Citation Nr: 22012008 Decision Date: 03/02/22 Archive Date: 03/02/22 DOCKET NO. 17-08 720 DATE: March 2, 2022 ORDER An initial rating higher than 10 percent for left knee arthritis based on limitation of flexion prior to October 17, 2016 is denied. A separate initial rating of 10 percent for left knee arthritis based on limitation of extension effective July 9, 2013 through July 13, 2014 is granted. A separate initial rating of 30 percent for left knee arthritis based on limitation of extension effective July 14, 2014 through October 16, 2016 is granted An initial rating higher than 10 percent for left knee instability prior to October 17, 2016 is denied. A rating higher than 30 percent for residuals of a total left knee replacement from December 1, 2017 forward is denied. FINDINGS OF FACT 1. Prior to October 17, 2016, the Veteran's left knee arthritis was manifested by limitation in range of flexion, which was still in excess of 60 degrees. 2. From July 9, 2013 through July 13, 2014, the Veteran's left knee arthritis was manifested by limitation of extension to 10 degrees. 3. From July 14, 2014 through October 16, 2016, the Veteran's left knee arthritis was manifested by limitation of extension to 25 degrees. 4. Prior to October 17, 2016, the Veteran had no more than slight instability of the left knee. 5. Since December 1, 2017, the residuals of the Veteran's total left knee replacement have not been manifested by severe painful motion or weakness; her left knee range of extension has been normal without pain, and left knee range of flexion in excess of 60 degrees; her left knee strength has been normal. CONCLUSIONS OF LAW 1. Prior to October 17, 2016, the criteria for a rating higher than 10 percent for left knee arthritis based on limitation of flexion have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 3.321, 4.3, 4.71a, Diagnostic Codes 5003, 5260. 2. From July 9, 2013 through July 13, 2014, the criteria for a separate 10 percent rating for left knee arthritis based on limitation of extension have been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 3.321, 4.3, 4.71a, Diagnostic Codes 5003, 5261. 3. From July 14, 2014 through October 16, 2016, the criteria for a separate 30 percent rating for left knee arthritis based on limitation of extension have been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 3.321, 4.3, 4.71a, Diagnostic Codes 5003, 5261. 4. Prior to October 17, 2016, the criteria for a rating higher than 10 percent for left knee instability have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 3.321, 4.3, 4.71a, Diagnostic Code 5257. 5. Since December 1, 2017, the criteria for a rating higher than 30 percent for residuals of a total left knee replacement have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.102, 3.321, 4.3, 4.71a, Diagnostic Codes 5055, 5260, 5261. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served honorably on active duty in the U.S. Air Force from February 1983 to January 1990, from May 1999 to September 1999, from November 2001 to June 2002, from April 2003 to March 2005, from December 2008 to March 2009, and from August 2011 to April 2012. She also had additional periods of inactive duty for training (INACDUTRA) and active duty for training (ACDUTRA). This matter comes before the Board of Veterans' Appeals (Board) on appeal from a May 2014 rating decision of a Department of Veterans Affairs (VA) Regional Office (RO). The Board remanded the matter in January 2020 and July 2021 for further development. The Veteran testified at a hearing before the undersigned Veterans Law Judge in August 2019. A transcript of the hearing is of record. Increased Rating VA has adopted a Schedule for Rating Disabilities to evaluate service-connected disabilities. 38 U.S.C. § 1155; 38 C.F.R. § 3.321; see generally, 38 C.F.R. § Part IV. The basis of disability evaluations is the ability of the body as a whole, or of the psyche, or of a system or organ of the body to function under the ordinary conditions of daily life, including employment. 38 C.F.R. § 4.10. The percentage ratings in the Schedule for Rating Disabilities represent, as far as practicably can be determined, the average impairment in earning capacity resulting from service-connected disabilities in civilian occupations. 38 U.S.C. § 1155; 38 C.F.R. § 4.1. Generally, the degrees of disability specified are considered adequate to compensate for considerable loss of working time from exacerbation or illness proportionate to the severity of the several grades of disability. 38 C.F.R. § 4.1. Diagnostic codes in the rating schedule identify the various disabilities and the criteria for specific ratings. If two disability evaluations are potentially applicable, the higher evaluation will be assigned if the disability picture more nearly approximates the criteria required for that rating. 38 C.F.R. § 4.7. Otherwise, the lower rating will be assigned. Id. All reasonable doubt regarding the degree of disability will be resolved in favor of the claimant. 38 C.F.R. § 4.3. Because the level of disability may have varied over the course of the claim, the rating may be "staged" higher or lower for segments of time during the period under review in accordance with such variations. Hart v. Mansfield, 21 Vet. App. 505, 509-10 (2007); Fenderson v. West, 12 Vet. App. 119, 126 (1999). A claimant is entitled to the benefit of the doubt when there is an approximate balance of positive and negative evidence on any issue material to the claim. 