Citation Nr: 21064034 Decision Date: 10/18/21 Archive Date: 10/18/21 DOCKET NO. 17-07 846 DATE: October 18, 2021 ORDER Entitlement to service connection for sleep apnea is granted. Entitlement to an initial disability evaluation in excess of 10 percent prior to March 17, 2020 for right knee limitation of flexion is denied. Entitlement to an initial disability evaluation in excess of 10 percent prior to March 17, 2020 for left knee limitation of flexion is denied. For all times effective March 17, 2020 to the present, an increased rating to 20 percent, but no higher, for right knee limitation of flexion is granted. For all times effective March 17, 2020 to the present, an increased rating to 20 percent, but no higher, for left knee limitation of flexion is granted. For all times effective March 17, 2020 to the present, entitlement to a separate 10 percent rating, but no higher, for limitation of extension of the right knee is granted. For all times effective March 17, 2020 to the present, entitlement to a separate 10 percent rating, but no higher, for limitation of extension of the left knee is granted. For all times effective September 7, 2018 to the present, entitlement to a separate 10 percent rating, but no higher, for right knee instability is granted. For all times effective September 7, 2018 to the present, entitlement to a separate 10 percent rating, but no higher, for right knee instability is granted. FINDINGS OF FACT 1. The evidence of record supports a finding that the Veteran's sleep apnea was caused by obesity due to service-connected disabilities. 2. For the period prior to March 17, 2020, the Veteran's right and left knee flexion was not limited to 30 degrees or less, to include after repeated use or during flare-ups. 3. For the entire period from March 17, 2020 to the present, the Veteran's right and left knee flexion was limited to 30 degrees during flare-ups. 4. For the period from March 17, 2020 to the present, the Veteran's right and left knee extension was limited to 10 degrees during flare-ups. 5. For the entire period from September 7, 2018, the Veteran's right and left knee disabilities manifested in no worse than slight instability. CONCLUSIONS OF LAW 1. The criteria for service connection for obstructive sleep apnea have been met. 38 U.S.C. § 1110, 1131, 5107, 5110; 38 C.F.R. §§ 3.102, 3.310; VAOPGCPREC 1-2017 (January 6, 2017). 2. The criteria for an initial disability evaluation in excess of 10 percent prior to March 17, 2020 for right and left knee limitation of flexion have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5260. 3. For all times effective March 17, 2020 to the present, the criteria for the assignment of a 20 percent rating for right and left knee limitation of flexion, respectively, are met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5260. 4. For all times effective March 17, 2020 to the present, the criteria for the assignment of separate 10 percent ratings for right and left knee limitation of extension, respectively, are met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5261. 5. For all times effective September 7, 2018 to the present, the criteria for the assignment of separate 10 percent ratings for right and left knee instability, respectively, are met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5257. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served honorably in the United States Army from March 1994 to September 2000. These matters come before the Board of Veterans' Appeals (Board) on appeal from December 2015 (received by the Veteran in January 2016) and May 2021 rating decisions issued by the Department of Veterans Affairs (VA) Agency of Original Jurisdiction (AOJ). The Veteran testified before the Board at a March 2020 videoconference hearing. A transcript has been associated with the claims file. The Veteran's appeal was remanded for further development by the Board in July 2020. The appeal has been returned to the Board for additional appellate review. SERVICE CONNECTION SLEEP APNEA The Veteran contends that he has a current disability of obstructive sleep apnea, which has been caused or aggravated beyond its natural progression by PTSD, or, in the alternative, by obesity due to service-connected disabilities (to specifically include PTSD, bilateral knee disabilities, a lumbar spine disability, and right and left lower extremity radiculopathy). Secondary service connection may be established for a disability that is proximately due to, the result of, or aggravated by a service-connected disease or injury. 38 C.F.R. § 3.310(a); see also Allen v. Brown, 7 Vet. App. 439 (1995) (en banc). To substantiate a secondary service connection claim, the Veteran must show: (1) a present disability (for which service connection is sought); (2) a service-connected disability; and (3) competent evidence that the service connected disability caused or aggravated the disability for which service connection is sought. Although obesity, itself, is not considered a disability for VA purposes, when obesity has been caused by a service-connected condition, and subsequently causes another disability, obesity may be considered an "intermediate step" for establishing service connection on a secondary basis. See VAOPGCPREC 1-2017 (January 6, 2017). This inquiry extends both to causation and to aggravation. See Walsh v. Wilkie, No. 18-0495, 2020 U.S. App. Vet. Claims LEXIS 295 (Vet. App. Feb. 24, 2020). When there is an approximate balance of positive and negative evidence regarding the merits of an issue, the benefit of the doubt shall be given to the claimant. 38 U.S.C. § 5107 (b); 38 C.F.R. § 3.102. If the preponderance of the evidence is against the claim, the claim is to be denied. Gilbert v. Derwinski, 1 Vet. App. 49, 55 (1990). In its July 2020 remand, the Board requested medical opinions addressing the potential relationship between the Veteran's obstructive sleep apnea and obesity linked to service-connected disabilities, which include PTSD, bilateral knee disabilities, a lumbar spine disability, and right and left lower extremity radiculopathy. The evidence obtained and submitted by the Veteran is sufficient to establish such a relationship. See March 2021 VA Contract Examination Report: ("Based on the presenting evidence, the [V]eteran's obesity was at least as likely as not (50 percent probability) . . . caused by service-connected PTSD, lumbar spine disability, right and left lower extremity radiculopathy, and right and left knee disabilities."); ("Therefore, the current obstructive sleep apnea was at least as likely as not aggravated beyond its natural progression by obesity."). Additionally, an August 2020 private medical opinion from Dr. L.E.R. contained similarly findings, explaining how the Veteran's service-connected disabilities prevented him from exercising as he had done in the past, which led to weight gain, which, in turn, led to his obstructive sleep apnea. The Veteran and his attorney recently submitted a July 2021 letter from Dr. R. L., received by VA in September 2021. Dr. R.L. also opined that the Veteran's PTSD played a significant role in the Veteran's obesity, which in turn caused his sleep apnea. The Board finds these opinions highly probative. The Board acknowledges the May 2021 C&P addendum opinion from Dr. S.K.P. that was against the claim. Although the May 2021 C&P addendum opinion listed a number of risk factors for developing obesity (including family inheritance, genetics, lifestyle choices, alcohol intake, and eating and activity habits), Dr. S.K.P. did not explain how these risk factors bore upon the Veteran's development of obesity, in particular, which lessens its probative value. Based on the medical opinion evidence above, the Board finds that the evidence favors a finding that the Veteran's service-connected disabilities, to specifically include PTSD, caused or aggravated the Veteran's obesity, which in turn caused the Veteran's sleep apnea. On this theory of entitlement, the benefit sought on appeal is granted. INCREASED RATINGS RIGHT AND LEFT KNEE Disability evaluations are determined by the application of a schedule of ratings which is based, as far as can practically be determined, on the average impairment of earning capacity. 38 U.S.C. § 1155; 38 C.F.R. § 4.1. Each service-connected disability is rated on the basis of specific criteria identified by Diagnostic Codes. 