Citation Nr: 21003583 Decision Date: 01/22/21 Archive Date: 01/22/21 DOCKET NO. 14-01 129 DATE: January 22, 2021 ORDER Entitlement to an increased rating greater than 10 percent for left knee degenerative arthritis is denied. Entitlement to a separate rating of 10 percent, but no higher, for left knee instability is granted. Prior to September 18, 2019, entitlement to an initial increased rating of 20 percent, but no higher, for right knee patellofemoral pain syndrome under Diagnostic Code 5258, is granted. The 10 percent initial rating for right knee patellofemoral pain syndrome under Diagnostic Code 5010-5260 prior to September 18, 2019 is discontinued. Entitlement to an increased initial rating of 30 percent, but no higher, for right knee patellofemoral syndrome from September 18, 2019 to September 24, 2020 is granted. Entitlement to an increased initial rating greater than 30 percent for right knee patellofemoral pain syndrome from September 25, 2020 is denied. Entitlement to an initial rating of 10 percent, but no higher, for right knee instability prior to September 25, 2020 is granted. Entitlement to an initial rating greater than 10 percent for right knee instability from September 25, 2020 is denied. REMANDED Entitlement to service connection for obstructive sleep apnea (OSA), to include as secondary to posttraumatic stress disorder (PTSD) with depression and traumatic brain injury (TBI), is remanded. FINDINGS OF FACT 1. The Veteran’s left knee degenerative arthritis exhibited painful, decreased range of motion but was not manifested by limitation of flexion to 45 degrees or less, or extension to 10 degrees or more. 2. The Veteran’s left knee degenerative arthritis was manifested by slight instability. 3. Prior to the Veteran’s meniscectomy and MCL reconstruction on September 18, 2019, the Veteran’s semilunar, dislocated cartilage of the right knee was manifest by frequent episodes of locking, pain, and effusion into the joint. 4. From September 18, 2019, the Veteran’s right knee condition was manifested by symptoms of functional loss equivalent to limitation of flexion to 15 degrees or less. 5. Throughout the appeal period, the Veteran’s right knee condition was manifested by slight instability. CONCLUSIONS OF LAW 1. The criteria for a disability rating greater than 10 percent for left knee degenerative arthritis have not been met. 38 U.S.C. §§ 1155, 5107 (2018); 38 C.F.R. §§ 3.655, 4.1, 4.3, 4.7, 4.71a, 20.608, 20.704, Diagnostic Code 5260-5010 (2020). 2. The criteria for a separate disability rating of 10 percent, but no higher, for left knee instability have been met. 38 U.S.C. §§ 1155, 5107 (2018); 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5257 (2020). 3. The criteria for an increased initial rating of 20 percent, but no higher, for a right knee condition prior to September 18, 2019 have been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107 (2018); 38 C.F.R. §§ 3.102, 3.159, 4.1, 4.3, 4.10, 4.14, 4.27, 4.40, 4.45, 4.59, 4.71a, Diagnostic Code 5258 (2020). 4. The criteria to discontinue the 10 percent initial rating for a right knee condition prior to September 18, 2019 under Diagnostic Code 5010-5260 have been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107 (2018); 38 C.F.R. §§ 3.102, 3.159, 4.1, 4.3, 4.10, 4.14, 4.27, 4.40, 4.45, 4.59, 4.71a, Diagnostic Codes 5010-5260, 5258 (2020). 5. The criteria for an increased disability rating of 30 percent, but no higher, for a right knee condition from September 18, 2019 to September 24, 2020 have been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107 (2018); 38 C.F.R. §§ 3.102, 3.159, 4.1, 4.3, 4.10, 4.14, 4.27, 4.40, 4.45, 4.59, 4.71a, Diagnostic Codes 5010-5260 (2020). 6. The criteria for a disability rating greater than 30 percent for a right knee condition from September 25, 2020 have not been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107 (2018); 38 C.F.R. §§ 3.102, 3.159, 4.1, 4.3, 4.10, 4.14, 4.27, 4.40, 4.45, 4.59, 4.71a, Diagnostic Codes 5010-5260 (2020). 7. The criteria for an initial disability rating of 10 percent, but no higher, for right knee instability prior to September 25, 2020 have been met. 38 U.S.C. §§ 1155, 5107 (2018); 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5257 (2020). 8. The criteria for an initial disability rating greater than 10 percent for right knee instability from September 25, 2020 have not been met. 38 U.S.C. §§ 1155, 5107 (2018); 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.71a, Diagnostic Code 5257 (2020). