Citation Nr: 21072154 Decision Date: 12/02/21 Archive Date: 12/02/21 DOCKET NO. 17-66 477 DATE: December 2, 2021 ORDER Service connection for a right knee disorder, to include as secondary to the service-connected left knee disability and on a chronic disease presumptive basis, is denied. For the rating period on appeal from June 30, 2016, an increased disability rating in excess of 20 percent for the service-connected post-operative medial meniscectomy, anterior cruciate ligament reconstruction of left knee with degenerative arthritis (left knee disability) is denied. For the rating period on appeal from June 30, 2016, a separate 10 percent disability rating for slight left knee instability is granted. FINDINGS OF FACT 1. The Veteran has present diagnoses of right knee chondromalacia patella and arthritis. 2. There was no in-service right knee injury, disease, or event. 3. Symptoms of right knee arthritis were not chronic during service, were not continuous since service separation, and did not manifest to a compensable degree within one year of service separation. 4. The Veteran is service connected for a left knee disability. 5. The Veteran does not have an altered gait or compensation due to the left knee disability. 6. The left knee disability does not cause or worsen in severity beyond a normal progression the right knee disorder. 7. For the increased rating period on appeal from June 30, 2016, the symptomatology and functional impairment of the service-connected left knee disability most nearly approximated dislocated semilunar cartilage with frequent episodes of "locking," pain, and effusion into the joint; the symptomatology and functional impairment did not more nearly approximate compensable limitation of flexion or extension, genu recurvatum, or ankylosis. 8. For the rating period on appeal from June 30, 2016, the symptomatology and functional impairment of the service-connected left knee disability most nearly approximated slight lateral instability. CONCLUSIONS OF LAW 1. The criteria for service connection for a right knee disorder, to include as secondary to the service-connected left knee disability and on a chronic disease presumptive basis, are not met. 38 U.S.C. §§ 1110, 1112, 1131, 1137, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309, 3.310. 2. For the increased rating period on appeal from June 30, 2016, the criteria for an increased disability rating in excess of 20 percent for the service-connected left knee disability have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.20, 4.71a, Diagnostic Code 5258. 3. Resolving reasonable doubt in favor of the Veteran, for the rating period on appeal from June 30, 2016, the criteria for a separate 10 percent disability rating for slight lateral left knee instability have been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.20, 4.71a, Diagnostic Code 5257. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran, who is the appellant, had active duty service from October 1983 to February 1984 and from September 1986 to February 1990. The instant matters are on appeal from Department of Veterans Affairs (VA) Regional Office (RO) rating decisions. The Veteran testified before the undersigned Veterans Law Judge at a Board of Veterans' Appeals (Board) hearing in July 2021. The hearing transcript has been associated with the claims file. Service Connection Legal Criteria Direct Service Connection Service connection can be granted for a disability resulting from a disease or injury incurred in or aggravated by active service. 38 U.S.C. §§ 1110, 1131; 38 C.F.R. § 3.303(a). Service connection may be granted for any disease diagnosed after discharge when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d). Service connection generally requires (1) medical evidence of a current disability; 2) medical or, in certain circumstances, lay evidence of an in-service incurrence or aggravation of a disease or injury; and 3) medical evidence of a nexus between the claimed in-service disease or injury and the current disability. Chronic Disease Presumptive Service Connection Arthritis is a "chronic disease" under 38 C.F.R. § 3.309(a). For these reasons, the presumptive service connection provisions under 38 C.F.R. § 3.303(b) for service connection based on "chronic" symptoms in service and "continuous" symptoms since service are applicable. Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir 2013). For the showing of chronic disease in service, there is required a combination of manifestations sufficient to identify the disease entity, and sufficient observation to establish chronicity at the time. With chronic disease as such in service, subsequent manifestations of the same chronic disease at any later date, however remote, are service connected, unless clearly attributable to intercurrent causes. If a condition noted during service is not shown to be chronic, then generally, a showing of continuity of symptoms after service is required for service connection. 