Citation Nr: 22051118 Decision Date: 09/08/22 Archive Date: 09/08/22 DOCKET NO. 16-08 629 DATE: September 8, 2022 ORDER Entitlement to service connection for a low back or lumbar spine disability, to include on a secondary basis, is denied. Entitlement to service connection for a neck or cervical spine disability, to include on a secondary basis, is denied. REMANDED Entitlement to service connection for a headache disability, to include on a secondary basis, is remanded. FINDINGS OF FACT 1. The Veteran's low back or lumbar spine disability is not secondary to his service-connected bilateral knee disabilities and is not otherwise related to an in-service injury or disease. 2. The Veteran's neck or cervical spine disability is not secondary to his service-connected bilateral knee disabilities and is not otherwise related to an in-service injury or disease. CONCLUSIONS OF LAW 1. The criteria for service connection for a low back or lumbar spine disability as due to service or to service-connected bilateral knee disabilities are not met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. 2. The criteria for service connection for a neck or cervical spine disability as due to service or to service-connected bilateral knee disabilities are not met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from October 1976 to November 1979 and from November 1990 to May 1991, with additional periods of service in the United States Marine Corps Reserves. These matters come before the Board of Veteran's Appeals (Board) from a December 2013 rating decision issued by the Department of Veterans Affairs (VA) Regional Office (RO). These matters were most recently before the Board in February 2022 when the claims were remanded for development. The Board finds the February 2022 remand directives have been substantially complied with, and the matters are again before the Board. Stegall v. West, 11 Vet. App. 268, 271 (1998). The Board acknowledges the February 2022 remand directives specified the medical opinions requested were to be obtained from previous examiners. Unfortunately, while the agency of original jurisdiction (AOJ) requested the opinions from the nurse practitioner that had subscribed the examination reports of November 2021, the addendum opinions obtained in compliance with the February 2022 remand instructions were subscribed by a different subscriber. See Exam Request of February 2022 and April 2022. The Exam Request of April 2022 specifically provides that the opinion may be subscribed by another appropriate clinician if the named clinician is unavailable. This suggests the nurse practitioner that subscribed the examination report of November 2021 was unavailable and hence, another qualified clinician subscribed the addendum opinions of 2022. Thus, in view of the above, the Board finds the record documents the AOJ attempted to substantially comply with the February 2022 remand directives, as they specifically requested the addendum opinions from the prior clinician, were unable to obtain the addendum opinions from the prior clinician, and such inability appears to have been due to the clinician's unavailability. Accordingly, considering the above, as well as the opinions obtained which indicate the subscriber reviewed the evidence of record, to include the examination reports of 2021, and absent any indication in the claims file that further attempts to obtain an addendum opinion from the clinician that subscribed the examination reports of 2021 would be successful or otherwise would aid the Veteran in substantiating his claims, the Board finds the prior remand directives were substantially complied with, although the opinions were subscribed by a different clinician. Service Connection Generally, service connection may be established for a disability resulting from disease or injury in or aggravated by active service. 38 U.S.C. § 1131; 38 C.F.R. § 3.303 (a). To establish service connection for a disability, there must be (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). Service connection may be granted for any disease diagnosed after discharge, when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303 (d). Service connection may be established on a secondary basis for a disability that 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 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. El-Amin v. Shinseki, 26 Vet. App. 136, 138 (2013); Allen v. Brown, 7 Vet. App. 439, 448 (1995). The requirement of a current disability is satisfied when a claimant has a disability at the time a claim for VA disability compensation is filed or during the pendency of that claim. McClain v. Nicholson, 21 Vet. App. 319 (2007). In evaluating the evidence in an appeal, it is the responsibility of the Board to weigh the evidence and decide where to give credit and where to withhold same and, in doing so, accept certain medical opinions over others. Schoolman v. West, 12 Vet. App. 307 (1999). In this regard, the Board has been charged with the duty to assess the credibility and weight given to the evidence. Jandreau v. Nicholson, 492 F.3d 1372 (2007). Competent medical evidence is the type of evidence provided by a person who is qualified through education, training, or experience to offer medical diagnoses, statements, or opinions. It may also include statements conveying sound medical principles found in medical treatises and/or statements contained in authoritative writings, such as medical and scientific articles and research reports or analyses. 38 C.F.R. § 3.159 (a)(1). Competent lay evidence is any kind of 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). This may include some medical matters, such as describing symptoms or relating a contemporaneous medical diagnosis. