Citation Nr: 21077178 Decision Date: 12/28/21 Archive Date: 12/28/21 DOCKET NO. 17-39 550 DATE: December 28, 2021 ORDER 1. A 30 percent combined (10 percent under Diagnostic Code (Code) 5257, 10 percent under Code 5259, and 10 percent under Codes 5003-5260) rating is granted for the Veteran's pre-total knee replacement (TKR) left knee disability from June 8, 2014 to September 12, 2017, subject to the regulations governing payment of monetary awards; entitlement to a combined rating in excess of 50 percent from September 12, 2017 to October 19, 2020 is denied. REMANDED 2. Entitlement to a combined rating in excess of 50 percent from December 1, 2021, for the Veteran's (now post-TKR) left knee disability is remanded. FINDINGS OF FACT 1. From June 8, 2014 (one year prior to the June 8, 2015 date of claim for increase) to September 12, 2017, the Veteran's pre-TKR left knee disability is reasonably shown to have been manifested by arthritis with complaints of pain, stiffness, noncompensable limitation of flexion, slight (but not greater) instability, and symptomatic post-removal of semilunar cartilage; it is not shown to have been manifested by ankylosis, dislocated semilunar cartilage, compensable limitation of knee extension, impairment of tibia and fibula, or genu recurvatum. 2. From September 12, 2017 to October 19, 2020 (the date of his left TKR surgery), the Veteran's left knee disability is reasonably shown to have been manifested by flexion limited to, at worst, 60 degrees and extension limited at 32 degrees, slight (but not greater) instability, and symptomatic post-removal of semilunar cartilage; it is not shown to have been manifested by ankylosis, dislocated semilunar cartilage, impairment of tibia and fibula, or genu recurvatum. CONCLUSION OF LAW A staged increased combined (to 30 percent, but not higher, based on a formulation of 10 percent under Code 5257, 10 percent under Code 5259, and 10 percent under Codes 5003-5260) rating is warranted from (the earlier date of) June 8, 2014 to September 12, 2017 for the Veteran's left knee disability; a (combined) rating in excess of 50 percent from September 12, 2017 to October 19, 2020 is not warranted. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.10, 4.14, 4.21, 4.25, 4.40, 4.45, 4.59, 4.71a; Codes 5003, 5256-5263. REASONS AND BASES FOR FINDINGS AND CONCLUSION The appellant is a Veteran who served on active duty from February 1992 to May 1998. This matter is before the Board of Veterans' Appeals (Board) on appeal from an October 2015 rating decision, which granted service connection for left knee anterior cruciate ligament (ACL) reconstruction and meniscectomy with osteoarthritis (under Code 5261), and continued a 10 percent rating for left knee anterior instability (under Code 5257)). In May 2016, the Board remanded the matter for issuance of a Statement of the Case (SOC) pursuant to Manlincon v. West, 12 Vet. App. 238 (1999). An interim (September 2018) rating decision increased the rating for left ACL reconstruction and meniscectomy with osteoarthritis from 10 to 40 percent, effective September 12, 2017. In September 2019, a hearing was held before the undersigned in Washington, D.C.; a transcript is in the Veteran's record. In September 2020 and May 2021, the case was remanded for additional development. A December 2020 rating decision, inter alia, assigned a total (schedular post-TKR) rating from October 19, 2020 to December 1, 2021. Therefore, that period is not for consideration. 1. An increased combined (to 30 percent) rating is granted from (the earlier date of) June 8, 2014 to September 12, 2017 for the Veteran's pre-TKR left knee disability; entitlement to a combined rating in excess of 50 percent from September 12, 2017 to October 19, 2020 is denied. Legal Criteria Disability evaluations are determined by the application of a schedule of ratings, which is based on average impairment of earning capacity caused by the given disability. Separate diagnostic codes identify the various disabilities. 38 U.S.C. § 1155; 38 C.F.R. Part 4. Where entitlement to compensation has already been established and increase in disability is at issue, the present level of disability is of primary concern. See Francisco v. Brown, 7 Vet. App. 55 (1994). "Staged" ratings may be warranted where the factual findings show distinct time periods when the service-connected disability exhibits symptoms that would warrant different ratings. See Hart v. Mansfield, 21 Vet. App. 505 (2007). When a question arises as to which of two ratings applies under a particular code, the higher rating is assigned if the disability more closely approximates the criteria for the higher rating. 