38 C.F.R. § 4.27. When rating the Veteran's service-connected disability, the entire medical history must be borne in mind. Schafrath v. Derwinski, 1 Vet. App. 589 (1991). The Court has held that a claimant may experience multiple distinct degrees of disability that might result in different levels of compensation from the time the increased rating claim was filed until a final decision is made. Hart v. Mansfield, 21 Vet. App. 505 (2007). Separate evaluations may be assigned for separate periods of time if such distinct periods are shown by the competent evidence of record during the appeal, a practice known as staged ratings. See Fenderson v. West, 12 Vet. App. 119, 126 (1999). Regulations require that where there is a question as to which of two evaluations is to be applied, the higher evaluation will be assigned if the disability picture more nearly approximates the criteria required for that rating. Otherwise, the lower rating will be assigned. 38 C.F.R. § 4.7. Where there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, VA shall give the benefit of the doubt to the claimant. 38 U.S.C. § 5107 (b); 38 C.F.R. § 4.3; see also Gilbert v. Derwinski, 1 Vet. App. 49, 53 (1990). By way of background, the Veteran originally filed a claim for service connection for both knees in September 2014. The AOJ granted the Veteran's claims for right and left knee strains, inter alia, in a September 2015 rating decision, assigning noncompensable ratings for each knee, from September 2014. The Veteran timely disagreed with the initial ratings assigned in January 2016, on the grounds that his knee pain was more severe than assessed and was getting progressively worse. In February 2016, the Veteran requested that the Decision Review Officer (DRO) process be used to evaluate his claims for increased initial ratings for his right and left knee strains. In a June 2018 DRO rating decision, the AOJ increased the Veteran's initial ratings for his left and right knee strains to 10 percent. Following the July 2020 Board remand and associated development, in a May 2021 AOJ rating decision, the Veteran's right and left knee strain ratings were increased to 20 percent, effective October 9, 2020 through March 14, 2021; separate 10 percent ratings for right and left knee limited extension were also granted effective October 9, 2020 through March 14, 2021; thereafter, the ratings for the Veteran's right and left knee strains were reduced to 10 percent, and his ratings for right and left knee limited extension were also reduced to noncompensable, or 0 percent ratings. The assignment of a particular diagnostic code is "completely dependent on the facts of a particular case." Butts v. Brown, 5 Vet. App. 532, 538 (1993). One diagnostic code may be more appropriate than another based on such factors as an individual's relevant medical history, the current diagnosis, and demonstrated symptomatology. See Pernorio v. Derwinski, 2 Vet. App. 625, 629 (1992). VA Office of General Counsel has provided guidance concerning increased rating claims for knee disorders. Separate disability ratings may be assigned for distinct disabilities resulting from the same injury so long as the symptomatology for one condition was not "duplicative of or overlapping with the symptomatology" of the other condition. See Esteban v. Brown, 6 Vet. App. 259, 262 (1994). Here, the Board recognizes that under Lyles v. Shulkin, 29 Vet. App. 107 (2017), separate ratings may be warranted for limitation of motion, cartilage disability, and instability for the same knee, if supported by the facts. Normal range of motion of the knee is from 0 degrees of extension to 140 degrees of flexion. 38 C.F.R. § 4.71, Plate II. Diagnostic Code 5260, for limitation of leg flexion, provides for a noncompensable, or 0 percent rating, where flexion is limited to 60 degrees; a 10 percent rating, where flexion is limited to 45 degrees; a 20 percent rating, where flexion is limited to 30 degrees; and a 30 percent rating, where flexion is limited to 15 degrees. Diagnostic Code 5261, for limitation of leg extension, provides for a noncompensable, or 0 percent rating, where extension is limited to 5 degrees; a 10 percent rating, where extension is limited to 10 degrees; a 20 percent rating, where extension is limited to 15 degrees; a 30 percent rating, where extension is limited to 20 degrees; a 40 percent rating, where extension is limited to 30 degrees; and a 50 percent rating where extension is limited to 45 degrees. For disabilities evaluated on the basis of limitation of motion, VA is required to apply the provisions of Sections 4.40 and 4.45 pertaining to functional impairment. 38 C.F.R. §§ 4.40, 4.45. The Court has instructed that in ap plying these regulations, VA should obtain examinations in which the examiner determines whether the disability was manifested by weakened movement, excess fatigability, incoordination, or pain. Such inquiry is not to be limited to muscles or nerves. These determinations are, if feasible, to be expressed in terms of the degree of additional range-of-motion loss due to any weakened movement, excess fatigability, incoordination, flare-ups, or pain. See Mitchell v. Shinseki, 25 Vet. App. 32, 37 (2011); DeLuca v. Brown, 8 Vet. App. 202, 208 (1995). Diagnostic Code 5257 was recently amended, effective February 7, 2021. Schedule for Rating Disabilities: Musculoskeletal System and Muscle Injuries, 85 Fed. Reg. 76453, 76463 (Nov. 30, 2020) (codified at 38 C.F.R. § 4.71a, Diagnostic Code 5257). As the amendments became effective during the pendency of the Veteran's claim, the Board will consider the Veteran's claim under the old criteria prior to February 7, 2021, and both the old and new rating criteria from February 7, 2021, applying the criteria that is more favorable to the Veteran. In this regard, as of February 7, 2021, Diagnostic Code 5257 provides ratings for patellar instability and recurrent subluxation or lateral instability. For recurrent subluxation or lateral instability, a 10 percent rating is warranted for a sprain, incomplete ligament tear, or complete ligament tear (repaired, unrepaired, or failed repair) causing persistent instability, without a prescription from a medical provider for an assistance device (e.g., cane(s), crutch(es), walker) or bracing for ambulation. A 20 percent rating is assigned for one of the following: (a) sprain, incomplete ligament tear, or repaired complete ligament tear causing persistent instability, and a medical provider prescribes a brace and/or assistive device (e.g., cane(s), crutch(es), walker) for ambulation, or (b) unrepaired or failed repair of complete ligament tear causing persistent instability, and a medical provider prescribes either an assistive device (e.g., cane(s), crutch(es), walker) or bracing for ambulation. A 30 percent rating is warranted for unrepaired or failed repair of complete ligament tear causing persistent instability, and a medical provider prescribes both an assistive device (e.g., cane(s), crutch(es), walker) and bracing for ambulation. For recurrent patellar instability, a 20 percent disability rating is warranted for a diagnosed condition involving the patellofemoral complex with recurrent instability after surgical repair that requires a prescription by a medical provider for one of the following: a brace, cane, or walker. A 30 percent disability rating is warranted for a diagnosed condition involving the patellofemoral complex with recurrent instability after surgical repair that requires a prescription by a medical provider for a brace and either a cane or a walker. Under the prior version of Diagnostic Code 5257, for other impairment of the knee, a 10 percent rating is warranted for slight recurrent subluxation or lateral instability. A 20 percent rating is warranted for moderate recurrent subluxation or lateral instability. A 30 percent rating is warranted for severe recurrent subluxation or lateral instability. 