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from August 1991 to June 1997 and May 2005 to August 2006 with additional Reserve service. He appeals an April 2013 rating decision by the Department of Veterans Affairs (VA) Agency of Original Jurisdiction (AOJ) denying entitlement to service connection for OSA. Also before the Board of Veterans’ Appeals (Board) is the appeal of an August 2016 rating decision denying an initial rating greater than 10 percent for right knee patellofemoral pain syndrome and a rating greater than 10 percent for left knee degenerative arthritis. During the appeal period, the AOJ increased the Veteran’s right knee rating to 30 percent and found entitlement to a separate right knee instability rating of 10 percent, both effective September 25, 2020. After an April 2020 Board remand, these claims are now back before the Board. Disability ratings are determined by applying a schedule of ratings based on average impairment of earning capacity. Separate diagnostic codes identify the various disabilities. 38 U.S.C. § 1155; 38 C.F.R. Part 4. Each disability must be viewed in relation to its history and the limitation of activity imposed by the disabling condition should be emphasized. 38 C.F.R. § 4.1. When considering the propriety of the evaluation assigned, consideration of the medical evidence since the effective date of the award of service connection is required. See Fenderson v. West, 12 Vet. App. 199, 125-26 (1999). Where there is a question as to which of two evaluations shall be applied, the higher evaluation will be assigned if the disability picture more nearly approximates the criteria for that rating. Otherwise, the lower rating will be assigned. 38 C.F.R. § 4.7. Importantly, the evaluation of the same disability under various diagnoses is to be avoided. 38 C.F.R. § 4.14. However, when it is not possible to separate the effects of the service-connected disability from a nonservice-connected condition, such signs and symptoms must be attributed to the service-connected disability. See Mittleider v. West, 11 Vet. App. 181, 182 (1998); 38 C.F.R. § 3.102. The Veteran contends his left and right knee conditions are more severe than his current ratings indicate. The Veteran is currently service connected for left knee degenerative arthritis rated at 10 percent disabling and right knee patellofemoral pain syndrome rated at 10 percent prior to September 25, 2020 and 30 percent thereafter pursuant to 38 C.F.R. § 4.71a, Diagnostic Codes 5010-5260. See October 2020 rating decision codesheet. Additionally, the Veteran’s right knee instability was rated as 10 percent disabling effective September 25, 2020 under Diagnostic Code 5257. Id. Hyphenated diagnostic codes are used when a rating under one diagnostic code requires the use of an additional diagnostic code to identify the basis for the evaluation assigned; the additional code is shown after the hyphen. 38 C.F.R. § 4.27. Diagnostic Code 5010 provides that arthritis due to trauma is to be evaluated as degenerative arthritis pursuant to DC 5003. Diagnostic Code 5003 provides the criteria for rating disabilities that are due to degenerative arthritis. In instances where the loss of motion is non-compensable under the appropriate Diagnostic Code, a rating of 10 percent is assigned for each major joint or group of minor joints affected by the loss of motion. In the absence of any loss of motion, a 20 percent disability rating is assigned where there is x-ray evidence of involvement of two or more major joints with occasional incapacitating exacerbations. See 38 C.F.R. § 4.71a, Diagnostic Code 5003. The knee is considered a major joint. See 38 C.F.R. § 4.45. Here, the Veteran has degenerative arthritis in both knees. See October 2015 VA treatment records (“x-ray of both knees showed mild degenerative changes in February 2015”). Additionally, the record reflects the Veteran suffers from occasional incapacitating episodes. See, e.g., November 2017 and October 2019 VA examination reports (Veteran unable to perform examination due to incapacitating episodes). Accordingly, under this Diagnostic Code, the Veteran would be entitled to one rating of 20 percent for his bilateral knee conditions under Diagnostic Code 5010. Since the Veteran’s current ratings during the appeal period for each left and right knee condition is greater than one rating under Diagnostic Code 5010, the Board will analyze and rate the Veteran’s left and right knee condition under the specific rating criteria for knee disabilities. Knee disabilities are rated under Diagnostic Codes 5256 through 5263 of 38 C.F.R. § 4.71a. Diagnostic Code 5256 addresses ankylosis of the knee. Diagnostic Code 5257 addresses recurrent subluxation or lateral instability. Diagnostic Code 5258 addresses dislocated semilunar cartilage in the knee manifested by frequent episodes of “locking,” pain, and effusion into the joint. Diagnostic Code 5259 addresses symptomatic residuals related to removal of semilunar cartilage. Diagnostic Code 5260 addresses limitation of motion on flexion while Diagnostic Code 5261 addresses limitation of motion on extension. Diagnostic Code 5262 addresses impairment of the tibia and fibula from malunion