Citation Nr: 21030077 Decision Date: 05/17/21 Archive Date: 05/17/21 DOCKET NO. 13-03 700A DATE: May 17, 2021 ORDER Entitlement to service connection for breathing problems, to include sleep apnea, is denied. Entitlement to service connection for diabetes mellitus, type II, is denied. Entitlement to service connection for a left leg condition is denied. Entitlement to a rating in excess of 40 percent for right peroneal nerve impairment with right foot drop is denied. Entitlement to an initial rating in excess of 20 percent for lumbar spine degenerative arthritis is denied. Entitlement to an initial rating in excess of 10 percent for a right knee condition is denied. Entitlement to a total disability rating based on individual unemployability as due to service-connected disabilities (TDIU) is denied. REMANDED Entitlement to service connection for a left knee condition is remanded. FINDINGS OF FACT 1. The preponderance of the competent evidence does not demonstrate that the Veteran's diagnosed obstructive sleep apnea was incurred in service or was otherwise attributable to an in-service injury, disease or event; moreover, the Veteran did not have a separately diagnosable condition manifested by breathing problems. 2. Diabetes mellitus type II was not present during active duty; was not manifested to a compensable degree within one year from the date of separation from service in August 1984; and diabetes mellitus type II, first diagnosed after service beyond the one-year presumptive period for a chronic disease, is unrelated to an injury, disease, or event of service origin. 3. The competent evidence does not demonstrate that the Veteran had a diagnosable left leg condition distinct from his separately claimed left knee condition, nor did he experience such a condition during the pendency of the appeal or recent to the filing of the claim. 4. For the entirety of the appeal prior to his passing, the Veteran's right lower extremity nerve impairment was predominantly characterized by complete paralysis of the right popliteal nerve, corresponding to the highest possible schedular rating that he had already been awarded; although there is some evidence of sciatic nerve involvement, a separate rating under the diagnostic code for the sciatic nerve for the same symptomatology in the same body part would violate the rule against pyramiding. 5. The Veteran's lumbar spine condition manifested forward flexion of no less than 45 degrees, combined range of motion of the thoracolumbar spine of no less than 80 degrees, and no ankylosis; furthermore, the preponderance of the evidence is against a determination that the Veteran's intervertebral disc syndrome (IVDS) resulted in incapacitation requiring doctor-prescribed bed rest. 6. Prior to May 29, 2012, the Veteran's right knee exhibited flexion limited to no less than 98 degrees; moreover, there was no indication of right knee dislocated semilunar cartilage, ankylosis, limitation of extension or instability. 7. For the pendency of the appeal, the Veteran was not precluded due to the impact of his service-connected disabilities from securing and following substantially gainful employment. CONCLUSIONS OF LAW 1. The criteria for service connection for breathing problems, to include obstructive sleep apnea, have not been met. 38 U.S.C. §§ 1110, 1112, 1116, 1137; 38 C.F.R. § 3.303. 2. The criteria for service connection for diabetes mellitus type II have not been met. 38 U.S.C. §§ 1110, 1112, 1116, 1137; 38 C.F.R. §§ 3.303, 3.307, 3.309. 3. The criteria for service connection for a left leg condition have not been met. 38 U.S.C. §§ 1110, 1112, 1113, 5107; 38 C.F.R. § 3.303. 4. The criteria for entitlement to a rating in excess of 40 percent for right popliteal nerve impairment with foot drop have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 4.3, 4.7, 4.123, 4.124a, DC 8521. 5. The criteria for entitlement to a rating in excess of 20 percent for a lumbar spine degenerative arthritis have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.321 (b)(1), 4.40, 4.45, 4.59, 4.71a, Diagnostic Code 5242. 6. The criteria for entitlement to a rating in excess of 10 percent for a right knee condition are not met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.40, 4.45, 4.59, 4.71a, Diagnostic Codes 5055, 5260-5010. 7. The criteria for entitlement to TDIU on an extraschedular basis have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.340, 3.34, 4.16(a), 4.16(b); Bowling v. Principi, 15 Vet. App. 1, 10 (2001). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty concurrently from February 1976 to November 1978, and from November 1978 to August 1984. He passed away in May 2020, and the Appellant is his surviving parent. These matters were last before the Board in June 2020, whereupon they were dismissed upon the Board's notification of the Veteran's passing. The Appellant filed her request for substitution in June 2020, which was granted by the RO. Service Connection Entitlement to service connection requires evidence of three elements: (1) a current disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship or nexus between the current disability and the disease or injury incurred or aggravated during active service. Shedden v. Principi, 381 F.3d 1163, 1166-67 (Fed. Cir. 2004). Furthermore, certain chronic diseases will be presumed related to service if they were noted as chronic in service; or, if they manifested to a compensable degree within a presumptive period following separation from service; or, if continuity of the same symptomatology has existed since service, with no intervening cause. 38 U.S.C. §§ 1101, 1112, 1113, 1137; Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2012); 38 C.F.R. §§ 3.303(b), 3.307, 3.309(a). 1. Breathing problems, to include sleep apnea The Appellant contends generally that the Veteran had a condition manifested by breathing problems that was attributable to his service. Of note, the Veteran had a confirmed diagnosis of obstructive sleep apnea; furthermore, the Board finds no evidence that the Veteran was ever diagnosed with a separate respiratory condition manifested by the claimed breathing problems distinct from his obstructive sleep apnea. Accordingly, the Board will proceed with an evaluation of the obstructive sleep apnea alone and apart from any other claimed respiratory condition. To that end, the question for the Board is whether obstructive sleep apnea began during service or is at least as likely as not related to an in-service injury, event or disease. The Board concludes that, while the Veteran was diagnosed with and received treatment for obstructive sleep apnea prior to his passing, the preponderance of the evidence is against a finding that the condition began during active service or was otherwise related to an in-service injury, event, or disease. 