38 C.F.R. § 3.303(b). Additionally, where a veteran served ninety days or more of active service, and certain chronic diseases become manifest to a degree of 10 percent or more within one year after the date of separation from such service, such disease shall be presumed to have been incurred in service, even though there is no evidence of such disease during the period of service. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.307, 3.309(a). While the disease need not be diagnosed within the presumption period, it must be shown, by acceptable lay or medical evidence, that there were characteristic manifestations of the disease to the required degree during that time. Id. Secondary Service Connection Service connection may be granted for a condition that is caused or aggravated by a service-connected disability. 38 C.F.R. § 3.310. To prevail on the issue of secondary service connection, the record must show (1) evidence of a current disability, (2) evidence of a service-connected disability, and (3) nexus evidence establishing a connection between the current disability and the service-connected disability, which relates to either causation or aggravation. See id. 1. Service Connection for a Right Knee Disorder is Denied. The Veteran seeks service connection for a right knee disorder, which has been diagnosed as chondromalacia patella (June 2014 MRI) and arthritis (July 2017 VA Examination). The present disability requirement has been met. Regarding direct service connection, the weight of the lay and medical evidence shows no in-service right knee injury, disease, or event, and the Veteran has not contended that there was an in-service injury, disease, or event. While the Veteran had some other orthopedic complaints during service, including a sprained left knee, a left knee MCL tear, left knee surgery, shoulder injury, and a sprained thumb, the evidence does not similarly show an injury, disease, or event involving the right knee. The Veteran sought treatment during service for non-orthopedic ailments as well, to include a rash, sinus pain, cold, and flu. Right knee symptoms are such that they would be included in the service treatment (medical) records had the symptoms occurred; therefore, the absence of any right knee complaints or findings or symptoms during service, in the context of other specific complaints and findings during service, is evidence that supports the finding that there was no right knee in-service injury, disease, or event during service. See Kahana v. Shinseki, 24 Vet. App. 428, 438 (2011) (stating that VA may use silence in the service treatment records as evidence contradictory to a veteran's assertions if the service treatment records appear to be complete and the injury, disease, or symptoms involved would ordinarily have been recorded had they occurred) (Lance, J., concurring); Buczynski v. Shinseki, 24 Vet. App. 221, 224 (2011) (citing Fed. R. Evid. 803(7) for the proposition that the absence of an entry in a record may be evidence against the existence of a fact that would ordinarily be recorded). Because there was no in-service right knee injury, disease, or event, service connection on a direct basis must be denied. See 38 C.F.R. § 3.303(a),(d). Concerning chronic disease presumptive service connection (38 C.F.R. § 3.303(b)), the diagnosis of arthritis means that chronic disease presumptive service connection principles are applicable. The Veteran has not argued that there were continuous right knee arthritis symptoms since service to warrant service connection in this case. There were no symptoms of a right knee injury, disease, or event during service, and the same evidence shows no chronic symptoms of right knee arthritis during service. The record also shows no continuous post-service symptomatology or that symptoms of right knee arthritis manifested to a compensable degree within one year of service separation. The Veteran sought treatment from a private orthopedist, Dr. F., in 2014. This is close to 25 years after service separation. Even allowing for some time to pass for the symptoms to develop before seeking treatment, this gap in time weighs heavily against finding continuous right knee arthritis symptomatology since service. Accordingly, service connection on a chronic disease presumptive service connection theory (38 C.F.R. § 3.303(b)) must be denied. The focus of the Veteran's attention during the July 2021 Board hearing was on secondary service connection (38 C.F.R. § 3.310), namely, that the service-connected left knee disability somehow caused or aggravated the right knee disorder. The