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007). When there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, the Secretary shall give the benefit of the doubt to the claimant. 38 U.S.C. § 5107 (b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49 (1990). 1. Entitlement to service connection for a low back disability, to include on a secondary basis The Veteran seeks service connection for a lumbar spine condition. See VA Form 21-4138 of March 2013. He also submitted a medical evaluation in support of his claims that associated his claimed lumbar condition to his bilateral knee disabilities. See Report of Consultation and Examination of February 2013, associated with the record in March 2013. Evidence of record The Veteran's service treatment records (STRs) and post-service medical records have been associated with the record. The STRs do not note any treatment or diagnoses pertaining to a lumbar spine disability nor do they note complaints associated with the back, to include pain. See generally STRs, to include various examination reports. In March 2013, a Report of Consultation and Examination was associated with the claims file. This report was subscribed by a physician who noted the Veteran reported complaints of lumbar pain since an in-service knee injury. Diagnoses of degenerative joint disease of the spine and ostearthritis of the lumbar spine were noted, and the physician opined the Veteran's lumbar spine disability was more likely than not causally related to the knee injury to include the associated constant and chronic adaptation and biomechanical compensation for altered gait and weight shifting. See Report of Consultation and Examination of February 2013, associated with the record in March 2013. The opinion provided in the report appears to have been provided based solely on the Veteran's reports of medical history and physical examination results, without review of additional medical records, to include the Veteran's STRs, and without the benefit of diagnostic imaging studies. The Board observes the Veteran was afforded diagnostic imaging studies in 2021 which did not reveal findings consistent with a degenerative disease of the spine. See Back Conditions Disability Benefits Questionnaire (Back DBQ) of October 2021, associated with the record in November 2021. In view of the above, and considering the opinion addresses the likely etiology of a diagnosis of a degenerative disease affecting the lumbar spine, which is not supported by other probative evidence of record, to include diagnostic imaging studies of record, the Board is unable to find this medical opinion is adequate or to afford it any probative value for adjudication purposes. See Stefl v. Nicholson, 21 Vet. App. 120, 123 (2007); Reonal v. Brown, 5 Vet. App. 458, 461 (1993). Notwithstanding, the opinion has been considered competent evidence of limited probative value insofar as it suggests a possible association between the Veteran's back symptomatology and his knee conditions due to, or associated with, an altered gait. See Monzingo v. Shinseki, 26 Vet. App. 97, 107 (2012). In October 2021, the Veteran was administered a Back DBQ. The examiner noted a diagnosis of lumbago as well as the Veteran's reports of having experienced intermittent pain during service. Following the examination, the examiner subscribed a medical opinion noting he was unable to confirm a chronic thoracolumbar disorder as the objective examination was normal and the diagnostic imaging studies completed revealed no abnormal pathologies such as degenerative joint/disc disease. As such, the examiner did not provide a medical opinion on the likely etiology of the Veteran's condition. See medical opinion of October 2021, associated with the record in November 2021. In March 2022, a medical opinion regarding conflicting medical evidence clarified the Veteran's reported symptomatology associated with his low back was consistent with a diagnosis of lumbar strain with lumbago. See medical opinion regarding conflicting medical evidence of March 2022. In April 2022, medical opinions for secondary service connection pertaining to the lumbar disability were associated with the claims file. The subscriber of the opinions noted pertinent information from the Veteran's medical records and opined the Veteran's low back disorder was less likely as not related to his service-connected left knee strain or right knee disability. In favor of these negative opinions, the examiner explained that the low back and the conditions affecting the knees were not medically related, as they are conditions affecting separate body parts and that medical literature failed to demonstrate a causal relationship between the two. Further, the examiner addressed the private medical opinion of 2013 which associated the Veteran's low back disability to his knees, due to gait abnormalities. However, the examiner found the available records did not indicate or otherwise suggest the Veteran had a chronic gait abnormality. Moreover, the examiner explained that the kinds of injuries having significant impact on other uninjured joints, limbs, or spine, are those resulting in major muscle or nerve damage causing partial or complete paralysis or shortening of the injured limb resulting in a length discrepancy of more than 5cm- which would result in a clinically altered gait pattern. The examiner found the Veteran's records, to include the VA examinations, did not reveal a gait abnormality of such severity to support an association between the back and knee conditions. The examiner also noted the Veteran's records did not