38 U.S.C. §§ 1131, 5107(b); Holton v. Shinseki, 557 F.3d 1363, 1366 (Fed. Cir. 2009); 38 C.F.R. § 3.303 (a), (d). A review of the Veteran's service treatment records does not reveal any complaints, findings, treatment, or diagnoses relating to obstructive sleep apnea. Specifically, no symptomatology or diagnosis potentially related to the condition was noted on the May 1984 discharge examination. Post-service medical records show that the Veteran reported experiencing sleep disturbances as early as April 2009 and was noted to have suspected sleep apnea by his VA treating physicians. Sleep studies dated in September 2010 and in October 2010 confirmed a diagnosis of obstructive sleep apnea. Subsequent records show continued treatment for obstructive sleep apnea through VA, to include the use of a continuous positive airway pressure machine; however, at no point prior to the Veteran's passing did any of his treating physicians associate the sleep apnea with his service. The Veteran's obstructive sleep apnea was evaluated as part of the May 2011 VA examination, during which the examiner confirmed that the Veteran was diagnosed with the condition via a sleep study in 2010. The examiner did not offer an opinion as to the likely etiology of the obstructive sleep apnea. The Appellant submitted a handwritten letter signed by the Veteran that was received by the Board in February 2021 after his passing wherein he asserted that he snored every night since he was 19 years old and after awoke with a sore throat. He asserted that these symptoms were attributable to his sleep apnea although it was diagnosed many years later. While VA has a duty to provide a medical opinion where there is competent evidence of a current disability and evidence establishing that it may be attributable to service, that is not the case here. McLendon v. Nicholson, 20 Vet. App. 79, 81 (2006); 38 U.S.C. § 5103A (d)(2); 38 C.F.R. § 3.159 (c)(4)(i). Although the Veteran contended that he experienced symptoms of sleep apnea in service, establishing the exact onset and etiology of a disease process such as obstructive sleep apnea requires specialized medical knowledge and is not a matter capable of lay observation. Accordingly, the Veteran's lay statement as to the etiology of his sleep apnea, unsubstantiated as it is by any additional evidence of record, as well as the Appellant's adoption of those contentions, are not competent evidence as to the etiology of the onset and etiology of the obstructive sleep apnea. Jandreau v. Nicholson, 492 F.3d 1372, 1377, 1377 n.4 (Fed. Cir. 2007). As such, in the light of the lack of any additional evidence which suggests that the obstructive sleep apnea was attributable to service, VA does not have an obligation to obtain a medical opinion addressing the likely etiology of the condition. McLendon, supra. In summation, there is no competent evidence that the Veteran's obstructive sleep apnea, first documented over 20 years after service, was either incurred in service or was otherwise related to an injury, disease, or event of service origin. 38 C.F.R. § 3.303 (a), (d). As such, the preponderance of the evidence is against the claim for service connection for obstructive sleep apnea under any applicable theory of entitlement, and the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). 2. Diabetes mellitus, type II The Appellant contends generally that the Veteran had diabetes mellitus, type II that was attributable to his service. The question for the Board is whether diabetes mellitus, type II, manifested to a compensable degree within the applicable presumptive period, or whether the diabetes was incurred in or was otherwise attributable to an in-service injury, event, or disease. After a review of the claims file, the Board concludes that, while the Veteran had diabetes mellitus, type II, it did not manifest to a compensable degree in service or within a presumptive period, and continuity of symptomatology is not established. 38 U.S.C. §§ 1101 (3), 1112, 1113, 1137; Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013); 38 C.F.R. §§ 3.303 (b), 3.307, 3.309(a). Moreover, there was no evidence of the condition during service, nor is there any evidence to support that the condition was otherwise attributable to service. 38 C.F.R. § 3.303 (a), (d). A review of the Veteran's service treatment records does not reveal any complaints, findings, treatment, or diagnoses relating to diabetes mellitus, type II. Specifically, no diabetes symptomatology or diagnosis was noted on the May 1984 discharge examination. Accordingly, service connection for diabetes mellitus, type II on a direct basis pursuant to 38 C.F.R. § 3.303 (a) is denied. Post-service medical records show that the Veteran was evaluated with new onset diabetes in May 2009. Subsequent records show a formal diagnosis of diabetes mellitus, type II and continued treatment for the same. There is no evidence in the claims file to suggest that he developed diabetes prior to his diagnosis in 2009. On this basis, therefore, the Board concludes that the Veteran's diabetes mellitus, type II did not manifest within the applicable one-year presumptive period, and, accordingly, service connection for diabetes mellitus on a presumptive basis as a chronic disease is denied. 38 C.F.R. § 3.307 (a)(3). The Veteran's diabetes mellitus, type II was evaluated as part of the May 2011 VA examination, during which the examiner confirmed that the Veteran was diagnosed through his VA medical treatment provider in 2010. The examiner did not offer an opinion as to the likely etiology of the diabetes mellitus, type II. Once again, although the Veteran contended generally that his diabetes mellitus, type II was attributable to service, establishing the etiology of a disease process such as diabetes mellitus requires specialized medical knowledge and is not a matter capable of lay observation. Accordingly, the Veteran's general lay statement as to the etiology of his diabetes mellitus, type II, as well as the Appellant's adoption of those contentions, are not competent evidence as to the etiology of the diabetes mellitus, type II. Jandreau v. Nicholson, 492 F.3d 1372, 1377, 1377 n.4 (Fed. Cir. 2007). As such, in the light of the lack of any additional evidence which suggests that the diabetes mellitus, type II was attributable to service, VA does not have an obligation to obtain a medical opinion addressing the likely etiology of the condition. McLendon, supra. In summation, there is no competent evidence that the Veteran's diabetes mellitus, type II, first documented after service beyond the one-year presumptive period, was otherwise related to an injury, disease, or event of service origin. 38 C.F.R. § 3.303 (d). As such, the preponderance of the evidence is against the claim for service connection for diabetes mellitus, type II under any applicable theory of entitlement, and the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). 