The Board has remanded the claims for service connection for right and left knee injuries due to inadequate examination, failure to address lay assertions of symptomatology in and since service, and lack of consideration of relevant medical treatises.

The Veteran was granted a total disability rating due to individual unemployability from December 2, 2019 to June 15, 2021 on an extraschedular basis.

The Veteran's sleep apnea was rated at 50 percent, but the Board found that it did not meet the criteria for a higher rating due to lack of chronic respiratory failure with carbon dioxide retention or cor pulmonale.,For the left knee injury prior to November 25, 2014, the Veteran received a 10 percent rating based on painful motion. After November 25, 2014, he was granted a 30 percent rating for limitation of extension and flexion due to pain.,The Veteran's major depressive disorder did not meet criteria for higher ratings.,For the low back disability, the Veteran received a 40 percent rating based on forward flexion greater than 30 degrees. The Board found no evidence of ankylosis or incapacitating episodes.,ED was denied as there was no deformity of the penis.

The Board denied the Veteran's claim for service connection for a right knee disability and granted a 10 percent rating for residuals of right ankle sprain, effective April 20, 2010. The decision also found that the Veteran’s current right knee disability is not related to his service-connected ankle condition.

The Veteran's appeal is remanded due to the need for further evaluation regarding his entitlement to higher levels of SMC and a rating increase for his residual left knee injury. The Board found that he does not meet the legal criteria for SMC under 38 U.S.C. § 1114(o) based on the lack of anatomical loss or use in his feet, hands, or eyes.