38 C.F.R. § 4.7. After careful consideration of the evidence, any reasonable doubt remaining, including regarding degree of disability, is resolved in favor of the Veteran. 38 U.S.C. § 5107; 38 C.F.R. §§ 3.102, 4.3. The criteria for rating knee disabilities are found at 38 C.F.R. § 4.71a, Codes 5256-5263. Code 5256 applies when the knee is ankylosed. Under Code 5257, knee impairment manifested by recurrent subluxation or lateral instability is rated 10 percent when slight, 20 percent when moderate, and 30 percent (the maximum) when severe. Under Code 5258, a maximum 20 percent rating is warranted for dislocation of semilunar cartilage with frequent episodes of "locking," pain, and effusion into the joint. Under Code 5259, a 10 percent rating is assigned for symptomatic removal of semilunar cartilage. Under Code 5260, limitation of flexion of the leg warrants a 0 percent rating when flexion is limited to 60 degrees; a 10 percent rating when limited to 45 degrees; a 20 percent rating when limited to 30 degrees; and a (maximum) 30 percent rating when limited to 15 degrees. Under Code 5261, limitation of extension of the leg warrants a 0 percent rating when extension is limited at 5 degrees; a 10 percent rating when limited at 10 degrees; a 20 percent rating when limited at 15 degrees; a 30 percent rating when limited at 20 degrees; a 40 percent rating when limited at 30 degrees; and a (maximum) 50 percent rating when limited at 45 degrees. Normal or full range of motion (ROM) of the knee is from 0 degrees of extension to 140 degrees of flexion. Plate II. 38 C.F.R. § 4.71. Code 5262 applies when there is malunion or nonunion of the tibia and fibula. Code 5263 applies when there is acquired, traumatic genua recurvatum. Degenerative arthritis established by X-ray findings is rated on the basis of limitation of motion under the appropriate Code(s) for the specific joint(s) involved. When the limitation of motion is noncompensable under the appropriate Code(s), a 10 percent rating is for application for each such major joint affected by limitation of motion, to be combined, not added under Code 5003. Limitation of motion must be objectively confirmed by findings such as swelling, muscle spasm, or satisfactory evidence of painful motion. 38 C.F.R. § 4.71a, Code 5003. Separate ratings may be assigned for separate symptoms, including for [compensable] limitations of flexion and extension, instability, and dislocation of semilunar cartilage or symptomatic removal of semilunar cartilage. VAOPGCPREC 9-2004 (September 17, 2004), 69 Fed. Reg. 59990 (2004). In determining the degree of limitation of motion, the provisions of 38 U.S.C. §§ 4.10, 4.40, and 4.45 are for consideration. See DeLuca v. Brown, 8 Vet. App. 202 (1995). The basis of disability evaluation 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. Disability of the musculoskeletal system is primarily the inability, due to damage or infection in parts of the system, to perform the normal working movements of the body with normal excursion, strength, speed, coordination, and endurance. Functional loss may be due to the absence or deformity of structures or other pathology, or it may be due to pain, supported by adequate pathology and evidenced by the visible behavior in undertaking the motion. Weakness is as important as limitation of motion, and a part that becomes painful on use must be regarded as seriously disabled. 38 C.F.R. § 4.40. With respect to joints, in particular, the factors of disability reside in reductions of normal excursion of movements in different planes. Inquiry will be directed to more or less than normal movement, weakened movement, excess fatigability, incoordination, pain on movement, swelling, deformity or atrophy of disuse. 38 C.F.R. § 4.45. An increased rating may be assigned for up to one year prior to receipt of a formal claim for increase, when it is factually ascertainable that an increase in disability had occurred during that period. 38 C.F.R. §§ 3.157, 3.400(o)(2). Consequently, the evaluation period for consideration here is from June 2014 (a year prior to the June 8, 2015 date of claim). [The Board notes that the schedular criteria for evaluating disabilities of the musculoskeletal system, including the knee joint, were revised during the pendency of this appeal. Specifically, and as relevant to this case, revisions to Codes 5055 and 5257 were made effective February 7, 2021. See 85 Fed. Reg. 76460, 76457 (Feb 7, 2021). However, application of the new criteria prior to the effective date of the amended regulation is not allowed. See Kuzma v. Principi, 341 F.3d 1327 (Fed. Cir. 2003); Green v. Brown, 10 Vet. App. 111, 116-119 (1997); see also 38 U.S.C. § 5110(g). As the Board herein is adjudicating the matter