§ 3.102, 3.303. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from March 1957 to February 1961. The Veteran attended a hearing before the undersigned Veterans Law Judge in December 2019. A transcript of the hearing is of record. This matter was previously remanded by the Board of Veterans' Appeals (Board) in March 2020. In consideration of the appeal, the Board is satisfied there was substantial compliance with the remand directives and will proceed with review. See, Stegall v. West, 11 Vet. App. 268 (1998). Service Connection Service connection may be granted for disability resulting from disease or injury incurred in or aggravated by active service. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. § 3.303. The three-element test for service connection requires evidence of: (1) a current disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship between the current disability and the in-service disease or injury. Shedden v. Principi, 381 F.3d 1163, 1166 -67 (Fed. Cir. 2004). Certain chronic diseases will be presumed related to service, absent an intercurrent cause, if they were shown as chronic in service; or, if they manifested to a compensable degree within a presumptive period following separation from service; or, if they were noted in service (or within an applicable presumptive period) with continuity of symptomatology since service that is attributable to the chronic disease. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.303, 3.307, 3.309. Walker v. Shinseki, 708 F.3d 1331, 1338 (Fed. Cir. 2013). Service connection may be established on a secondary basis for disability which is proximately due to or the result of service-connected disease or injury. 38 C.F.R. § 3.310(a). Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a) proximately caused by or (b) proximately aggravated by a service-connected disability. Allen v. Brown, 7 Vet. App. 439, 448 (1995) (en banc). Where a service-connected disability aggravates a nonservice-connected condition, a veteran may be compensated for the degree of disability (but only that degree) over and above the degree of disability existing prior to the aggravation. Id. Under applicable criteria, VA shall consider all lay and medical evidence of record in a case with respect to benefits under laws administered by VA. In determining whether service connection is warranted for a disability, VA is responsible for determining whether the evidence supports the claim or is in relative equipoise, with the Veteran prevailing in either event, or whether a preponderance of the evidence is against the claim, in which case the claim is denied. Gilbert v. Derwinski, 1 Vet. App. 49 (1990). 1. Entitlement to service connection for a low back disability The Veteran claims entitlement to service connection for a low back disability. The Veteran contends that he developed a low back disability due to a fall he experienced in service. The Veteran had an examination for his claimed low back disability in August 2017. The examiner opined that it was less likely than not that the Veteran's back condition is related to service. The examiner stated that MRI and x-rays of the back are unavailable to confirm a diagnosis of a bulging disc. The Veteran had another examination for his claimed low back disability in April 2019. The examiner opined that the Veteran's low back condition was less likely than not a result of military service. The examiner stated that there was no record of any fracture in the Veteran's service treatment records at the time of his claimed injury in 1961. The examiner further noted that the Veteran does have changes on exam of degenerative arthritis, which is unrelated to his injury in 1961. The examiner further opined that the Veteran's symptoms of pain and changes with range of motion are due to the natural progression of degenerative changes of his lumbar spine due to aging, and not due to an injury in 1961. At his December 2019 Board hearing, the Veteran testified that he has had back pain since separation from service. The Veteran stated that he injured his back from a fall during his active service. Specifically, the Veteran testified that he slipped on a slick ramp and hit "one of the tie downs that stick up... out of the concrete that they tie the plane to" on his lower back. There is evidence in the service treatment records that the Veteran fell in April 1957 and skinned his knee. There was slight subcutaneous edema on the knee, but no mention of any back pain at that time. However, the Veteran is competent to attest to feeling back pain. In accordance with the March 2020 Board remand, the Veteran had another examination for his back condition in January 2021. The examiner opined that it was less likely than not that the Veteran's back condition was incurred in or caused by his active duty service. The examiner acknowledged the Veteran's statement regarding the fall he had in service injuring his back. However, the examiner indicated that there is no available record of treatment for the Veteran's back condition until many years after separation from service. Accordingly, the examiner concluded that it would be speculation to state the Veteran's back condition is due to service. Furthermore, the examiner cited medical literature and stated that 25 percent of people before age 40 show evidence of disc degeneration and 60 percent of