38 C.F.R. § 4.71a, Diagnostic Code 5257. Notably, objective medical evidence is not required to establish lateral knee instability under DC 5257, so objective medical evidence cannot be categorically found more probative than lay evidence with respect to this Diagnostic Code. See English v. Wilkie, 30 Vet. App. 347, 352-53 (2018). The Board also notes the potential applicability of Diagnostic Code 5258, which provides for a 20 percent rating where there is cartilage, semilunar, dislocated, with frequent episodes of "locking," pain, and effusion into the joint. Such will be discussed in the analysis below. Evidentiary Review Right Knee In connection with his September 2014 initial claim for benefits, the Veteran's right knee was examined in April 2015. During his examination the Veteran reported experiencing intermittent pain since military service, including as a result of marching and doing other military exercises in the service. He reported taking glucosamine without full improvement, but did not report any other treatment. The Veteran exhibited 0 to 140 degrees of flexion and 0 degrees of extension, with no pain noted on exam, no evidence of pain with weight-bearing, no objective evidence of localized tenderness or pain on palpation of the joint or associated soft tissue, and no objective evidence of tenderness. The Veteran was able to perform repetitive use testing with at least three repetitions with no additional functional loss or range of motion loss after three repetitions. The Veteran was not being examined immediately after repetitive use over time; the examiner indicated that the examination was neither medically consistent or inconsistent with the Veteran's statements describing functional loss with repetitive use over time. The examiner also indicated that pain, weakness, fatigability or incoordination significantly limit functional ability with repeated use over a period of time. The examiner did not provide a response regarding flare-ups. The examiner indicated that the Veteran experienced no additional factors contributing to disability. Muscle strength testing was all normal, and the examiner indicated that the Veteran did not experience muscle atrophy. The examiner indicated the Veteran did not experience ankylosis. Joint stability testing was performed and was all normal. The examiner reported there was no history of recurrent subluxation, lateral instability, or recurrent effusion. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial and/or fibular impairment. The examiner indicated that the Veteran did not now have or has ever had a meniscus (semilunar cartilage) condition. The examiner indicated there were no other pertinent physical findings, complications, conditions, signs, symptoms or scars. The examiner also indicated that the Veteran did not use any assistive devices. Lastly, the examiner found that the Veteran's right knee condition did not impact his ability to perform any type of occupational task (such as standing, walking, lifting, sitting, etc.). The Veteran's right knee was next examined in May 2017. The examiner reported that in addition to a right knee strain, the Veteran also exhibited arthritis in his right knee. During the examination, the Veteran reported that he experienced flare-ups and that bad weather increased the pain, which lasted as long as the weather remained bad. The Veteran reported experiencing functional loss, insofar as he was not able to run, play basketball, bowl, or participate in any activity which included standing for long periods of time. The Veteran also reported that he struggled to sit for long periods of time (including, for example, on airplanes). The Veteran's initial range of motion for his right knee was 0 to 110 degrees of flexion and 110 to 0 degrees of extension. The examiner reported that the Veteran's range of motion, itself, contributed to a functional loss, insofar as the Veteran experienced difficulty performing movements requiring full range of motion of the knee. The examiner also indicated that the Veteran experienced pain with both flexion and extension, which resulted in a functional loss. The examiner indicated that the Veteran experienced pain with weight-bearing, and that there was objective evidence of crepitus. The examiner reported that the Veteran was able to perform repetitive use testing with at least three repetitions, with no additional functional loss or range of motion loss after three repetitions. However, the examiner also reported that the Veteran would experience functional loss with flare-ups and repeated use over time, on account of pain and lack of endurance. As expressed in terms of range of motion, the Veteran's range of motion with flare-ups and repetitive use over time would be 0 to 110 degrees of flexion and 110 to 0 degrees of extension. The examiner indicated that the Veteran experienced no additional factors contributing to disability. Muscle strength testing was all normal, and the examiner indicated that the Veteran did not experience muscle atrophy. The examiner indicated the Veteran did not experience ankylosis. Joint stability testing was performed and was all normal. The examiner reported there was no history of recurrent subluxation, lateral instability, or recurrent effusion. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial and/or fibular impairment. The examiner indicated that the Veteran did not now have or has ever had a meniscus (semilunar cartilage) condition. The examiner indicated there were no other pertinent physical findings, complications, conditions, signs, symptoms or scars. The examiner also indicated that the Veteran used a brace on his right knee (but not on his left) as an assistive device. The examiner also indicated that the Veteran experienced pain on passive range of motion testing, that the Veteran experienced pain when the joint was used in non-weight-bearing, and that the Veteran's opposing joint was not undamaged (i.e., the Veteran experienced bilateral conditions). Lastly, the examiner found that the Veteran's right knee condition resulted in a functional impact insofar as his disability limited him in sitting, standing, running, and walking for long periods of time. Following this examination, the Veteran testified at his March 2020 Board hearing that he experienced pain and instability (including two or three falls) in both of his knees. Thereafter and following remand in July 2020, the Veteran submitted a Disability Benefits Questionnaire (DBQ) from his private orthopedist, L.E.R., dated August 7, 2020, and a subsequent DBQ from his private physician, A.C., dated October 9, 2020. Turning first to the August 7, 2020 DBQ from L.E.R., the examiner indicated that the Veteran had diagnoses of knee joint arthritis and patellofemoral pain syndrome. The examiner reported that the Veteran experienced flare-ups, which he managed with Advil and glucosamine, and which caused him not to be able to exercise and resulted in weight gain and continued pain. The Veteran reported suffering a functional impairment on account of being unable to squat or kneel, and only being able to walk one to one-and-a-half miles. The Veteran's initial range of motion for his right knee was 95 degrees of flexion and 20 degrees of extension. The examiner reported that the Veteran was unable to perform repetitive use testing. The examiner indicated the Veteran experienced pain with active and passive range of motion testing, but that the pain did not contribute to functional loss or additional limitation of range of motion; however, the examiner also indicated that when used in weight-bearing or non-weight-bearing, the Veteran experienced pain which did result in functional loss. The examiner reported the Veteran experienced localized tenderness or pain to palpation of the joints or soft tissue (his prepatellar region was very tender to palpation above the area of his patellofemoral joint. The examiner indicated that contributing factors of disability included weakened movement, excess fatigability, incoordination (and impaired ability to execute skilled movements smoothly, pain on movement, swelling, deformity, instability of station, disturbance of locomotion, interference with sitting, and interference with standing. The examiner reported that these additional factors were associated with limitation of motion. The examiner also indicated that pain, weakness, fatigability, or incoordination could significantly limit functional ability during flare-ups or when the joint is used repeatedly over time, but also indicated that it was not feasible for her to estimate this limitation of motion in terms of range of motion. Additionally, the examiner indicated that the Veteran did not experience functional loss during flare-ups or when the joint is used repeatedly over a period of time or otherwise that was not associated with limitation of motion. The examiner indicated that the Veteran experienced a reduction in muscle strength due to his right knee diagnoses, which resulted in active movement against some resistance (4 out of 5) during flexion and extension. However, the examiner also indicated that the Veteran did not experience muscle atrophy. The examiner did not indicate whether the Veteran experienced ankylosis. The examiner also reported that the Veteran experienced a history of slight recurrent subluxation, and recurrent effusion from time to time, but did not have a history of lateral instability. Joint stability testing was performed, and the results were all normal. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial or fibular impairment. The examiner also reported that the Veteran experienced a leg length discrepancy (right leg 36 inches; left leg 37.5 inches). The examiner indicated that the Veteran had a meniscal condition in his right knee (meniscal tear), which had since healed. The examiner also indicated that the Veteran experienced Osgood Schlatter's disease in his right knee. The examiner indicated the Veteran used a brace constantly as an assistive device. The examiner noted that imaging results were available (February 2016 MRI), and that the imaging results showed a distal posterior cruciate ligament cyst, a healed medial meniscus tear, and a popliteal cyst in the Veteran's right knee. The examiner noted that the Veteran experienced a functional impact, insofar as he was unable to exercise, play basketball, go bowling, run, squat, jump, go up and down steps normally, extend his leg fully, and insofar as his leg locked up during sleep and as he experienced constant popping. The Veteran also submitted a private DBQ from A.C., dated October 9, 2020. The examiner noted that the Veteran's right knee condition has progressed over time, that the Veteran experienced flare-ups of severe pain, swelling, and loss of range of motion, which inhibit his mobility during flare-ups. The examiner reported that the Veteran's condition resulted in a functional impairment, as it limited his ability to climb stairs, drive long distances, and walk for more than 20 minutes at a time. The examiner also noted that, at times, the Veteran was unable to complete job tasks due to restricted range of motion. The Veteran's initial range of motion in his right knee was 85 degrees of flexion and 5 degrees of extension. The examiner indicated the Veteran was able to perform repetitive-use testing with three repetitions, but did not experience any additional limitation in range of motion after repetitive-use testing. The examiner indicated that the Veteran experienced pain on active, passive and/or repetitive use testing as well as in weight-bearing or non-weight-bearing and that this pain resulted in a functional loss. Additional contributing factors of disability included less movement than normal, weakened movement, excess fatigability, incoordination (impaired ability to execute skilled movements smoothly), pain on movement, swelling, instability of station, disturbance of locomotion, interference with sitting, and interference with standing. The examiner reported that during flare-ups or when the joint is used repeatedly over a period of time, the Veteran experienced functional loss and additional limitation of motion. She estimated the Veteran's range of motion in his right knee would decrease to 30 degrees of flexion and 10 degrees of extension during flare-ups or following repeated use over time. The examiner also indicated there were no contributing factors of disability, not associated with limitation of motion during flare-ups or when the joint is used repeatedly over a period of time or otherwise. The examiner indicated that the Veteran experienced a reduction in muscle strength due to his right knee diagnoses, which resulted in active movement against some resistance (4 out of 5) during flexion and extension. However, the examiner also indicated that the Veteran did not experience muscle atrophy and did not experience ankylosis. The examiner reported that the Veteran did not have a history of recurrent subluxation or lateral instability, but that the Veteran did have a history of recurrent effusion, which inhibited range of motion during flare-ups. Joint stability testing was performed, and the results were all normal. The examiner reported that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome, or any other tibial or fibular impairment. The examiner indicated that the Veteran had a bilateral meniscus injury (January 1995) with no current symptoms (and that the Veteran's current symptoms and limitation of motion were attributable to his service-connected knee condition). The examiner indicated that the Veteran regularly used bilateral knee strain braces as assistive devices. The examiner indicated the Veteran did not have any other pertinent physical findings, complications, conditions, signs or symptoms, or any scars related to his knee condition. Lastly, the examiner indicated the Veteran would experience a functional impact insofar as pain, swelling, and loss of range of motion prevented the Veteran from sitting, standing, and walking for prolonged periods of time, insofar as the Veteran experienced difficulty on account of swelling when using stairs, driving long distances, and insofar as the Veteran experienced limited mobility during flare-ups and reported locking and popping in his right knee. The Veteran was next examined in March 2021 by U.M., a VA contract examiner. The examiner noted that the Veteran was experiencing an increase in symptoms associated with his right knee disability, including increased dull pain, crepitus, locking, catching and stiffness. The examiner noted that his treatment included cortisone injections, Ibuprofen, ice/heat compresses, and a knee brace. The examiner noted that the Veteran experienced functional impairment in his work as a corrections officer on account of knee pain. The examiner noted that flare-ups of the Veteran's right knee occurred daily, were severe, lasted for three hours or more, were precipitated by prolonged standing, bending, walking, and squatting. His right knee flare-ups were alleviated by rest and medication. In regard to functional loss following repeated use over time, the Veteran remarked that standing for more than 30 minutes and walking two blocks or more aggravated his knee pain. The examiner indicated that the Veteran did not report or have a history of instability, recurrent subluxation, or frequent effusion of his knee. The Veteran's initial range of motion for his right knee was 120 degrees of flexion and 0 degrees of extension. The examiner reported that the Veteran experienced pain with flexion. The examiner reported there was evidence of pain with weight-bearing, active motion, and passive motion, and that the knee pain resulted in a functional limitation insofar as the Veteran experienced pain upon weight-bearing, prolonged walking, and squatting. The examiner reported there was objective evidence of crepitus, but no evidence of localized tenderness or pain on palpation of the joint or associated soft tissue. Following observed repetitive use with at least three repetitions, the Veteran experienced additional loss of function and range of motion. The Veteran's range of motion decreased to 100 degrees of flexion and 0 degrees of extension. The examiner indicated that the Veteran would experience additional functional loss on account of increased pain and fatigability. The examiner indicated that, although the Veteran was not being examined immediately following repeated use over time or during a flare-up, the procured evidence (statements from the Veteran) suggested pain and fatigability resulted in a functional loss. The examiner estimated that the Veteran's range of motion in his right knee decreased to 100 degrees of flexion and 0 degrees of extension. The examiner indicated there were no additional contributing factors of disability. The examiner indicated the Veteran was not experiencing muscular atrophy and did not have ankylosis. Joint stability testing was all normal. The examiner indicated there was no recurrent subluxation, persistent instability, or recurrent patellar instability. The examiner indicated that there has not been