of the rating prior to October 19, 2020, and the period from October 19, 2020 to December 1, 2021 (when a total (convalescence and schedular) rating has been assigned) is not for consideration, the Board will not address the new (revised) regulations herein. They may be for consideration on remand.] Factual Background A January 2014 (several months prior to the period for consideration) VA treatment record notes the Veteran's complaint of left knee swelling, popping, and grinding. He denied locking, but reported "occasional buckling." The Veteran reported that he walks on a treadmill for exercise and works as an engineer "in the field." Examination showed no effusion, mild medial and lateral facet tenderness, negative McMurray test, and stable ligaments except for 1+ Lachman test. The assessment was tricompartmental osteoarthritis of the left knee. On August 2015 VA (fee basis) knee examination (by an occupational medicine physician), the diagnoses were left knee degenerative arthritis and left ACL reconstruction and meniscectomy. The Veteran reported that his meniscus was removed in 1995 "as it was locking up his knee and shortly thereafter he had an ACL reconstruction done." He reported that he was told he has arthritis and might need a TKR soon. He reported flare-ups manifested by swelling and pain during certain activities, and that he cannot run, his knee limits walking, and he has marked difficulty with kneeling and squatting. Examination found that left knee ROM was from 0 to 95 degrees. There was objective evidence of crepitus, but no evidence of localized tenderness or pain on palpation of the joint. Repetitive use testing did not result in additional loss of function or ROM. The examiner found the examination consistent with the Veteran's statements describing functional loss with repeated use over time and during flare-ups, and noted that pain would significantly limit functional ability during those periods, acknowledging the Veteran's reports of difficulty traversing stairs, kneeling, squatting, and prolonged walking. Muscle strength testing was 5/5 on flexion and extension. There was no muscle atrophy or ankylosis. There was no history of recurrent subluxation or lateral instability. Joint stability testing showed anterior instability was 1+ (0-5 millimeters); posterior, medial, and lateral stability were normal. There were no shin splints or any other tibial or fibular impairment. The examiner noted the Veteran's report of a prior meniscal tear and that he "had the meniscus removed as the initial surgery." He noted that residuals of the meniscectomy and ACL repair include chronic pain and decreased ROM. He noted regular use of a brace "to help with pain and stability." There was not functional impairment such that no effective function remains other than that which would be equally served by an amputation with prosthesis. X-rays showed arthritis. The examiner opined that the left knee disability impacts the Veteran's ability to work because he has difficulty squatting, kneeling, traversing stairs and ladders, and walking more than one mile. An October 2015 rating decision continued a 10 percent rating for left knee instability and granted service connection for left knee ACL reconstruction and meniscectomy with osteoarthritis, rated 10 percent (under Codes 5003-5260) effective June 8, 2015. See October 2015 codesheet. In a November 2015 notice of disagreement (NOD), the Veteran disagreed with the new 10 percent rating assigned (for a combined 20 percent rating) and requested a 30 percent rating (for a combined 40 percent rating) based on limitation of extension. He reported that a "VA doctor ordered a special brace for my knee to help with Extension." He also reported that he was scheduled for additional knee injections, and that without the brace and medication, he would not be able to extend or flex his knee as much as he can due to "unbearable pain." He reported that he had "part of my meniscus tak[en] out also," and that he has been told a knee replacement is the next step due to his deteriorating knee. A November 29, 2016 VA treatment record notes a complaint of progressive left knee pain, and a notation that the Veteran "has developed severe osteoarthritis." The Veteran removed his brace for examination, which showed "moderate swelling," diffuse tenderness, and no signs of infection. ROM was "0-100?" There was no evidence of instability. X-ray showed "Progression of moderate to moderately severe tricompartmental degenerative changes, with mild lateral subluxation of tibia with respect to femur." He was given a gel-one knee injection. A September 12, 2017 VA treatment record notes the Veteran's complaint of bilateral knee pain, and