people after age 40 show evidence of disc degeneration. The examiner noted that the Veteran is 81 years old and is very likely to have a back condition at this point due to age. Upon review of the record, the Board finds that service connection for a back condition is not warranted. The Board finds the January 2021 examiner's medical opinion to be highly probative because the examiner provided an adequate rationale based on the relevant evidence of record and appropriate medical literature. The examiner noted the Veteran's competent lay statements of record regarding his in-service back injury, and provided an adequate rationale concluding that the Veteran's back condition was likely due to age based on the medical evidence of record and the appropriate medical literature. To the extent that the Veteran believes that his back condition is linked to his active duty service, the Board notes that he is competent to provide testimony concerning factual matters of which he has fight-hand knowledge and experiences through his senses. Barr v. Nicholson, 21 Vet. App. 303 (2007). However, the question regarding the etiology of his back condition is an issue of causation of a medical condition, which requires a medical determination outside the realm of common knowledge of any lay person. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). Therefore, his lay statements alone are not sufficient to establish the required nexus in this case. The Board must then rely on the available and probative medical evidence, which have found no nexus between the Veteran's back condition and his military service. Finally, service connection may also be granted for chronic disabilities, if such are shown to have been manifested to a compensable degree within one year after the Veteran was separated from service, or based on continuity of symptoms when first noted in service. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309. For this purpose, a chronic disease is one listed at 38 C.F.R. § 3.309(a), to include arthritis. See Walker v. Shinseki, 708 F.3d 1331, 1338-39 (Fed. Cir. 2013). The Veteran contends that he has had pain since service. However, there is no evidence that symptoms of the Veteran's degenerative arthritis of the spine were noted in service, to include at his February 1961 separation exam, at which time his spine was evaluated as normal. Nor is there evidence of arthritis having been diagnosed within one year after service, let alone to a compensable degree. See 38 C.F.R. § 3.309. As such, presumptive service connection is not warranted for this chronic disability. In sum, the evidence preponderates against the claim for service connection for a back disability. There is no reasonable doubt to be resolved, and the claim of entitlement to service connection for a back disability must be denied. 38 C.F.R. § 3.303. 2. Entitlement to service connection for a right hip disability The Veteran claims entitlement to service connection for a right hip disability. The Veteran contends that he developed a right hip disability due to a fall he experienced in service. The Veteran testified at his December 2019 Board hearing, that he injured his hip from a fall during his active service. Specifically, the Veteran testified that he slipped on a slick ramp and hit "one of the tie downs that stick up... out of the concrete that they tie the plane to" on his lower back, and that he tried to get up again and slipped and fell and hit his knee and hip on the side of a "line mule". As above, the service treatment records confirms a slip and fall in April 1957; however, the only complaint was referable to the knee. The Veteran had an examination for this right hip condition in January 2021. The examiner opined that it was less likely than not that the Veteran's right hip condition was incurred in or caused by his active duty service. The examiner acknowledged the Veteran's statement regarding injuring his right hip from a fall on the flight line during service. However, the examiner noted that there is no available record of treatment for the Veteran's hip condition until many years after separation from service. Further, the examiner noted that the Veteran is 81 years old, which is a significant risk factor for right hip arthritis. The examiner noted that the medical literature indicates that 90 percent of people have osteoarthritis in weightbearing joints by age 40. Additionally, the examiner stated that although the Veteran had a right hip injury in service, the injury, the available records, and lay statements do not show a chronic condition consistent with the Veteran's current arthritis. Accordingly, the examiner concluded that the Veteran's current right hip condition diagnosis is more likely than not age related. Upon review of the record, the Board finds that service connection for a right hip condition is not warranted. The Board finds the January 2021 examiner's medical opinion to be highly probative because the examiner provided an adequate rationale based on the relevant evidence of record and appropriate medical literature. The examiner noted the Veteran's competent lay statements of record regarding his in-service right hip injury, and provided an adequate rationale concluding that the Veteran's right hip condition was likely due to age based on the medical evidence of record and the appropriate medical literature. To the extent that the Veteran believes that his right hip condition is linked to his active duty service, the Board notes that he is competent to provide testimony concerning factual matters of which he has fight-hand knowledge and experiences through his senses. Barr v. Nicholson, 21 Vet. App. 303 (2007). However, the question regarding the etiology of his right hip condition is an issue of causation of a medical condition, which requires a medical determination outside the realm of common knowledge of any lay person. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). Therefore, his lay statements alone are not sufficient to establish the required nexus in this case. The Board must then rely on the available and probative medical evidence, which have found no nexus between the Veteran's right hip condition and his military service. Finally, service connection may also be granted for chronic disabilities, if such are shown to have been manifested to a compensable degree within one year after the Veteran was separated from service. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309. For this purpose, a chronic disease is one listed at 38 C.F.R. § 3.309(a), to include arthritis. See Walker v. Shinseki, 708 F.3d 1331, 1338-39 (Fed. Cir. 2013). However, there is no evidence that symptoms of the Veteran's right hip arthritis were noted in service, or that arthritis was diagnosed either in service or within one year after service, let alone to a compensable degree. See 38 C.F.R. § 3.309. Without evidence supporting a diagnosis in service or within one year of separation, the claim is not warranted. In sum, the evidence is against the claim for service connection for a right hip disability. There is no reasonable doubt to be resolved, and the claim of entitlement to service connection for a right hip disability must be denied. 38 C.F.R. § 3.303. 3. Entitlement to service connection for right lower extremity radiculopathy The Veteran contends that his current right lower extremity radiculopathy condition warrants entitlement to service connection. Specifically, the Veteran contends that his right lower extremity radiculopathy was caused by a fall in service or was caused or aggravated by his back condition. The Veteran had an examination for his claimed right lower extremity radiculopathy condition in August 2017. The examiner stated that reports of radiculopathy were subjective only, and therefore a diagnosis could not be confirmed. The Veteran had another examination for his claimed right lower extremity radiculopathy condition in June 2019. The examiner stated that the Veteran does not have signs or symptoms of radicular pain. In accordance with the March 2020 Board remand, the Veteran had another examination for his claimed right lower extremity radiculopathy disability in January 2021. The examiner noted that the Veteran had a diagnosis of right lower extremity radiculopathy. The examiner opined that it was less likely than not that the Veteran's right lower extremity radiculopathy was incurred in or caused by his active duty service. The examiner acknowledged the Veteran's statement that his radiculopathy pain was the result of his in-service injury. However, the examiner noted that there is no record of in-service radiculopathy noted in the Veteran's service treatment records and no mention for radiculopathy until 2011. The examiner opined that it is more likely than not that the Veteran's radiculopathy is secondary to his back condition. Additionally, the examiner opined that the Veteran's back condition causes the Veteran's radiculopathy but does not aggravate his radiculopathy. Upon review of the record, the Board finds that service connection for a right lower extremity radiculopathy condition is not warranted. The Board finds the January 2021 examiner's medical opinion to be highly probative because the examiner provided an adequate rationale based on the relevant evidence of record and appropriate medical literature. The examiner noted the Veteran's competent lay statements of record regarding his in-service injury, and provided an adequate rationale concluding that the Veteran's right lower extremity radiculopathy condition was likely due to his non-service-connected back condition. To the extent that the Veteran believes that his right lower extremity radiculopathy condition is linked to his active duty service, the Board notes that he is competent to provide testimony concerning factual matters of which he has fight-hand knowledge and experiences through his senses. Barr v. Nicholson, 21 Vet. App. 303 (2007). However, the question regarding the etiology of his right lower extremity radiculopathy condition is an issue of causation of a medical condition, which requires a medical determination outside the realm of common knowledge of any lay person. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). Therefore, his lay statements alone are not sufficient to establish the required nexus in this case. The Board must then rely on the available and probative medical evidence, which have found no nexus between the Veteran's right lower extremity radiculopathy condition and his military service. Service connection may be established on a secondary basis for disability which is proximately due to or the result of service-connected disease or injury. The medical evidence of record demonstrates that it is more likely than not that the Veteran's right lower extremity radiculopathy was caused by his claimed back condition. However, service connection for a secondary disability may be granted only when the primary disability is service-connected. Here the Veteran's radiculopathy is secondary to his back condition, which is not service-connected. See 38 C.F.R. § 3.310. Therefore, service connection for radiculopathy as secondary to a back condition is not warranted. Accordingly, the preponderance of the evidence is against the claim for service connection for a right lower extremity radiculopathy disability. There is no reasonable doubt to be resolved, and the claim of entitlement to service connection for a right hip disability must be denied. 38 C.F.R. § 3.303. 4. Entitlement to service connection for a bilateral hearing loss disability The Veteran contends service connection is warranted for a bilateral hearing loss disability. For the purposes of applying the laws administered by VA, impaired hearing will be considered to be a disability when the auditory threshold in any of the frequencies 500, 1000, 2000, 3000, 4000 Hertz is 40 decibels or greater; or when the auditory thresholds for at least three of the frequencies 500, 1000, 2000, 3000, or 4000 Hertz are 26 decibels or greater; or when speech recognition scores using the Maryland CNC Test are less than 94 percent. 38 C.F.R. § 3.385. The Court has held that service connection can be granted for a hearing loss where the Veteran can establish a nexus between his current hearing loss and a disability or injury he suffered while he was in military service. Godfrey v. Derwinski, 2 Vet. App. 352, 356 (1992). The Court has also held that VA regulations do not preclude service connection for hearing loss which first met VA's definition of disability after service. Hensley v. Brown, 5 Vet. App. 155, 159 (1993). The Veteran had an examination for his claimed bilateral hearing loss disability in November 2017. Examination revealed puretone thresholds in both ears of CNT (could not test) at 500, 1000, 2000, 3,000, and 4000. The examiner reported that the test results were not valid, explaining that the Veteran had to be prompted to respond during SRT testing and the Veteran's responses to behavioral audiometry testing were unreliable and invalid. The examiner opined that it was less likely than not that the Veteran's claimed hearing loss was the result of in-service noise exposure. The examiner noted that the Veteran's separation examination indicated that the Veteran's hearing was within normal limits at separation. Additionally, the examiner stated that there is insufficient evidence to determine whether permanent noise-induced hearing loss can develop much later in one's lifetime, long after the cessation of noise exposure. The examiner referenced the 2005 Institute of Medicine (IOM) Study and noted that although the definitive studies to address this issue have not been performed, based on the anatomical and physiological data available on the recovery process following noise exposure, it is unlikely that such delayed effects occur. The Veteran had another examination for his claimed bilateral hearing loss disability in January 2018. Examination revealed puretone thresholds in both ears of CNT (could not test) at 500, 1000, 2000, 3,000, and 4000. Speech audiometry revealed speech recognition ability of CNT in both ears. The examiner noted that the test results are not valid for rating purposes because they are inconsistent with organic hearing loss. The examiner opined that it was less likely than not that the Veteran's hearing loss was caused by or a result of an event in military service. The examiner noted that there was only a whisper examination at the time of entrance into the military, which is not an accurate assessment of hearing. The examiner further noted that the Veteran's separation examination revealed hearing within normal limits. Additionally, the examiner stated that according to the American College of Occupational Medicine Noise and Hearing Conservation Committee, "a noise induced hearing loss will not progress once it is stopped." Therefore, the examiner concluded that the Veteran's current reported hearing loss was less likely than not related to military noise exposure. The Veteran provided a private medical opinion in January 2018 regarding his claimed hearing loss disability. The private examination was from a COSTCO Hearing Aid Center. The examiner stated that the Veteran has profound mixed hearing loss, which is most likely caused by events in service. At the December 2019 Board hearing, the Veteran testified that he was exposed to acoustic trauma during service from working on the flight line and that he lacked adequate hearing protection. Additionally, the Veteran testified that he started wearing hearing aids soon after separation from service. In accordance with the March 2020 Board remand the Veteran had another examination for his claimed hearing loss in January 2021. Examination revealed puretone thresholds in both ears of CNT (could not test) at 500, 1000, 2000, 3,000, and 4000. Speech audiometry revealed speech recognition ability of CNT in both ears. The examiner noted that test results were not valid for rating purposes. The examiner acknowledged that the Veteran has a history of bilateral hearing