a ligament tear. The examiner indicated that the Veteran did not require a prescription (by a medical provider) for a cane, walker, crutches, or a brace. The examiner indicated that the Veteran did not experience tibial or fibular impairment, and had not been diagnosed with a meniscus (semilunar cartilage) condition or undergone surgical procedures, and did not have other pertinent physical findings, complications, conditions, signs, symptoms, and scars related to his condition. Concerning a functional impact, the examiner indicated that the Veteran would experience difficulty with kneeling, bending, standing for more than an hour, walking for more than a mile at a time, and ascending/descending stairs. In additional remarks, the examiner noted there were no findings of joint instability of the right knee, nor were there findings of chronic exertional compartment syndrome of the right lower extremity. The Veteran's March 2016 private treatment records, from the aforementioned examiner, L.E.R., show a diagnosis of chondromalacia patella in the Veteran's right knee, with flexion of 110 degrees and extension of 0 degrees. April 2017 private treatment records, also from L.E.R., show flexion of 100 degrees and extension of 5 degrees on the right, as well as a recommendation for a patellofemoral knee brace for the Veteran's right knee. Left Knee In connection with his September 2014 initial claim for benefits, the Veteran's left knee was examined in April 2015. During his examination the Veteran reported experiencing intermittent pain since military service, including as a result of marching and doing other military exercises in the service. He reported taking glucosamine without full improvement, but did not report any other treatment. The Veteran exhibited 0 to 140 degrees of flexion and 0 degrees of extension, with no pain noted on exam, no evidence of pain with weight-bearing, no objective evidence of localized tenderness or pain on palpation of the joint or associated soft tissue, and no objective evidence of tenderness. The Veteran was able to perform repetitive use testing with at least three repetitions with no additional functional loss or range of motion loss after three repetitions. The Veteran was not being examined immediately after repetitive use over time; the examiner indicated that the examination was neither medically consistent or inconsistent with the Veteran's statements describing functional loss with repetitive use over time. The examiner also indicated that pain, weakness, fatigability or incoordination significantly limit functional ability with repeated use over a period of time. The examiner did not provide a response regarding flare-ups. The examiner indicated that the Veteran experienced no additional factors contributing to disability. Muscle strength testing was all normal, and the examiner indicated that the Veteran did not experience muscle atrophy. The examiner indicated the Veteran did not experience ankylosis. Joint stability testing was performed and was all normal. The examiner reported there was no history of recurrent subluxation, lateral instability, or recurrent effusion. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial and/or fibular impairment. The examiner indicated that the Veteran did not now have or has ever had a meniscus (semilunar cartilage) condition. The examiner indicated there were no other pertinent physical findings, complications, conditions, signs, symptoms or scars. The examiner also indicated that the Veteran did not use any assistive devices. Lastly, the examiner found that the Veteran's left knee condition did not impact his ability to perform any type of occupational task (such as standing, walking, lifting, sitting, etc.). The Veteran's left knee was next examined in May 2017. The examiner reported that in addition to a left knee strain, the Veteran also exhibited arthritis in his left knee. During the examination, the Veteran reported that he experienced flare-ups and that bad weather increased the pain, which lasted as long as the weather was bad. The Veteran reported experiencing functional loss, insofar as he was not able to run, play basketball, bowl, or participate in any activity which included standing for long periods of time. The Veteran also reported that he struggled to sit for long periods of time (including, for example, on airplanes). The Veteran's initial range of motion for his left knee was 0 to 110 degrees of flexion and 110 to 0 degrees of extension. The examiner reported that the Veteran's range of motion, itself, contributed to a functional loss, insofar as the Veteran experienced difficulty performing movements requiring full range of motion of the knee. The examiner also indicated that the Veteran experienced pain with both flexion and extension, which resulted in a functional loss. The examiner indicated that the Veteran experienced pain with weight-bearing, and that there was objective evidence of crepitus. The examiner reported that the Veteran was able to perform repetitive use testing with at least three repetitions, with no additional functional loss or range of motion loss after three repetitions. However, the examiner also reported that the Veteran would experience functional loss with flare-ups and repeated use over time, on account of pain and lack of endurance. As expressed in terms of range of motion, the Veteran's range of motion with flare-ups and repetitive use over time would be 0 to 110 degrees of flexion and 110 to 0 degrees of extension. The examiner indicated that the Veteran experienced no additional factors contributing to disability. Muscle strength testing was all normal, and the examiner indicated that the Veteran did not experience muscle atrophy. The examiner indicated the Veteran did not experience ankylosis. Joint stability testing was performed and was all normal. The examiner reported there was no history of recurrent subluxation, lateral instability, or recurrent effusion. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial and/or fibular impairment. The examiner indicated that the Veteran did not now have or has ever had a meniscus (semilunar cartilage) condition. The examiner indicated there were no other pertinent physical findings, complications, conditions, signs, symptoms or scars. The examiner also indicated that the Veteran used a brace on his right knee (but not on his left) as an assistive device. The examiner also indicated that the Veteran experienced pain on passive range of motion testing, that the Veteran experienced pain when the joint was used in non-weight-bearing, and that the Veteran's opposing joint was not undamaged (i.e., the Veteran experienced bilateral conditions). Lastly, the examiner found that the Veteran's left knee condition resulted in a functional impact insofar as his disability limited him in sitting, standing, running, and walking for long periods of time. The Board again notes that following this examination, the Veteran testified at his March 2020 Board hearing that he experienced pain and instability (including two or three falls) in both of his knees. Thereafter and following remand in July 2020, the Veteran submitted a Disability Benefits Questionnaire (DBQ) from his private orthopedist, L.E.R., dated August 7, 2020, and a subsequent DBQ from his private physician, A.C., dated October 9, 2020. Turning first to the August 7, 2020 DBQ from L.E.R., the examiner indicated that the Veteran had diagnoses of knee joint arthritis and patellofemoral pain syndrome. The examiner reported that the Veteran experienced flare-ups, which he managed with Advil and glucosamine, and which caused him not to be able to exercise and resulted in weight gain and continued pain. The Veteran reported suffering a functional impairment on account of being unable to squat or kneel, and only being able to walk one to one-and-a-half miles. The Veteran's initial range of motion for his left knee was 90 degrees of flexion and 20 degrees of extension. The examiner reported that the Veteran was unable to perform repetitive use testing. The examiner indicated the Veteran experienced pain with active and passive range of motion testing, but that the pain did not contribute to functional loss or additional limitation of range of motion; however, the examiner also indicated that when used in weight-bearing or non-weight-bearing, the Veteran