or nonunion. Diagnostic Code 5263 addresses genu recurvatum. The Board must consider the Veteran’s service-connected bilateral knee conditions under each Diagnostic Code. Limitation of Motion Under Diagnostic Code 5260, a 10 percent disability rating is assigned where flexion of the leg is limited to 45 degrees. See 38 C.F.R. § 4.71a. A 20 percent disability rating is in order where leg flexion is limited to 30 degrees. Id. A maximum schedular 30 percent disability rating is assigned where leg flexion is limited to 15 degrees. Id. Similarly, Diagnostic Code 5261 provides ratings for limitation of extension with the following ratings assigned: 10 percent for limitation of extension to 10 degrees, 20 percent for limitation of extension to 15 degrees, 30 percent for limitation of extension to 20 degrees, 40 percent for limitation of extension to 30 degrees, and 50 percent for limitation of extension to 45 degrees. Id. For reference, normal range of motion for the knee is defined under the regulations as consisting of extension to zero degrees and flexion to 140 degrees. See 38 C.F.R. § 4.71, Plate II. When evaluating joint disabilities rated on the basis of limitation of motion, VA must consider granting a higher rating in cases in which functional loss due to pain, fatigue, weakness, or lack of endurance, incoordination, or flare-ups is demonstrated, and those factors are not contemplated in the relevant rating criteria. See DeLuca v. Brown, 8 Vet. App. 202, 204-07 (1995); see also 38 C.F.R. §§ 4.40, 4.45, 4.59. Thus, functional loss caused by pain must be rated at the same level as if the functional loss were caused by any of the other factors such as decreased or abnormal excursion, strength, speed, coordination, or endurance, as well as less or more movement than is normal, weakened movement, excess fatigability, and pain on movement. Mitchell v. Shinseki, 25 Vet. App. 32, 42-43 (2011). Therefore, in evaluating the severity of a joint disability, VA must determine the overall functional impairment due to these factors. Additionally, when there is evidence of painful motion, 38 C.F.R. § 4.59 operates to provide at least the minimum compensable rating available under the Diagnostic Code for the joint. See Sowers v. McDonald, 27 Vet. App. 472, 478 (2016). Left knee The Veteran is currently rated at 10 percent for limitation of motion. He is not entitled to the next highest rating, 20 percent, unless he exhibits limitation of flexion to 30 degrees or less, or extension limited to 15 degrees or more. In May 2015, the Veteran’s left knee flexion was limited to 125 degrees with pain on movement and full extension. See May 2015 VA examination report. During the course of the appeal, the Veteran’s left knee flexion ranged from a full range of motion (ROM) to a limitation of 90 degrees. See, e.g., July 2015 VA treatment records (full ROM both knees); December 2014 VA treatment records (“unable to assess ROM because Veteran resists flexion beyond 90 degrees”); June 2016 VA examination report (flexion to 90 degrees); November 2017 VA examination report (“exhibited about 1/3 of normal ROM” or 46.66 degrees); October 2019 VA examination report (130 degrees); September 2020 VA examination report (105 degrees). As such, the Veteran’s left knee condition is not compensable for VA benefits under Diagnostic Code 5260 and 5261 as an increased rating requires either flexion limited to 45 degrees or less, or, extension limited to 10 degrees or more. The Board must also consider whether a higher rating is warranted based on any additional functional loss. See DeLuca, 8 Vet. App. at 204-07; see also 38 C.F.R. §§ 4.40, 4.45, 4.59. Any evidence of functional loss during flare-ups or due to pain, weakness, fatigability, or incoordination that results in an equivalent limitation of motion of flexion limited to 30 degrees or less, or extension limited to 15 degrees or more would warrant a higher disability rating. The Veteran reported he cannot put any weight on his left knee during a flare-up and he has “throbbing pain that radiates up and down the knee” with a pain level of 10/10 that lasts anywhere from a few hours to days. See September 2020 VA examination report. He noted a “constant mild-moderate throbbing pain” with “occasional swelling with the weather changes.” Id. During flare-ups he also noted he can “barely drive” or “bend his knees.” See June 2016 VA examination report. However, the record does not reflect the Veteran experiences functional loss during flare-ups or due to pain that results in flexion limited to 30 degrees or less and the record reflects he has full extension of his left knee. For example, the June 2016 VA examination was conducted during a flare-up and the Veteran’s left knee range of motion was limited to 90 degrees. The September 2020 VA examiner found left knee flexion during a flare-up and with