3. Left leg condition The Appellant contends that the Veteran had a left leg condition distinct from his separately claimed left knee condition that was either directly attributable to service or was secondary to a service-connected disability. Without delving into the question of the potential etiology of the claimed left leg condition, the Board finds that the Veteran was never diagnosed with a left leg condition and there is no evidence to suggest that such a diagnosis would have been appropriate; as such, entitlement to service connection must be denied. A review of available VA and private medical records does not reflect that the Veteran was ever diagnosed with or treated for a left leg condition distinct from his left knee degenerative arthritis. The problem list associated with the Veteran's most contemporary VA medical records prior to his passing does not show a current diagnosis of a left leg condition. A December 2019 outpatient note reflects that the Veteran underwent a musculoskeletal and neurological evaluation which revealed no abnormalities of the left lower extremity. Earlier records also do not show a diagnosis of a chronic left leg condition. During the May 2011 VA examination, the chosen VA examiner found no pathology to render a diagnosis of a left leg condition; as such, they declined to endorse a diagnosis of a left leg condition, and furthermore did not offer an opinion as to the likely etiology of the claimed left leg condition. Similarly, on both the July 2015 VA spine examination as well as the July 2015 VA peripheral nerves examination the VA examiner found no evidence of a left leg condition, and so declined to endorse any diagnosis of such a condition. Ultimately, there is no competent evidence that the Veteran had a left leg condition distinct from his left knee condition, or symptomatology that suggests that a diagnosis of such a condition would be appropriate. The Board highlights the multiple VA examinations of record, none of which revealed any evidence of a diagnosable left leg condition; as these examinations were based on in-person evaluations coupled with a thorough review of the claims file, the Board finds them highly probative. Sklar v. Brown, 5 Vet. App. 140 (1993). Accordingly, without supporting records, the Board finds that the Veteran did not have a diagnosable left leg condition and did not have such a condition during the appeal period prior to his passing. The Veteran did not have the medical training or credentials to offer an opinion as to a diagnosis or its etiology. Jandreau, supra. Service connection is denied for a left leg condition. Brammer v. Derwinski, 3 Vet. App. 223, 225 (1992). As the preponderance of the evidence is against the Veteran's claim, the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). Increased Ratings Disability evaluations are determined by the application of the VA's Schedule for Rating Disabilities (Schedule), 38 C.F.R. Part 4. The percentage ratings contained in the Schedule represent, as far as can be practicably determined, the average impairment in earning capacity resulting from diseases and injuries incurred or aggravated during military service and their residual conditions in civil occupations. 38 U.S.C. § 1155; 38 C.F.R. § 4.1. In determining the disability evaluation, VA has a duty to acknowledge and consider all regulations that are potentially applicable through the assertions and issues raised in the record, and to explain the reasons and bases for its conclusions. Schafrath v. Derwinski, 1 Vet. App. 589 (1991). In determining the appropriate rating for musculoskeletal disabilities, particular attention is focused on functional loss of use of the affected part. Factors of joint disability include increased or limited motion, weakened movement, excess fatigability, incoordination, and painful movement, including during flare-ups and after repeated use. DeLuca v. Brown, 8 Vet. App. 202, 206-08 (1995); 38 C.F.R. § 4.45. A finding of functional loss due to pain must be supported by adequate pathology and evidenced by the visible behavior of the claimant. 38 C.F.R. § 4.40. Additionally, "pain itself does not rise to the level of functional loss as contemplated by the VA regulations applicable to the musculoskeletal system." Mitchell v. Shinseki, 25 Vet. App. 32, 38 (2011). Pain in a particular joint may result in functional loss, but only if it limits the ability to perform the normal working movements of the body with normal excursion, strength, speed, coordination, or endurance. Id.; 38 C.F.R. § 4.40. Under 38 C.F.R. § 4.59, painful joints are entitled to at least the minimum compensable rating for the joint. 1. Right peroneal nerve impairment with right foot drop The Veteran was in receipt of a 40 percent rating for right peroneal nerve impairment with right foot drop. The Appellant seeks an increased rating for the condition for the entirety of the appeal. The right peroneal nerve impairment rating was assigned pursuant to 38 C.F.R. § 4.124a, Diagnostic Code 8521, corresponding to the external popliteal nerve. Under Diagnostic Code 8521, a 40 percent rating is the maximum schedular rating available, and is awarded for complete paralysis and/or foot drop. As such, the Veteran could not receive a higher schedular rating for this condition under the currently assigned diagnostic code. Furthermore, the Board is not aware of the Veteran or the Appellant having contended that an extraschedular rating is warranted for the right peroneal nerve impairment; accordingly, the Board need not address whether such a rating is warranted. See Doucette v. Shulkin, 28 Vet. App. 366 (2017). That being said, the Board does find it prudent to address the propriety of the 40 percent rating that was in effect for the right peroneal nerve impairment if only to satisfy the intentions of the late Veteran prior to his passing. It is noted that the 40 percent rating has been effective since May 9, 1986; as such, it has been in effect for over 20 years, and cannot be reduced. 38 C.F.R. § 3.951 (b). Moreover, the Board also notes that if there was evidence of sciatic nerve involvement of the right lower extremity, then a higher rating would be available under Diagnostic Code 8520, which provides for a 60 percent rating for severe incomplete paralysis with marked muscle atrophy and an 80 percent rating for complete paralysis of the sciatic nerve. During the appeal period, the Veteran was afforded a VA peripheral nerve examination in June 2009, during which he was shown to exhibit complete paralysis of the right peroneal nerve. The examiner further noted that the Veteran exhibited limitations with standing and walking and was only able to walk one quarter mile at a time. The examiner also confirmed that the popliteal nerve was the only nerve involved. The Veteran was next afforded a VA examination to evaluate the right popliteal nerve impairment in May 2011, whereupon he again reported difficulty with ambulation due to right foot drop. According to the Veteran he could walk 500 feet at most without resting. An in-person evaluation revealed some reduced sensation in the right foot although the Veteran still exhibited significant weakness. Once again, the only nerve implicated was the popliteal nerve. The most contemporaneous VA examination of record to evaluate the severity of the right popliteal nerve impairment is dated in July 2015. An