38 U.S.C. § 5107; 38 C.F.R. § 3.102. If the positive and negative evidence is in approximate balance (which includes but is not limited to equipoise), the claimant receives the benefit of the doubt. Lynch v. McDonough, No. 2020-2067, 2021 U.S. App. LEXIS 37307 at *10 (Fed. Cir. Dec. 7, 2021). If the evidence persuasively favors one side or the other, there is not an approximate balance, and therefore the benefit-of-the-rule does not apply. Id. at *11. Factual Background The period at issue begins July 9, 2013, the effective date of service connection for the Veteran's left knee disability. However, the Board will begin with earlier records documenting the recent history of her left knee disability prior to that period, as they provide essential information bearing on its nature and severity. An April 2012 service treatment record reflects that the Veteran had left knee pain and a sense of instability. It was noted that she had undergone a ligament repair in 1980. An April 2012 x-ray study showed no fracture of subluxation. Moderate tricompartment degenerative changes were seen. There was no significant joint effusion. The impression was moderate degenerative joint disease. An April 2012 magnetic resonance imaging (MRI) study showed a subacute to remote complete tear of the anterior cruciate ligament (ACL) tear and moderate to severe tricompartmental osteoarthritis. In August 2012, the Veteran underwent left knee arthroscopic surgery at a private facility consisting of ACL reconstruction, a partial medial and lateral meniscectomy, chondroplasty of the patella, trochlea, and medial femoral condyle, removal of a spur from the inferior pole patella, and removal of a foreign body suture that had been retained. The postoperative diagnosis was an ACL tear, a tear of the medial and lateral meniscus, chondromalacia, an arthritic spur, and retained foreign bodies. In November 2012, a second arthroscopic surgical procedure was performed at a private facility consisting of debridement and manipulation of the left knee. The Veteran was then seen for post-surgical follow-up periodically throughout 2013. Private treatment records show that in June 2013, she reported still having some left knee pain, stiffness, and soreness. On examination, her left knee flexion was to 115/120 degrees. She lacked about 8 to 10 degrees extension of the knee. An October 2013 record notes that she had no swelling or buckling of the knee. However, it was tight and stiff. She struggled with obtaining full extension through walking and exercise. On examination, there was no effusion of the knee. Flexion of the knee was to about 100 or 105 degrees. She lacked 10 degrees of extension of the knee. There was good collateral stability. There was more pain with forced extension. X-rays of the knee showed arthrosis. From November 2013 through December 2013, Orthovisc injections were administered to the Veteran's left knee. A January 2014 private treatment record reflects that the injections provided good relief. The Veteran's pain was significantly better. The swelling was down. However, she still could not fully extend the knee. Flexion of the knee was to about 120 degrees. There was good stability. Her gait was good. A VA examination was performed in March 2014 as part of the development of this claim. The examination report reflects a diagnosis of left knee degenerative joint disease. She experienced flare-ups described as "pain." On range-of-motion testing, flexion of the left knee was limited to 90 degrees, with objective evidence of painful motion beginning at that point. Extension was to 0 degrees, with no objective evidence of painful motion. There was no change in the degree of range of motion on repetitive-use testing. Muscle strength testing showed normal strength (5/5) of the knee. Joint stability tests were all normal. There was no evidence or history of recurrent patellar subluxation or dislocation. The Veteran had a history of a meniscal tear, but not a meniscectomy. She did not have meniscal dislocation, or frequent episodes of locking, pain, or joint effusion. Regarding the functional impact of the Veteran's left knee disability, the examiner found that the Veteran had pain, weakness, and/or incoordination, but no additional limitation of functional ability during flare-ups or with repeated use over time. A July 2014 letter from the Veteran's private treating orthopedic surgeon notes that two years earlier the Veteran had undergone ACL reconstruction and subsequent manipulation and debridement of the left knee (as discussed above). She still had pain and swelling at the end of the day. She did not have buckling. Her knee was very stiff, and she could not fully extend it. She limped when she walked. She stated that she was never able to get her full extension back after the surgery, and that if anything, the knee was getting stiffer and worse. On examination, there was no effusion. She lacked 25 degrees of full extension. Flexion of the knee was only to 95 degrees. She had good collateral stability. An x-ray study showed "collapse on the medial compartment." There was complete loss of joint space. The patellofemoral arthrosis was also worsened. The treating physician believed she had tricompartmental osteoarthritis. A September 2016 private physical therapy record reflects that the Veteran had not been able to straighten her knee for years, and could not bend it past 90 degrees. She reported difficulty with stairs due to motion restriction. She limped when ambulating and her knee swelled most of the time. On active range-of-motion testing, flexion of the left knee was limited to 85 degrees, and extension to -15 degrees. Passive range-of-motion testing showed flexion limited to 90 degrees and extension to -13 degrees. On October 17, 2016, the Veteran underwent a total left knee replacement (total arthroplasty) for increasingly progressive arthritis. A 100 percent rating has been assigned the total left knee replacement from October 17, 2016the date of the surgerythrough November 30, 2017. See 38 C.F.R. § 4.71a, Diagnostic Code 5055 (providing that a 100 percent rating will be assigned for the one-year period following implantation of prosthesis). From December 1, 2017, a 30 percent rating has been assigned. See id. A January 2018 private treatment record reflects that following the total left knee replacement, the Veteran continued to have knee pain and significantly restricted range of motion with flexion. Because the lack of normal motion, she could not bend down and had difficulty with stairs. She could not ride a bike because she lacked the range of motion to complete a full revolution of the pedal. She had pain with prolonged standing. She took