reveal medical evidence to determine a baseline level of severity of the back disability prior to or contemporaneous to any aggravation by the Veteran's service-connected knee disabilities. See medical opinions for secondary service connection and for aggravation of a nonservice connected condition by a service-connected condition of April 2022. The Board finds these medical opinions adequate and of high probative value. In making this finding the Board acknowledges that when addressing secondary service connection, an opinion must address causation and aggravation separately, as they are independent concepts requiring separate findings and rationale. See Atencio v. O'Rourke, 30 Vet. App. 74, 90-91 (2018); see also El-Amin v. Shinseki, 26 Vet. App. 136, 140-41 (2013). Notwithstanding, medical opinions must be read as a whole and in the context of the evidence of record. Acevedo v. Shinseki, 25 Vet. App. 286, 294 (2012). Here, the subscriber of the April 2022 medical opinions for secondary service connection, appears to have provided the same basic rationale in support of the negative medical opinion for causation and for aggravation; as the examiner found the Veteran's bilateral knee disabilities had not resulted in an altered gait of such severity as to cause or aggravate a low back condition, the records did not show he had experienced an altered gait due to his bilateral knee disabilities and found no evidence in the record to support an aggravation, or an increase in the severity of the non-service connected back disability associated to the service-connected knee disabilities. Based on the provided opinion, it would appear the same basic medical principles or bases would apply to the question of causation and to the question of aggravation in the present context, which does not necessarily render a medical opinion inadequate for adjudication purposes. The opinions, when read as a whole, suggest the examiner determined the back disability was less likely as not caused by the Veteran's bilateral knee disabilities because the spine and the knees are distinct/independent entities and because the knee disabilities did not result in an altered gait of such severity per medical literature as to cause or result in a spine disability affecting the lumbar area. Further, the examiner appears to have concluded that the back disability was less likely as not aggravated by the Veteran's bilateral knee disabilities because the records did not show an increase in the severity of the claimed lumbar disability due to the knee disabilities or otherwise that the knee disabilities resulted in an antalgic gait. As the Board is able to understand the examiner's reasoning, and as the opinions appear to be based on the available evidence of record, to include consideration of the Veteran's statements, and the examiner's expertise, the Board finds these opinions are adequate to adjudicate the matter and affords them high probative value. In April 2022, a medical opinion as to direct service connection was also associated with the record. In pertinent part, the examiner opined the Veteran's low back disability was less likely as not related to the Veteran's service because the Veteran's various physical examination reports during service noted no spine abnormalities, defects, or diagnoses; nor did the STRs document any treatment, complaints or manifestation of a low back condition in service. In reaching the above conclusion the examiner noted the Veteran's lay statements had been considered but had not been found sufficient to support a nexus. See medical opinion for direct service connection of April 2022. Absent any competent evidence of record contrary to the examiner's findings, the Board finds this medical opinion adequate and of high probative value. In making this finding, the Board acknowledges that medical opinions based solely on the absence of medical records documenting an in-service injury are inadequate for adjudication purposes. See Dalton v. Nicholson, 21 Vet. App. 23 (2007). Notwithstanding, medical opinions must be read as a whole and in the context of the evidence of record. Acevedo v. Shinseki, 25 Vet. App. 286, 294 (2012). Here, when the April 2022 medical opinion is read in conjunction with request for a medical opinion (exam request) of April 2022, the other opinions of record regarding the Veteran's back disability, as well as the examination report of November 2021, and in light of the available records, the opinion is found to be based on the clinician's expertise, the available evidence, and with consideration of the Veteran's statements rather than it being based solely on the absence of a documented in-service injury. See also Monzingo v. Shinseki, 26 Vet. App. 97, 105-07 (2012). Thus, the Board affords this opinion high probative value. Analysis The Veteran submitted evidence in favor of his claim for service connection of a low back disability that associated a back condition to the Veteran's bilateral knee disabilities. This evidence explicitly raised the matter of entitlement to service connection for his back disability on a secondary basis to his bilateral knee disabilities. As previously noted, service connection on a secondary basis requires a current disability, a service-connected disability and competent medical evidence associating the two. Here, the Veteran has a current back disability, lumbar strain with lumbago and he is already service connected for bilateral knee disabilities. See medical opinion regarding conflicting medical evidence of March 2022. As such, the first and second requirements for service connection on a secondary basis are satisfied. Unfortunately, the claim fails to