his report of limited activities due to fear of his knee giving way. Examination showed stable gait on a flat surface; there was swelling in the left thigh and leg; left leg motor strength was weaker than the right leg "which has better muscle tone." ROM testing showed "left knee -32? (knee flexion contracture) and 67? maximum knee flexion." The clinician noted "bone-on-bone arthritis medial compartment compared to more normal appearance of right knee joint articular cartilage." The impression was "Advanced posttraumatic arthrosis left knee." The Veteran received a steroid injection. The clinician noted, "Ultimately he will need a total knee replacement." In a statement received in October 2017, the Veteran expressed disagreement with the lack of compensation for "the Partial Meniscus in my knee that was removed due to the Partial Bucket tear." A September 2018 VA treatment record notes the Veteran's complaint of left knee pain and instability. He reported that he wears a left knee brace daily to prevent hyperextension due to residual multi-directional instability. He reported he is currently working, but at a "sitdown job" due to his left knee disability. Examination found ROM noted as "-32 degrees to 67 degrees." The left knee was "loose to varus and valgus stress and some to the anterior posterior stress as well... He walks with his brace to stabilize his loose knee joint." The impression was posttraumatic left knee arthritis with multidirectional instability and limited ROM. On April 2019 VA (fee basis) knee examination (by a family medicine physician), the diagnoses were left knee strain and left knee ACL reconstruction and meniscectomy with osteoarthritis and anterior instability. The Veteran reported flare-ups manifested by extreme pain rated 9/10, from 2016 to present. He reported that he has to use knee braces, that he has difficulty walking, that the pain affects his sleep, and that his left knee disability is affected by weather and prolonged standing/walking. Initial ROM testing showed flexion to 90 degrees and extension to 0 degrees. Pain was noted on flexion and extension but did not cause functional loss. There was objective evidence of tenderness or pain on palpation to the anterior/lateral knee. There was no evidence of pain with weight-bearing or of crepitus. Repetitive use testing did not result in additional loss of function or ROM. The examiner found no other factors that contributed to the disability, and opined that on repeated use over time and during flare-ups, the left knee would experience pain and fatigue, and that ROM would be limited from 0 to 80 degrees. Muscle strength testing was normal (5/5). There was no muscle atrophy or ankylosis. There was no history of recurrent subluxation, lateral instability, or recurrent effusion. Joint stability testing showed anterior instability was 1+ (0-5 millimeters); posterior instability was 1+; medial and lateral stability were normal. There were no shin splints, other tibial or fibular impairment, or genu recurvatum. The examiner noted a prior meniscal tear that was treated surgically; he noted that the "Veteran has pain in the knee joint and it locks up when walking." The ACL surgery residuals include scars and limitation of motion. Constant use of bilateral knee braces was noted. There was not functional impairment such that no effective function remains other than that which would be equally served by an amputation with prosthesis. September 2018 x-rays showed tricompartmental osteoarthritis. The examiner opined that the left knee disability impacts the Veteran's ability to work because he cannot walk more than one block. At the September 2019 Board hearing, the Veteran testified that he began receiving left knee steroid injections in 2014 or 2015, when he noticed "the knee was worse and the arthritis in it and everything." He related that doctors ordered a new knee brace for instability for him. He testified that in 2015 or 2016 he was told he would need a TKR. He testified his symptoms in 2015 were the same as those recorded in 2017. He testified that his knee "would give out at times" in 2015, and that his ROM in 2014 or 2015 was limited [in extent] similar to that noted in 2017. He explained that his doctor advised him to wait until he was a little older to proceed with the knee replacement. Upon questioning from the undersigned, the Veteran testified that he had arthritis shown on 2014 x-rays, and that he had locking of the knee (noting a meniscectomy in 1995 or 1996) prior to 2017. On March 2020 VA (fee basis) knee examination (by a general medicine physician), the diagnoses were left knee degenerative arthritis and status post ACL reconstruction and meniscectomy. The Veteran