Ibuprofen as needed ("PRN") for pain. She denied instability. She had been in physical therapy almost a full year, and was discharged in September 2017 because of lack of progression of motion. She was able to walk four to five miles. She no longer used an assistive device. On examination, she was minimally antalgic. She had moderate edema, which was noted to be normal post-op. On active range of motion testing, extension of the left knee was to 7 degrees, and flexion to 105 degrees, with pain during flexion. She had a negative varus and valgus stress test. She had 4+/5 strength of the knee with resisted flexion and extension, with pain. A VA examination was performed in June 2018 as part of the development of this claim. At the examination, the Veteran reported that she could straighten her leg completely, but was not able to fully flex it. Her left knee flexion was not enough to ride a bike or walk up steep stairs. She also had difficulty sitting in a restaurant and with prolonged sitting, difficulty climbing stairs, and was no longer able to run. She had stiffness and pain located throughout the anterior knee, and post-surgery residual swelling. She performed physical therapy exercises at home, and other exercises such as rowing, walking, and stationary bike. She took Ibuprofen and applied ice as needed ("PRN"). She did not report flare-ups. The June 2018 VA examination report reflects that on range-of-motion testing, flexion of the left knee was to 100 degrees, and extension to 0 degrees, with pain noted on flexion. There was no additional loss of range of motion on repetitive use testing. The examiner declined to provide estimates of any additional loss of motion during flare-ups or with repeated use over time. In that regard, the examiner stated that it was not possible to provide an estimate without resorting to mere speculation, as there was no conceptual or empirical basis for making such a determination without directly observing function under such conditions. The Board here notes that as the Veteran did not report flare-ups, the issue of whether she had additional functional loss during flare-ups was moot. Thus, the examiner's unwillingness to provide an estimate of functional loss during flare-ups does not affect the adequacy of the examination. Muscle strength testing showed normal (5/5) strength of the knee in both flexion and extension. There was no history of recurrent subluxation or lateral instability of the knee. The Veteran had recurrent effusion described as visible swelling surround the knee joint. Joint stability tests of the knee were all normal. Regarding the impact of the Veteran's left knee on occupational functioning, the June 2018 VA examiner stated that the Veteran did office work, and had lost 0 to 1 week work time in the past 12 months. She had difficulty with squatting, stooping, and kneeling. At the August 2019 Board hearing, the Veteran testified that in 2013, she could not straighten her knee beyond 15 degrees, and could not bend her knee beyond 90 degrees, so that she was unable to walk properly, go down steps, or "do a lot of things." By January 2016 she had reached a point where at times she could not walk at all. She stated that if she walked a quarter of a mile she would be in severe pain. She took prescribed narcotic medication about once per week because of the severity of the pain. She added that during flare-ups she could not move the knee; it was almost completely stiff and "almost became totally frozen." She stated that sometimes the knee would get locked and she would have to "pop it out." She stated that since the October 2016 knee replacement, she could only bend her knee to 100 degrees. She could not ride a bicycle or use stairs normally. She had "episodes of pain where all of a sudden it will . . . over straighten," at which times she experienced very severe intense shooting pain. At those times, she had to stop and catch her breath, ands then could walk on. She stated that it often aches, and that sometimes she takes Vicodin or Ibuprofen. An October 2019 VA treatment record reflects that the Veteran had experienced left knee pain for the past five to six months, with occasional catching. Range-of-motion testing showed extension to 0 degrees and flexion to 120 degrees. There was minimal swelling. A December 2019 private treatment record reflects that the Veteran's left knee was "completely pain free." However, she had issues with stiffness of the knee. On range-of-motion testing, extension was to 0 degrees, and flexion to 94 degrees. She did not exhibit a limp. A VA examination was performed in September 2020. The examination report reflects that the Veteran continued to have left knee pain. She stated that if she sat too long (two to four hours) she would get stiffness in the knee. She had weekly flare-ups. The flare-ups were characterized as severe, and lasted for "a minute or so." They were precipitated by exertion and alleviated by rest. She was unable to bend, twist, or run for prolonged periods without pain. The September 2020 VA examination reflects that on range-of-motion testing, flexion of the Veteran's left knee was to 140 degrees and extension to 0 degrees. The examiner indicated that the range of motion measurements were "all normal." The examiner noted that the Veteran exhibited pain in both flexion and extension, but that the pain did not result in functional loss. There was no loss of range of motion on repetitive use testing. The examiner indicated that the Veteran was not being examined immediately after repetitive use of the knee over a period of time or during a flare-up. The examiner also found that pain, weakness, fatigability, or incoordination did not significantly limit functional ability during flare-ups or with repeated use over time. The September 2020 VA examination further reflects that on muscle strength testing, the Veteran's left knee exhibited normal (5/5) strength in flexion and extension. On stability testing, the examiner found 1+ (0-5 millimeters) of posterior, medial, and lateral instability. The examiner noted that the Veteran had a