Citation Nr: 21073764 Decision Date: 12/10/21 Archive Date: 12/10/21 DOCKET NO. 08-31 838 DATE: December 10, 2021 ORDER Entitlement to service connection for a low back disability is denied. Entitlement to service connection for a left hip disability is denied. Entitlement to service connection for a right hip disability is denied. Entitlement to service connection for bilateral lower extremity sciatica is denied. FINDINGS OF FACT 1. The evidence fails to probatively establish that the Veteran's current low back disability is etiologically or presumptively related to the Veteran's active duty service or is proximately due to, the result of, or aggravated by the Veteran's service-connected bilateral knee disability. 2. The evidence fails to probatively establish that the Veteran's current left hip disability is etiologically or presumptively related to the Veteran's active duty service or is proximately due to, the result of, or aggravated by the Veteran's service-connected bilateral knee disability. 3. The evidence fails to probatively establish that the Veteran's current right hip disability is etiologically or presumptively related to the Veteran's active duty service or is proximately due to, the result of, or aggravated by the Veteran's service-connected bilateral knee disability. 4. The evidence fails to probatively establish that the Veteran's current bilateral sciatica disability is etiologically or presumptively related to the Veteran's active duty service. The condition has been probatively attributed to the Veteran's current low back disability, which is not service-connected. CONCLUSIONS OF LAW 1. The criteria for entitlement to service connection for a low back disability have not been met. 38 U.S.C. §§ 1110, 1112, 1131; 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.310. 2. The criteria for entitlement to service connection for a left hip disability have not been met. 38 U.S.C. §§ 1110, 1112, 1131; 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.310. 3. The criteria for entitlement to service connection for a right hip disability have not been met. 38 U.S.C. §§ 1110, 1112, 1131; 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.310. 4. The criteria for entitlement to service connection for bilateral lower extremity sciatica have not been met. 38 U.S.C. §§ 1110, 1112, 1131; 38 C.F.R. §§ 3.303, 3.307, 3.309. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from December 1959 to July 1965. These matters come before the Board of Veterans' Appeals (Board) on appeal from a November 2009 rating decision issued by a Regional Office (RO) of the United States Department of Veterans Affairs (VA). In the July 2010 VA Form 9, Substantive Appeal, the Veteran declined an optional Board hearing as to these matters. In December 2013, the Veteran's prior attorney requested a Board hearing on the matters. In April 2015, the Veteran's prior attorney requested that the Veteran's hearing request be cancelled. Since then, the Veteran has not submitted any further requests for a Board hearing. See Cook v. Wilkie, 908 F.3d 813 (Fed. Cir. 2018); Quinn v. Wilkie, 31 Vet. App. 284 (2019). The undersigned Veterans Law Judge has been assigned to consider these matters pursuant to 38 C.F.R. § 20.106(a) (formerly 19.3(a)). These matters were previously adjudicated by the Board in a June 2016 decision, which was timely appealed to the United States Court of Appeals for Veterans Claims (Court). In February 2017, the Court issued an Order granting a January 2017 Joint Motion for Partial Remand (JMPR) agreed upon by VA and the Veteran (the parties). In the JMPR, the parties agreed that the Board failed to ensure compliance with its previous November 2012 remand directives insofar as the August 2013 VA medical opinion did not address the aggravation prong of a secondary service connection claim. The matters were remanded by the Board in July 2017, December 2018, and January 2021 in an attempt to obtain an adequate VA medical opinion addressing whether the Veteran's current low back disability and bilateral hip disabilities were aggravated by the Veteran's service-connected bilateral knee disabilities under 38 C.F.R. § 3.310(b). An adequate opinion was received in January 2021 which explained that the Veteran's low back and bilateral hip disabilities have not been aggravated beyond the normal progression of the disorders. In May 2021, the Board remanded the matters in order to obtain additional VA treatment records and all potentially relevant documents scanned into VISTA imaging/Computerized Patient Record System (CPRS). These records were associated with the electronic claims file in August 2021. After a complete review of the electronic claims file, the Board finds there has been substantial compliance with all previous Board remands, and neither the Veteran nor his representative have alleged otherwise. See Stegall v. West, 11 Vet. App. 268, 271 (1998). Neither the Veteran nor his representative has raised any issues with VA's duty to notify or VA's duty to assist in obtaining documentary evidence. See Scott v. McDonald, 789 F.3d 1375, 1381 (Fed. Cir. 2015) (holding that "the Board's obligation to read filings in a liberal manner does not require the Board . . . to search the record and address procedural arguments when the veteran fails to raise them before the Board."); see also Dickens v. McDonald, 814 F.3d 1359, 1361 (Fed. Cir. 2016). Thus, the Board need not