experienced pain which did result in functional loss. The examiner reported the Veteran experienced localized tenderness or pain to palpation of the joints or soft tissue (his prepatellar region was very tender to palpation above the area of his patellofemoral joint. The examiner indicated that contributing factors of disability included weakened movement, excess fatigability, incoordination (and impaired ability to execute skilled movements smoothly, pain on movement, swelling, instability of station, disturbance of locomotion, interference with sitting, and interference with standing. The examiner reported that these additional factors were associated with limitation of motion. The examiner also indicated that pain, weakness, fatigability, or incoordination could significantly limit functional ability during flare-ups or when the joint is used repeatedly over time, but also indicated that it was not feasible for her to estimate this limitation of motion in terms of range of motion. Additionally, the examiner indicated that the Veteran did not experience functional loss during flare-ups or when the joint is used repeatedly over a period of time or otherwise that was not associated with limitation of motion. The examiner indicated that the Veteran experienced a reduction in muscle strength due to his left knee diagnoses, which resulted in active movement against some resistance (4 out of 5) during flexion and extension. However, the examiner also indicated that the Veteran did not experience muscle atrophy. The examiner did not indicate whether the Veteran experienced ankylosis. The examiner also reported that the Veteran experienced a history of slight recurrent subluxation, and recurrent effusion from time to time, but did not have a history of lateral instability. Joint stability testing was performed, and the results were all normal. The examiner indicated that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome or any other tibial or fibular impairment. The examiner also reported that the Veteran experienced a leg length discrepancy (right leg 36 inches; left leg 37.5 inches). The examiner indicated that the Veteran did not have a meniscal condition in his left knee. The examiner indicated the Veteran used a brace constantly as an assistive device. The examiner noted that imaging results were available (February 2016 MRI), and that the imaging results showed a ganglial cyst in the medial meniscus root of the Veteran's left knee. The examiner noted that the Veteran experienced a functional impact, insofar as he was unable to exercise, play basketball, go bowling, run, squat, jump, go up and down steps normally, extend his leg fully, and insofar as his leg locked up during sleep and as he experienced constant popping. The Veteran also submitted a private DBQ from A.C., dated October 9, 2020. The examiner noted that the Veteran's left knee condition has progressed over time, that the Veteran experienced flare-ups of severe pain, swelling, and loss of range of motion, which inhibit his mobility during flare-ups. The examiner reported that the Veteran's condition resulted in a functional impairment, as it limited his ability to climb stairs, drive long distances, and walk for more than 20 minutes at a time. The examiner also noted that, at times, the Veteran was unable to complete job tasks due to restricted range of motion. The Veteran's initial range of motion in his left knee was 85 degrees of flexion and 5 degrees of extension. The examiner indicated the Veteran was able to perform repetitive-use testing with three repetitions, but did not experience any additional limitation in range of motion after repetitive-use testing. The examiner indicated that the Veteran experienced pain on active, passive and/or repetitive use testing as well as in weight-bearing or non-weight-bearing and that this pain resulted in a functional loss. Additional contributing factors of disability included less movement than normal, weakened movement, excess fatigability, incoordination (impaired ability to execute skilled movements smoothly), pain on movement, swelling, instability of station, disturbance of locomotion, interference with sitting, and interference with standing. The examiner reported that during flare-ups or when the joint is used repeatedly over a period of time, the Veteran experienced functional loss and additional limitation of motion. She estimated the Veteran's range of motion in his left knee would decrease to 30 degrees of flexion and 10 degrees of extension during flare-ups or following repeated use over time. The examiner also indicated there were no contributing factors of disability, not associated with limitation of motion during flare-ups or when the joint is used repeatedly over a period of time or otherwise. The examiner indicated that the Veteran experienced a reduction in muscle strength due to his left knee diagnoses, which resulted in active movement against some resistance (4 out of 5) during flexion and extension. However, the examiner also indicated that the Veteran did not experience muscle atrophy and did not experience ankylosis. The examiner reported that the Veteran did not have a history of recurrent subluxation or lateral instability, but that the Veteran did have a history of recurrent effusion, which inhibited range of motion during flare-ups. Joint stability testing was performed, and the results were all normal. The examiner reported that the Veteran did not now have or has ever had recurrent patellar dislocation, "shin splints" (medial tibial stress syndrome), stress fractures, chronic exertional compartment syndrome, or any other tibial or fibular impairment. The examiner indicated that the Veteran had a bilateral meniscus injury (January 1995) with no current symptoms (and that the Veteran's current symptoms and limitation of motion were attributable to his service-connected knee condition). The examiner indicated that the Veteran regularly used bilateral knee strain braces as assistive devices. The examiner indicated the Veteran did not have any other pertinent physical findings, complications, conditions, signs or symptoms, or any scars related to his knee condition. Lastly, the examiner indicated the Veteran would experience a functional impact insofar as pain, swelling, and loss of range of motion prevented the Veteran from sitting, standing, and walking for prolonged periods of time, insofar as the Veteran experienced difficulty on account of swelling when using stairs, driving long distances, and insofar as the Veteran experienced limited mobility during flare-ups and reported locking and popping in his left knee. The Veteran was next examined in March 2021 by U.M., a VA contract examiner. The examiner noted that the Veteran was experiencing an increase in symptoms associated with his left knee disability, including increased dull pain, crepitus, locking, catching and stiffness. The examiner noted that his treatment included cortisone injections, Ibuprofen, ice/heat compresses, and a knee brace. The examiner noted that the Veteran experienced functional impairment in his work as a corrections officer on account of knee pain. The examiner noted that flare-ups of the Veteran's left knee occurred daily, were severe, lasted for three hours or more, are precipitated by prolonged standing, bending, walking, and squatting. His left knee flare-ups were alleviated by rest and medication. In regard to functional loss following repeated use over time, the Veteran remarked that standing for more than 30 minutes and walking two blocks or more aggravated his knee pain. The examiner indicated that the Veteran did not report or have a history of instability, recurrent subluxation, or frequent effusion of his knee. The Veteran's initial range of motion for his left knee was 120 degrees of flexion and 0 degrees of extension. The examiner reported that the Veteran experienced pain with flexion. The examiner reported there was evidence of pain with weight-bearing, active motion, and passive motion, and that the knee pain resulted in a functional limitation insofar as the Veteran experienced pain upon weight-bearing, prolonged walking, and squatting. The examiner reported there was objective evidence of crepitus, but no evidence of localized tenderness or pain on palpation of the joint or associated soft tissue. Following observed repetitive use