surpass the third requirement for service connection on a secondary basis, as the more probative evidence of record does not support finding the Veteran's bilateral knee disabilities have caused or aggravated his claimed back disability. Importantly, the opinions of April 2022 concluded the Veteran's back disability was less likely as not caused by or aggravated by the Veteran's service-connected knee disabilities. In favor of such opinion, the examiner noted that the disabilities affect separate and distinct or independent joints and that the Veteran's bilateral knee disabilities have not resulted in an altered gait to cause or aggravate a back disability and that the available evidence did not support an aggravation of the back disability by the service-connected knee disabilities. These opinions are found to have high probative value as they are based on a thorough review of the evidence of record, and provide an explanation based on the available evidence, to include consideration of the Veteran's statements, to support the negative opinions provided. In reaching this conclusion, the Board acknowledges, the Veteran submitted a positive medical opinion in 2013, which associated a degenerative back disability to his knee conditions and an altered gait. Unfortunately, the available evidence of record does not show the Veteran has arthritis or a degenerative disease affecting the spine, as such the 2013 opinion associating that degenerative diagnosis to the Veteran's knee disabilities lacks probative value. Additionally, although the 2013 opinion suggests an association between the Veteran's back disability and his bilateral knee disabilities, based on an altered gait mechanism caused by the knees; its probative value is outweighed by the VA April 2022 medical opinions and the other evidence of record to include post-service medical records, the various VA examinations addressing the back and knee disabilities, and the Veteran's lay statements of record regarding his knees and his back symptomatology, which do not show or suggest the Veteran has experienced an altered gait or limp associated with his bilateral knee disabilities. See Evans v. West, 12 Vet. App. 22, 30 (1998). Importantly, the Board has reviewed the available post-service medical records, and these generally note the Veteran has had a normal gait. See generally VA medical records, to include those for March 2018 and September 2021. Further, the VA examinations regarding the Veteran's knees do not note objective findings to include any limping, gait disturbances, or limb length discrepancies, nor do the Veteran's reported symptoms suggest such. The VA examination for the back, contains similar findings. See for example VA examinations to include those of September 2021 for the knees and October 2021 for the back. Thus, for the reasons explained above, the Board finds the evidence of record weighs heavily against finding the Veteran's low back or lumbar disability is proximately due to or aggravated by his service-connected knee disabilities. As such, considering the VA examiner that subscribed the April 2022 medical opinion found no evidence to establish a baseline level of severity of the back disability prior to or contemporaneous to any aggravation by the service-connected knee disabilities, and absent any competent evidence to suggest otherwise at this time, the Board is unable to find that further development would aid the Veteran in substantiating his claim of service connection for a back disability, secondary to his bilateral knee disabilities, on an aggravation basis. 38 C.F.R. § 3.310 (b). Accordingly, service connection for a low back disability, as secondary to bilateral knee disabilities is not warranted. The Board acknowledges service connection on a secondary basis is warranted for any increase in severity of a nonservice connected disability. Unfortunately, the available and probative evidence of record does not show or suggest the Veteran's back condition has increased in severity due to his service-connected knee disabilities. The Board has also considered that the Veteran is competent to report his symptoms, to include the onset of his symptoms. While the Veteran's statements have been considered, they are found to be outweighed in probative value by the April 2022 medical opinions and the other evidence of record that does not show or support an association between the conditions on a causation or aggravation basis. The Board has also considered whether service connection on a direct basis would be warranted, in view of the Veteran's lay statements suggesting an in-service onset of back pain. See Back DBQ of October 2021. The evidence of record shows that while diagnostic imaging studies have not revealed any spine abnormalities consistent with a degenerative condition, the Veteran has been diagnosed with a lumbar strain with lumbago (back disability). See Back DBQ of October 2021, and opinion of March 2022 regarding conflicting medical evidence. As such, the claim surpasses the first requirement of the Shedden service connection test, a current disability. The Veteran's STRs, to include periodical examination reports, do not document any low back diagnoses, nor any reported symptoms or complaints associated with the back, to include back pain. See generally STRs. Notwithstanding, the Veteran has provided lay assertions regarding low back pain in-service, which he believed could be due to his military duties. See Back DBQ of October 2021. Hence, for purposes of this analysis, and in view of the Veteran's reported symptomatology; the Board resolves reasonable doubt in the Veteran's favor and finds the second requirement of