repeated use over time was reduced to 95 degrees due to pain. Thus, while the record reflects the Veteran’s left knee pain and flare-ups create additional functional loss, his left knee range of motion does not warrant a rating greater than 10 percent, even with functional loss during flare-ups and on repetition. Based on the entire record, the Board concludes the Veteran’s functional loss due to pain, repetitive use over time, and flare-ups does not warrant a greater disability rating for his left knee degenerative arthritis. See Mitchell, 25 Vet. App. at 42-43. His symptom picture more closely approximates his current 10 percent rating under Diagnostic Code 5260-5010 for painful motion. Also, the Veteran is not entitled to a compensable rating under Diagnostic Code 5261 as his left knee symptoms of pain and any functional loss are fully addressed under Diagnostic Code 5260. See Sowers, 27 Vet. App. at 478. Right knee prior to September 18, 2019 For the reasons below, the Board finds the Veteran’s symptom picture warrants a 20 percent disability rating under Diagnostic Code 5258 rather than a rating under Diagnostic Code 5010-5260, prior to September 18, 2019, the date of the Veteran’s meniscectomy and MCL reconstruction. The assignment of a particular diagnostic code is “completely dependent on the facts of a particular case.” See Butts v. Brown, 5 Vet. App. 532, 538 (1993). One diagnostic code may be more appropriate than another based on factors such as an individual’s relevant medical history and demonstrated symptomatology. Read v. Shinseki, 651 F.3d 1296, 1302 (2011). Furthermore, the selection of diagnostic codes or applicable rating criteria is not protected and may be appropriately revised if the action does not result in the reduction of compensation payments. See 38 C.F.R. §§ 3.951, 3.957; Butts, 5 Vet. App. 532. The Board notes that the Veteran’s 10 percent rating under Diagnostic Code 5010-5260 has been in effect since May 2016; hence, the rating is not a protected disability rating. See Murray v. Shinseki, 24 Vet. App. 420, 428 (2011) (a rating is protected if it has been in effect for twenty years). Moreover, this change in diagnostic codes does not amount to a reduction, as the rating of the Veteran’s right knee disability, without considering instability, increases from 10 percent to 20 percent, prior to September 18, 2019, pursuant to the Order above. Under Diagnostic Code 5258, limitation of motion is reflected by symptoms of pain, locking, and effusion. See 38 C.F.R. § 4.71a. Under Diagnostic Codes 5260 and 5261, such limitation of motion is encompassed by the limitation of flexion and extension, including limitation of motion due to pain. Id. Both diagnostic codes overlap in “locking” as a form of limitation of motion that is usually accompanied by pain; therefore, the diagnostic codes both rate on knee pain and limitation of motion due to pain. Id. Prior to September 18, 2019, the Veteran had full extension and his most limited flexion was recorded at 46.66 degrees. See June 2016 VA examination report (flexion to 90 degrees); November 2017 VA examination report (“exhibited about 1/3 of normal range of motion”). As such, the Veteran’s right knee disability was not compensable for VA benefits under Diagnostic Code 5260 and 5261 as his flexion was not limited to 45 degrees or less and he had full extension. However, when there is evidence of painful motion, 38 C.F.R. § 4.59 operates to provide at least the minimum compensable rating available under the Diagnostic Code for the joint. See Sowers, 27 Vet. App. at 478. Here, the Veteran reported pain and flare-ups caused by physical activity, or movement. See June 2016 VA examination report. As such, the Veteran’s right knee pain entitled him to a minimum disability rating under Diagnostic Code 5260, or 10 percent. He would not be entitled to a rating greater than 20 percent under Diagnostic Code 5010-5260 as the next highest rating would require flexion limited to 30 degrees or the equivalent functional loss due to pain, fatigue, weakness, or lack of endurance, incoordination, or flare-ups. See DeLuca, 8 Vet. App. at 204-07. In this case, the medical and lay evidence reflects the Veteran did not experience functional loss due to weakness, lack of endurance, or fatiguability. See June 2016 and November 2017 VA examination reports. In fact, the June 2016 VA examination was conducted during a flare-up and the VA examiner noted any functional loss during flare-ups and with repeated use over time was due to pain and reflected flexion limited to 90 degrees. Id. Thus, under Diagnostic Codes 5260 and 5261, the Veteran is not entitled to a higher rating than 10 percent prior to September 18, 2019. However, the evidence during this period of the appeal reflects his main symptoms included frequent episodes of locking, swelling, and pain. The