discuss any potential issues in this regard. Under 38 U.S.C. § 7104, Board decisions must be based on the entire record, with consideration of all the evidence. The law requires only that the Board address its reasons for rejecting evidence favorable to the Veteran. Timberlake v. Gober, 14 Vet. App. 122, 128-29 (2000). The Board must review the entire record but does not have to discuss each piece of evidence. Gonzales v. West, 218 F.3d 1378, 1381 (Fed. Cir. 2000). The analysis below focuses on the most salient and relevant evidence within the period on appeal and on what this evidence shows, or fails to show, on the claims. The Veteran must not assume that the Board has overlooked pieces of evidence that are not explicitly discussed herein. See Timberlake, supra. Service Connection Service connection will be granted if it is shown that a Veteran has a disability resulting from an injury or disease contracted in the line of duty, or for aggravation of a preexisting injury or disease contracted in the line of duty in the active military, naval, or air service. 38 U.S.C. §§ 1110, 1131; 38 C.F.R. § 3.303. Generally, to establish service connection, a veteran must show: (1) a current disability; (2) an in-service incurrence of a disease or injury; and (3) a causal relationship between the current disability and the disease or injury incurred during service, the so-called "nexus" requirement. See 38 U.S.C. §§ 1110, 1131; 38 C.F.R. § 3.303; see also Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004). All elements must be satisfied before service connection may be achieved. Additionally, service connection may be achieved if any applicable presumptive service connection regulations apply to the Veteran's circumstances or when a claimed disability is shown to be proximately due to, the result of, or aggravated by a service-connected disability. 1. Entitlement to service connection for low back and bilateral hip disabilities is denied. The Veteran has alleged that his current low back disability was incurred during his active duty service, or in the alternative, it is secondary to his service-connected bilateral knee disability. Regarding his bilateral hip disability, he has alleged that this disorder is secondary to his service-connected bilateral knee disability. Direct Service Connection In the August 2016 decision, the Board adjudicated the Veteran's claims under a direct service connection theory of entitlement, and this factfinding was not challenged at the Court or subject to the JMPR. As such, the Board largely reiterates the conclusions reached in the August 2016 Board decision, with additional commentary and analysis. Regarding the current disability element, the record overwhelmingly establishes that the Veteran has been diagnosed with degenerative disc disease of the lumbar spine and degenerative arthritis impacting both sides of the hips. See e.g., September 2019 VA examination. As such, the current disability element of a service connection claim has been satisfied. Regarding in-service incurrence, the Veteran's service treatment records are entirely negative regarding complaints of, treatment for, or diagnoses of any disabilities impacting the low back/lumbar spine or the bilateral hips. The service treatment records show that the Veteran had two episodes of right knee trauma in 1963, the first of which resulted in the Veteran's right knee locking. A right knee arthrotomy was performed in November 1963, where a degenerated partial medial meniscus was removed. The service treatment records mention that the Veteran was admitted to the hospital in June 1964 with a diagnosis of neuroma scar on the right knee. In July 1964, the scar on the medial aspect of the right knee was entirely excised, and tissue which appeared to be a neuroma of the infrapatellar nerve was removed. Post-operatively the Veteran complained of similar pain as preoperatively, but the pain was well away from the new scar. The neuroma in the scar over the medial aspect of the right knee also recurred. Because of his continued complaints, a February 1965 arthrotomy of the right knee was performed with a finding of surgically absent medial meniscus. The postoperative course was without complications. However, on physical examination a small area of hypesthesia was noted on the lateral side of his right knee. The Veteran submitted a statement in April 1965 that since February 1965, the date of his last surgery, he had experienced a "pinched nerve" in the lower part of his right leg. He estimated that this injury occurred during or right after the operation. The location of the injury was the back side of the knee and when he touched the area, an impulse would be sent down the lower part of his leg, across his foot in the direction of the big toe. There was a numb feeling that started about halfway down on the lower part of the right leg and continued across the foot toward the big toe. Many times the area would become quite painful. He also was unable to raise his big toe to the top of his shoe. Another statement submitted by the Veteran in his service treatment records notes that he was given a Physical Evaluation Board in July 1965 and he indicated that he gave sufficient evidence of a pinched nerve in the back of his right knee. He noted that the pinched nerve diagnosis was changed to a sciatic nerve neuralgia, moderate. However, the service treatment records do not actually show any