Citation Nr: 21073542 Decision Date: 12/09/21 Archive Date: 12/09/21 DOCKET NO. 15-14 735A DATE: December 9, 2021 ORDER Service connection for degenerative disc disease of the lumbar spine is denied. Service connection for pes planus is granted. Service connection for right wrist disability is denied. Service connection for bilateral carpal tunnel syndrome is denied. Service connection for sleep apnea is denied. FINDINGS OF FACT 1. The Veteran's degenerative disc disease of the lumbar spine was not shown in service, was not manifested within a year from service or for many years thereafter, and is not etiologically related to service or service-connected disability. 2. Resolving reasonable doubt in the Veteran's favor, the Veteran's pes planus is related to his active service. 3. The Veteran's right wrist disability and bilateral carpal tunnel syndrome was not shown in service, was not manifested within a year from service or for many years thereafter, and is not etiologically related to service or service-connected disability. 4. The Veteran's sleep apnea was not shown in service or for many years thereafter, and is not etiologically related to service or service-connected disability. CONCLUSIONS OF LAW 1. The criteria for service connection for degenerative disc disease of the lumbar spine have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.303, 3.304, 3.307, 3.309, 3.310. 2. The criteria for service connection for pes planus have been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.303, 3.304, 3.307, 3.309. 3. The criteria for service connection for right wrist disability have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.303, 3.310. 4. The criteria for service connection for bilateral carpal tunnel syndrome have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.303, 3.310. 5. The criteria for service connection for sleep apnea have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.303, 3.310. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty in the United States Army from June 1978 to June 1982, with additional service in the National Guard and Army Reserves until August 1998. This matter comes before the Board of Veterans' Appeals (Board) on appeal from March 2013 and July 2014 rating decisions issued by the Agency of Original Jurisdiction (AOJ). By rating action of March 2013, service connection for low back disability, wrist disability, bilateral hand disability, and flat feet were denied; rating action of July 2014 denied service connection for sleep apnea. As a preliminary matter, the Board notes that the Veteran presented testimony during two hearings before two different Veterans Law Judges (VLJs) who conducted Central Office hearings in Washington, D.C. The first hearing was held in August 2018 and the second hearing in March 2021, transcripts of both hearings are associated with the record. In June 2021, the Veteran was notified of his right to an additional hearing before a third VLJ, which he waived. Arneson v. Shinseki, 24 Vet. App. 379, 386 (2011). Thus, the Board will proceed to review the issues addressed herein by the undersigned panel of three judges. Finally, this matter was previously before the Board in March 2019 where the issue of service connection for degenerative disc disease of the lumbar spine was reopened and remanded for additional development. The matter was recently remanded in July 2020 for further development. Legal Criteria Service connection will be granted if the evidence demonstrates that a current disability resulted from an injury or disease incurred in or aggravated by active service. 38 U.S.C. §§ 1110, 1131; 38 C.F.R. § 3.303(a). Establishing service connection generally requires competent evidence of three things: (1) a current disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship, i.e., a nexus, between the claimed in-service disease or injury and the current disability. Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004). Service connection may also be established on a secondary basis for a disability that is proximately due to or the result of a service-connected disease or injury. 38 C.F.R. § 3.310(a). Establishing service connection on a secondary basis requires evidence showing that (1) a current disability exists and (2) the current disability was either (a) caused by or (b) proximately aggravated by a service-connected disability. Allen v. Brown, 7 Vet. App. 439, 448-49 (1995). Service connection may not be awarded on the basis of aggravation without establishing a pre-aggravation baseline level of disability and comparing it to the current level of disability. 38 C.F.R. § 3.310(b). Service connection may also be established under 38 C.F.R. § 3.303 (b), where a condition in service is noted but is not, in fact, chronic, or where a diagnosis of chronicity may be legitimately questioned. The continuity of symptomatology provision of 38 C.F.R. § 3.303 (b) has been interpreted as an alternative to service connection only for the specific chronic diseases listed in 38 C.F.R. § 3.309 (a). Walker v. Shinseki, 718 F.3d 1331 (Fed. Cir. 2013). Service connection may also be established with certain chronic diseases based upon a legal presumption by showing that the disorder manifested itself to a degree of 10 percent disabling or more within one year from the date of separation from service. Such disease shall be presumed to have been incurred in service, even though there is no evidence of such disease during the period of service. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309(a). While the disease need not be diagnosed within the presumption period, it must be shown, by acceptable lay or medical evidence, that there were characteristic manifestations of the disease to the required degree during that time. The Board notes that the service treatment records in this case are limited to those from Reserve service and do not include active service STRs. VA has made reasonable efforts to obtain the missing active service records. In these circumstances, the duty to assist does not require additional action on the part of VA. However, when a veteran's STRs are unavailable through no fault of his own, VA's duty to provide reasons and bases for its findings and conclusions, and to consider carefully the benefit-of-the-doubt rule are heightened. O'Hare v. Derwinski, 1 Vet. App. 365, 367 (1991). The Board has undertaken its review with this in mind. 1. Entitlement to service connection for degenerative disc disease of the lumbar spine. For the reasons explained below, the Board finds service connection for degenerative disc disease of the lumbar spine is not warranted. The Veteran contends that his current lumbar spine disability is related to his period of service, to include as a result of a motor vehicle accident (MVA) in 1980. Alternatively, the Veteran contends that his lumbar spine disorder is secondary to his service-connected bilateral knee disability. See March 2021 Hearing Transcript at 13. Initially, the Board notes the Veteran's report of being in an MVA and having back pain following the accident was deemed credible in the Board's prior decisions issued in March 2019 and July 2020. Such positive findings will not be disturbed. By way of history, the Veteran's original claim for degenerative disc disease of the lumbar spine was denied in an unappealed October 2008 rating decision. He filed a claim to reopen in August 2011, and although considered reopened, service connection was again denied in a rating decision of March 2013. As indicated earlier, the Board also reopened the matter in March 2019. The Veteran's service treatment records from his period of active duty are unavailable for review. See Formal Finding dated March 2013. However, the AOJ obtained available Reserve service treatment records for periods 1984 to 1992 and for 1996 to 1997. The available records are negative for any complaint, treatment, or diagnosis of a back disability. Likewise, post-service records are absent for any findings or ongoing treatment for a back disability in the years proximate to service. The earliest record of "low back pain" was in the Veteran's VA treatment record of October 2003. The record includes a December 2016 VA back examination where a VA physician rendered an opinion addressing secondary service connection. After personal examination of the Veteran, the VA physician opined that the Veteran's lumbar spine condition was less likely than not proximately due to or the result of service-connected bilateral knee disability. In support of this conclusion, the VA physician recorded the Veteran's report of having had "chronic back pain for the past few years." The physician added the Veteran had a normal gait and there was no evidence that the Veteran's "service-connected bilateral knee conditions have caused shifting of weight bearing, causing abnormal stress or strain of his lumbar spine." The physician noted review of x-rays taken in July 2015 which showed degenerative disc disease (DDD) of the lumbar spine and added "DDD of the lumbar spine is the result of degenerative of lumbar discs from movement of the lumbar spine as part of aging process." See Medical Opinion DBQ dated December 2016. Additionally, the December 2016 VA physician provided an opinion addressing aggravation. Specifically, the physician opined that the Veteran's lumbar spine was less likely than not aggravated beyond its natural progression by his service-connected bilateral knee disability. As the baseline, the physician noted the earliest medical evidence of mild to moderate degenerative disc disease of the lumbar spine from an x-ray taken in September 2010. Another x-ray of the lumbar spine of July 2015 "showed slightly worse degenerative disc disease of the lumbar spine over a period of 5 years indicates a natural progression of the lumbar spine condition as part of aging process. Thus, there is no evidence that his degenerative disc disease of the lumbar spine was aggravated by any condition, to include his service-connected [bilateral knee disability]." Id. In compliance with the Board's recent July 2020 remand, the Veteran was afforded another VA contract examination in August 2020, with a medical opinion obtained in September 2020. For direct service connection, the examiner found it was less likely than not that the Veteran's current claimed back disability was caused by an MVA in service or any other in-service event. The examiner indicated there was "no record of an MVA in 1980 but even if he had a documented MVA in 1980, the veteran never complained of any injury or any residual injury due to an MVA. If a person has an accident resulting in an injury which becomes a chronic problem leading to any level of disability, this would be expected to manifest at least within the 16 years from the time of the accident until 