Veteran theorized that the left knee disability may have inadvertently led to gait alteration or compensation, which in turn may have led to the current right knee disorder. After a review of all the evidence, lay and medical, the Board finds that the weight of the evidence is against a finding of secondary service connection, as the weight of the evidence shows that the service-connected left knee disability did not in fact cause gait alteration or compensation. Regarding the gait alteration, at the July 2021 Board hearing, the undersigned Veterans Law Judge asked the Veteran to describe his gait alteration or compensation. The Veteran stated that he walks normally, but tries to suggest the fact of altered gait by saying that he could be "inadvertently" favoring one side of the body because he was not in total comfort on the left side. The Veteran tries to suggest gait alteration or compensation, arguing that such gait alteration or compensation could be done "unconsciously" because the body became accustomed to the postural change. The Veteran is competent to report that he walks with an altered gait due to favoring the left knee; however, that is not his testimony. The Veteran himself admitted that he walks normally, and that any alteration might be inadvertent. The testimony shows that the Veteran does not notice any alteration of gait. If the Veteran himself does not even notice any altered gait, then he does not have an altered gait. This testimony shows that there is in fact no gait alteration or even noticeable compensation. The reasons the Veteran proffers for not noticing the presence of any altered gait are simply contentions that there is a possibility of an altered gait that was so insignificant not to be noticeable. This testimony is simply as contention that there could be altered gait, but is not testimony that in fact he has an altered gait. Consistent with the Board's finding that the Veteran does not in fact have an altered gait are findings from a January 2015 VA Examination, in which the VA examiner assessed that the physical examination of the right knee was normal and the Veteran's gait was normal. Again at a July 2017 VA Examination, the VA examiner examined the Veteran and concluded that the gait was unaltered. Although the Veteran submitted three notes from a private orthopedist, Dr. F., the notes simply assumed as a fact that there was compensation without providing any explanation or description of how such compensation was observed. Regarding the purported opinions that address the question of nexus between the left knee disability and the right knee disorder, the Board finds the opinions of the VA examiners to be more persuasive than those of Dr. F. because the VA opinions are supported by a fully developed rationale and rely on accurate facts as found by the Board, including the significant fact that there is no altered gait pattern caused by the service-connected left knee disability. See Hernandez-Toyens v. West, 11 Vet. App. 379, 382 (1998) (stating that whether a medical professional provides a basis for the medical opinion goes to the weight or credibility of the evidence in the adjudication of the merits); Stefl v. Nicholson, 21 Vet. App. 120, 124 (2007) (stating that a medical opinion must support its conclusion with analysis that the Board can consider and weigh against contrary opinions); Reonal v. Brown, 5 Vet. App. 458, 461 (1993) (holding that the Board may reject a medical opinion based on an inaccurate factual basis). While the two VA opinions were written by nurse practitioners and the opinions provided by Dr. F. were by an orthopedist, who is a specialist, the Board finds that the additional training and education of the orthopedist was never utilized in the opinions provided, as the orthopedist simply wrote conclusory statements that did not draw on his medical knowledge or training or experience. Instead, the orthopedist's statements assumed inaccurately that there was altered gait (without explaining even how this assumption was derived). The orthopedist did not utilize any specialized training or experience to explain what factors would cause such a secondary relationship between the knees; in short, the orthopedist provided no rationale for the conclusory statements of secondary relationship, and provided no orthopedic or medical explanation (based on education or anything else other than an inaccurate fact of altered gait) to support the conclusory statements. The VA opinions are be more persuasive because the VA examiner's opinions were supported with a rationale that included explanation of what conditions are needed to create such an altered gait and secondary effects, assumed accurately that there was no altered gait in this case, and recognized that there was no altered gait