loss. However, the examiner stated that despite reinstructing the Veteran multiple times his responses to puretone and speech stimuli were inconsistent. As a result, testing was discontinued as all results were invalid. The examiner opined that it was less likely than not that the Veteran's claimed bilateral hearing loss disability was caused by or a result of his active service. The examiner stated that the Veteran's history of "hearing loss" is based on a COSTCO examination, which is insufficient. The examiner stated that based on the available data there is no evidence that the COSTCO exam has ever been substantiated with a VA exam. The examiner noted that the Veteran has history of at least two VA examinations where responses to pure tone and speech stimuli were deemed inconsistent/inorganic and testing was discontinued. Additionally, the examiner noted that objective visual findings on the day of the examination were not consistent with the aforementioned COSTCO exam. The examiner noted that there were inconsistencies with the amount of hearing loss displayed on the COSTCO exam, noting that, even if he were wearing hearing aids, it would be nearly impossible for the Veteran communicate with the examiner to the extent he did while the examiner wore a face mask and face shield during their initial face to face interaction. Furthermore, the examiner noted that hearing was within normal limits bilaterally at the time of separation. The examiner stated that since there is no current existing literature that supports the delayed onset of noise induced hearing loss it is less likely than not that the Veteran's current hearing loss was caused by or a result of military noise exposure. In a March 2021 addendum opinion, the examiner noted the Veteran in service treatment for ear problems. However, the examiner noted that despite noted treatment for ear problems in service, the Veteran's hearing was within normal limits at the time of separation. The examiner further stated that since there is no literature that supports the delayed onset of noise induced hearing loss it is less likely than not that the Veteran's current hearing loss was caused by or a result of military noise exposure. The examiner stated that since the Veteran's hearing was within normal limits at separation, any hearing loss caused by or a result military would have been present on the aforementioned separation examination. The Board finds the probative evidence of record is against finding that the Veteran's claimed bilateral hearing loss is related to his in-service noise exposure. The Board finds the January 2021 and March 2021 examiner's opinions to carry significant probative weight. Both opinions were based on the available evidence of record, including a physical examination of the Veteran, and provided a clear and detailed rationale for their conclusions. Additionally, although lay persons are competent to report symptoms or other matters within their personal knowledge, and to provide opinions on some medical matters (see Kahana v. Shinseki, 24 Vet. App. 428, 435 (2011)), here, the specific matters of the etiology of a bilateral hearing loss disability are complex medical matters that fall outside the realm of common knowledge of a lay person. See Clayburn v. West, 12 Vet. App. 488, 496-97 (1997) (holding that a veteran is not competent to relate currently diagnosed joint disease to the continuous post-service back injury). In this regard, such an opinion requires specialized medical knowledge. The Veteran is not shown to have the necessary training and expertise to provide a competent opinion as to the causes of a bilateral hearing loss disability. Furthermore, the Board notes that the Veteran was provided multiple opportunities to participate in VA audiological evaluations already and there is no indication that the inability to obtain reliable test results was the fault of VA. See Wood v. Derwinski, 1 Vet. App. 190 (1991) (While VA has a duty to assist the Veteran in substantiating his claim, that duty is not a one-way street). Thus, the VA examination reports are deemed adequate for rating purposes and remand for an additional examination is not necessary. Finally, service connection may also be granted for chronic disabilities, if such are shown to have been manifested to a compensable degree within one year after the Veteran was separated from service. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309. For this purpose, a chronic disease is one listed at 38 C.F.R. § 3.309(a), to include hearing loss. See Walker v. Shinseki, 708 F.3d 1331, 1338-39 (Fed. Cir. 2013). Here, although the Veteran has testified that he started wearing hearing aids right after he got out of the service, there is no evidence that the Veteran's bilateral hearing loss was diagnosed either in service or within one year after service, let alone to a compensable degree. See 38 C.F.R. § 3.309. Furthermore, because hearing loss disability is defined by regulation as requiring a specific severity of the condition to qualify as a disability for compensation purposes, and there is no objective medical evidence to support the Veteran's claim of hearing loss since separation, the evidence is against the claim. Without evidence supporting a diagnosis in service or within one year of separation, the claim is not warranted on a presumptive basis. Based on the foregoing, the Board finds that service connection for a bilateral hearing loss disability is not warranted. In reaching this decision, the Board has considered the applicability of the benefit of the doubt doctrine. However, the preponderance of the evidence is against the finding that there is a causal relationship between the Veteran's current claimed bilateral hearing loss and his active military service. As such, service connection for a bilateral hearing loss disability is not warranted. 