findings of sciatic nerve neuralgia. The report from the Veteran's Physical Evaluation Board is of record and made no reference to any disability impacting the low back or the bilateral hips. To the extent that the Veteran has lay-reported that he injured his low back coincident in time with the initial in-service trauma to his right knee, which allegedly occurred when he slipped from a ladder while aboard the U.S.S. Hermitage in 1963, the Board does not find such lay reports to be credible based on the current evidentiary record. As noted above, the Veteran's service treatment records are entirely negative regarding low back complaints during his active duty service. The Board may weigh a veteran's lay statements against the absence of contemporary corroborating medical evidence. See Buchanan v. Nicholson, 451 F.3d 1331, 1336-37 (Fed. Cir. 2006). However, in doing so, the Board must first establish a proper foundation for drawing inferences against a veteran from an absence of documentation. Fountain v. McDonald, 27 Vet. App. 258 (2015); see also Horn v. Shinseki, 25 Vet. App. 231, 239 (2012). In Horn, the Court held that the absence of evidence cannot be substantive negative evidence without "a proper foundation . . . to demonstrate that such silence has a tendency to prove or disprove a relevant fact." 25 Vet. App. at 239 n.7 ; see also AZ v. Shinseki, 731 F.3d 1303, 1315 (Fed. Cir. 2013) (recognizing the widely held view that the absence of an entry in a record may be considered evidence that the fact did not occur if it appears that the fact would have been recorded if present); Buczynski v. Shinseki, 24 Vet. App. 221, 224 (2011) (when a medical condition or symptom has not been noted in the medical records, the Board may not consider that as negative evidence unless it is the sort of condition or symptom that would normally be noted or reported); Kahana v. Shinseki, 24 Vet. App. 428, 440 (2011) (Lance, J., concurring) (citing Federal Rules of Evidence at 803(7) for the proposition that "the absence of an entry in a record may be evidence against the existence of a fact if such a fact would ordinarily be recorded."). Here, the Veteran's service treatment records document the Veteran's reports of experiencing a right knee injury in 1963 that required specialized orthopedic treatment and surgical intervention. There is no indication from these treatment records that the Veteran experienced any injury to the low back or related symptoms. Had the Veteran actually experienced a low back injury coincident in time with his 1963 right knee injury, as severely as alleged, it is most reasonable to conclude that he would have reported such symptoms to his treating orthopedic specialists, had such symptoms been present, or the specialists would have identified such an injury in their clinical evaluations. This is particularly true since he was being evaluated by orthopedists, who specialize in identifying, evaluating, and treating injuries to the musculoskeletal system, and they were already treating him for similar complaints in the right knee. The absence of this expected evidence weighs against the credibility of the Veteran's lay assertions. Additionally, the Board notes that on multiple occasions throughout the years, when describing the 1963 right knee injury, the Veteran made no reference to similar injury to the low back. For instance, at an October 1990 VA examination, the Veteran provided a medical history regarding his 1963 in-service ladder injury. In his description of the accident, he made no reference to any low back injury. Likewise, in his lay reports to a disability evaluator in November 1993, he reported injuring his right knee in a 1963 in-service ladder accident, but he made no reference to also injuring his low back at that time. In a May 2001 letter to his treating orthopedist, the Veteran provided an extensive narrative of the facts surrounding his 1963 in-service ladder injury, yet again, he made no reference to suffering any injury to the low back at the time of the accident. The Veteran did not begin reporting a low back injury sustained in the 1963 ladder accident until close proximity to the filing of his claim of entitlement to service connection for a low back disability. The timing of these post hoc revisions suggest the influence of interest and a desire for pecuniary gain which significantly impact the credibility of his lay reports describing an in-service incurrence of low back injury. See Cartwright v. Derwinski, 2 Vet. App. 24, 25 (1991) (pecuniary interest may affect the credibility of testimony); see also Caluza v. Brown, 7 Vet. App. 498, 510-511 (1995) (credibility can be generally evaluated by a showing of interest, bias, or inconsistent statements, and the demeanor of the witness, facial plausibility of the testimony, and the consistency of the testimony). The Veteran has not alleged that his bilateral hip disability was incurred during his active duty service and the relevant service department records are negative for bilateral hip complaints or diagnoses. While the Veteran has variably reported the date of onset for his bilateral hip complaints, further calling into question the Veteran's credibility as a reputable medical historian, the record shows he experienced a pelvic fracture coincident in time with a 1973 motorcycle accident, and the earliest onset of chronic bilateral hip symptoms were reported to be in "1970s," after