significant enough to cause a secondary opposite knee disability. In the January 2015 VA Examination, the VA examiner issued a negative nexus opinion, reasoning that, although research indicates that an injury in one leg can cause a problem in the uninjured leg, the association occurs in cases like (1) when the damage to the leg results in a major displacement of the center of gravity of the body while walking, e.g., severe Trendelenburg lurch, which this Veteran does not have as he has stable gait, (2) when there is significant shortening of the injured leg greater than 4-5 centimeters, which this Veteran does not have, and (3) when the altered gait pattern is present for a long period of time, which this Veteran does not have. The January 2015 VA examiner further reasoned that, because the Veteran's physical examination of the right knee was normal and the gait was normal, none of the identified factors applied to show that the Veteran's left knee acted upon the right knee to cause a disability (either causation or aggravation). The Board finds this opinion persuasive because it relies on medical literature and provides a detailed rationale that links the (accurate) facts specific to this Veteran to the known medical principles. In a July 2017 VA Examination, the VA examiner issued a negative nexus opinion using the same general information, reiterating that the Veteran did not exhibit a Trendelenburg lurch, leg length discrepancy, or altered gait (limp). The July 2017 VA examiner specifically considered the statements proffered by Dr. F. when reaching this conclusion. The Veteran has submitted three statements by Dr. F. In an August 2014 note, Dr. F. wrote that, because of left knee pain, the Veteran "has compensated and now developed some right knee patellofemoral syndromes." Dr. F. assumed as a fact that there was such compensationwhich is inconsistent with the facts found by the Board in this decision based on lay and medical evidenceand did not provide a rationale to support the conclusion that the left knee pain somehow acted on the right knee to cause the development of right knee patellofemoral syndromes. This opinion is given no probative weight because it is based on the inaccurate factual basis of the presence of compensation, contrary to the facts found by the Board in this case based on consideration of all evidence of record, lay and medical. See Reonal, 5 Vet. App. at 461; Stefl, 21 Vet. App. at 124. In a March 2015 note, Dr. F. wrote that he feels that at least 50 percent of the right knee symptoms are secondary to compensation for the left knee injury. Dr. F. again inaccurately assumes as a fact that there was compensation, without explaining what history or findings support such a conclusion, and again provides no rationale to support the conclusion that the left knee pain somehow acted on the right knee to cause 50 percent of the right knee symptoms (notably, not addressing causation of the actual right knee disability, but only the symptoms). Accordingly, given the absence of rationale and inaccurate factual assumption, the opinion is not given probative weight. See Reonal at 461; Stefl at 124. The third opinion by Dr. F. is more detailed. In a December 2016 letter, Dr. F. stated that it was his professional opinion that the right knee symptoms are related to the (factually assumed) compensation that the Veteran was undergoing with (factually assumed) altered gait due to left knee chronic instability (rather than from left knee pain as originally stated). Dr. F. again purported to opine that the right knee is more likely than not secondary to compensation for the left knee instability, which has resulted in right knee patellofemoral chondromalacia symptoms. Dr. F. also does not attempt to reconcile this new opinion (that left knee instability caused compensation) with the two prior opinions (that left knee pain caused compensation). This purported opinion also provides no rationale to support the conclusion that the left knee instability somehow acted on the right knee to cause the right knee disorder. The Board's finding of fact in this decision (rating the service-connected knee disability) is that the left knee instability, which is barely detectable on clinical measures, has not been more than slight. There is no rationale to support how slight left knee instability allegedly caused the right knee disability, and the nature of the left knee instability that is only slight makes no such suggestion of altered gain or compensation. In short, after a review of all the evidence, the lay and medical evidence weighs against a finding of gait alteration/compensation due to the left knee disability; as there is in fact no such altered gait or compensation, there is no factual basis for a suggestion or factual