38 U.S.C. § 5107; 38 C.F.R. § 3.102. 5. Entitlement to service connection for a right knee disability The Veteran contends that he is entitled to service connection for a right knee disability. The Veteran had an examination for his claimed right knee disability in August 2017. The examiner opined that it was less likely than not that the Veteran's knee condition was incurred in or caused by his active service. The examiner indicated that the Veteran's file lacks objective medical evidence to confirm diagnosis for right knee pain due to injury during military service. The Veteran had another examination for his right knee condition in April 2019. The examiner opined that it was less likely than not that the Veteran's right knee condition was incurred in or caused by his active service. The examiner stated that the Veteran's separation exam was silent for knee problems. The examiner further noted that the Veteran's service treatment records did not record a knee fracture in 1961. The examiner further opined that the Veteran's current knee condition is a result of the wear and tear of aging resulting in degenerative arthritis and is unlikely to be due to his knee injury in 1961. The Veteran testified at his December 2019 Board hearing, that he injured his knee from a fall during his active service. Specifically, the Veteran testified that he slipped on a slick ramp and hit "one of the tie downs that stick up... out of the concrete that they tie the plane to" on his lower back, and that he tried to get up again and slipped and fell and hit his knee and hip on the side of a "line mule". As noted above, service treatment records include an April 1957 notation that the Veteran fell and skinned his knee. There was slight subcutaneous edema on the knee, but the x-ray was normal. A September 1957 note indicates that there was a cut on the knee, but there was no follow-up for any knee issues after that. His lower extremities were evaluated as normal at his February 1961 separation examination. In accordance with the March 2020 Board remand, the Veteran had an examination for his claimed right knee disability in January 2021. The examiner opined that it was less likely than not that the Veteran's right knee condition was incurred in or caused by his active duty service. The examiner acknowledged the Veteran's testimony from 2019, where he stated that he injured his right knee in service and that his "right knee buckled and he fell". Furthermore, the examiner stated that although the Veteran had a right knee injury in service, the available records and lay statements do not show a chronic condition consistent with the current strain. The examiner further stated that the record shows that the Veteran's right knee condition began in 2016 and the current exam findings are consistent with the strain diagnosed in 2016. Therefore, the examiner concluded that it was less likely than not that the Veteran's knee condition was due to his active service. Upon review of the record, the Board finds that service connection for a right knee condition is not warranted. The Board finds the January 2021 examiner's medical opinion to be highly probative because the examiner provided an adequate rationale based on the relevant evidence of record. The examiner noted the Veteran's competent lay statements of record regarding his in-service knee injury, and provided an adequate rationale concluding that while the Veteran did injury his right knee during service, the medical and lay evidence of record did not show a chronic condition consistent with the Veteran's current right knee diagnosis. To the extent that the Veteran believes that his right knee condition is linked to his active duty service, the Board notes that he is competent to provide testimony concerning factual matters of which he has fight-hand knowledge and experiences through his senses. Barr v. Nicholson, 21 Vet. App. 303 (2007). However, the question regarding the etiology of his knee condition is an issue of causation of a medical condition, which requires a medical determination outside the realm of common knowledge of any lay person. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). Therefore, his lay statements alone are not sufficient to establish the required nexus in this case. The Board must then rely on the available and probative medical evidence, which have found no nexus between the Veteran's right knee condition and his military service. In sum, the evidence preponderates against the claim for service connection for a right knee disability. There is no reasonable doubt to be resolved, and the claim of entitlement to service connection for a right knee disability must be denied. 38 C.F.R. § 3.303. Bethany L. Buck Veterans Law Judge Board of Veterans' Appeals Attorney for the Board David M. Sebstead, Associate 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.