history of a meniscus tear with frequent episodes of joint locking and joint pain. Regarding the functional impact of the Veteran's left knee disability, the examiner stated that she was unable to run, stand, bend, or twist the knee for prolonged periods without a pain flare. She was also unable to run more than one or two blocks without pain. In an August 2021 statement, the Veteran wrote that she believed that the September 2020 VA examination report contains a typographical error with regard to the range of flexion of her left knee. She believed the examiner meant to write "104," rather than "140." In that regard, the Veteran noted that she has never had normal flexion since the 2016 knee replacement. After a year of physical therapy, she was only able to bend her knee to 107 degrees on active range of motion testing, and to 112 degrees on passive testing, according to her statement. The Board finds that the range of flexion recorded in the September 2020 VA examination report was not a typographical error because the examiner also checked the box indicating that the measurements were normal. Both the examination template and VA regulation define normal range of flexion as being to 140 degrees. 38 C.F.R. § 4.71a, Plate II. Nevertheless, the Board agrees that the normal range of motion recorded in the September 2020 VA examination report does not comport with the evidence clearly and consistently showing that the Veteran has not had normal flexion of the knee. As will be shown, private physical therapy records dated after the September 2020 VA examination confirm that her range of motion of the knee had not returned to normal by the time of the September 2020 examination. Thus, the Board will disregard the range-of-motion findings in the September 2020 examination in this decision. That said, the Board finds that a new VA examination is not warranted on that basis, as there is ample evidence apart from that examination documenting the Veteran's range of motion of the left knee since her knee replacement. That evidence includes the June 2018 VA examination report, VA treatment records, and the private physical therapy records dated through January 2022. It also includes the Veteran's August 2019 hearing testimony. All of that evidence, including her testimony, uniformly shows flexion limited to about 100 degrees (with the December 2019 record showing flexion limited to 94 degrees and the October 2019 record showing flexion limited to 120 degrees). The Board's determination is based on that evidence. In October 2021, per the Board's remand, an addendum to the September 2020 VA examination report was provided by a different examiner addressing the issue of whether there is additional loss of range of motion of the Veteran's knee during flare-ups. The examiner reviewed that examination report and the Veteran's medical records and medical history. The examiner stated that it would not be possible to determine the amount of loss of range of motion during flare-ups without resort to speculation. The examiner explained that that this was not because of the examiner's own limited knowledge or aversion to offering such an opinion, but because of a lack of knowledge among the medical community at large, as there is no guidance as to how to make such estimates. A January 2022 private physical therapy record reflects that the Veteran reported functional limitations due to lack of range of flexion of the left knee, and pain while flexing. She reported occasionally going down stairs one step at a time, depending on the depth of the step. She had increased knee pain when sitting in confined spaces or when her feet were unsupported. She had difficulty getting in and out of a car as a passenger. She had to elevate her bicycle seat in order to do a full revolution of the pedal, which limited how much she rides her bicycle. Her main mode of exercise was walking. On active range-of-motion testing, flexion of the left knee was to 100 degrees, and extension to -1 degrees. Passive testing showed flexion to 102 degrees. At the end of the physical therapy session, active left knee flexion was to 105 degrees, and passive flexion to 110 degrees. She was advised to attend rehabilitative physical therapy for six weeks, with one visit per week. A. Left Knee Disability Prior to October 17, 2016 Prior to October 17, 2016the effective date of the 100 percent rating assigned for the one-year period following the total left knee replacementthe Veteran's left knee disability was rated under DC 5260, which applies to limitation of flexion of the leg, and DC 5257, which pertains to lateral instability. The Board will first address the diagnostic codes pertaining to range of motion of the knee. Under DC 5260, a 0 percent rating is assigned for flexion of the leg limited to 60 degrees; a 10 percent rating is assigned for flexion limited to 45 degrees; a 20 percent rating is assigned for flexion limited to 30 degrees; and a 30 percent rating is assigned for flexion limited to 15 degrees. 38 C.F.R. § 4.71a. Under DC 5261, a 0 percent rating is assigned for extension of the leg limited to 5 degrees; a 10 percent rating is assigned for extension limited to 10 degrees; a 20 percent rating is assigned for extension limited to 15 degrees; a 30 percent rating is assigned for extension limited to 20 degrees; a 40 percent rating is assigned for extension limited to 30 degrees; and a 50 percent rating is assigned for extension limited to 45 degrees. Id. Normal range of motion of the knee is defined as flexion to 140 degrees and extension to 0 degrees. 38 C.F.R. § 4.71a, Plate II. Separate ratings may be assigned under DC's 5260 and 5261 for limitation of flexion and limitation of extension of the same joint. VAOPGCPREC 9-2004 (Sept. 17, 2004). In evaluating disabilities of the musculoskeletal system, consideration must be given to functional loss, including due to weakness and pain, affecting the normal working movements of the body in terms of excursion, strength, speed, coordination, and endurance. 