with at least three repetitions, the Veteran experienced additional loss of function and range of motion. The Veteran's range of motion for his left knee decreased to 110 degrees of flexion and 0 degrees of extension. The examiner indicated that the Veteran would experience additional functional loss on account of increased pain and fatigability. The examiner indicated that, although the Veteran was not being examined immediately following repeated use over time or during a flare-up, the procured evidence (statements from the Veteran) suggested pain and fatigability resulted in a functional loss. The examiner estimated that the Veteran's range of motion in his left knee decreased to 110 degrees of flexion and 0 degrees of extension. The examiner indicated there were no additional contributing factors of disability. The examiner indicated the Veteran was not experiencing muscular atrophy and did not have ankylosis. Joint stability testing was all normal. The examiner indicated there was no recurrent subluxation, persistent instability, or recurrent patellar instability. The examiner indicated that there has not been a ligament tear. The examiner indicated that the Veteran did not require a prescription (by a medical provider) for a cane, walker, crutches, or a brace. The examiner indicated that the Veteran did not experience tibial or fibular impairment, and had not been diagnosed with a meniscus (semilunar cartilage) condition or undergone surgical procedures, and did not have other pertinent physical findings, complications, conditions, signs, symptoms, and scars related to his condition. Concerning a functional impact, the examiner indicated that the Veteran would experience difficulty with kneeling, bending, standing for more than an hour, walking for more than a mile at a time, and ascending/descending stairs. In additional remarks, the examiner noted there were no findings of joint instability of the left knee, nor were there findings of chronic exertional compartment syndrome of the left lower extremity. The Veteran's March 2016 private treatment records, from the aforementioned examiner, L.E.R., show a diagnosis of chondromalacia patella in the Veteran's left knee, with flexion of 120 degrees and extension of -5 degrees. April 2017 private treatment records, also from L.E.R., show flexion of 115 degrees and extension of 0 degrees on the left. Analysis Limitation of Flexion a. Prior to March 17, 2020 For all times prior to March 17, 2020, which is the date of the Veteran's Board hearing, the evidence of record is against a finding that a rating higher than the currently assigned 10 percent is warranted for limitation of flexion under Diagnostic Code 5260, for each knee respectively. As discussed above, the Veteran's knee disabilities, although painful, did not manifest in limitation of flexion to a compensable degree on any range of motion test administered prior to March 17, 2020. While the Veteran did describe having experienced flare-ups during this time period, the May 2017 VA examiner provided estimates as to the impact of flare-ups and repetitive use had on limitation of flexion, noting that such would only limit flexion to 110 degrees. Considering all Deluca factors, the Board finds no basis to assign a rating higher than 10 percent under Diagnostic Code 5260 prior to March 17, 2020, as such would require limitation of flexion to at least 30 degrees. Indeed, during flare-ups, which is presumably when the Veteran's disability is at its worst severity, the Veteran was able to flex to 110 degrees. For these reasons, entitlement to an initial rating greater than 10 percent for both the Veteran's right and the left knee prior to March 17, 2020 is denied. b. From March 17, 2020 to the present As discussed above, on March 17, 2020, the Veteran testified before the Board and credibly reported observing worsened knee severity. Based on this testimony, the Board remanded the Veteran's claims for higher ratings for additional development. The Veteran submitted a private DBQ dated August 7, 2020 noting limitation of flexion of the right knee to 95 degrees, and the left to 90 degrees. Although flare-ups were reported and the examiner, L.E.R., indicated that such would significantly limit functional ability, L.E.R. did not provide an estimate as to whether flare-ups or repeated use would negatively impact limitation of motion. Importantly, as noted above, the Veteran submitted another DBQ in October 2020 from A.C., who did in fact provide estimates of range of motion loss during flare-ups or after repetitive use. Indeed, A.C. estimated that flare-ups would cause limitation of flexion to 30 degrees in both knees. Such limitation warrants the assignment of a 20 percent rating under Diagnostic Code 5260. The AOJ recognized as much, and assigned an increased rating to 20 percent effective October 9, 2020, which is the date of the DBQ completed by A.C. Given that the Veteran credibly described worsened symptomatology at his March 17, 2020 hearing, and that the August 2020 DBQ did not include estimates as to range of motion loss during flare-ups or after repetitive use, the Board will resolve all doubt in the Veteran's favor and presume that the levels of severity described by A.C. in October 2020 were in indicative of the severity level throughout the period from the date of his Board hearing. Accordingly, an increased rating to 20 percent for both left and right knee limitation of flexion is granted under Diagnostic Code 5260, effective March 17, 2020. As noted above, the AOJ decreased the Veteran's right and left knee flexion ratings to 10 percent respectively, effective March 15, 2021 based on the range of motion findings of the March 2021 examiner. The Board has reviewed the most recent examination and while objective range of motion testing revealed limitation of flexion 120 degrees for both knees, the examiner estimated only a 20 degree range of motion loss during flare-ups and after repetitive use for the right knee, and only a 10 degree range of motion loss for the left. Elsewhere in the report, the examiner characterized the Veteran's flare-ups as "severe" and occurring daily, lasting several hours. The examiner did not reconcile these estimates, which represent modest loss of motion, with the October 2020 estimates of A.C., which suggested significantly worse limitation. Given this discrepancy and ambiguity, the Board will resolve all doubt in the Veteran's favor and continue the 20 percent rating for each knee through to the present day. In other words, a rating of 20 percent based on limitation of flexion under Diagnostic Code 5260 is granted for both the right and left knee, effective for all times since his Board hearing, to include after March 15, 2021. In sum, the appeal for ratings higher than the currently assigned 10 percent for limitation of flexion of the right or left knee prior to March 17, 2020 is denied. Increased ratings to 20 percent are granted under Diagnostic Code 5260 for each knee based on limitation of flexion for all times where a 20 percent rating is not already in effect, beginning March 17, 2020 to the present. Limitation of Extension a. Prior to March 17, 2020 For all times prior to March 17, 2020, which is the date of the Veteran's Board hearing, the evidence of record is against a finding that separate compensable rating is warranted for limitation of extension under Diagnostic Code 5261, for either knee. As discussed above, the Veteran's knee disabilities did not manifest in limitation of extension to a compensable degree on any range of motion test administered prior to March 17, 2020. While the Veteran did describe having experienced flare-ups during this time period, the May 2017 VA examiner provided estimates as to the impact of flare-ups and repetitive use had on limitation of flexion, noting that such would not limit extension for either knee. Private treatment reports during this time period reflect limitation of extension to, at worst, 5 degrees. See March 2016 and April 2017 assessments. Considering all Deluca factors, the Board finds no basis to assign a separate compensable rating under Diagnostic Code 5261 for limitation of extension of either knee prior to March 17, 2020, as such would require limitation of extension to at least 10 degrees. Indeed, during flare-ups, which is presumably when the Veteran's disability is