in-person evaluation revealed moderate right lower extremity pain and paresthesias, no reduction in right lower extremity muscle strength or reflexes, and decreased sensation in the right foot. The examiner found evidence of mild incomplete paralysis of the right sciatic nerve and no involvement of the right peroneal nerve. In summation, the examiner found that the condition contributed to limited physical activity due to range of motion loss and/or pain during flare-ups. A review of available VA medical records does show continued treatment for right lower extremity impairment with foot drop throughout the appeal period prior to the Veteran's passing. There is no indication from these records that the Veteran was ever evaluated as exhibiting impairment of the sciatic nerve. Based on the results of the July 2015 examination alone, the Board finds that the examiner's determination that the right lower extremity nerve impairment had shifted from involvement of the popliteal nerve to involvement of the sciatic nerve does suggest that the severity of the condition had improved as it had changed from complete paralysis of the popliteal nerve to only mild incomplete paralysis of sciatic nerve. Of note, such an evaluation would correspond to just a 10 percent rating under Diagnostic Code 8520. Moreover, a separate rating under 8520 is not warranted as there is no further evidence of sciatic nerve involvement and the July 2015 examiner found that the right lower extremity nerve impairment had changed to sciatic nerve involvement rather than adding the sciatic nerve involvement. Therefore, providing for a separate rating under 8520 would violate the rules against pyramiding as it would be compensating the Veteran twice for the same disability. 38 C.F.R. § 4.14. Regardless, the Board reiterates that the 40 percent rating that was in effect at the time of the Veteran's passing is not subject to reduction despite the apparent improvement in symptomatology evidenced by the July 2015 VA examination. See 38 C.F.R. § 3.951 (b). Thus, although a higher rating is not warranted, and an additional rating under Diagnostic Code 8520 is also not warranted, the currently assigned 40 percent rating will not be impacted. Any claim of increase, however, is denied. As the preponderance of the evidence is against the Veteran's claim, the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). 2. Lumbar spine degenerative arthritis The Veteran was in receipt of a 20 percent initial rating for lumbar spine degenerative arthritis. The Appellant seeks a rating in excess of that 20 percent for the entirety of the appeal period. Spinal conditions are evaluated under either the General Rating Formula for Diseases and Injuries of the Spine (General Rating Formula) or under the Formula for Rating Intervertebral Disc Syndrome Based on Incapacitating Episodes (Formula for Rating IVDS), whichever method results in the higher evaluation when all disabilities are combined. 38 C.F.R. §§ 4.25, 4.71a, Diagnostic Code 5242. The General Rating Formula provides for a 20 percent rating with forward flexion of the thoracolumbar spine greater than 30 degrees but not greater than 60 degrees; or, the combined range of motion of the thoracolumbar spine not greater than 120 degrees; or, muscle spasm or guarding severe enough to result in an abnormal gait or abnormal spinal contour such as scoliosis, reversed lordosis, or abnormal kyphosis. A 40 percent rating is assigned for forward flexion of the thoracolumbar spine 30 degrees or less; or, favorable ankylosis of the entire thoracolumbar spine. A 50 percent rating is assigned for unfavorable ankylosis of the entire thoracolumbar spine. A 100 percent rating is assigned for unfavorable ankylosis of the entire spine. 38 C.F.R. § 4.71a, General Rating Formula for Diseases and Injuries of the Spine. For VA compensation purposes, normal forward flexion of the thoracolumbar spine is zero to 90 degrees, extension is zero to 30 degrees, left and right lateral flexion are zero to 30 degrees, and left and right lateral rotation are zero to 30 degrees. The combined range of motion refers to the sum of the range of forward flexion, extension, left and right lateral flexion, and left and right rotation. The normal combined range of motion of the thoracolumbar spine is 240 degrees. 38 C.F.R. § 4.71a, General Rating Formula, Note (2); see also 38 C.F.R. § 4.71a, Plate V. According to the Formula for Rating IVDS, a 20 percent rating requires evidence of incapacitating episodes having a total duration of at least two weeks but less than four weeks during the past twelve months; a 40 percent rating requires evidence of incapacitating episodes having a total duration of at least 4 weeks but less than 6 weeks during the past 12 months; and a 60 percent rating requires evidence of incapacitating episodes having a total duration of at least 6 weeks during the past 12 months. 38 C.F.R. § 4.71a, Formula for Rating IVDS. An "incapacitating episode" is defined as a period of acute signs and symptoms due to intervertebral disc syndrome that requires bed rest prescribed by a physician and treatment by a physician. Id. at Note (1). If IVDS is present in more than one spinal segment, provided that the effects in each spinal segment are clearly distinct, each segment will be evaluated on the basis of incapacitating episodes or under the General Rating Formula for Diseases and Injuries of the Spine, whichever method results in a higher evaluation for that segment. Id. at Note (2). During the appeal period, the Veteran was first afforded a VA examination to evaluate the nature and severity of his lumbar spine condition in May 2011, during which he reported experiencing chronic low back pain radiating down the back of his legs. He also endorsed experiencing flare-ups of additional pain and lower extremity weakness. According to the Veteran he experienced functional impairment in the form of incoordination, slow ambulation, inability to lift over 25 pounds of weight, and limited ability to bend. Range of motion testing revealed flexion limited to 70 degrees, extension limited to 10 degrees, bilateral lateral flexion limited to 15 degrees, and bilateral lateral rotation limited to 15 degrees. There was no additional loss of range of motion during repetitive testing; furthermore, the examiner did not find that the joint function ing the spine was additionally limited by pain, fatigue, weakness, lack of endurance or incoordination after repetitive use. While the examiner found evidence of right lower extremity neurological symptomatology, there was no evidence of left lower extremity neurological symptomatology. The examiner also noted that there was IVDS but did not find that the IVDS necessitated doctor-prescribed bed rest in the past year. In summation, the examiner found that the lumbar spine condition resulted in limited bending, lifting, and prolonged ambulation, and contributed to restrictions in the Veteran's ability to carry out physical labor. The severity of the lumbar spine condition was also