Veteran filed his claim for a right knee condition in May 2016. See May 2016 VA Form VA For, 21-526EZ. One month prior, MRI imaging results revealed the Veteran had a “complex tear involving the posterior horn of the medial meniscus extending to both the superior and inferior articular surfaces” with a “3mm loose body” located in the medial joint fluid. See April 2016 VA treatment records. The Veteran reported swelling, recurrent pain, and that his right knee “hurt so bad that he [could not] walk up or down stairs without help.” Id.; see also June 2016 VA examination report. He also reported he could “feel the loose body” and had “intermittent mechanical symptoms of catching and locking.” See November 2016 and December 2016 VA treatment records. In February 2017, the Veteran’s physician noted his symptoms were worse. See February 2017 VA treatment records. Diagnostic Code 5258 provides a distinct 20 percent rating for such symptoms. See 38 C.F.R. § 4.71a. This is the highest disability rating under Diagnostic Code 5258 and affords the Veteran a higher rating than his current rating under Diagnostic Code 5010-5260. Id. Thus, the Board finds Diagnostic Code 5258 better encompasses the Veteran’s symptoms than Diagnostic Code 5010-5260, prior to September 18, 2019. The predicate element in assigning several ratings under various diagnostic codes is that none of the symptomatology for any one of the disabilities is duplicative or overlapping with the symptomatology of the other disability. See Esteban v. Brown, 6 Vet. App. 259, 261-62 (1994). Were the Board to grant separate ratings under Diagnostic Codes 5258, 5260, and 5261, the Veteran would receive compensation under three different codes for the same manifestations of pain and limitation of motion, which would constitute impermissible pyramiding. See 38 C.F.R. § 4.14. Accordingly, the Board finds that a 20 percent rating under Diagnostic Code 5258 is warranted as it is more favorable to the Veteran, and the 10 percent rating under Diagnostic Code 5010-5260 is discontinued prior to September 18, 2019. Right knee from September 18, 2019 Although the Board has changed the Veteran’s Diagnostic Code for his service-connected right knee prior to September 18, 2019, this change is not warranted for the period on appeal from September 18, 2019, which is after his MCL reconstruction and meniscectomy. As stated above, Diagnostic Code 5258 mandates that limitation of motion is reflected by dislocated lunar cartilage in conjunction with the symptoms or findings of frequent episodes of locking, pain, and effusion into the joint. See 38 C.F.R. § 4.71a Diagnostic Code 5258. After the Veteran’s surgery, the record no longer reflects a dislocated meniscus with a symptom picture with frequent pain, effusion, and locking. For example, the Veteran reported severe pain and “constant swelling” at his September 2020 VA examination but denied episodes of locking. See September 2020 VA examination report. At a physical therapy consultation, the Veteran noted symptoms of pain and swelling, but no locking. See February 2020 VA treatment records. In aggregate, the Veteran’s record on appeal after September 18, 2019 does not reflect he suffers from frequent episodes of locking. Accordingly, the Veteran’s original Diagnostic Code 5010-5260 is continued from September 18, 2019. In October 2019, the Veteran was afforded a VA examination to assess the severity of his right knee condition; however, testing was not completed because the Veteran was three weeks post-meniscectomy and MCL reconstruction. February 2020 VA treatment records reflect the Veteran’s right knee flexion was limited to 90 degrees and the physical therapist concluded the Veteran had moderate functional limitations at that consultation. The next examination occurred in September 2020, during which the Veteran was suffering a flare-up and the VA examiner was not able to adequately measure the Veteran’s right knee movement. See September 2020 VA examination report. The VA examiner noted the Veteran “was unable to flex his right knee even when going from sitting to standing [and] he used his left knee to stand up from [the] chair.” Id. The Veteran stated his flare-ups include 10/10 throbbing pain “that radiates up and down the knee” and he “can’t put any weight on it” occurring anywhere from a few hours to a few days. Id. Additionally, the VA examiner estimated the Veteran’s pain during flare-ups resulted in the functional loss equivalent of flexion limited to 10 degrees. Id. With repetitive use over time, the VA examiner further estimated right knee flexion would reduce to 5 degrees. Id. After this examination, the AOJ increased the Veteran’s right knee disability rating to 30 percent, effective the date of the examination, September 25, 2020. However, as noted above, there is no evidence of record that these symptoms