at its worst severity, the Veteran was estimated to be able to fully extend both knees. For these reasons, entitlement to a separate compensable rating for limitation of extension under Diagnostic Code 5261 for either the Veteran's right and the left knee prior to March 17, 2020 is denied. The Board notes in passing that during the time period prior to March 17, 2020, the Veteran's 10 percent rating for each knee was based on painful motion under the provisions of 38 C.F.R. § 4.59. This regulation allows for the assignment of a single compensable percent rating for the joint, and does not authorize two separate compensable ratings for painful flexion and extension. b. From March 17, 2020 to the present As discussed above, on March 17, 2020, the Veteran testified before the Board and credibly observed worsened knee severity. Based on this testimony, the Board remanded the Veteran's claims for higher ratings for additional development. The Veteran submitted a private DBQ dated August 7, 2020 noting limitation of extension of the right knee to 20 degrees, and the left to 20 degrees. Although flare-ups were reported and the examiner, L.E.R., indicated that such would significantly limit functional ability, L.E.R. did not provide an estimate as to whether flare-ups or repeated use would negatively impact limitation of motion. Importantly, as noted above, the Veteran submitted another DBQ in October 2020 from A.C. At that examination, limitation of extension was only to 5 degrees for each knee. A.C. estimated that flare-ups would cause limitation of extension to 10 degrees in both knees. At the March 2021 examination, no limitation of extension was shown for either knee on actual testing, and the examiner estimated no additional loss of extension after repetitive use or during flare-ups. As discussed above, the Board is not entirely satisfied with the flare-ups estimates provided by the March 2021 examiner, as the examiner failed to acknowledge worse findings and estimates made by L.E.R. and A.C. within the year prior. That stated, the limitation of extension identified by L.E.R. in August 2020 to 20 degrees (without considering flare-ups) appears to be a medical outlier. Indeed, on actual testing, the Veteran's limitation of extension in either knee has never been measured as limited to more than 5 degrees, both before the August 2020 examination and after. After reviewing all the evidence, to include the Veteran's lay statements, the Board finds that the currently assigned 10 percent rating for limitation of extension of each knee should be made effective March 17, 2020 and should extend to the present day, to include all times after March 15, 2021. The limitations identified upon examination in October 2020 by A.C. appear most consistent with the record, and also reflect a degree of disability warranting a compensable rating. As the Veteran reported worsened symptoms at his March 2020 hearing, the Board will resolve all doubt in his favor and make the separate ratings for each knee effective that date. In sum, separate 10 percent ratings based on limitation of extension of each knee, under Diagnostic Code 5261 are granted, effective March 17, 2020, but no earlier. These rating are assigned for all times where a 10 percent rating based on extension is not already in effect, to include after March 15, 2021. Instability Regarding subluxation and instability, the August 2020 examination indicated the Veteran had a history of recurrent subluxation. The Veteran also testified during his March 2020 Board hearing that he had fallen two or three times on account of knee instability. He does wear knee braces for support. Notably, the Veteran filed a claim specifically for right and left knee instability in September 2018. See September 2018 Veteran's Supplemental Claim for Compensation. Aside from the above, all other medical examination reports of record dated throughout the appeal indicate that the Veteran presented with no subluxation or instability. Thus, in considering the Veteran's competent lay descriptions of experiencing some falling, as well as the fact that on one occasion, in August 2020, he was noted to have subluxation, coupled with the pertinently normal assessments throughout the appeal period otherwise, the Board will resolve all doubt in the Veteran's favor and award a 10 percent rating for each knee for instability that is "slight" under the former diagnostic criteria. See English v. Wilkie, 30 Vet. App. 347, 349 (2018) ("nothing in [DC] 5257 provides that objective medical evidence is required or is to be favored over lay evidence"). These separate awards are effective September 7, 2018, which is the first date it was factually ascertainable (by dint of the Veteran's instability claim) that the Veteran experienced right and left knee instability. Although the new criteria for rating musculoskeletal disabilities became effective February 7, 2021, the Board emphasizes that employing the former criteria for knee instability is more favorable to the Veteran, as persistent instability is not shown. In sum, separate 10 percent ratings based on right and left knee instability, respectively, are granted, effective September 7, 2018. Other Considerations Additionally, the Board has considered whether higher or separate ratings are warranted under alternate diagnostic codes. However, there is no indication of ankylosis, removal or dislocation of semilunar cartilage, tibia and fibula impairment, or genu recurvatum. As such, ratings under Diagnostic Codes 5256, 5258, 5259, 5262, and 5263 are precluded. The Board acknowledges that the August 2020 examiner indicated the Veteran had a meniscal condition in his right knee (a healed right medial meniscus tear). However, there is no evidence that the Veteran suffers from a current disability of his meniscus or semilunar cartilage. Moreover, although there is a reported history of occasional locking and effusion, a separate rating under Diagnostic Code 5258 would amount to impermissible pyramiding. Indeed, Diagnostic Code 5258 allows for a 20 percent rating for dislocated semilunar cartilage with frequent episodes of locking, pain, and effusion into the joint. As discussed above, the Veteran's right and left knee pain symptomatology is already contemplated in the current 10 percent ratings in effect prior to March 17, 2020 (based on the presence of painful motion), and after March 17, 2020 (based on increased ratings granted pursuant to Deluca factors, to specifically include an increase from 10 to 20 percent based on limited flexion during painful flare-ups, and the award of a separate 10 percent rating for limited extension during painful flare-ups). Given that the rating criteria under 5258 are conjunctivemeaning that frequent locking, pain and effusion must be present to warrant the assignment of the 20 percent ratingthe award of a separate rating under Diagnostic Code 5258 would effectively compensate the Veteran's pain symptoms twice, resulting in impermissible pyramiding. As the Veteran did not undergo removal of semilunar cartilage, separate ratings under Diagnostic Code 5259 are also not warranted. Finally, the Board observes that the Veteran is currently working as a corrections officer. Thus, entitlement to a total disability rating based on individual unemployability (TDIU) has not been raised. See March 2021 C&P Examination Report. Conclusion In conclusion, the appeal for ratings higher than the currently assigned 10 percent for limitation of flexion of the right or left knee prior to March 17, 2020 is denied. Increased ratings to 20 percent are granted under Diagnostic Code 5260 for each knee based on limitation of flexion for all times where a 20 percent rating is not already in effect, beginning March 17, 2020 to the present. Separate 10 percent ratings based on limitation of extension of each knee, under Diagnostic Code 5261 are granted, effective March 17, 2020, but no earlier. These rating are assigned for all times where a 10 percent rating based on extension is not already in effect, to include after March 15, 2021. Separate 10 percent ratings based on right and left knee instability, respectively, are granted, effective September 7, 2018. V. Chiappetta Veterans Law Judge Board of Veterans' Appeals Attorney for the Board A. Hennessy, Associate Counsel The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.