evaluated in a July 2015 VA spine examination, during which the Veteran endorsed experiencing flare-ups of increased pain with activity and decreased range of motion of the lower back. Range of motion testing revealed flexion limited to 45 degrees, extension limited to 5 degrees, bilateral lateral flexion limited to 5 degrees, and bilateral lateral rotation limited to 10 degrees. There was no additional loss of range of motion during repetitive testing; however, the examiner did note that the Veteran would exhibit additional functional limitations following repetitive use in the form of less movement, weakened movement, and pain on movement. Sensory and reflex testing revealed moderate pain in the right lower extremity; the examiner set forth a diagnosis of moderate right lower extremity radiculopathy with sciatic nerve involvement. The examiner also noted that there was IVDS contributing to incapacitating episodes of at least 6 weeks that required doctor-prescribed bed rest. In summation, the examiner found that the lumbar spine condition contributed to occupational impairment in the form of limited physical activity due to range of motion loss and/or pain during flare-ups. The claims file contains a copy of a correspondence from the Veteran's treating physician, a Dr. A.S., dated in January 2011. Dr. A.S. stated that the Veteran could not stand or sit for more than 10 or 15 minutes at a time without experiencing significant low back pain; she also related that the Veteran reported experiencing back pain with walking. In her opinion, the lumbar spine symptomatology contributed to the Veteran's inability to sustain gainful employment. A review of available VA medical records shows that the Veteran received treatment for low back pain for the entirety of the appeal period prior to his passing. The Board notes that IVDS was not listed in the Veteran's active problem list, and he was never diagnosed with IVDS by any of his treating physicians. Moreover, there is no indication from the available VA medical records that the Veteran was ever prescribed bed-rest by any of his treating physicians. A review of the most contemporary available VA medical records dated in December 2019 and in February 2020 show that the Veteran was evaluated as exhibiting full range of motion despite experiencing low back pain. Upon review of the record, the Board does not find that a rating in excess of 20 percent is warranted for the lumbar spine condition at any point during the appeal period. Range of motion testing on both the May 2011 and July 2015 VA examinations did not reveal forward flexion reduced to 30 degrees or less or favorable ankylosis of the entire thoracolumbar spine. Although the July 2015 examiner did endorse that the Veteran had IVDS resulting in incapacitating episodes necessitating six or more weeks of doctor-prescribed bed rest, the Board could find no contemporaneous medical records to substantiate this finding. Indeed, musculoskeletal evaluations during the year immediately prior to the July 2015 examination revealed that the Veteran's range of motion testing results did not reflect any abnormalities; moreover, the Veteran was not even diagnosed with IVDS by his treating physicians during this time. As such, the Board finds that the preponderance of the evidence is against a determination that the Veteran experienced the incapacitating episodes of IVDS detailed by the July 2015, and as such a rating in excess of 20 percent under either the General Rating Formula or the Formula for Rating IVDS is not warranted. The Board has reviewed the Veteran's lay testimony, the VA treatment records in the claims file, as well as Dr. A.S.'s January 2011 correspondence, but this evidence does not tend to show that the symptoms of the lumbar spine condition warranted a rating in excess of 20 percent. As stated, for any additional functional loss to warrant a higher rating, that loss must rise to the level of the more severe symptomatology represented by the ratings in excess of those assigned percent and/or must reflect additional symptomatology not encompassed within the current assigned ratings which is sufficient to be rated separately, none of which has been shown. Furthermore, although the Veteran reported experiencing flare-ups of pain on both VA examinations, there is no indication from the Veteran's testimony or Dr. A.S.'s correspondence that his flare-ups of symptomatology ever approximated flexion reduced to 30 degrees or favorable ankylosis of the entire thoracolumbar spine, as would be necessary for an evaluation in excess of the currently assigned rating or which would warrant a separate rating. Sharp v. Shinseki, 29 Vet. App. 26 (2017); Correia v. McDonald, 28 Vet. App. 158 (2016). The Board acknowledges the Veteran's statements regarding the pain and stiffness he experienced in his low back. However, painful motion and stiffness are contemplated and compensated by the 20 percent rating currently assigned. DeLuca, supra. Moreover, the evidence of record does not show objective neurologic abnormalities associated with the Veteran's low back condition other than the right popliteal nerve impairment for which the Veteran is already being separately compensated. There is accordingly no basis for separate evaluations for any such disorders. 38 C.F.R. § 4.71a, General Rating Formula, Note (1). As the preponderance of the evidence is against the Veteran's claim, the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). 3. Right knee condition The Veteran was in receipt of a 10 percent initial rating for right knee osteoarthritis. The Appellant seeks a rating in excess of that 10 percent for the entirety of the appeal period. The 10 percent rating was assigned pursuant to 38 C.F.R. § 4.71a, 5260-5010. In the selection of code numbers assigned to disabilities, injuries will generally be represented by the number assigned to the residual condition on the basis of which the rating is determined. With injuries and diseases, preference is to be given to the number assigned to the injury or disease itself; if the rating is determined on the basis of residual conditions, the number appropriate to the residual condition will be added, preceded by a hyphen. 38 C.F.R. § 4.27. The hyphenated diagnostic code in this case indicates that the symptomatology of the right knee osteoarthritis was manifested as limitation of flexion pursuant to Diagnostic Code 5260, with Diagnostic Code 5010 representing traumatic arthritis generally. Diagnostic Code 5010 provides that traumatic arthritis will be rated as analogous to degenerative arthritis under Diagnostic Code 5003. Under Diagnostic Code 5003, where limitation of motion is noncompensable under the appropriate diagnostic code, a rating of 10 percent may be applied to each such major joint or group of minor joints affected by limitation of motion. The limitation of motion must be objectively confirmed by findings such as swelling, muscle spasm, or satisfactory evidence of painful motion. Furthermore, a 20 percent rating is warranted for x-ray evidence of arthritis with evidence of involvement of 2 or more major joints or 2 or more minor joint groups, with occasional incapacitating exacerbations. 