the Veteran's separation from active duty service. See e.g., June 2009 VA examination (reported right hip pain began in 1995 and denied left hip problems); August 2013 VA examination (reported bilateral hip pain began in 1983); see October 2017 VA examination (reported he was started on ibuprofen for hip pain in 1985); September 2019 VA examination (reported he started to have hip pain in the 1970s). Regarding the low back, the Veteran's lay reports of initial onset during service have been deemed to lack credibility under the current evidentiary record and the relevant service department records are negative for in-service low back complaints or diagnosis. The first reference to low back pain in the record dates to 1968 when he injured his low back performing post-service employment as a high pressure welder. Based on the above, the Board finds no probative evidence of record showing in-service incurrence of a low back and/or bilateral hip disability during the Veteran's active duty service, and this requisite element of a direct service connection claim has not been satisfied. Next, the Board turns to the issue of medical nexus. In February 2008, the Veteran submitted two favorable private medical opinions linking his current low back and bilateral hip disabilities to his active duty service (despite the fact that the Veteran, himself, has never directly alleged that he sustained a bilateral hip disability in service). A February 2008 statement from Dr. Gelb notes that he had been treating the Veteran for eight years. The Veteran reportedly injured his knees in service in 1963 when he ran to a ladder, lost his balance and hit the deck. He also reportedly twisted his body to the right. The physician noted that the Veteran complained of knee pain and also had back and hip pain. Dr. Gelb noted that the Veteran had not had any other serious injury to his back aside from the fall of about 5 feet in 1963. The Veteran's most recent magnetic resonance images (MRI) demonstrated significant bilateral recess stenosis and neuroforaminal stenosis at multiple levels. Based on Dr. Gelb's review of the records and examination of the Veteran for the past eight years, Dr. Gelb related the Veteran's back and hip pain to his original injury on the ship in 1963. Dr. Gelb further noted that the Veteran was discharged with a disability rating not only for his knees but also sciatica, indicating that he had injured his lower back or at least the nerves relating to his back. However, the Board accords no probative weight to Dr. Gelb's opinion as such was based on an inaccurate factual premise. See Reonal v. Brown, 5 Vet. App. 458, 461 (1993) (holding that the Board may reject a medical opinion based on an inaccurate factual basis). In this regard, Dr. Gelb indicated that the Veteran had not had any other serious injury to his back aside from the fall of about 5 feet in 1963; however, this explanation failed to account for the Veteran's documented post-service injuries to the back, as documented in the November 1993 State Disability Examination. Specifically, in 1968, the Veteran was working at Caterpillar and was propelled backward as a high pressure welder injuring his low back and was apparently hospitalized for this problem. In 1969, while working at a nuclear power station he had a block of wood drop injuring his back, at which time he was hospitalized again. While working in 1973, a pick-up truck ran a stop sign and hit the Veteran while he was on a motorcycle, throwing him 65 feet from the site of the accident and fracturing his right pelvis. The Veteran also was hit from behind in car accidents in 1974, 1975, 1976, and 2001, reinjuring his low back. See November 1993 disability evaluation; see also January 2019 private orthopedic record. Moreover, to the extent that Dr. Gelb noted that the Veteran was discharged with a disability rating not only for his knees but also sciatica, indicating that he had injured his lower back or at least the nerves relating to his back, such is also incorrect. Rather, service treatment records reflect with a diagnosis of neuroma scar on the right knee as a result of a November 1963 medial meniscectomy, also diagnosed as neuroma of infra patellar nerve. The Veteran's service treatment records are negative for any findings of sciatic nerve neuralgia. Indeed, at a post-service December 1965 VA neurological examination, the Veteran was diagnosed with mild neuropathy impacting the right deep peroneal nerve, and there were no findings consistent with sciatica or impairment of the sciatic nerve. Therefore, as Dr. Gelb based his opinion on an inaccurate factual basis, it is accorded no probative weight in this determination. The Veteran also submitted a statement from Dr. Grigg that was dated in March 2008. Dr. Grigg noted that the Veteran slid down a ladder in service jamming both knees and also had complaints of back pain. He was now having daily back pain in addition to pain in both hips. An MRI of the spine in 2006 reportedly showed severe degenerative disc disease, degenerative arthritis, and spinal stenosis. Dr. Grigg noted that the Veteran had been his patient for the past three years and had been seen on multiple occasions with bilateral hip and back pain requiring cortisone injections, physical therapy, and pain medication. It was Dr. Grigg's professional opinion that the Veteran's present condition, i.e., degenerative disc disease and