38 C.F.R. § 4.40. In this regard, pain "must actually affect some aspect of 'the normal working movements of the body' [under] 38 C.F.R. § 4.40 in order to constitute functional loss" warranting a higher rating. Mitchell v. Shinseki, 25 Vet. App. 32, 43 (2011). With respect to disabilities of the joints, it must be considered whether there is less movement or more movement than normal, weakened movement, excess fatigability, incoordination, and pain on movement, as well as swelling, deformity, or atrophy of disuse. 38 C.F.R. § 4.45. Accordingly, under sections 4.40 and 4.45, it must be determined whether a higher rating may be assigned based on functional loss of the affected joint on repeated use as a result of the above factors, including during flare-ups of symptoms, beyond any limitation reflected on one-time measurements of range of motion. DeLuca v. Brown, 8 Vet. App. 202, 206-07 (1995). However, a higher rating based on functional loss may not exceed the highest rating available under the applicable diagnostic code(s) pertaining to range of motion. See Johnston v. Brown, 10 Vet. App. 80, 85 (1997). Here, to assign a rating higher than 10 percent based on limitation of flexion of the knee, the evidence must show limitation to 30 degrees or less. See 38 C.F.R. § 4.71a, DC 5260. For the period prior to October 17, 2016, the private treatment records and the March 2014 VA examination report show that the Veteran's left knee flexion consistently exceeded 30 degrees. At its most limited, her flexion was to 85 degrees, which was shortly before the October 2016 total knee replacement. There is no indication that with flare-ups or repeated use over time, her flexion was limited to 30 degrees or less. Accordingly, a higher rating based on limited flexion is not warranted. With regard to limitation of extension, the Board finds that for the period from July 9, 2013 through July 13, 2014, the criteria for a separate 10 percent rating were met. The private treatment records show that the Veteran lacked about 10 degrees of extension of the left knee. Under DC 5260, extension limited to 10 degrees is assigned a 10 percent rating. The Board notes that the March 2014 VA examination report states that the Veteran's extension was to 0 degrees, or normal. However, she had received several Orthovisc injections shortly before the March 2014 VA examination. The January 2014 record notes that they provided good relief. The Veteran may have thus been still benefiting from the relief afforded by those injections at the time of the March 2014 examination. The Board may not disregard the ameliorative effects of medication in determining the appropriate rating to be assigned. Jones v. Shinseki, 26 Vet. App. 56, 61 (2012). Moreover, the March 2014 VA examination report is otherwise an outlier vis-à-vis the other records from that time period, which all show limitation of extension. Accordingly, it does not alter the Board's conclusion that a separate 10 percent rating is warranted. For the period from July 14, 2014 through October 16, 2016 (the day before the assignment of the 100 percent rating based on the total knee replacement), the Board finds that a separate 30 percent rating is warranted for limitation of extension. The letter from the Veteran's private treating physician dated July 14, 2014 states that on examination, the Veteran's extension was limited to 25 degrees. Under DC 5261, extension limited to 20 degrees is assigned a 30 percent rating. The Board finds that a rating higher than 30 percent based on limitation of extension is not warranted. A 40 percent rating is assigned for extension limited to 30 degrees under DC 5261. As extension limited to 25 degrees does not more nearly approximate extension limited to 30 degrees, assignment of the lower rating is appropriate. See 38 C.F.R. § 4.7. Moreover, although the Veteran's left knee progressively worsened, the September 2016 private treatment record shows extension limited to 15 degrees, for which a 20 percent rating is assigned under DC 5261. That finding puts into question whether the extension limited to 25 degrees recorded in the July 2014 letter was an accurate representation of her general disability picture at that time. Indeed, at the Board hearing, the Veteran stated that her extension had been limited to 15 degrees prior to the total knee replacement. Nevertheless, when considered in the context of the overall medical history including several prior surgeries, x-ray findings of tricompartmental arthritis, and the subsequent total knee replacement, the Board finds that a reasonable doubt arises on that issue, and resolves such doubt in the Veteran's favor. See 38 C.F.R. § 3.102. The Board also notes that even if there had been some improvement in extension following the July 2014 letter, it is not possible to determine when there was sufficient improvement to "stage" the rating down to 20 percent prior to September 2016. To assign a staged rating of 20 percent for the period between September 27, 2016the date of the record showing extension limited to 15 degreesand October 17, 2016 would be absurd. To summarize, a separate 10 percent rating for limitation of extension of the left knee is assigned from July 9, 2013 through July 13, 2014. A rating of 30 percent for limitation of extension is assigned from July 14, 2014 through October 16, 2016. As there is no indication that the Veteran had additional limitation of extension, including during flare-ups or with repeated use over time, higher ratings based on limitation of extension are not warranted. Regarding flare-ups, the Board has considered the fact that at the August 2019 Board hearing, the Veteran stated that by January 2016, when flare-ups occurred her knee became "completely stiff" or "almost . . . totally frozen." The Board finds that the separate 30 percent and 10 percent ratings based on limitation of extension and limitation of flexion capture that level of severity. In that regard, under DC 5256, a 40-percent rating is assigned for ankylosis of the knee when it is in flexion between 10 degrees and 20 degrees. Ankylosis means "immobility and consolidation of a joint due to disease, injury, or