1996 when the veteran stated in his own words that he was in good health and indicated no medical problems on the Report of Medical History dated [September 1996]." See VA contract medical opinion dated September 2020. The Board acknowledges the favorable medical opinions submitted by the Veteran. After his March 2021 hearing, the Veteran submitted a statement from his treating physician, J.S.W., M.D., who rendered a statement in support of the Veteran's claim. The treating physician indicated that it was "plausible that the back pain from degenerative disc disease could have stemmed from the MVA" that occurred while the Veteran was enlisted in 1980. However, the treating physician indicated he "only met [the veteran] in 2018" and "have had four clinic encounters" and therefore "cannot comment on his conditions or evaluations prior to that point or comment on the state of his health during his four years in the service starting in 1978." Lastly, the treating physician acknowledged he only reviewed a copy of the Statement of the Case (SSOC) dated September 2020. See Statement from J.S.W., M.D. of UNC Health Care dated March 2021. The Veteran submitted another favorable statement dated April 2021 rendered by a VA physician who opined that the Veteran's lumbar spondylosis is at least as likely as not related to his military service. The VA physician noted review of the Veteran's electronic medical record and treatment notes from non-VA providers, and acknowledged that the Veteran served in the artillery division of the United States Army from 1978 until 1982 and in the Army Reserves from 1982 until 1997. See Statement from VA physician dated April 2021. Upon review of the evidence of record, the Board finds that the preponderance of the evidence is against the Veteran's claim of service connection for degenerative disc disease of the lumbar spine. In so finding, the Board assigns significant probative value to the December 2016 and September 2020 VA medical opinions. The VA medical opinions are based on thorough and comprehensive review of the Veteran's claims file, consideration of lay evidence of record, and provide well-grounded rationale to support the examiners' conclusions. Both examiners in particular provide substantial reasoning and explanation as to why the Veteran's current degenerative disc disease of the lumbar spine is not etiologically related to service or service-connected bilateral knee disability. The opinions are sufficient to satisfy the statutory requirements of producing an adequate statement of reasons and bases where the expert has fairly considered material evidence which appears to support the Veteran's position. Wray v. Brown, 7 Vet. App. 488, at 492-93 (1995). Accordingly, the Board finds great probative value to the collective December 2016 and September 2020 VA medical opinions. In contrast, the Board finds the March 2021 statement from J.S.W., M.D, the Veteran's treating physician, carries less probative value as it is speculative and inconclusive in nature. The physician prefaced his opinion by using the term "could" and stating, "I think it is plausible", which is too speculative to establish a medical nexus. Bloom v. West, 12 Vet. App. 185 (1999) (holding that a medical opinion based on speculation, without supporting clinical data or other rationale, does not provide the required degree of medical certainty). Moreover, by the physician's own admission, his opinion is based on "four clinic encounters" and limited to only review of a September 2020 SSOC for background and not the entire electronic claims file. Thus, this is afforded less probative weight. Similarly, the Board finds the April 2021 statement from the VA physician carries less probative value as he presents no supporting rationale for the conclusory statement. Prejean v. West, 13 Vet. App. 444 (2000). Meaning, absent a detailed discussion of the Veteran's in-service and post-service history in formulating his conclusion, the Board assigns significantly less probative value to this opinion. Consequently, the Board assigns less probative value to March and April 2021 statements submitted by the Veteran. Further, the Board recognizes the Veteran's personal assertions that his degenerative disc disease of the lumbar spine is related to service or his service-connected bilateral knee disability. While the Veteran is certainly capable of describing the medical history and competent to report symptoms observable to a layperson, he is not competent to independently opine as to the specific etiology of a claimed disability or render a medical nexus of a disability to service or a service-connected disability, as such requires medical expertise and the ability to interpret diagnostic medical testing, including X-ray imaging. Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007). For this purpose, the Veteran's assertions do not constitute competent medical evidence, and the Board assigns more weight to the VA medical opinions. Furthermore, the Veteran's assertions of ongoing back pain since service, while competent and credible, are outweighed by other probative evidence of record. Post-service treatment records do not document any residual injury due to a MVA and the record shows an extended period after service without any manifestations of the claimed disability. Specifically, the earliest report of low back pain was in 2003, which is approximately 21 years after separation from active duty. Additionally, the earliest medical evidence of mild to moderate degenerative disc disease of the lumbar spine was revealed in X-rays of September 2010, approximately 28 years after discharge from active duty, or approximately 12 years after release from the Reserves. See Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir. 2006) (holding that the Board may weigh the absence of contemporaneous medical evidence as one factor in determining credibility of lay evidence, but the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence); see also Maxson v. Gober, 230 F.3d 1330, 1333 (Fed. Cir. 2000) (the passage of many years between discharge from active service and the medical documentation of a claimed disability is one factor to consider as evidence against a claim of service connection). In addition, the Veteran's degenerative disc disease of the lumbar spine manifested well after one year after the Veteran separated from active service. Although arthritis may be considered a chronic disease for VA purposes, degenerative arthritis was not clinically shown to a compensable degree within one year following the Veteran's discharge from service. See 38 C.F.R. § 3.307(3). There is also no persuasive credible lay evidence that degenerative arthritis manifested to a compensable degree within one year following the Veteran's discharge from service. Id. As discussed in detail above, medical records following service do not reflect any problems related to arthritis or affecting his bones or joints. As such, service connection on a presumptive basis is not warranted under 38 C.F.R. §§ 3.303(b), 3.307, 3.309. Based on a review of the foregoing evidence and the applicable laws and regulations, the Board finds that the preponderance of the evidence is against the Veteran's claim for service connection for degenerative disc disease of the lumbar spine. In reaching this conclusion, the Board has considered the applicability of the benefit-of-the-doubt doctrine; however, as the preponderance of the evidence is against the claim, that doctrine is not helpful to this claimant. See 38 U.S.C. § 5107(b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49, 53-56 (1990). 2. Entitlement to service connection for pes planus. The Board finds service connection for pes planus is warranted. The Veteran contends his flat feet are due to running and marching during training with improperly sized boots. See August 2018 Hearing Transcript at 22. Similar testimony was presented at his recent hearing. See March 2021 Hearing Transcript at 8. The Veteran's testimony of being issued boots that were too small was established as both competent and credible at his August 2018 hearing. See Hearing Transcript at 22. The Army Reserves record shows a diagnosis of "pes planus, mild" indicated on his enlistment examination. See Report of Medical Examination dated October 1989. The Veteran's service treatment record of December 1996 shows an assessment of "flatfeet, possibly symptomatic" with a notation suggesting "podiatry consult". The Veteran's VA treatment records of May 2014 show a diagnosis of pes planus and treatment with orthotics. The record includes a favorable medical opinion from a VA physician dated August 2018 who opined "frequent long runs; long marches and lack of proper footwear while in the military are least as likely causes for [the Veteran's] pes planus." The VA physician indicated that his medical opinion is based on medical expertise as "a board certified Physical Medicine and Rehabilitation physician who has been at the VA for over 10 years." The physician added that he reviewed the Veteran's medical record, radiographs, documented chronic pain in both feet (pes planus) and considered the Veteran's report of seeking medical assistance for bilateral foot pain while in the military. See Statement from VA physician dated August 2018, received October 2018. After his March 2021 Board hearing, the Veteran submitted another statement from the same VA physician dated April 2021. The VA physician again opined that the Veteran's pes planus was at least as likely as not related to his military service. The physician reiterated that his medical opinion was based on review of the Veteran's electronic medical records, treatment history, and personal examination of the Veteran. See Statement from VA physician dated April 2021. Additionally, the Veteran submitted a statement from his treating physician dated March 2021. The record shows a statement from the Veteran's treating physician finding "as likely as not that [the veteran's] time in service in improperly fitted footwear led to acquired pes planus since the patient reports not having flat feet prior to his time in the armed forces." See Statement from J.S.W., M.D. of UNC Health Care dated March 2021. Given the adequate positive medical nexus opinions and competent, credible lay statements of the Veteran, the evidence is at least evenly balanced as to whether the Veteran's pes planus is the result of his ill-fitting boots and foot pain during service. As the reasonable doubt created by this relative equipoise in the evidence must be resolved in favor of the Veteran, entitlement to service connection for pes planus is warranted. 38 U.S.C. § 5107 (b); 38 C.F.R. § 3.102. 3. Entitlement to service connection for a right wrist disability. 