degenerative arthritis of both hips and spine was related to his military injury sustained in 1963. Dr. Grigg further noted that these injuries have over the last 40 years precipitated the Veteran's back and hip injuries.' With regard to Dr. Grigg's March 2008 opinion, the Board similarly accords it no probative weight as it does not include a rationale for the conclusion reached. In this regard, such opinion simply notes the Veteran's reported in-service injury, current symptoms, and a conclusory statement that the Veteran's degenerative arthritis of both hips and spine is etiologically related to the 1963 in-service injury to the Veteran's right knee, which has in turn, precipitated the Veteran's low back and hip disorders during the intervening 40 years. However, Dr. Grigg did not offer supporting data or a reasoned medical explanation connecting the Veteran's current disabilities to such in-service injury. See Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008); Stefl v. Nicholson, 21 Vet. App. 120, 124 (2007) ("[A]medical opinion . . . must support its conclusion with an analysis that the Board can consider and weigh against contrary opinions"). Furthermore, it is unclear whether he was aware of the Veteran's numerous post-service injuries, as detailed above, as he made no reference to these intercurrent events. Therefore, in light of such deficiencies, the Board accords Dr. Grigg's opinion no probative weight in this determination. In the April 2012 decision, the Board remanded the matters for a VA medical opinion to address the Veteran's less than credible contentions that his current low back and bilateral hip disabilities were etiologically related to his active duty service. The Veteran was afforded a VA examination in August 2013, where diagnoses of degenerative disc disease of the lumbar spine and mild degenerative arthritis of the bilateral hips was confirmed. Following an in-person evaluation and complete review of the available evidence of record, the VA examiner declined to link the Veteran's disabilities to his active duty service. Regarding the bilateral hips, the VA examiner correctly noted that the Veteran's service treatment records and Physical Evaluation Board report were negative for evidence of a bilateral hip disability during service. Similarly, the VA examiner correctly noted evidence in the record indicating that the Veteran suffered a post-service right pelvic fracture in 1973 as a result of a motorcycle accident. The VA examiner further correctly noted that the record was silent regarding clinical evidence of a bilateral hip disability until many years after the Veteran's active duty service. Indeed, a physical examination conducted in February 1989 stated that the Veteran's bilateral hips were noncontributory and exhibited no pain on active straight leg raising and good range of motion. The VA examiner then explained that the Veteran's clinical presentation most correlated with age-related osteoarthritis, entirely unrelated to his active duty service. Regarding the low back, the VA examiner correctly noted that the Veteran's service treatment records and Physical Evaluation Board report were negative for evidence of a low back disability during service. The VA examiner cited several post-service injuries to the Veteran's low back, including a work-related injury in 1969 and several motor vehicle accidents, where it was indicated that the Veteran's low back was injured. The VA examiner opined that the Veteran's low back disability was most likely the result of and accelerated by the Veteran's post-service low back injuries and degenerative scoliosis, entirely unrelated to his active duty service. While subsequent VA examinations tangentially addressed the question of direct service connection, the Board finds the August 2013 VA examination to be the most probative evidence on the issue. The August 2013 VA examiner's opinion was factually accurate and correctly noted that the Veteran's low back and bilateral hip disabilities did not manifest until years after the Veteran's separation from active duty service. The VA examiner considered the pertinent evidence of record available at the time of the opinion, to include the varying lay statements of the Veteran, and the findings upon physical examination of the Veteran. The VA examiner issued medical opinions that were supported by complete rationales based on accurate assessment of the record evidence. Moreover, the VA examiner offered clear conclusions with supporting data, as well as reasoned medical explanations connecting the data to the conclusions with respect to each of the claims. See Nieves-Rodriguez, supra; Stefl, supra. As such, the Board finds the August 2013 VA medical opinions to be the most probative evidence addressing medical nexus in connection with the Veteran's direct service connection claims for a low back and bilateral hip disability. Following a complete review of the electronic claims file, the Board finds no probative evidence that the Veteran sustained any low back or bilateral hip injuries/symptoms during his active duty service, and the most probative medical nexus opinion is that of the August 2013 VA examiner, and it weighs against the claims. Consequently, the Veteran's appeal seeking service connection for a low back and bilateral hip disabilities must be denied under a direct service connection theory of entitlement. Secondary Service Connection The