38 C.F.R. § 4.71a, Diagnostic Code 5003, 5010. The 20 percent and 10 percent ratings based on x-ray findings will not be combined with ratings based on limitation of motion. Id., Note 1. In addition, the 20 percent and 10 percent ratings based on x-ray findings will not be utilized in rating conditions listed under diagnostic codes 5013 to 5024. Id., Note 2. Before evaluating the propriety of the Veteran's disability rating for the right knee osteoarthritis, the Board notes that during the pendency of the appeal, the rating criteria for evaluating musculoskeletal disabilities under 38 C.F.R. § 4.71a were amended effective February 7, 2021. 85 Fed. Reg. 230 (Nov. 30, 2020). These amendments revised select diagnostic codes "to ensure that this portion of the rating schedule uses current medical terminology and provides detailed and updated criteria for the evaluation of musculoskeletal disabilities." Id. Of import, the diagnostic code for evaluating musculoskeletal conditions under 5010 was revised to specify that this evaluation is to be used solely for the evaluation of post-traumatic arthritis as opposed to degenerative arthritis. Restricting the definition of Diagnostic Code 5010 ultimately serves only to preclude the assignment of a 10 percent rating pursuant to Diagnostic Code 5003 where there is noncompensable limitation of motion. The Board will consider additional diagnostic codes pertinent to the evaluation of knee disabilities in order to determine the highest possible evaluation for the right knee condition during the entire period of the appeal. In considering the applicability of the remaining available diagnostic codes, the Board finds that Diagnostic Codes 5256 (ankylosis), 5257 (instability), 5258 (dislocated semilunar cartilage), 5259 (symptomatic removal of semilunar cartilage), 5262 (disability of the tibia and fibula), and 5263 (genu recurvatum) are not applicable in this instance as the medical evidence does not show that the Veteran experiences these conditions in the right knee. 38 C.F.R. § 4.71a, Diagnostic Codes 5256, 5257 (both prior to an since February 7, 2021), 5258, 5259, 5263. Under Diagnostic Code 5260, limitation of flexion of the leg, a noncompensable rating is assigned when flexion is limited to 60 degrees; a 10 percent rating is assigned when flexion is limited to 45 degrees; a 20 percent rating is assigned when flexion is limited to 30 degrees; and a 30 percent rating is assigned when flexion is limited to 15 degrees. Under Diagnostic Code 5261, limitation of extension of the leg, a noncompensable rating is assigned when extension is limited to 5 degrees; a 10 percent rating is assigned when extension is limited to 10 degrees; a 20 percent rating is assigned when extension is limited to 15 degrees; a 30 percent rating is assigned when extension is limited to 20 degrees; a 40 percent rating is warranted for extension limited to 30 degrees; and a 50 percent rating is assigned when extension is limited to 45 degrees. The standardized description of joint measurements is provided in Plate II under 38 C.F.R. § 4.71a. For VA purposes, "normal" extension and flexion of the knee is from zero to 140 degrees, and references to normal motion below indicate that the Veteran, in fact, had motion from zero to 140 degrees. 38 C.F.R. § 4.71a, Plate II. The VA General Counsel has held that a knee disability may receive separate ratings under diagnostic codes evaluating instability (Code 5257) and those evaluating range of motion (Codes 5003, 5010, 5256, 5260, and 5261). See VAOPGCPREC 23-97. The Board additionally notes that separate ratings under Diagnostic Codes 5260 and 5261 may be assigned for disability of the same knee joint. See VAOPGCPREC 9-2004. The Veteran was first afforded a VA examination to evaluate the nature and severity of his right knee condition in May 2011, during which he reported experiencing weakness, stiffness, swelling, giving way, lack of endurance, locking, fatigability and pain. He also endorsed experiencing flare-ups of additional pain precipitated by physical activity and contributing to painful ambulation and limitation of range of motion. That being said, the Veteran additionally detailed that he did not believe that he experienced any overall functional impairment from his right knee condition. Range of motion testing revealed right knee flexion reduced to 90 degrees, and no loss of extension or ankylosis. The examiner did note evidence of pain following repetitive motion, but there was no additional limitation after repetitive motion testing; furthermore, the examiner noted that joint function was not additionally limited by pain, fatigue, weakness, lack of endurance, or incoordination after repetitive use. An x-ray examination revealed degenerative arthritis with reduced range of motion. The Veteran was next afforded a VA knee examination in July 2015, during which he reported experiencing flare-ups of pain and reduced range of motion precipitated by physical activity. Range of motion testing revealed right knee flexion reduced to 90 degrees, with no loss of extension, instability or ankylosis. The examiner did note evidence of crepitus and pain with weightbearing. There was no additional limitation after three repetitions of range of motion; furthermore, the examiner found no additional limitation during a flare-up of symptomatology. In summation, the examiner found that the right knee condition contributed to impairment of occupational functioning in the form of limited activity due to range of motion loss and/or pain during a flare-up. A review of post-service VA medical records shows that the Veteran received treatment for right knee osteoarthritis symptoms of pain and weakness for the entirety of the appeal period prior to his passing. A March 2009 outpatient record shows that right knee osteoarthritis had been listed as an active problem in the Veteran's VA medical records since April 2004. Subsequent records indicate that the Veteran was prescribed hinged knee braces for use with both knees. He also underwent periodic cortisone injections to relive knee pain. Upon review of the record, the preponderance of the evidence is against a determination that an increased rating is warranted for the Veteran's right knee condition. At no point during the appeal period did the Veteran exhibited flexion limited to 30 degrees, which would be necessary for a 20 percent rating under Diagnostic Code 5260. Moreover, at no point did the Veteran exhibit any limitation of extension, and so a separate rating under Diagnostic Code 5261 is also not warranted. Additionally, no instability or ankylosis were reported on either VA examination or on any medical records, and so a separate rating for such impairment is similarly not warranted. The provisions of the amendments to 38 C.F.R. § 4.71a apply to claims pending before the Board prior to February 7, 2021 that have not been decided