reported symptoms including weakness, limitation of motion, stiffness, and instability, treated with a brace, pain medication, topical ointment, and therapy. He reported left knee flare-ups that occur every day, are "severe" in nature, last "all day every day...as soon as I get up in the morning and start walking." He reported that with repeated use over time he experiences severe instability, severe pain, weakness, and "can't bend." He stated that no treatment helps, and that he plans to see a specialist to schedule a TKR surgery. Initial ROM testing showed left knee ROM was 5 to 70 degrees. Pain was noted on flexion and extension to cause functional loss. There was objective evidence of tenderness or pain on palpation, pain with weight-bearing, and of crepitus. Repetitive use testing did not result in additional loss of function or ROM. The examiner opined that on repeated use over time and during flare-ups, that ROM would be limited from 10 to 60 degrees (due to pain and lack of endurance on repeated use, and due to pain on flare-ups). Muscle strength testing was 4/5 (compared to 5/5 on the right knee). There was no muscle atrophy or ankylosis. The examiner checked the appropriate boxes to notate a history of moderate recurrent subluxation and no history of lateral instability. Objective joint stability testing was normal in all planes (anterior, posterior, medial, and lateral). There were no shin splints, other tibial or fibular impairment, or genu recurvatum. The examiner noted a prior meniscal tear that was treated surgically; residuals include frequent episodes of joint pain and joint effusion. The ACL surgery residuals were noted as "severe left knee pain constantly." The examiner noted constant use of a walker. There was not functional impairment such that no effective function remains other than that which would be equally served by an amputation with prosthesis. The examiner opined that the left knee disability impacts the Veteran's ability to work because he requires use of a walker at all times due to constant left knee pain. The examiner noted that since the prior examination, the left knee disability "has increased in severity of pain and decreased ROM." He also noted that the Veteran was scheduled for a left knee replacement. VA treatment records during the appeal period and prior to the knee replacement surgery note complaints of chronic left knee pain, and treatment with periodic gel/steroid injections. On October 19, 2020, the Veteran underwent a left total knee arthroplasty. The postoperative diagnosis was left knee osteoarthritis. In May 2021, the claim was remanded for additional development, including namely an examination to assess the nature and severity of the now post-TKR disability. A VA (fee basis) knee examination was conducted in July 2021 (as discussed further in the Remand section below). [The Board notes that in July 2021, VA received a VA Form 21-4142 which identified treatment at Glasson Sports Medicine from November 2020 to present. Later that month, following telephone and facsimile correspondence, the provider notified VA that the request could not be processed due to a "date of treatment discrepancy." Accordingly, the record request was closed "as Dates of Treatment Discrepancy." 38 C.F.R. § 3.159(c). The duty to assist a claimant is not a one-way street. See Olsen v. Principi, 3 Vet. App. 480 (1992); see also Wood v. Derwinski, 1 Vet. App. 406 (1991). The Veteran has not submitted those records. (Notably, the surgical records and followup treatment records from HROSM were obtained and summarized above.)] Analysis Initially, the Board notes the applicability of Codes 5256, 5262, and 5263 has been considered throughout the appeal period. However, as the evidence of record does not show that pathology or separate and distinct symptoms required for ratings under such codes (ankylosis, nonunion or malunion of the tibia or fibula, or genu recurvatum of the knee) were present during the evaluation period, those Codes do not have applicability in this matter (and will not be further discussed). The Veteran's left knee disability has been assigned a 10 percent rating under Code 5257 for slight instability. The Board finds that more than slight instability is not shown at any time prior to October 19, 2020. In January 2014 (several months prior to the period for consideration), all ligaments were stable except for a notation of 1+ Lachman's test (used to evaluate ACL injury). A September 2018 treatment record notes the knee was "loose to varus and valgus stress," but not the severity of such. On April 2019 examination, there was 1+ anterior and posterior instability; medial and lateral stability were normal. And on March 