Veteran has also asserted that his current low back and bilateral hip disabilities may be secondary to his service-connected bilateral knee disabilities under 38 C.F.R. § 3.310. There are two possible avenues for entitlement to service connection for a current disability secondary to a service-connected disability; one is based on causation; the other is based on aggravation. See 38 C.F.R. § 3.310(a)(b). In the August 2016 decision, the Board adjudicated the Veteran's claims under a secondary service connection causation theory of entitlement, and this factfinding was not challenged at the Court or subject to the JMPR. Instead, the JMPR focused exclusively on the aggravation prong of a secondary service connection claim. In a June 2009 VA medical opinion, a VA examiner addressed the issue of whether the Veteran's current low back and right hip disabilities were caused by the Veteran's service-connected bilateral knee disability. Following a complete review of the available evidence of record and a physical examination, the VA examiner opined that it was less likely than not that the Veteran's low back and right hip disabilities were caused by his service-connected bilateral knee disability. The VA examiner explained that degenerative changes occur when joints and bones wear down over time and gradually worsen with aging. The VA examiner explained that many post-service back injuries documented in the record likely played a role in accelerating the Veteran's degenerative changes to the lumbar spine over time. As to the right hip, the VA examiner stated that the documented post-service history of injury to the right hip, to include a right pelvic fracture, likely accelerated the degenerative changes present in the right hip. The VA examiner found that the Veteran's bilateral knee disability played no role in the development of the Veteran's low back and right hip disabilities. In addressing whether the Veteran's low back and bilateral hip disabilities were caused by the Veteran's bilateral knee disability, the August 2013 VA examiner cited the same rationale as to why the Veteran's disabilities were not etiologically related to service. The VA examiner found no causal relationship between the Veteran's low back and bilateral hip disabilities and his service-connected bilateral knee disability. Additional VA medical opinions were obtained in October 2017, September 2019, and June 2020. These medical opinions were deemed inadequate by the Board in past remand decisions to the extent that they did not appropriately address the aggravation prong of a secondary service connection claim; however, the Board has elected to discuss these opinions in relation to the Veteran's claims based on a secondary service connection causation theory of entitlement. Likewise, the Board shall address a January 2021 VA addendum opinion in this regard. The October 2017 VA examiner explained that the Veteran's right knee disability was diagnosed in service, his left knee disability was diagnosed many years after service, and his low back disability was first assessed in 1978. The VA examiner found no temporal connection between the knee and back complaints and no medical evidence linking the Veteran's knees to his low back. Regarding the hips, the VA examiner stated that the Veteran did not have physical complaints referrable to the hip joints and the diagnostic imaging showed expected mild degenerative changes to the hip consistent with a person of the Veteran's age. The VA examiner did not directly address whether the Veteran's hip disability was caused by the Veteran's bilateral knee disability. A VA medical opinion was obtained in September 2019; however it is difficult to follow and does not sufficiently address the secondary service connection questions at issue. An addendum opinion was obtained in June 2020, where the VA examiner explained that the weight of the peer-reviewed medical literature was against a cause or effect relationship between the Veteran's current low back disability and his service-connected bilateral knee disability. The August 2016 Board decision was vacated because it did not adequately address whether the Veteran's current low back and bilateral hip disabilities were aggravated by the Veteran's service-connected knee disability. VA medical opinions on this issue were obtained in October 2017, September 2019, and January 2020, but have been determined by past Board remand decisions to be inadequate. Following a January 2021 Board remand, a final addendum medical opinion was obtained in January 2021 which addressed the Veteran's secondary service connection claims. Following a complete review of the electronic claims file, the VA examiner explained that there was no objective evidence that the Veteran's low back or bilateral hip disability was aggravated beyond the normal progression of the disorders. This conclusion is consistent with the other VA medical opinions of record which indicated that the Veteran's low back and bilateral hip arthritis were degenerative in nature and consistent with what would normally be expected in a person of the Veteran's age. Further, the January 2021 VA examiner explained that the Veteran's lumbar spine and bilateral hip arthritis were conditions entirely different and distinct from the Veteran's service-connected bilateral knee disability, and there was no pathophysiological correlation between the Veteran's service-connected