4. Entitlement to service connection for bilateral carpal tunnel syndrome. For the reasons below, the Board finds that service connection for a right wrist disability and bilateral carpal tunnel syndrome have not been established. The Veteran contends that his right wrist disability and bilateral carpal tunnel syndrome were caused by the 1980 motor vehicle accident or otherwise related to service. See August 2018 Hearing Transcript at 18. The Veteran also described experiencing intermittent pain and spasms in his wrist during service and chronic wrist pain after service. Id. at 20. Similar testimony was presented at his recent hearing in March 2021. As noted above, the Veteran's report of being in an MVA in 1980 was deemed credible, and positive findings established in prior Board decisions will not be disturbed. By way of history, the Veteran filed his claim for "wrist and hand both (such as repetitive stress, arthritis, and carpal tunnel syndrome)" in August 2011, which was denied by rating action of March 2013. The available Reserves records show the Veteran had a normal periodic examination in August 1989. See Report of Medical Examination of August 1989. He reported "minor soreness in [left and right] wrist upon weather changes." See Report of Medical History dated August 1989. The medical examiner at the time noted, "onset of soreness [and] stiffness of right wrist [and] index finger April '88 following sprain of wrist symptoms appear with weather changes." Id. The record includes the report of a May 2014 VA wrist examination noting a diagnosis of "bone cyst in right wrist." The record shows an October 2016 VA wrist examination indicating other diagnoses of chronic wrist strain with right wrist bone cyst and chronic left wrist strain. In compliance with the Board's recent July 2020 remand, the Veteran was afforded a VA contract examination in August 2020, with a direct service connection medical opinion obtained in September 2020. The examiner found the Veteran's claimed right wrist and carpal tunnel syndrome were less likely than not caused by an MVA in service or any other in-service event. In the rationale, the examiner stated there was "no record of an MVA in 1980 but even if he had a documented MVA in 1980, the veteran never complained of any injury or any residual injury due to an MVA." The examiner added that "[c]arpal tunnel syndrome is most commonly caused by repetitive use, not a single injury which manifests decades after a single event." Further, the examiner pointed out that "[n]erve conduction studies done on 2-9-2018 indicated that the veteran did NOT have carpal tunnel syndrome... The only mention of any wrist condition while [the veteran] was in the Reserves, was on a report of medical history (8-9-1989) in which the veteran stated that he had minor soreness in his wrists with weather changes and this was 7 years after active duty." See VA contract medical opinion dated September 2020. The Board acknowledges the favorable medical opinions submitted by the Veteran. The record includes an August 2018 statement from a VA physician finding "it is at least as likely as not that [the veteran's] in-service motor vehicle accident has led to his chronic wrist pain." See Statement from VA physician dated August 2018, received October 2018. After his March 2021 hearing, the Veteran submitted a statement from his treating physician, J.S.W., M.D., who rendered a statement that "[o]ne could also reason that the chronic knee pain for which he receives disability could make his wrist and back and hand pain and stiffness worse with time." However, the treating physician indicated that his opinion was based on only four clinic encounters with the Veteran whom he treated since 2018, and review of a SSOC dated September 2020. See Statement from J.S.W., M.D. of UNC Health Care dated March 2021. Upon review of the evidence of record, the Board finds that the preponderance of the evidence is against the Veteran's claim of service connection for a right wrist disability and bilateral carpal tunnel syndrome. In so finding, the Board assigns significant probative value to the September 2020 VA contract opinion which is based on a comprehensive review of the Veteran's claims file, consideration of lay evidence of record, and provide well-grounded rationale to support the examiner's conclusion. The examiner provides substantial reasoning and explanation as to why the Veteran's claimed right wrist and carpal tunnel syndrome disabilities are not etiologically related to service. See Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008) (The probative value of a medical opinion comes from its being factually accurate, fully articulated, and having a sound reasoning for the conclusion.). Accordingly, the Board assigns more weight to the September 2020 VA contract opinion. In contrast, the Board finds the August 2018 VA physician's statement carries less probative value as he presents no supporting rationale or clinical data for the conclusory statement. Specifically, the physician provides no discussion of how a single event in service led to the Veteran's chronic wrist pain as the Veteran's Reserve records and post-service treatment records do not document any residual injury due to a motor vehicle accident. Moreover, the physician fails to address the prolonged period without a diagnosis of carpal tunnel syndrome. Similarly, the Board assigns less weight to the March 2021 statement from J.S.W., M.D. The