the Shedden test has been surpassed, the in-service incurrence. Now, the remaining question before the Board is whether the medical evidence of record associates the Veteran's current back disability to his in-service incurrence. Unfortunately, the Board is unable to find the evidence of record supports such association, as the most probative opinion of record, the opinion of April 2022, determined the claimed condition was less likely as not related to service and provided an explanation for reaching such conclusion. See medical opinion for direct service connection of April 2022. Thus, the claim fails to surpass the third requirement of the service connection test, the nexus requirement, as no probative evidence of record associates the Veteran's current back disability to his service. In reaching this conclusion, the Board acknowledges the Veteran's statements, regarding having experienced back pain during service due to his military duties as a combat engineer and his involvement with heavy equipment. These statements have been considered by the Board, as the Veteran is competent to report in-service symptomatology. However, while the Veteran can competently report his symptomatology and the circumstances surrounding such, the Board is unable to find the statements, on their own, are sufficient to adjudicate the claim favorably, as they do not constitute competent medical evidence of a nexus. See King v. Shinseki, 700 F.3d 1339, 1345 (Fed. Cir. 2012); Kahana v. Shinseki, 24 Vet. App. 428, 435 (2011); Jandreau v. Nicholson, 492 F.3d 1372, 1377 n.4 (Fed. Cir. 2007). Moreover, these statements were fully considered by the subscriber of the April 2022 medical opinion but were found to be insufficient to support a medical nexus. Thus, in view of the above and absent any competent and probative evidence of record suggesting otherwise, the claim fails to surpass the third prong of the Shedden service connection test, the nexus requirement, as no probative evidence of record has associated the Veteran's current low back disability to his service, to include his military duties as a combat engineer and/or his involvement with heavy equipment. Accordingly, for the reasons explained above and absent any probative and competent evidence of record showing or otherwise suggesting the Veteran's back disability is at least as likely as not associated to his service; the Board finds the probative evidence of record weighs heavily against the claim, and service connection for a back disability on a direct basis is not warranted. In reaching the above conclusion, the Board has considered the benefit of the doubt doctrine. Here as discussed above, the evidence is neither evenly balanced nor approximately as to whether service connection for a low back disability is warranted. Rather, the evidence persuasively weighs against service connection for the claimed condition on a direct and on a secondary basis. The benefit of the doubt doctrine is therefore not for application. Ortiz v. Principi, 274 F.3d 1361, 1364 (Fed. Cir. 2001). Thus, the claim for a low back or lumbar spine disability is denied. 2. Entitlement to service connection for a neck or cervical spine disability, to include on a secondary basis The Veteran also seeks service connection for a neck or cervical spine condition. See VA Form 21-4138 of March 2013. In favor of the claim, he submitted a medical evaluation associating his cervical spine disability to his bilateral knee disabilities. See Report of Consultation and Examination of February 2013, associated with the record in March 2013. Evidence of record The Veteran's service treatment records (STRs) and post-service medical records have been associated with the record. The STRs do not note any treatment or diagnoses pertaining to a cervical disability nor do they note complaints associated with the neck, to include pain. See generally STRs, to include various examination reports. In March 2013, a Report of Consultation and Examination was associated with the claims file. This report was subscribed by a physician who noted the Veteran reported complaints of cervical pain since an in-service knee injury. Diagnoses of degenerative joint disease of the spine and cervical spondylosis were noted, and the physician opined the Veteran's cervical spine disabilities were more likely than not directly and causally related to the knee injury to include the associated constant and chronic adaptation and biomechanical compensation for altered gait and weight shifting. See Report of Consultation and Examination of February 2013, associated with the record in March 2013. The Veteran was administered diagnostic imaging studies in 2021, which did not reveal findings consistent with a degenerative disease affecting the cervical spine. Neck (Cervical Spine) Conditions Disability Benefits Questionnaire (Cervical DBQ) of October 2021, associated with the record in November 2021. As explained previously, as the diagnosis rendered in the report appears to have been based on the Veteran's reports of medical history, without review of additional medical records, to include the Veteran's STRs, and without the benefit of diagnostic imaging studies, and as the other more probative evidence of record does not support such diagnosis, the Board is unable to afford the opinion any probative value. Notwithstanding, the opinion has been considered competent evidence of limited probative value insofar as it suggests a possible association between the Veteran's neck symptomatology and his knee conditions. In October 2021, the Veteran was also administered a Cervical DBQ that noted a diagnosis of cervical strain. At the examination, the Veteran