as of that date. When electing whether to apply the amended criteria or the criteria previously in place, the Board will apply those criteria that are most beneficial to the Veteran. Although Diagnostic Codes 5260 and 5261 were not changed by the amendments, application of those criteria results only in a noncompensable rating. As such, the current 10 percent rating is based on application of the criteria for rating traumatic arthritis under Diagnostic Code 5010, which allows for a 10 percent rating as analogous to Diagnostic Code 5003. The Board previously detailed that the recent amendments eliminated this alternative avenue for entitlement to a compensable rating under Diagnostic Code 5010. Accordingly, the Board will apply the previous criteria for rating traumatic arthritis under Diagnostic Code 5010 to allow for this 10 percent rating. That being said, even if the Board applies the previous criteria, there is no support for a grant of an increase to a 20 percent rating, which would require x-ray evidence of arthritis with involvement of 2 or more major joints, and is not reflected in the record. 38 C.F.R. § 4.71a, Diagnostic Code 5003, 5010. The Board has reviewed the Veteran's lay testimony and the VA treatment records in the claims file, but this evidence does not tend to show that the symptoms of the right knee condition warranted a rating in excess of 10 percent at any point during the appeal period. As stated, for any additional functional loss to warrant a higher rating, that loss must rise to the level of the more severe symptomatology represented by the ratings in excess of those assigned and/or must reflect additional symptomatology not encompassed within the current assigned ratings which is sufficient to be rated separately, none of which has been shown. Furthermore, although the Veteran reported experiencing flare-ups of right knee symptomatology on both the May 2011 and July 2015 VA examinations, both VA examiners did not find evidence to support a determination that the Veteran would exhibit any additional loss of range of motion during a flare-up of knee symptomatology. While the Board acknowledges that the Veteran reported that he would experience increased pain and loss of range of motion during flare-ups, there is no indication that this increase in symptomatology during flare-ups would be so significant as to equate to flexion reduced to 30 degrees, as would be necessary for an evaluation in excess of the currently assigned ratings or which would warrant a separate rating. Sharp, supra; Correia v. McDonald, 28 Vet. App. 158 (2016). The Board acknowledges the Veteran's statements regarding the pain he experienced in his right knee. However, painful motion is contemplated and compensated by the 10 percent rating currently assigned. DeLuca, supra. Therefore, the Board finds that the assigned 10 percent rating for a right knee condition contemplates the impaired motion exhibited by the Veteran during the appeal period prior to his passing. As the preponderance of the evidence is against the Veteran's claim, the benefit-of-the-doubt standard of proof does not apply. 38 U.S.C. § 5107 (b). The claim is accordingly denied. TDIU The Appellant contends that the Veteran was entitled to TDIU on account of his service-connected disabilities. VA will grant TDIU when the evidence shows that a veteran is precluded by reason of a service-connected disability or disabilities from obtaining and following substantially gainful employment consistent with his education and occupational experience. See 38 C.F.R. §§ 3.340, 3.341, 4.16. The relevant issue is not whether the veteran is unemployed or has difficulty obtaining employment, but whether the veteran is capable of performing the physical and mental acts required by employment. Van Hoose v. Brown, 4 Vet. App. 361, 363 (1993). Advancing age, any impairment caused by conditions that are not service-connected, and prior unemployability status must be disregarded when determining whether a veteran is currently unemployable. 38 C.F.R. §§ 4.16 (a), 4.19. TDIU may be assigned when the schedular rating is less than total, where, if there is only one disability, the disability is rated at 60 percent or more, or where, if there are two or more disabilities, at least one disability is rated 40 percent or more and there is sufficient additional disability to bring the combined rating to 70 percent or more. 38 C.F.R. § 4.16 (a). At the time of his passing, the Veteran was service connected for right peroneal nerve impairment with right foot drop rated as 40 percent disabling, degenerative arthritis of the lumbar spine rated as 20 percent disabling, and right knee osteoarthritis rated as 10 percent disabling. The total combined evaluation of the Veteran's service-connected disabilities was 60 percent. Therefore, the Veteran did not qualify for schedular consideration of TDIU under 38 C.F.R. § 4.16 (a) during any period on appeal. He may still have been entitled to referral for consideration of an extraschedular grant of TDIU, however, if the evidence shows that he was unable to secure or follow a substantially gainful occupation as a result of his or her service-connected disability or disabilities. 38 C.F.R. § 4.16 (b). Where the percentage requirements for TDIU are not met, a total disability rating may nevertheless be assigned on an extraschedular basis when the veteran is unable to secure or follow a substantially gainful occupation as a result of his or her service-connected disability or disabilities. 38 C.F.R. § 4.16 (b). The Board is precluded from assigning a TDIU rating on an extraschedular basis in the first instance. Instead, the Board must refer any claim that meets the criteria for referral for consideration of entitlement to TDIU on an extraschedular basis to the Director of Compensation and Pension Service. See Bowling v. Principi, 15 Vet. App. 1, 10 (2001). Here, the claims file has already been referred to the Director for an evaluation of whether TDIU on an extraschedular basis is warranted. In a June 2017 memorandum, the Director found that TDIU on an extraschedular basis was not warranted. In support thereof, the Director acknowledged that the Veteran had not worked since 2009 and was receiving disability compensation payments from the Social Security Administration since May 2009; however, a review of the available medical evidence, to include the VA examinations of record, did not show that the Veteran's service-connected disabilities precluded employment. Specifically, the Director noted that the Veteran was not shown to require ambulatory aids and further did not require any bed rest to alleviate the symptoms of his service-connected disabilities. The Director also considered the January 2011 opinion of Dr. A. S. regarding the Veteran's unemployability but reiterated that the evidence did not support the determination that TDIU was warranted. In his formal application seeking entitlement to TDIU, dated in August 2009, the Veteran detailed that he ceased working in October 2006 and that he working as