bilateral knee disability and the Veteran's disabilities impacting the lumbar spine and bilateral hips. The VA examiner was clear in stating that the weight of the peer-reviewed medical literature was against a relationship of any kind (cause, effect, or aggravation) between the Veteran's service-connected bilateral knee disability and his current disabilities of lumbar spine and bilateral hip degenerative arthritis. The Veteran's secondary service connection claim arises from his lay contention that the Veteran's service-connected knee disability resulted in chronic gait disturbances that caused or aggravated his current low back and bilateral hip disabilities. See e.g., December 2008 lay statement; November 2020 informal hearing presentation. Initially, the Board observes that the Veteran is not competent to opine that his service-connected bilateral knee disability caused or aggravated his current low back and bilateral hip disabilities. As a lay person, the Veteran lacks the medical training and expertise to offer an opinion on a complex medical matter, such as the causes or aggravating factors of a health condition. See Jandreau v. Nicholson, 492 F.3d 1372, 1376-77 (Fed. Cir. 2007). Moreover, the Board finds the Veteran's theory of entitlement to be unsupported by the medical evidence of record, which does not demonstrate a chronic and consistent gait impairment caused by the Veteran's service-connected bilateral knee disability. Assessment of the Veteran's gait in the medical records throughout the appeal period lists the Veteran's gait as steady, normal, or stable far more often than it is listed as impaired, unsteady, or antalgic. Indeed, when the Veteran's gait was noted to be abnormal, this was typically linked to the Veteran's nonservice-connected lumbar spine or right foot disabilities versus the Veteran's service-connected bilateral knee disability. See e.g., January 2018 VA neurological records ("gait disturbance: most likely related to spinal spondylosis and right foot proprioceptive deficits"); June 2011 VA physical medicine records ("gait dysfunction 2nd to L-spine pain"). The Board notes that an August 2013 VA neurological examination stated that the Veteran's antalgic gait was caused by the lumbar spine and right knee instability. The examiner did not explain which condition was more contributory to the Veteran's documented gait impairment. Overall, the medical records do not support the Veteran's lay contention that he experienced a pervasive pattern of constant gait impairment over the years, yet alone one that is solely attributed to his service-connected bilateral knee disability. In adjudicating the Veteran's secondary service connection claim, the Board finds the August 2013 and January 2021 VA medical opinions to be the most probative on the issue of whether the Veteran's current low back and bilateral hip disabilities were related to the Veteran's service-connected bilateral knee disability. These VA examiners clearly and sufficiently explained that the Veteran's conditions were degenerative in nature, with no etiological connection to the Veteran's knees. Likewise, the January 2021 VA medical opinion is highly probative on the issue of whether the Veteran's current low back and bilateral hip disabilities have been aggravated by his service-connected knee disabilities, explaining that the Veteran's disabilities have progressed at the normal rate, and no pathophysiological relationship, including based on aggravation, exists. Indeed, the Board has found the Veteran's primary contention regarding secondary service connection to be unsupported by the medical evidence, which did not show the presence of a pervasive and constant gait impairment attributed to the Veteran's service-connected bilateral knee disability. As the requisite elements have not been satisfied, the Veteran's appeal seeking service connection for a low back and bilateral hip disabilities is denied under a secondary service connection theory of entitlement. Presumptive Service Connection The Board has considered whether the Veteran can achieve service connection for low back and bilateral hip disabilities on a presumptive basis under 38 C.F.R. §§ 3.303(b), 3.307(a)(3), and 3.309(a). Where a veteran served for at least 90 days during a war period or after December 31, 1946, and manifests certain chronic diseases, including arthritis, to a degree of 10 percent within one year from the date of termination of such service, such disease shall be presumed to have been incurred or aggravated in service, even though there is no evidence of such disease during the period of service. 