reported having been involved in a vehicle roll over in 1977, during service, and developing neck pain as a result. The Veteran denied going to sick call or having been seen by a medic for the pain. See Cervical DBQ of October 2021. Following the examination, the examiner subscribed a medical opinion explaining that no chronic diagnosis was made for the cervical spine because the Veteran's diagnostic imaging studies had not revealed abnormalities and his symptoms were subjective only. See medical opinion of October 2021, associated with the record in November 2021. In March 2022, a medical opinion regarding conflicting medical evidence corroborated the Veteran's cervical strain diagnosis. See medical opinion regarding conflicting medical evidence of March 2022. In April 2022, medical opinions for secondary service connection pertaining to the cervical spine were associated with the claims file. The subscriber of the opinions noted pertinent information from the Veteran's medical records and opined the Veteran's cervical spine disorder was less likely as not related to his service-connected left knee strain or right knee disability. In favor of these negative opinions, the examiner explained that the cervical spine and the conditions affecting the knees were not medically related, as they are conditions affecting separate body parts and that medical literature failed to demonstrate a causal relationship between the two. Further, the examiner addressed the private medical opinion of 2013 which associated the Veteran's cervical spine disability to his knees, due to gait abnormalities. However, the examiner found the available records did not indicate or otherwise suggest the Veteran had a chronic gait abnormality. Moreover, the examiner explained that the kinds of injuries having significant impact on other uninjured joints, limbs or spine, are those resulting in major muscle or nerve damage causing partial or complete paralysis or shortening of the injured limb resulting in a length discrepancy of more than 5cm- a length discrepancy that would result in a clinically altered gait pattern. The examiner found the Veteran's records, to include the VA examinations, did not reveal a gait abnormality of such severity to support an association between the conditions. The examiner also noted the Veteran's records did not reveal evidence to determine a baseline level of severity of the cervical spine disability prior to or contemporaneous to any aggravation by the Veteran's service-connected bilateral knee disability. See medical opinions for secondary service connection and for aggravation of a nonservice connected condition by a service-connected condition of April 2022. The Board finds these medical opinions adequate and of high probative value. In making this finding the Board acknowledges that when addressing secondary service connection, an opinion must address causation and aggravation separately, as they are independent concepts requiring separate findings and rationale. Atencio v. O'Rourke, 30 Vet. App. 74, 90-91 (2018); see also El-Amin v. Shinseki, 26 Vet. App. 136, 140-41 (2013). Notwithstanding, medical opinions must be read as a whole and in the context of the evidence of record. Acevedo v. Shinseki, 25 Vet. App. 286, 294 (2012). Here, the subscriber of the April 2022 medical opinions for secondary service connection, appears to have provided the same basic rationale in support of the negative medical opinion for causation and for aggravation; as the examiner found the Veteran's bilateral knee disabilities had not resulted in an altered gait of such severity as to cause a cervical spine condition, the records did not show he had experienced an altered gait due to his knee disabilities and found no evidence in the record to support an aggravation, or an increase in the severity of the non-service connected cervical spine disability associated to the service-connected knee disabilities. Based on the provided opinion, it would appear the same basic principles or bases would apply to the question of causation and to the question of aggravation in the present context, which does not necessarily render a medical opinion inadequate for adjudication purposes. The opinions when read as a whole suggest the examiner determined the cervical spine disability was less likely as not caused by the Veteran's bilateral knee disabilities because the spine and the knees are distinct/independent entities and because the knee disabilities did not result in an altered gait of such severity per medical literature as to cause or result in a spine disability affecting the cervical area. Further, the examiner appears to have concluded that the cervical spine disability was less likely as not aggravated by the Veteran's bilateral knee disabilities because the records did not show an increase in the severity of the claimed disability due to the knee disabilities or otherwise that the knee disabilities resulted in an antalgic gait. As the Board is able to understand the examiner's reasoning, and as the opinions appear to be based on the available evidence of record, to include consideration of the Veteran's statements, and the examiner's expertise, the Board finds these opinions are adequate to adjudicate the matters and affords them high probative value. The examiner also opined the Veteran's cervical spine disability was less likely as not related to his service, to include the claimed 1977 incident or his military duties. In favor of the opinion, the subscriber noted the Veteran's STRs did not reveal any pertinent information showing or suggesting the existence of a neck disorder and explained that while the Veteran's assertions