during flare-ups did not exist prior to the September 2020 examination. As such, affording the Veteran the benefit of the doubt, the Board finds he is entitled to a 30 percent rating, from September 18, 2019 the date of the Veteran’s meniscectomy and MCL reconstruction. This is the highest rating allowed under Diagnostic Code 5260. Additionally, the Veteran is not entitled to a compensable rating under Diagnostic Code 5261 as his right knee symptoms of pain and any functional loss are fully addressed under Diagnostic Code 5260 and the record reflects he has full extension from September 18, 2019. Instability Diagnostic Code 5257 provides ratings for demonstrated knee joint instability with the following ratings assigned: 10 percent for slight, 20 percent for moderate, and 30 percent for severe, recurrent subluxation or lateral instability. 38 C.F.R. § 4.71a, Diagnostic Code 5257. The words “slight,” “moderate,” and “severe” as used in the various diagnostic codes are not defined in the VA Rating Schedule. Rather than applying a mechanical formula, the Board must evaluate all the evidence, to the end that its decisions are “equitable and just.” See 38 C.F.R. § 4.6. “Nothing in DC 5257 provides that objective medical evidence is required or is to be favored over lay evidence.” See English v. Wilkie, 30 Vet. App. 347, 352-53 (2018). Although no VA examiner during the appeal period found left knee instability or laxity during examination testing, the Veteran reported both left and right knee instability. Additionally, the record reflects the Veteran suffered slight instability of both knees during the appeal period. In October 2015, the Veteran noted his “knees have become unstable” and in December 2016 he reported to have fallen and “hurt both his knees.” See October 2015 and December 2016 VA treatment records. In January 2016, the Veteran noted his right knee gave out. See January 2016 VA treatment records. During a physical therapy evaluation, the Veteran reported “fear of falling” during single leg squats. See February 2020 VA treatment records. The record also reflects the Veteran has regularly used either a brace or cane during the appeal period for support to both knees. See, e.g., March 2016 VA treatment records (hinged knee braces); August 2017 VA treatment records (fitted for knee braces); November 2017 VA examination report (regular use of brace on both knees “for the diagnosed condition”); October 2019 VA examination report (regular use of brace and cane “for right knee arthritis”). Thus, the Board finds the Veteran’s symptoms more closely reflect slight instability and he is entitled to a 10 percent rating for each left and right knee instability during the entire appeal period. However, his symptoms do not reflect a more severe rating for symptoms reflecting moderate instability. Numerous VA examiners did not find instability in testing and although the record reflects a couple instances of falling, the Veteran also reported “no falls in the past 12 months” on numerous occasions. See July 2017 VA examination report (fell June 2017); see also October 2017 (“no falls in the past 12 months”). As such, the Board grants a separate 10 percent rating for left knee instability. The Board also grants a 10 percent initial disability rating for right knee instability prior to September 25, 2020 and denies a rating greater than 10 percent from September 25, 2020. Other Diagnostic Codes For the right knee, after the Veteran’s meniscectomy and MCL reconstruction, he still experiences symptoms of pain and effusion, as discussed above. Therefore, he could be entitled to a separate disability rating under Diagnostic Code 5259 from September 18, 2019. However, the Veteran’s reported symptoms from September 18, 2019 are fully considered in his 30 percent rating for limitation of flexion due to pain and flare-ups under Diagnostic Code 5010-5260. Assigning an additional, separate rating would violate the rules prohibiting pyramiding as it would compensate the Veteran twice for the same symptomatology of pain. 38 C.F.R. § 4.14. Prior to September 18, 2019, Diagnostic Code 5259 also does not apply as the Veteran still had his right knee semilunar cartilage. For the left knee, the Veteran does not have a meniscus condition. Hence, separate disability ratings under Diagnostic Codes 5258 or 5259 are not applicable. Further, the evidentiary record does not suggest impairment of tibia and fibula or genu recurvatum in either knee. As such, separate disability ratings under Diagnostic Codes 5262 and 5263 are not warranted. Also, the Veteran has not exhibited ankylosis; hence, a separate rating under Diagnostic Code 5256 is also not warranted. Accordingly, all potentially applicable Diagnostic Codes have now been considered. See Schafrath v. Derwinski, 1 Vet. App. 589, 593 (1991). In summation, the Board denies an increased