38 U.S.C. §§ 1101, 1112, 1137; 38 C.F.R. §§ 3.307(a)(1)-(3), 3.309(a). Alternatively, service connection may be established under 38 C.F.R. § 3.303(b) when there is (a) evidence of (i) the existence of a chronic disease in service or during an applicable presumption period under 38 C.F.R. § 3.307 and (ii) present manifestations of the same chronic disease, or (b) evidence that an eligible disease is noted in service, but is not, in fact, shown to be chronic or where the diagnosis of chronicity may be legitimately questioned, and there is evidence of continuity of symptomatology after service discharge. However, the use of continuity of symptomatology to establish presumptive service connection is limited only to those diseases listed at 38 C.F.R. § 3.309(a) and does not apply to other disabilities which might be considered chronic from a medical standpoint. See Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). The Veteran did not manifest symptoms of low back or bilateral hip arthritis during service or to a compensable degree within one year of separation from active duty service. Likewise, such conditions were never noted to be present in service, and the Veteran's lay allegations of a low back injury during service have been found to lack credibility. The most probative evidence of record establishes that the Veteran's low back and bilateral hip disabilities first manifested years after separation from service. The Veteran is not entitled to presumptive service connection for low back and/or bilateral hip degenerative arthritis under any of the applicable provisions, and the appeals are denied under this theory of entitlement. 2. Entitlement to service connection for bilateral sciatica is denied. The Veteran contends that his current bilateral sciatica disability was incurred in service or is secondary to his lumbar spine disease. The current disability element of a service connection claim is not in dispute, as the record overwhelmingly establishes a clinical diagnosis of bilateral sciatica during the appellate period. Regarding in-service incurrence, there is no probative evidence establishing that the Veteran's bilateral sciatica was present during service. The Veteran's service treatment records show that the Veteran had a neuroma of the infra patellar nerve associated with right knee surgery in service. However, that condition is shown to have been treated and resolved, and is not shown to be in any way associated with the currently claimed bilateral lower extremity sciatica, with radicular origination from the Veteran's lumbosacral spine condition. In this regard, the Veteran has been diagnosed by numerous health professionals as suffering from degenerative disc disease of the lumbar spine with related bilateral sciatica. Five months after the Veteran's discharge, the Veteran underwent a VA neurological evaluation in December 1965. The Veteran complained of a sharp-like sensation over the lateral aspect of the right knee, and an electric shock going into the right foot and great toe. On neurological examination the Veteran had impaired dorsiflexion of the right toes, especially of the great toe, which was mild. He complained about hypesthesia over the lateral surface of the right leg and foot. Considering the Veteran's history of multiple operations on his right knee for ruptured cartilages and finally a diagnosis of bilateral chondromalacia, the examiner determined that the Veteran had developed a mild neuropathy of the deep peroneal nerve, indicated by a sensory deficit in the distribution of the superficial peroneal nerve and weakness of the extensors of the toes of the right leg. The diagnosis was neuropathy, mild at present, deep peroneal nerve right, secondary to multiple knee operations and chondromalacia. The VA examiner found no neurological disability impacting the sciatic nerve in either lower extremity. As a lay person, the Veteran is not competent to opine that the right lower extremity symptom he experienced in service was due to sciatic nerve impairment, as he lacks the medical training and expertise to offer a valid opinion on medical diagnosis or etiology. Jandreau, supra. In this regard, the Board notes that the contemporaneous medical records and opinions of health providers have explained that the Veteran's in-service right lower extremity symptoms were related to conditions other than sciatic nerve impairment, and there is no medical evidence of record proving that the neuroma of the infra patellar nerve noted in the right leg, as noted in the service treatment records, or the right leg deep peroneal nerve impairment noted in the December 1965 VA neurological examination are present during the appellate period. The most probative evidence of record fails to demonstrate that the Veteran's bilateral sciatica was incurred during his active duty service. Instead, the evidence shows that the Veteran's bilateral sciatica is caused by the Veteran's nonservice-connected low back disability. Since the Veteran is not service connected for a low back disability, service connection for bilateral sciatica on a secondary basis cannot be established. As an "other organic disease[s] of the nervous system," the Board has considered whether the Veteran can achieve service connection on a presumptive basis under the provisions of 38 C.F.R. § 3.303(b), 3.307(a)(3), and 3.309(a). See Walker, supra. The record shows that the Veteran's bilateral sciatica was not present in service and did not manifest to a compensable degree within one year of the Veteran's separation from service. In fact, the record does not show the presence of bilateral lower extremity sciatica until many years after the Veteran's separation from service. Thus, service connection on a presumptive basis is not warranted under the current evidentiary record. In light of the above analysis, the evidence does not support the Veteran's claim of entitlement to service connection for bilateral sciatica under any applicable theories of entitlement. As such, the Veteran's appeal seeking service connection for bilateral sciatica is denied. Cynthia M. Bruce Veterans Law Judge Board of Veterans' Appeals Attorney for the Board M. Galante, 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.