had been considered, they were not sufficient to establish a nexus. See medical opinion for direct service connection of April 2022. Absent any competent evidence of record contrary to the examiner's findings, the Board finds this medical opinion adequate and of high probative value. In making this finding, the Board acknowledges that medical opinions based solely on the absence of medical records documenting an in-service injury are inadequate for adjudication purposes. See Dalton v. Nicholson, 21 Vet. App. 23 (2007). Notwithstanding, medical opinions must be read as a whole and in the context of the evidence of record. Acevedo v. Shinseki, 25 Vet. App. 286, 294 (2012). Here, when the April 2022 medical opinion is read in conjunction with the other opinions of record regarding the Veteran's cervical spine disability, as well as the examination report of November 2021, and in light of the available records, the opinion is found to be based on the clinician's expertise, the available evidence, and with consideration of the Veteran's statements rather than it being based solely on the absence of a documented in-service injury. See also Monzingo v. Shinseki, 26 Vet. App. 97, 105-07 (2012). Thus, the Board affords this opinion high probative value. Analysis The Veteran submitted evidence in favor of his claim of service connection for a cervical spine disability that associated the condition to the Veteran's bilateral knee disabilities. This evidence explicitly raised the matter of entitlement to service connection for cervical disability on a secondary basis. As previously noted, service connection on a secondary basis requires a current disability, a service-connected disability, and competent medical evidence associating the two. Here, the Veteran has a current cervical spine disability, and he is already service connected for bilateral knee disabilities. As such, the first and second requirements for service connection on a secondary basis are satisfied. Unfortunately, the claim fails to surpass the third requirement for service connection on a secondary basis, as the more probative evidence of record, the medical opinions of April 2022, do not support finding the Veteran's bilateral knee disabilities have caused or aggravated his claimed cervical spine disability. In favor of such opinion, the examiner noted that the disabilities affect separate and distinct or independent joints and that the Veteran's bilateral knee disabilities have not resulted in an altered gait to cause or aggravate a cervical spine disability and in view of the available records which did not show an aggravation of the cervical spine disability by the service-connected knee disabilities. In reaching this conclusion, the Board acknowledges, the Veteran submitted a positive medical opinion in 2013, which associated a cervical spine disability to his knee conditions and an altered gait. Unfortunately, the available evidence of record does not show the Veteran has arthritis or a degenerative disease affecting the cervical spine, as such, the 2013 opinion associating that degenerative diagnosis to the Veteran's knee disabilities lacks probative value. Further, the opinion is of limited probative value as to its association between the Veteran's back disability and his bilateral knee disabilities, as such association is predicated upon an altered gait mechanism caused by the knees. Unfortunately, the available evidence of record, to include post-service medical records, the various VA examinations addressing the back and knee disabilities, and the Veteran's lay statements of record regarding his knees and his back symptomatology, does not show or suggest the Veteran's bilateral knee disabilities have resulted in an altered gait of any extent, to include one of such severity as to cause antalgic gait or a shortening of the limbs. As such, the Board affords more probative weight to the April 2022 medical opinions which are based on a review of the available evidence, consider the Veteran's history and statements and provide a reasoned explanation to support the conclusion reached. Hence, as the more probative evidence of record, the opinions of April 2022, do not support finding the Veteran's bilateral knee disabilities have caused or aggravated the Veteran's cervical spine condition, the claim fails to surpass the third element for service connection on a secondary service and must be denied. In reaching this conclusion, the Board has considered that service connection on a secondary basis is warranted for any increase in severity of a nonservice connected disability. Unfortunately, the available evidence of record does not show or suggest the Veteran's cervical condition has increased in severity due to his service-connected knee disabilities. Further, the VA examiner that subscribed the April 2022 medical opinion found no evidence to establish a baseline level of severity of the cervical disability prior to or contemporaneous to any aggravation by the service-connected knee disabilities. As such, and absent any competent evidence to suggest otherwise at this time, the Board is unable to find that further development would aid the Veteran in substantiating his claim of service connection for a cervical disability, secondary to his bilateral knee disabilities. 