surgical procedure;" in essence, it is complete limitation of motion. Chavis v. McDonough, 34 Vet. App. 1, 8, 11 (2021) (internal quotation omitted). As the Veteran's extension was limited to about 15 degrees, her knee when "frozen" would presumably resemble ankylosis with the knee in flexion between 10 and 20 degrees. Thus, the combined 40-percent rating based on limitation of extension and flexion equates to the rating that would be assigned for immobility of the knee with it locked in flexion between 10 and 20 degrees, and thus captures those times when it was "completely stiff" or "frozen" during flare-ups. That said, the Veteran did in fact retain considerable, albeit limited, range of motion in general. Although she had reached a point where at times she could not walk, she did not state that generally she could not walk, but that her ability to walk was limited, and that there were times when she could not walk. The record does not show otherwise. The rating assigned is based on the overall disability picture as shown by the record. For these reasons, the Board finds that even taking into account flare-ups during which her knee became effectively immobile, a higher rating or ratings are not warranted. The Board finds that the separate ratings of 30 percent for limitation of extension effective July 14, 2014, 10 percent for limitation of flexion, and 10 percent for instability, which result in a combined evaluation of 40 percent under the combined ratings table in 38 C.F.R. § 4.25, adequately capture the severity of her knee disability at that time in terms of the rating criteria. The Veteran's left knee disability was also assigned a separate rating of 10 percent under DC 5257 prior to October 17, 2016. Diagnostic Code 5257 pertains to "other impairment" of the knee, with recurrent subluxation or lateral instability. Id. Under DC 5257, a 10-percent rating is assigned when such impairment is slight; a 20-percent rating is assigned when such impairment is moderate; and a 30-percent rating is assigned when such impairment is severe. Objective evidence of instability is not necessarily required to satisfy the criteria for a rating under DC 5257. English v. Wilkie, 30 Vet. App. 347, 353 (2018). The Board finds that a rating higher than 10 percent under DC 5257 is not warranted. Prior to October 17, 2016, the record does not show complaints or findings of instability during the period under review. An October 2013 record notes that the Veteran had no swelling or buckling of the knee. There was good collateral stability. The March 2014 VA examination report reflects that joint stability tests were all normal. The July 2014 letter by the treating orthopedic surgeon states that on examination, she had good collateral stability. The evidence also shows that the Veteran's left knee disability was not manifested by subluxation. Accordingly, as the evidence shows that the Veteran did not have instability or subluxation of the left knee prior to October 17, 2016, let alone moderate or severe instability or subluxation, the criteria for a rating higher than 10 percent under DC 5257 were not met. The Board has considered the applicability of other diagnostic codes pertaining to the knee, and finds that no other diagnostic code applies. Under DC 5258, a 20 percent rating is assigned for dislocated semilunar cartilage (i.e., the meniscus) with frequent episodes of "locking," pain, and effusion into the joint. 38 C.F.R. § 4.71a. As the Veteran's left knee disability was not manifested by a dislocated meniscus, DC 5258 does not apply. The Board also notes that it was not generally manifested by frequent episodes of locking. Her pain, stiffness, and swelling of the knee are contemplated by the ratings assigned under DC's 5260 and 5261. Diagnostic Code 5259 assigns a 10 percent rating for removal of the semilunar cartilage that is symptomatic. Id. As discussed, the Veteran underwent a partial medial and lateral meniscectomy in August 2012. The record does not show that she has had symptoms linked to that meniscectomy since July 2013. Rather, her symptoms were attributed to her arthritis. To the extent her pain or limitation of motion of the knee may be related to the meniscectomy, those manifestations are already compensated by the ratings assigned under DC's 5260 and 5261. Thus, to assign a separate rating under DC 5259 would result in compensating twice for the same disability under different diagnoses, in violation of the rule against pyramiding. See 38 C.F.R. § 4.14. The record shows that, prior to October 17, 2016, the Veteran's left knee disability was not manifested by ankylosis, impairment of the tibia and fibula, or genu recurvatum. Thus, DC's 5256, 5262, and 5263, which pertain to those conditions, respectively, do not apply. See 38 C.F.R. § 4.71a. As a final matter, because the Veteran's left knee disability has been assigned compensable ratings under DC's 5260 and 5261, a separate rating for arthritis of the knee under DC 5003 may not be assigned, as that is disallowed by the expression provisions of DC 5003, and by the rule against pyramiding. See 38 C.F.R. §§ 4.14, 4.71a (DC 5003). Because the persuasive evidence weighs against ratings higher than those assigned, as explained above, the benefit-of-the-doubt rule does not apply. See Lynch, supra; 38 U.S.C. § 5107. B. Left Knee Disability Since December 1, 2017 The Veteran's left knee disability was assigned a 100 percent rating from October 17, 2016 through November 30, 2017 based on the total knee replacement. See 38 C.F.R. § 4.71a, DC 5055. Thus, the period at issue begins December 1, 2017. Diagnostic Code 5055 pertains to prosthetic knee replacement. Id. Under DC 5055, after the on-year post-surgical period, a 60 percent rating is assigned for chronic residuals consisting of severe painful motion or weakness in the affected extremity. When there are intermediate degrees of residual weakness, pain, or limitation of motion, the left knee replacement is to be rated by analogy under DC's 5256, 5261, or 5262. The minimal rating to be assigned is 30 percent. Id. Here, the