Veteran's treating physician also provides no supporting rationale or clinical data for stating how the Veteran's chronic knee "could" worsen wrist and hand pain. The physician's statement is also prefaced with "could" which is too speculative to establish a medical nexus. Consequently, the Board assigns less probative value to August 2018 and March 2021 statements submitted by the Veteran. In addition, the Board recognizes the Veteran's assertions that his right wrist and carpal tunnel syndrome are related to service. Although the Veteran is certainly capable of describing the history in this case as well as his symptoms in and after service, as a layperson, without any demonstrated, specialized knowledge concerning the etiology of these disabilities, his allegations are not competent evidence of a medical nexus. Furthermore, the Veteran's assertions are outweighed by other probative evidence of record. There is no evidence indicating chronic disabling conditions. As pointed out by the September 2020 VA examiner, nerve impairment studies performed in 2018 found no evidence of carpal tunnel syndrome. Further, the examiner indicated there was only one documented report in the Reserves for "minor soreness in his wrists with weather changes and this was 7 years after active duty." Accordingly, the Veteran's statements do not constitute competent medical evidence and the Board assigns more weight to the medical evidence of record, including the September 2020 VA contract opinion provided by a medical professional. Lastly, as to presumptive service connection based on chronic disease, there is no persuasive evidence of record that shows a diagnosis of carpal tunnel syndrome within one year of separation from the service or that symptoms of the diseases manifested to a compensable degree within a year of his discharge from service. See 38 C.F.R. §§ 3.303(b), 3.309. Accordingly, service connection for carpal tunnel syndrome on a presumptive basis has not been shown and therefore, not warranted. 38 C.F.R. §§ 3.303(b), 3.307, 3.309(a). Based on a review of the foregoing evidence and the applicable laws and regulations, the Board finds that the preponderance of the evidence is against the Veteran's claim for service connection for a right wrist disability and carpal tunnel syndrome. In reaching this conclusion, the Board has considered the applicability of the benefit-of-the-doubt doctrine; however, as the preponderance of the evidence is against the claim, that doctrine is not helpful to this claimant. See 38 U.S.C. § 5107(b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49, 53-56 (1990). 5. Entitlement to service connection for sleep apnea. For the reasons explained below, the Board finds service connection for sleep apnea is not warranted. The Veteran filed his claim for sleep apnea in March 2012 which was denied by rating action of July 2014. At his hearing, the Veteran stated he had "excessive snoring during service" and believes that sleep apnea "initially had its onset in service." See March 2021 Hearing Transcript at 11. Alternatively, he contends that the disorder developed as a result of his inability to exercise due to his service-connected disabilities. Id at 12. Similar testimony was presented at his first hearing held in August 2018. The Veteran's available Reserves service treatment records do not show any complaint, treatment, or diagnosis of sleep apnea or sleep related issues. Post-service VA treatment records shows he was first informed about sleep apnea in January 2008 and formally diagnosed with sleep apnea by a sleep study performed in July 2020. In compliance with the Board's recent July 2020 remand, the Veteran was afforded a VA contract examination in August 2020 and medical opinions obtained in September 2020. As to the theory of direct service connection, the examiner found it less likely than not that sleep apnea was incurred in or caused by service. The examiner noted the Veteran was diagnosed with sleep apnea in 2009. The examiner addressed the Veteran's contention that he had sleep apnea while on active duty, prior to 1984, but the examiner noted that the Veteran's "weight was a healthy 142 pounds in 8-4-1984," which indicates that his obesity did not cause the sleep apnea. The examiner addressed the Veteran's contention that "the knee pain prevented him from exercising which lead [sic] to weight gain but the veteran weighed 176 pounds on 9-25-1996 the same date he indicated he was in good health and denied any medical problems." In fact, the Veteran was noted to be obese at the time without documented knee pain to contribute to this issue. Based on the above reasoning, the examiner concluded there is no evidence of sleep apnea while in service and there is no evidence that the knee pain caused the weight gain. See VA contract medical opinion dated September 2020. Regarding the theory of secondary service connection, the Board relies on the September 2020 VA contract opinion rendered by the same examiner. The examiner opined the Veteran's sleep apnea is less likely than not proximately due to or the result of service-connected frostbite residuals, bilateral upper and lower extremities, and less likely than not proximately due to service-connected bilateral knee disability. In the rationale, the examiner explained that obstructive sleep apnea is due to a physical obstruction of the upper airway. None of the service