assumption that gait alteration/compensation could lead to the right knee disorder. In addition, there is no rationale that would explain how such secondary relationship might occur, including no rationale based on the accurate facts of this case. For these reasons, the opinions of the VA examiners are more persuasive because they provide a more detailed rationale that is consistent with the facts as found by the Board of no compensation/alteration. Accordingly, service connection for right knee disorder on a secondary basis (38 C.F.R. § 3.310) must be denied. Disability Rating Legal Criteria Disability ratings are determined by applying the criteria set forth in the VA Schedule for Rating Disabilities (Rating Schedule) found in 38 C.F.R. Part 4. 38 U.S.C. § 1155. It is not expected that all cases will show all the findings specified; however, findings sufficiently characteristic to identify the disease and the disability therefrom and coordination of rating with impairment of function will be expected in all instances. 38 C.F.R. § 4.21. Where there is a question as to which of two disability ratings shall be applied, the higher rating 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. It is the defined and consistently applied policy of VA to administer the law under a broad interpretation, consistent, however, with the facts shown in every case. When after careful consideration of all procurable and assembled data, a reasonable doubt arises regarding the degree of disability such doubt will be resolved in favor of the claimant. 38 C.F.R. § 4.3. In general, all disabilities, including those arising from a single disease entity, are rated separately, and all disability ratings are then combined in accordance with 38 C.F.R. § 4.25. Pyramiding, the rating of the same disability, or the same manifestation of a disability, under different diagnostic codes, is to be avoided when rating a veteran's service-connected disabilities. 38 C.F.R. § 4.14. It is possible for a veteran to have separate and distinct manifestations from the same injury which would permit rating under several diagnostic codes; however, the critical element in permitting the assignment of several ratings under various diagnostic codes is that none of the symptomatology for any one of the conditions is duplicative or overlapping with the symptomatology of the other condition. Esteban v. Brown, 6 Vet. App. 259, 261-62 (1994); Lyles v. Shulkin, 29 Vet. App. 107 (2017) (holding that 38 C.F.R. § 4.14 prohibits compensating a veteran twice for the same symptoms or functional impairment). When rating disabilities of the musculoskeletal system, 38 C.F.R. § 4.40 allows for consideration of functional loss due to pain and weakness causing additional disability beyond that reflected on range of motion measurements. DeLuca v. Brown, 8 Vet. App. 202 (1995). Further, 38 C.F.R. § 4.45 provides that consideration also be given to decreased movement, weakened movement, excess fatigability, incoordination, and pain on movement, swelling, and deformity or atrophy of disuse. Painful motion is considered limited motion at the point that pain actually sets in. See VAOPGCPREC 9-98. With any form of arthritis, painful motion is an important factor of disability, the facial expression, wincing, etc., on pressure or manipulation, should be carefully noted and definitely related to affected joints. Muscle spasm will greatly assist the identification. The intent of the schedule is to recognize painful motion with joint or periarticular pathology as productive of disability. It is the intention to recognize actually painful, unstable, or malaligned joints, due to healed injury, as entitled to at least the minimum compensable rating for the joint. Crepitation either in the soft tissues such as the tendons or ligaments, or crepitation within the joint structures should be noted carefully as points of contact which are diseased. Flexion elicits such manifestations. The joints involved should be tested for pain on both active and passive motion, in weight-bearing and non-weight-bearing and, if possible, with the range of the opposite undamaged joint. 38 C.F.R. § 4.59. The most appropriate diagnostic codes for rating limitation of motion of the knee are Diagnostic Codes 5260 and 5261. 38 C.F.R. § 4.71a. 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. In VAOPGCPREC 9-2004, the VA General Counsel interpreted that, when considering Diagnostic Codes 5260 and 5261 together with 38 C.F.R. § 4.71, a veteran may receive a rating for limitation in flexion only, limitation of extension only, or, if the 10 percent criteria are met for both limitations of flexion and extension, separate ratings for limitations in both flexion and extension under Diagnostic Code 5260 (leg, limitation of flexion) and Diagnostic Code 5261 (leg, limitation of extension). Under Diagnostic Code 5260, limitation of knee flexion is rated 30 percent disabling where flexion is limited to 15 degrees; 20 percent disabling where flexion is limited to 30 degrees; 10 percent disabling where flexion is limited to 45 degrees; and noncompensable where flexion is limited to 60 degrees. 