2020 examination, objective joint stability testing was normal in all planes (anterior, posterior, medial, and lateral). The Board acknowledges the Veteran's March 2020 report of subjective "severe" instability, and also acknowledges that the March 2020 examiner checked the appropriate boxes to notate a history of moderate recurrent subluxation (and no history of lateral instability). The Board also acknowledges the CAVC's holdings in English v. Wilkie, 30 Vet. App. 347 (2018), and Tedesco v. Wilkie, 31 Vet. App. 360 (2019). However, the totality of the evidence is against a finding of more than slight instability. Objective testing throughout consistently showed normal stability or 1+ instability. No objective examination showed 2+ or 3+ instability. Accordingly, the Board finds that more than slight instability was not shown prior to October 19, 2020, and that a rating in excess of 10 percent under Code 5257 was not warranted. The Board turns to Codes 5258 and 5259, as the record shows the Veteran underwent a left knee meniscectomy during service. The Board finds that a 10 percent (maximum schedular) rating under Code 5259 is warranted from June 8, 2014 (a year prior to the June 8, 2015 date of claim) to October 19, 2020 (the date of the TKR surgery) for symptomatic removal of semilunar cartilage. During this period, the Veteran reported on numerous occasions (including in January 2014, several months prior to the beginning of the one-year look-back period beginning on June 8, 2014 under 38 C.F.R. § 3.400(o)(2)) that his left knee experienced swelling, locking, popping, and grinding. Notably, the April 2019 examiner found that residuals of the meniscal repair include joint swelling and locking, and the March 2020 examiner found residuals include frequent episodes of joint pain and effusion. Furthermore, the August 2015 examiner found objective evidence of crepitus, and a September 2017 treatment record notes "bone-on-bone arthritis medial compartment compared to more normal appearance of right knee joint articular cartilage." Importantly, no provider or examiner diagnosed a current meniscal tear. Accordingly, the Board finds the evidence at least in approximate balance that the Veteran's left knee disability manifested in symptomatic removal of semilunar cartilage, including effusion into the joint, popping sensation, grinding sensation, locking sensation, pain, and swelling. See Lynch v. McDonough, No. 2020-2067 (Fed. Cir. December 17, 2021). A rating under Code 5258 (for dislocated semilunar cartilage) is not warranted as the evidence does not show a meniscal tear during the period for consideration. Furthermore, separate ratings under Codes 5258 and 5259 are prohibited by the rule against pyramiding, as the two Codes contemplate overlapping symptoms. See 38 C.F.R. § 4.14. The Board turns to consideration of Codes 5260 and 5261 for limitation of ROM. Prior to September 12, 2017, the Veteran's left knee disability has been assigned a 10 percent rating under Codes 5003-5260 (for noncompensable limitation of flexion with arthritis). At no time under consideration is his left knee flexion shown to have been limited to 30 degrees (so as to warrant the next higher, 20 percent rating), or is left knee extension shown to have been limited to 10 degrees (so as to warrant a separate compensable rating for limitation of extension). On August 2015 examination, left knee ROM was 0 to 95 degrees. A November 2016 treatment record notes ROM was 0 to 100 degrees. It was not until September 12, 2017 when objective measurements conducted during examination/treatment showed greater limitation of ROM to warrant a higher rating. The Board acknowledges the Veteran's September 2019 hearing testimony expressing a belief that his left knee ROM in 2014 and 2015 was similar to that found in 2017, including with consideration of Swain v. McDonald, 27 Vet. App. 219 (2015). However, the Board finds the objective measurements recorded contemporaneously in the context of medical examination/treatment by medical professionals (including with use of a goniometer) more probative than lay recollections/estimates of ROM made four to five years later. Accordingly, a rating in excess of 10 percent is not warranted based on limitation of ROM (considering both flexion and extension) prior to September 12, 2017. From September 12, 2017 to October 19, 2020 (the date of TKR surgery), the Veteran's left knee disability has been assigned a 40 percent rating under Codes 5010-5261 (for limitation of extension with arthritis). At no time during this period is his left knee flexion shown to have been limited to 45 degrees (so as to warrant a separate compensable rating for limitation of flexion), or