Board finds that a rating higher than 30 percent under DC 5055 is not warranted. The Veteran's residuals of her left knee replacement are not shown to be manifested by severe painful motion or weakness. The fact that she continues to have some pain, stiffness, and limitation of motion, which have prevented her from using a bike without raising the seat, and make it difficult to use stairs, for example, is captured by the 30 percent rating. The January 2018 private treatment record shows that she was able to walk four to five miles. She had moderate edema, which was noted to be normal post-op. Her knee had 4+/5 strength, which is almost normal and thus weighs against "severe" weakness. A higher rating based on intermediate degrees of residual pain, weakness, or limitation of motion by rating the knee replacement by analogy to DC's 5256, 5260, or 5261 would not yield a rating higher than 30 percent. The Veteran has not had ankylosis or immobility of the knee; thus DC 5256 is not applicable. Her left knee extension has generally been shown to be normal with the exception of the January 2018 private treatment record. That record shows that on active range of motion testing, extension of the left knee was to 7 degrees, and flexion to 105 degrees. Flexion to 105 degrees well exceeds flexion limited to 45 degrees, which is the criteria for a 10 percent rating under DC 5260. Extension to 7 degrees more nearly approximates the criteria for a 10-percent rating under DC 5261. The 30-percent rating under DC 5055 is higher than a combined rating of 20 percent by assigning separate 10-percent ratings under DC's 5260 and 5261. The Veteran's left knee replacement may not be assigned ratings under both DC 5055 and DC's 5060 and 5061, as indicated by the provisions of DC 5055, and because that would amount to pyramiding. See 38 C.F.R. § 4.14. Since the January 2018 private treatment record, examination findings have showed normal extension, and flexion exceeding 60 degrees. At worst, it was recorded as limited to 94 degrees. Thus, to assign a rating based on limitation of flexion under DC 5260 would not result in a rating higher than the 30 percent rating assigned under DC 5055. As the Veteran's extension of the left knee has been normal, DC 5261 does not apply. Regarding flare-ups, the Board has considered the fact that at the Board hearing, the Veteran stated that she has "episodes of pain where all of a sudden [her knee] will... over straighten," at which times she experiences very severe intense shooting pain. She stated that at those times, she had to stop and catch her breath, and then could walk on. At the September 2020 VA examination, she stated that the flare-ups were severe, occurred on a weekly basis, and lasted for "a minute or so." In determining whether a higher rating is warranted based on flare-ups, their frequency and duration must be considered. Cf. Voerth v. West, 13 Vet. App. 117, 122-23 (1999) (observing that "temporal considerations are important" when determining whether a VA examination must be performed during a flare-up, and that occasional short-lived flare-ups must be distinguished in this regard from those cases where a person experiences a worsened condition for weeks or months which impairs earning capacity). Here, both the Veteran's August 2019 hearing testimony and the September 2020 VA examination report indicate that her flare-ups are highly intermittent and short-lived. A flare-up that occurs for one minute once per week, even if severe, is not a basis for assigning a higher rating, either under DC 5055 based on residual pain and weakness, or under DC's 5260 or 5261. Rather, the rating must be based on the overall disability picture as it generally manifests, since the evaluations provided in the rating schedule are predicated on how the disability at issue affects average impairment of earning capacity. See 38 C.F.R. § 4.1. The January 2018 private treatment record states that she was able to walk four to five miles. The June 2018 VA examination report reflects that she engaged in exercises at home such as rowing, walking, and stationary bike. The January 2022 private physical record states that her main mode of exercise was walking. Accordingly, the Board finds it would not be appropriate to evaluate the Veteran's residuals of her total knee replacement based on flare-ups given their intermittent and fleeting nature. The Board notes that in the October 2021 opinion, the examiner declined to provide an estimate of additional functional loss during flare-ups. The examiner explained that this was owing to the fact that the medical community in general could not provide such estimates as there were no guidelines for doing so, rather than due to any deficiency in the examiner's own expertise or a lack of willingness to provide an estimate. The Board finds that explanation is adequate, and indeed provides one of the reasons suggested by the United States Court of Appeals for Veterans Claims (Court) as to why such an opinion might not be possible. See Sharp v. Shulkin, 29 Vet. App. 26, 35 (2017); see also Jones v. Shinseki, 23 Vet. App. 382, 390 (2010). The Board also finds it evident that it would not be possible to provide an estimate of additional loss of range of motion without resort to speculation when a flare-up generally occurs once per week and lasts about a minute. See Jones, 23 Vet. App. at 391. In any event, because the Board finds that it would be inappropriate to assign a disability rating based on the Veteran's short-lived flare-ups in this case, as explained in the preceding paragraph, further medical opinion on that issue is not warranted. The evidence shows that the Veteran does not otherwise have severe painful motion or weakness of the left knee. At the August 2019 hearing, she stated that it often aches. The 30-percent rating under DC 5055 contemplates residuals of a total knee replacement including pain and weakness. The Board finds that the fact that her knee often aches does not amount to severe painful motion. The Veteran's difficulties with prolonged sitting, especially in confined