38 C.F.R. § 4.71a. Under Diagnostic Code 5261, limitation of knee extension is rated 50 percent disabling where extension is limited to 45 degrees; 40 percent disabling where extension is limited to 30 degrees; 30 percent disabling where extension is limited to 20 degrees; 20 percent disabling where extension is limited to 15 degrees; 10 percent disabling where extension is limited to 10 degrees; and noncompensable where extension is limited to 5 degrees. 38 C.F.R. § 4.71a. Under Diagnostic Code 5256, ankylosis of the knee that is in the favorable angle in full extension, or is in slight flexion between 0 degrees and 10 degrees, warrants a 30 percent disability rating. Ankylosis of the knee in flexion between 10 degrees and 20 degrees warrants a 40 percent disability rating. Ankylosis of the knee in flexion between 20 degrees and 45 degrees warrants a 50 percent disability rating. Extremely unfavorable ankylosis of the knee, in flexion at an angle of 45 degrees or more, warrants a 60 percent rating. A 60 percent rating is the maximum schedular disability rating available under Diagnostic Code 5256. Id. Ankylosis is the immobility and consolidation of a joint. Lewis v. Derwinski, 3 Vet. App. 259 (1992). Diagnostic Code 5258 provides a 20 percent disability rating when a dislocated semilunar cartilage is present with frequent episodes of "locking," pain, and effusion into the joint. Diagnostic Code 5259 provides for a 10 percent disability rating when semilunar cartilage has been removed and related symptoms are present. A 10 percent disability rating is assigned under Diagnostic Code 5263 when genu recurvatum is identified. 38 C.F.R. § 4.71a. Diagnostic Code 5003 provides that degenerative arthritis established by x-ray findings is to be evaluated on the basis of limitation of motion under the appropriate diagnostic code for the specific joint or joints involved. When, however, the limitation of motion of the specific joint or joints involved is noncompensable under the appropriate diagnostic code, a rating of 10 percent is for application for each such major joint or group of minor joints affected by limitation of motion, to be combined, not added under Diagnostic Code 5003. 38 C.F.R. § 4.71a. 38 C.F.R. § 4.71a was amended effective February 7, 2021. The amendment pertaining to the knees concerns Diagnostic Code 5257, which provided explicit definitions and ratings for different degrees of recurrent subluxation or lateral instability and for patellar instability. Schedule for Rating Disabilities: Musculoskeletal System and Muscle Injuries, 85 Fed. Reg. 76453, 76463 (Nov. 30, 2020) (to be codified at 38 C.F.R. § 4.71a, Diagnostic Code 5257). For recurrent subluxation or lateral instability, 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 warrants a 30 percent rating. A sprain, incomplete tear, or repaired complete ligament tear causing persistent instability and a medical provider prescribes a brace and/or assistive device for ambulation warrants a 20 percent rating. An unrepaired or failed repair of complete ligament tear causing persistent instability; and a medical provider prescribes either an assistive device or bracing for ambulation warrants a 20 percent rating. 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 assistive device or bracing for ambulation warrants a 10 percent rating. Id. For patellar instability, 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 walker warrants a 30 percent rating. A diagnosed condition involving the patellofemoral complex with recurrent instability after surgical repair that requires a prescription from a medical provider for one of the following: a brace, cane, or walker warrants a 20 percent rating. A diagnosed condition involving the patellofemoral complex with recurrent instability with or without history of surgical repair that does not require a prescription from a medical provider for a brace, cane, or walker warrants a 10 percent rating. Note (1) explains that for patellar instability, the patellofemoral complex consists of the quadriceps tendon, the patella, and the patellar tendon. Note (2) provides that a surgical procedure that does not involve repair of one or more patellofemoral components that contribute to the underlying instability shall not qualify as surgical repair for patellar instability (including, but not limited to, arthroscopy to remove loose bodies and joint aspiration). Id. 2. Rating the Left Knee Disability