is left knee extension shown to have been limited at 45 degrees (so as to warrant the next higher, 50 percent rating). September 12, 2017 and September 2018 treatment records note that flexion was to 67 degrees (noncompensable) and extension was limited to 32 degrees (warranting the 40 percent rating currently assigned under Code 5261). On April 2019 examination, ROM was 0 to 90 degrees, and estimated at 0 to 80 degrees during repeated use over time and flare-ups. And on March 2020 examination, ROM was 5 to 70 degrees, and estimated at 10 to 60 degrees on repeated use over time and during flare-ups. Accordingly, a rating in excess of 40 percent from September 12, 2017 to October 19, 2020 is not warranted based on limitation of ROM (considering both flexion and extension), including during flare-ups or after repeated use over time. In summary, an increased (to 30 percent) combined rating is warranted from June 8, 2014 to September 12, 2017, based on a rating of 10 percent under Code 5257, 10 percent under Code 5259, and 10 percent under Codes 5003-5260. A combined rating in excess of 50 percent is not warranted from September 12, 2017 to October 19, 2020, even with consideration of the newly assigned 10 percent rating under Code 5259. [The Board notes (for information purposes) that the assignment of a separate 10 percent rating under Code 5259 does not have the effect of raising the combined rating for the left knee disability above 50 percent. See 38 C.F.R. § 4.25.] Finally, the record does not show, nor has the Veteran alleged, that he is unemployable due to his left knee disability. As noted above, the record shows that he worked as an engineer "in the field" during the earlier portion of the appeal period, and that he subsequently changed to a sedentary job. Although the physical role/nature of his employment may have changed, the evidence does not show that he is unable to work due to his left knee disability. Consequently, the matter of entitlement to a total rating based on individual unemployability (TDIU) is not raised by the record in the context of the instant claim for increase. See Shinseki v. Rice, 22 Vet. App. 447 (2009). [Notably, the Veteran is in receipt of a combined schedular 100 percent rating from March 28, 2019.] REASONS FOR REMAND 2. Entitlement to a combined rating in excess of 50 percent for the Veteran's post-TKR left knee disability from December 1, 2021 Post-TKR knee disability is rated under Code 5055. Prior to February 7, 2021, a 100 percent rating was to be assigned for 1-year following implantation of a prosthesis. Accordingly, a temporary total (convalescence under 38 C.F.R. § 4.30) rating was assigned in this appeal under Code 5055 from October 19, 2020 to December 1, 2021. See December 2020 rating decision. Under both the old and new regulations, following expiration of the temporary total (convalescence) rating period, a 60 percent [maximum schedular] rating is warranted for chronic residuals consisting of severe painful motion or weakness in the affected extremity. A 30 percent rating is the minimum rating to be assigned. And intermediate degrees of residual weakness, pain, or limitation of motion are to be rated by analogy to Codes 5256 (for ankylosis), 5261 (for limitation of extension), or 5262 (for impairment of the tibia and fibula). 38 C.F.R. § 4.71a. Here, the AOJ, in a December 2020 rating decision (merely two months after the Veteran's TKR knee surgery) issued a rating decision that continued the 40 percent rating assigned pre-TKR for limitation of extension. The rating decision did not address the 10 percent rating assigned pre-TKR for instability, nor did it address the criteria for rating post-TKR knee disability under Code 5055. [The Board notes that the combined rating continued in the December 2020 rating decision does not appear to correspond to the symptoms/manifestations shown on July 2021 VA (fee basis) knee examination.] Accordingly, remand for the AOJ to take all appropriate development indicated and re-rate the now post-TKR left knee disability, to include consideration of Code 5055 as prescribed for post-TKR knee disability is required. The matter is REMANDED for the following: Review the record, arrange for any further development suggested (to include, if indicated, an examination to assess the current severity of the Veteran's now post-TKR left knee disability), and readjudicate the matter remaining on appeal, specifically the rating for the knee from December 1, 2021, considering the Code 5055 criteria for rating post-TKR knee disability. GEORGE R. SENYK Veterans Law Judge Board of Veterans' Appeals Attorney for the Board J. Dupont, 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.