spaces such as cars, climbing stairs, riding a bicycle, and squatting, stooping, and kneeling, and her inability to run, are reflective of her continuing disability from her left knee replacement, for which a 30 percent rating has been assigned. However, severe painful motion or weakness is not shown. With regard to weakness, muscle strength testing at the June 2018 and September 2020 VA examinations was normal (5/5) in both flexion and extension. With regard to painful motionto put the matter into perspectiveflexion of her left knee has generally been to 100 degrees, which well exceeds the minimum 60 degrees required for a 0 percent rating under DC 5260. At worst, it was to 94 degrees, as reflected in the December 2019 private treatment record, which also notes that she was pain free at that time. Further, she has had normal range of extension of the knee without pain. Accordingly, the Board finds that the criteria for a rating higher than 30 percent under DC 5055 have not been met. By the same token, for the reasons discussed, to rate intermediate degrees of residual weakness, pain, or limitation of motion by analogy to DC's 5256, 5260, and 5261 would not result in a higher evaluation. She does not have the functional equivalent of immobility or ankylosis of the knee, and thus her knee replacement is not analogous to DC 5256. Rather, she has had normal extension, and flexion generally to 100 degrees. As explained, her left knee flexion does not meet the criteria for even a 0 percent rating under DC 5260. As explained, the limitation of extension shown in the January 2018 record would not result in a higher rating by applying DC 5261, and is not shown on subsequent examination. The Board notes that the September 2020 VA examiner found 1+ instability of the knee on stability testing. As no other examiner before or after that examination, including in the private treatment records, found instability of the knee, and as the Veteran has not reported experiencing instability, the Board finds that a separate compensable rating for slight instabilitylet alone higher ratings for moderate or severe instabilityunder DC 5257 is not warranted. The Board may not disregard the ameliorative effects of medication in evaluating the Veteran's left knee disability. Jones v. Shinseki, 26 Vet. App. 56, 61 (2012). The Board has considered the fact that the Veteran sometimes takes Vicodin or Ibuprofen for pain. The record does not show that absent such medication she would have severe painful motion or weakness of the left knee, or that flexion of the left knee would be limited to 45 degrees or less, or extension limited to 10 degrees or moreor limited to 30 degrees or more prior to October 17, 2016, including during flare-ups. It is also not evident that the range-of-motion testing in the VA examination reports and VA and private treatment records coincided with the Veteran's taking of Vicodin or Ibuprofen, such that she was benefiting from any ameliorative effects of medication during the examinations or testing. Thus, when considering the ameliorative effects of medication, the criteria for ratings higher than those assigned have not been met. The record shows that since October 17, 2016, the Veteran's left knee replacement has not been manifested by ankylosis, dislocated semilunar cartilage with frequent episodes of "locking," pain, and effusion into the joint, symptomatic removal of the semilunar cartilage, impairment of the tibial and fibula, or genu recurvatum. Accordingly, DC's 5256, 5258, 5259, 5262, and 5263, which pertain to those conditions, respectively, do not apply. See 38 C.F.R. § 4.71a. The Board notes that revisions to the rating schedule applicable to the musculoskeletal system went into effect on February 7, 2021. See Schedule for Rating Disabilities: Musculoskeletal System and Muscle Injuries, 85 Fed. Reg. 76453 (Nov. 30, 2020). The Board may consider these changes without remand to the AOJ for consideration in the first instance. See 38 C.F.R. § 20.904(d)(2). The Board may not apply a current regulation prior to its effective date unless the regulation explicitly provides otherwise. VAOPGCPREC 7-2003 (Nov. 19, 2003); Kuzma v. Principi, 341 F.3d 1327 (Fed. Cir. 2003) (overruling Karnas v. Derwinski, 1 Vet. App. 308 (1991) to the extent it conflicts with the precedents of the United States Supreme Court and the Federal Circuit). Thus, the changes to the rating schedule that went into effect on February 7, 2021 do not apply prior to that date. See id.; 85 Fed. Reg. 76453. The changes made to the rating schedule with respect to the knee pertain to DC 5055 (resurfacing or replacement (prosthesis)), DC 5257 (other impairment of, recurrent subluxation or instability, patellar instability), and DC 5262 (tibia and fibular, impairment of). 85 Fed. Reg. at 76463. Diagnostic Code 5055 was amended to include resurfacing of the knee. Under new DC 5055, the time period for the assignment of the 100 percent rating following implantation of the prosthesis or resurfacing is limited to 4 months. New DC 5055 also specifies that the rating criteria for residuals only apply to prosthetic replacement of the knee joint, and that the minimum evaluation of 30 percent only applies to a total replacement, not resurfacing. Resurfacing is to be evaluated under diagnostic codes 5256 through 5262 at the conclusion of the 100 percent evaluation period. It is clear that application of new DC 5055, to the extent it differs from the prior version, would not be more favorable to the Veteran than application of the prior version. Moreover, the Veteran did not have resurfacing of the knee, but rather a total knee replacement. As discussed above, DC's 5257 and 5262 do not apply. Because the persuasive evidence weighs against a rating higher than 30 percent for the Veteran's left knee replacement since December 1, 2017, as explained above, the benefit-of-the-doubt rule does not apply. See Lynch, supra; 38 U.S.C. § 5107. P.M. DILORENZO Veterans Law Judge Board of Veterans' Appeals Attorney for the Board J. Rutkin, 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.