rating greater than 10 percent for left knee degenerative arthritis but grants entitlement to a separate rating of 10 percent, but no higher, for left knee instability. For the right knee, the Board finds the evidence more closely approximates the criteria for a 20 percent rating prior to September 18, 2019 under Diagnostic Code 5258, and a 30 percent rating from September 18, 2019 under Diagnostic Code 5010-5260. The Board also finds the Veteran is entitled to an initial disability rating of 10 percent, but no higher, for right knee instability. Finally, the right knee rating under Diagnostic Code 5010-5260 is discontinued prior to September 18, 2019. REASONS FOR REMAND The Board has remanded the issue of entitlement to service connection for OSA no fewer than four times. Most recently, in April 2020, the Board found all prior opinions inadequate and remanded to obtain an opinion on whether the Veteran’s current sleep apnea, medically diagnosed in March 2012, started with reported symptoms in service or whether it was caused or aggravated by his service-connected PTSD with depression and TBI. The April 2020 Board remand specifically stated the reviewing clinician “must address the Veteran’s submitted medical literature.” Unfortunately, this was not done. Instead, the reviewing clinician provided boilerplate rationale for each Board remand directive regarding secondary service connection. See September 2020 VA opinion. The reviewing clinician noted “obstructive sleep apnea is an anatomical condition” and concluded that “while some studies have shown that OSA and [PTSD/TBI] can co-exist there is no credible medical evidence [of a causative link/to support the notion that the anatomical condition can be aggravated by PTSD/TBI]. The Veteran’s complaints of fatigue and sleep disruption are not pathognomonic for obstructive sleep apnea, and alone are not diagnostic criteria. OSA can only be diagnosed by polysomnography, which was not completed until March 2012. A nexus is not established.” Id. This opinion states there is “no credible medical evidence,” but failed to address the credible medical evidence provided by the Veteran. For PTSD, the Veteran’s May 2016 appellate brief included excerpts from a medical study by the American Academy of Sleep Medicine which found “the probability of having a high risk of OSA increased with increasing severity of PTSD.” See May 2016 appellate brief. Some 69.2 percent of participants with PTSD in the study had a high risk for sleep apnea, and this risk increased with PTSD symptom severity. Id. The Veteran submitted other medical evidence, including a statement from Dr. S.P., who noted “54 percent of PTSD patients who underwent formal sleep studies were found to have OSA. This is much higher than what’s normally expected (about 20% percent)…it’s likely that they always had some degree of obstructive sleep apnea to begin with, and once the emotional or physical trauma took place, memories or thoughts of that event can trigger a hyperintense reaction, since [their] nervous system is going to be hypersensitive in general.” See May 2016 appellate brief. For TBI, the Veteran submitted a medical study published in the Journal of Rehabilitation Research and Development that noted “initial studies suggest [sleep apnea] is associated with cognitive impairments” among patients with TBIs. Id. Recent studies found a specific allele, often found in TBI patients, increased the risk for sleep disordered breathing, particularly sleep apnea. Id. Finally, the Veteran submitted additional medical evidence supporting his contentions in a subsequent February 2018 appellate brief. None of the aforementioned medical evidence was discussed by the reviewing clinician. Instead, she provided a definition of sleep apnea and stated there was no competent medical evidence to show OSA is caused or aggravated by PTSD or TBIs. See September 2020 VA opinion. Thus, a remand is required to fully address the plethora of medical evidence provided by the Veteran. The matters are REMANDED for the following action: 1. Obtain any updated relevant VA and/or private treatment records that have not already been obtained and associate the same with the claims file. 2. Thereafter, obtain an opinion from an appropriately qualified clinician, other than the clinician who provided the September 2020 opinion, to determine the relationship between the Veteran’s OSA and his service-connected PTSD with depression and TBI. The evidentiary record, including a copy of this remand, must be made available to and reviewed by the reviewing clinician. It is up to the discretion of the reviewing clinician whether a new examination is necessary to provide an adequate opinion. After a thorough review of the record, the reviewing clinician should answer the following: (a). Is it at least as likely as not (a 50 percent probability or