from June 30, 2016 The Veteran is currently in receipt of a 20 percent disability rating for the left knee disability on the basis of Diagnostic Code 5258 dislocated semilunar cartilage with frequent episodes of "locking," pain, and effusion into the joint. The Veteran has been in receipt of a rating pursuant to this Diagnostic Code for over 20 years. Accordingly, this specific 20 percent rating is protected from reduction pursuant to 38 C.F.R. § 3.951(b) unless there is a showing of fraud, which has not been alleged or proven in this case. See October 2017 Rating Decision (vacating a prior rating decision that discontinued the previously established 20 percent evaluation under Diagnostic Code 5258, concluding that such discontinuance was clear and unmistakable error because of the protection of 38 C.F.R. § 3.951(b)). The question becomes whether a higher rating than 20 percent pursuant to any other Diagnostic Code is warranted for the left knee disability. The lay or medical evidence does not show ankylosis (Diagnostic Code 5256) or genu recurvatum (Diagnostic Code 5263). Additionally, although there is a mild reduction in limitation of flexion (Diagnostic Code 5260) it is not even to a compensable degree, much less to a degree of greater than 20 percent disabling. In the August 2016 VA Examination, flexion was reduced to 125 degrees, including for consideration of pain and repetition, and the examination was being conducted during a flare-up. The December 2016 letter from Dr. F. and other orthopedic treatment records in the file do not provide a flexion measurement. A July 2017 VA Examination showed flexion reduced to 100 degrees, including for consideration of pain, repetition, and flare-ups. Extension is not limited in any of the lay or medical records, so a rating for limitation of extension (Diagnostic Code 5261) is not warranted. Accordingly, a higher rating than 20 percent for the left knee disability under any alternative diagnostic code is not warranted. 3. Separate Rating for Slight Left Knee Instability from June 30, 2016 After a review of all the evidence, lay and medical, the lay and medical evidence is in equipoise as to whether there is slight left knee instability to warrant a separate 10 percent disability rating under Diagnostic Code 5257 for the entire rating period on appeal from June 30, 2016. There is lay and medical evidence that shows lay reports and findings of slight left knee instability but also shows an absence of findings of instability. An August 2016 VA Examination found that there was evidence of left knee joint instability, with a slight positive finding (1+) on a test of left knee anterior instability, although the left knee posterior instability, medial instability, and lateral instability tests were normal. A July 2017 VA Examination found that there was evidence of left knee joint instability, with a slight positive finding (1+) on tests of medial instability and lateral instability, with anterior instability and posterior instability tests normal. The Veteran has reported a history of some left knee instability, or reported symptoms consistent with instability, such as the knee giving way. A December 2016 letter from a private orthopedist, Dr. F., stated the Veteran's history of having experienced frequent left knee instability and giving way episodes since left knee surgery in 1987 or 1988, and a history of a left knee anterior cruciate ligament reconstruction surgery with patella tendon allograft and partial lateral meniscectomy in March 2016. At the July 2021 Board hearing, the Veteran testified that the left knee has never fully felt stable, and he has to be careful not to put too much stress on it. Resolving reasonable doubt in favor of the Veteran, and considering both lay and medical evidence, for the rating period on appeal from June 30, 2016, the Board finds criteria for a separate 10 percent disability rating for slight lateral left knee instability have been met. 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5257. (Continued on the next page) As for the degree of instability, the lay and medical evidence shows not more than slight left knee instability. Although the private orthopedist referred to frequent left knee instability, the testing demonstrates that the degree of impairment was slight (1+). The absence of findings of instability tends to show that, while instability is present, the barely detectable instability on clinical measure and testing is to only a slight degree. For these reasons, a separate 10 percent disability rating for left knee slight instability is granted. 38 C.F.R. §§ 4.3, 4.7, 4.71a, Diagnostic Code 5257. J. PARKER Veterans Law Judge Board of Veterans' Appeals Attorney for the Board A. Smith, 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.