connected conditions cause a physical obstruction of the upper airway. Id. The examiner added that the Veteran's obesity is less likely than not proximately due to service-connected frostbite residuals, bilateral upper and lower extremities, bilateral knee disability. In the rationale, the examiner noted the Veteran weighed 176 pounds in 1996 with no complaint of joint pain or other condition preventing him from being able to exercise; he weighed 202 pounds in 1997; he weighed 217 in 1999 when seen for bilateral knee pain; the veteran weighed 239 pounds in 2007. Based on the above, the examiner concluded that the Veteran's "obesity perpetuated the increased bilateral knee pain." Id. In addressing aggravation, the examiner opined that the Veteran's claimed sleep apnea was less likely not aggravated beyond its natural progression by any service-connected condition. In the rationale, the examiner added "[p]ain and numbness which occurs in the fingers and toes after 20 minutes of cold exposure would have no bearing on his sleep apnea, nor would the knee pain. Pain in the knees, hands, and feet does not affect a physical obstruction in the upper airway." Id. As to whether sleep apnea underwent any incremental increase in disability, due to a service-connected disability, the examiner indicated that a determination of baseline level of severity could not be established because the "veteran had his first and only sleep study done in 2010... There has not been another sleep study to state that it is any worse." Id. Finally, the examiner added that when considering the veteran's report as true that his sleep apnea began while on active duty, then "the sleep apnea could not have been caused by the excessive weight gain after service." Id. The Board acknowledges a favorable medical opinion submitted by the Veteran. After his March 2021 hearing, the Veteran submitted a statement from his treating physician. The Veteran's treating physician noted consideration of the Veteran's self-report of having had "poor sleep quality and loud snoring during his years in the service but was denied a sleep study until after he left the military." The treating physician opined "[i]t is possible that [the veteran] had obstructive sleep apnea while in the armed services that went undiagnosed until years later." See Statement from J.S.W., M.D. of UNC Health Care dated March 2021. However, the Board finds this statement carries less probative value as the opinion is based on the Veteran's self-reported history and limited to only review of the September 2020 SSOC for background. Further, there is no discussion of the conflicting September 2020 VA medical opinion which was of record at the time or any discussion of the Veteran's secondary service connection contentions. Moreover, the treating physician's statement does not provide the required degree of medical certainty. Thus, the Board assigns significantly less probative value to the March 2021 statement from the Veteran's treating physician. To that end, the Board assigns significant probative value to the September 2020 VA contract opinion. The medical opinion was based on a thorough and comprehensive review of the Veteran's claims file, consideration of lay evidence of record, and provide a comprehensive, well-grounded rationale to support the examiner's conclusions. The examiner in particular provides substantial reasoning and explanation as to why the Veteran's sleep apnea is not etiologically related to service or service-connected disabilities of frostbite residuals, bilateral upper and lower extremities, and bilateral knee disability. Accordingly, the Board finds great probative value in the September 2020 VA contract opinion. Lastly, at his hearing, the Veteran testified he was told by fellow service members of his excessive snoring in service. See August 2018 Hearing Transcript at 11; see also March 2021 Hearing Transcript at 11. At the March 2021 hearing, the Veteran's spouse also presented testimony describing her observations of the Veteran's snoring and breathing problems. Id. at 15. Although the lay witnesses are competent and credible to report symptoms observable to a layperson, the lay statements are not competent to opine on such medical questions of etiology of a medical diagnosis as this requires medical expertise. Moreover, the probative value of the September 2020 VA examiner's opinion outweighs that of the Veteran and lay witnesses, given the absence of any indication of sleep apnea until many years after service, and as the examiner has more education, experience, and training in determining the etiology of a disability. Based on a review of the foregoing evidence and the applicable laws and regulations, the Board finds that the preponderance of the evidence is against the Veteran's claim for service connection for sleep apnea. In reaching these conclusions, the Board has considered the applicability of the benefit-of-the-doubt doctrine; however, as the preponderance of the evidence is against the claims, that doctrine is not helpful to this claimant. See 38 U.S.C. § 5107(b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49, 53-56 (1990). MICHAEL A. HERMAN Veterans Law Judge Board of Veterans' Appeals L. CHU Veterans Law Judge Board of Veterans' Appeals KELLI A. KORDICH Veterans Law Judge Board of Veterans' Appeals Attorney for the Board S. A., 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.