more) the Veteran’s OSA began in service, or is otherwise related to service? The reviewing clinician is directed to address the May 2015 American Academy of Sleep Medicine article submitted in the February 2018 appellate brief noting “younger veterans with PTSD are rarely screened for sleep apnea and frequently remain undiagnosed…the mechanism underlying the relationship between sleep apnea and PTSD in military veterans is unclear. However, potential factors that may connect the two disorders include disturbed sleep in combat, prolonged sleep deprivation, sleep fragmentation and hyperarousal due to the physical and psychological stressors of combat, the chronic stress from PTSD, or the sleep disturbances caused by OSA.” The reviewing clinician is further directed to the Veteran’s lay statements, including but not limited to, (1) April 2014 Appellate brief statement that his continued in-service complaints of sinus congestion at night are related to his sleep apnea, and (2) August 2011 VA psychiatric examination report noting the Veteran “had trouble sleeping for 5 years…wakes up two or three times at night…not rested each day.” (b). Is it at least as likely as not (a 50 percent probability or more) that the Veteran’s OSA was (1) caused or (2) aggravated by his service-connected PTSD with depression? The reviewing clinician must address the medical evidence provided in the May 2016 and February 2018 appellate briefs, including, but not limited to: (1) the May 2015 American Academy of Sleep Medicine study which found “the probability of having a high risk of OSA increased with increasing severity of PTSD…” 69.2 percent of participants in the study had a high risk for sleep apnea, and this risk increased with PTSD symptom severity; (2) Dr. S.P. statement noting “54 percent of PTSD patients who underwent formal sleep studies were found to have OSA. This is much higher than what’s normally expected (about 20% percent)…it’s likely that they always had some degree of obstructive sleep apnea to begin with, and once the emotional or physical trauma took place, memories or thoughts of that event can trigger a hyperintense reaction, since your nervous system is going to be hypersensitive in general;” and (3) the December 2011 European Journal of Psychotraumatology and May 2015 Journal of Clinical Sleep Medicine studies concluding “PTSD severity was related to OSA” and “PTSD symptom severity increased risk of screening positive for snoring and fatigue.” (c). Is it at least as likely as not (a 50 percent probability or more) that the Veteran’s OSA was (1) caused or (2) aggravated by his service-connected TBI? The reviewing clinician must to address the medical evidence provided in the May 2016 and February 2018 Appellate Briefs, including, but not limited to the following: (1) 2009 study in the Journal of Rehabilitation Research and Development noted “initial studies suggest [sleep apnea] is associated with cognitive impairments” among patients with TBIs. Recent studies found a specific allele, often in patients with TBIs, increased the risk for sleep disordered breathing, particularly sleep apnea; (2) February 2016 Neuropsychiatric Disease and Treatment article concluding “sleep disorders are prevalent in patients following TBI;” (3) November 2012 Neuropsychiatric Disease and Treatment article noting “sleep disturbances are frequently identified following TBI” including sleep apnea…“in addition, depression, anxiety, and pain are common brain injury comorbidities with significant influence on sleep quality…treatment of sleep disorders associated with TBI may not improve neuropsychological function or sleepiness.” (d). Is it at least as likely as not (a 50 percent probability or more) that the Veteran’s OSA was (1) caused or (2) aggravated by the combination of his service-connected PTSD with depression with TBI? A full and complete rationale for all opinions must be provided, and a discussion of the facts and medical principles involved would be of considerable assistance to the Board. If the reviewing clinician cannot provide a requested opinion without resorting to mere speculation, it must be stated, and the reviewing clinician must provide the reasons why an opinion would require speculation. As such, the reviewing clinician must explain whether the inability to provide a more definitive opinion is the result of a need for additional information, or that he or she has exhausted the limits of current medical knowledge in providing an answer to that particular question. 3. Thereafter, readjudicate the claim. If any benefit sought remains denied, provide the Veteran and his representative with a Supplemental Statement of the Case (SSOC) and return the case to the Board. DONNIE R. HACHEY Veterans Law Judge Board of Veterans’ Appeals Attorney for the Board J. Bona, 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.