38 C.F.R. § 3.310 (b). The Board has also considered whether service connection on a direct basis is warranted, in view of the Veteran's assertions regarding neck pain following a vehicle roll-over in 1977. See Cervical DBQ of October 2021. Here, the evidence of record shows the Veteran has a diagnosis of cervical strain, and as such the first prong of the Shedden service connection test, is surpassed. The Veteran's STRs do not show or suggest he complained of neck pain, received treatment or was diagnosed with a condition affecting the neck or cervical spine during service. See generally STRs. Notwithstanding, the Veteran has reported having experienced neck pain following a vehicle roll-over in 1977. Thus, for purposes of this analysis and in consideration of the Veteran's assertion, the Board resolves reasonable doubt in the Veteran's favor and finds the claim surpasses the second prong of the Shedden test, the in-service incurrence. Unfortunately, the claim fails to surpass the third prong of the Shedden service connection test, the nexus requirement as no probative medical evidence has associated his Veteran's cervical spine disability to his service, to include the claimed incident in 1977 resulting in neck pain. Importantly, the only medical opinion of record addressing this matter determined the Veteran's cervical spine disability was less likely as not related to his service, to include the claimed 1977 incident or his military duties. In favor of the opinion, the subscriber noted the Veteran's STRs did not reveal any pertinent information showing or suggesting the existence of a neck disorder and explained that while the Veteran's assertions had been considered, they were not sufficient to establish a nexus. See medical opinion for direct service connection of April 2022. Thus, in view of the above and absent any competent and probative evidence of record suggesting otherwise, the claim fails to surpass the third prong of the Shedden service connection test, the nexus requirement, as no probative evidence of record has associated the Veteran's current cervical spine disability to his service, to include his military duties or the claimed incident in 1977. Accordingly, for the reasons explained above and absent any probative and competent evidence of record showing or otherwise suggesting the Veteran's cervical spine disability is at least as likely as not associated to his service; the Board finds the probative evidence of record weighs heavily against the claim, and service connection for a cervical spine disability on a direct basis is not warranted. In reaching the above conclusion, the Board has considered the benefit of the doubt doctrine. Here, as discussed above, the evidence is neither evenly balanced nor approximately so as to whether service connection for a neck or cervical spine disability is warranted. Rather, the evidence persuasively weighs against service connection for the claimed condition on a direct and on a secondary basis. The benefit of the doubt doctrine is therefore not for application. Ortiz v. Principi, 274 F.3d 1361, 1364 (Fed. Cir. 2001). Thus, the claim for a neck or cervical spine disability is denied. REASONS FOR REMAND 1. Entitlement to service connection for a headache disability, to include on a secondary basis. In February 2022, the Board remanded this matter for clarification as to the Veteran's headache condition, to include whether it was a diagnosable disorder, and for medical opinions addressing whether the condition was secondary to any of the Veteran's service-connected disabilities. See February 2022 Board remand directives. Pursuant to the remand directives, various medical opinions addressing whether the Veteran's headaches were secondary to his service-connected disabilities were obtained. See medical opinions of March 2022 and April 2022. Unfortunately, the opinions obtained are conclusory in nature and do not address the matter of aggravation. Importantly, opinions addressing secondary service connection must address causation and aggravation separately, as they are independent concepts requiring separate findings and rationale. Atencio v. O'Rourke, 30 Vet. App. 74, 90-91 (2018); see also El-Amin v. Shinseki, 26 Vet. App. 136, 140-41 (2013). As such, these opinions do not provide sufficient information for the Board to make an informed decision on the matter. Thus, for reasons explained above, the opinions obtained are insufficient for adjudication purposes and the matter of service connection for headaches must be remanded for further development. The matter is REMANDED for the following actions: 1. Obtain any outstanding VA medical record. 2. Obtain medical opinions addressing whether the Veteran's headache condition, it at least as likely as not proximately due to or aggravated by any of his service-connected disabilities. In rendering his or her opinion, the examiner should address both the causation and aggravation prongs in his or her rationale separately. In other words, even if the Veteran's service-connected disabilities did not cause his headache condition, the examiner should still address whether his service-connected disabilities have aggravated, or increased in severity, his headache condition. A clear rationale for all opinions must be provided, and a discussion of the facts and medical principles involved would be of considerable assistance to the Board. 3. After completing the above requested actions, and any additional notification and/or development deemed warranted, readjudicate the issue on appeal. If the benefit sought on appeal remains denied, furnish to the Veteran and his representative an appropriate supplemental statement of the case that includes clear reasons and bases for all determinations, and afford them the appropriate time period for response before the claims file is returned to the Board for further appellate consideration. KRISTI L. GUNN Veterans Law Judge Board of Veterans' Appeals Attorney for the Board Gonzalez-Maldonado, Belmari 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.