a cashier when he became too disabled to work. According to the Veteran, the symptoms of his right popliteal nerve impairment precluded him from maintaining gainful employment. He further reported that he had attained a high school diploma and had no additional training or education. In a November 2009 correspondence, a representative from the Veteran's former employer, McDonalds, indicated that he ceased working at the company in October 2007 when he failed to report for work. The representative did not indicate that the Veteran received any concessions while working as due to his disability or that he ceased working due to his disability. As mentioned, the Veteran submitted a January 2011 correspondence from a Dr. A.S., his treating physician, who noted that the right popliteal nerve impairment with foot drop resulted in an abnormal gait and caused him significant pain requiring opioid therapy for pain control. Dr. A.S. further detailed that the Veteran experienced significant back pain as due to the popliteal nerve impairment. According to Dr. A.S., the Veteran could not walk or sit for extended periods of time; in addition, the Veteran's pain medication interfered with his alertness and ability to concentrate. In summation, Dr. A.S. found that due to the Veteran's physical and mental limitations, it was unlikely that he would be able to sustain gainful employment. Without reiterating the evidentiary record detailed above regarding the Veteran's three service-connected disabilities, the Board does not find that he exhibited symptomatology that in total would have precluded the Veteran from securing and following substantially gainful employment at any point during the appeal period. The VA examiners who have evaluated his various disabilities have each found that the separate service-connected disabilities did not preclude the Veteran from pursuing sedentary employment. Moreover, the Director of Compensation and Pension in the June 2017 correspondence considered all three service-connected disabilities together and concluded that even when evaluated in total they did not contribute to a complete preclusion of gainful employment. Although the Board does acknowledge that Dr. A.S. in her January 2011 correspondence found that the Veteran's popliteal nerve impairment and lumbar spine pain would preclude employment, she appeared to consider the Veteran's "mental limitations" in her calculus of the Veteran's ability to follow and maintain substantially gainful employment. The Veteran was never service-connected for any mental or psychological disability; thus, to conflate the service-connected disabilities with the non-service connected mental health issues the Veteran experienced during his lifetime significantly undermines the reliability of Dr. A.S.'s ultimate conclusion. Therefore, the Board finds that the preponderance of the evidence is against a determination that the Veteran was not precluded by virtue of his service-connected disabilities from securing and following substantially gainful employment. Accordingly, the Appellant's claim seeking entitlement to TDIU on an extraschedular basis is denied. 38 C.F.R. § 4.16 (b). REASONS FOR REMAND Entitlement to service connection for a left knee condition is remanded. A remand to obtain a new medical opinion regarding the etiology of the Veteran's left knee condition is warranted. The Appellant claims that the Veteran's left knee condition is related to service or was caused or aggravated by his service-connected peroneal nerve impairment with foot drop and/or right knee condition. The etiology of the left knee condition was addressed in a July 2015 VA examiner opinion, during which the examiner opined that it was less likely than not that the Veteran had a left knee condition that was caused or aggravated permanently by a service-connected disability. In support thereof, the examiner noted that the Veteran exhibited many of the risk factors for the development of arthritis, to include age, substance abuse history, snoring history, diabetes, smoking history, pes planus, and sleep apnea. However, the examiner also noted additional factors that could lead to the development of arthritis, including gait abnormality and arthritis in other joints. Furthermore, the examiner stated that any of these "risk factors could account for worsening". Unfortunately, the July 2015 examiner employed the incorrect standard in addressing the etiology of the Veteran's claimed left knee condition. In Ward v. Wilkie, the United States Court of Appeals for Veterans Claims held that, for secondary service connection, "aggravation" need not be permanent in nature. 31 Vet. App. 233, 241-42 (2019). Rather "permanently aggravated" is the standard used for service connection of a disorder noted on the medical examination upon entry into service. 38 C.F.R. § 3.306. Indeed, in the Board's estimation, it appears that the examiner did acknowledge some possible aggravation of the left knee condition by both the service-connected peroneal nerve impairment with foot drop as well as the service-connected right knee condition. Therefore, as the examiner employed the incorrect standard, and a positive etiology opinion may be forthcoming under the appropriate standard, a new medical opinion should be obtained on remand. The matter is REMANDED for the following action: 1. Provide the claims file to a qualified medical professional for the purpose of eliciting an opinion as to the etiology of the Veteran's left knee condition. The entire claims file, to include a complete copy of this REMAND, must be made available and that individual must note review of the file prior to setting forth any etiology opinions. The examiner is asked to address the following: (a.) whether it is at least as likely as not (a 50 percent or greater probability) that the left knee condition had onset during service or is otherwise related to active service. (b.) whether it is at least as likely as not that the left knee condition was caused or aggravated by a service-connected disability. If the opinion is that a service-connected disability or disabilities aggravated the left knee condition, the examiner should specify, so far as possible from a review of the record, the degree of disability resulting from such aggravation. The examiner must provide any and all opinions as to etiology in the form of a probability and must provide a complete rationale for any opinion expressed. The permanently aggravated standard should not be employed. Ward v. Wilkie, 31 Vet. App. 233 (2019). 2. THE AOJ MUST REVIEW THE CLAIMS FILE AND ENSURE THAT THE FOREGOING DEVELOPMENT ACTION HAS BEEN COMPLETED IN FULL. IF ANY DEVELOPMENT IS INCOMPLETE, APPROPRIATE CORRECTIVE ACTION MUST BE IMPLEMENTED. IF ANY REPORT DOES NOT INCLUDE ADEQUATE RESPONSES TO THE SPECIFIC OPINIONS REQUESTED, IT MUST BE RETURNED TO THE PROVIDING EXAMINER FOR CORRECTIVE ACTION. T. Berry Acting Veterans Law Judge Board of Veterans' Appeals Attorney for the Board Christopher M. Collins, 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.