Secondary Condition Claim · VASRD 5257
A condition caused or aggravated by an already service-connected disability can be granted its own service connection as a secondary condition under 38 CFR § 3.310. Here's how that works for Knee, Other Impairment of when it develops after Anterior Crural Nerve Paralysis.
Femoral nerve supports thigh muscles
Primary condition · VASRD 8526
Anterior Crural Nerve Paralysis
The anterior crural nerve is the traditional anatomical name for the femoral nerve, so this code covers the same nerve as femoral nerve paralysis - damage affecting the ability to extend the knee and the strength of the thigh muscles. If your rating decision uses this older terminology, the underlying condition and evidence needed are the same as for femoral nerve paralysis.
Secondary condition · VASRD 5257
Knee, Other Impairment of
This diagnostic code covers knee instability - the knee buckling, giving out, or feeling loose during activity - separate from simple pain or arthritis. It's rated on how often and how severely the knee subluxates (partially dislocates) or shifts out of place, which is a different rating track than knee pain alone.
The VA rates Knee, Other Impairment of the same way whether it's claimed directly or as secondary to Anterior Crural Nerve Paralysis — severity of Knee, Other Impairment of itself determines the percentage.
Example combined rating
20% Anterior Crural Nerve Paralysis + 20% Knee, Other Impairment of = 36%
The VA combines ratings with Table I of 38 CFR 4.25, not simple addition — 20% and 20% combine to 36%, not 40%. These figures are illustrative; your actual rating for each condition depends on your own evaluation.
Primary condition
Full Anterior Crural Nerve Paralysis guide
Secondary condition
Full Knee, Other Impairment of guide
See how Anterior Crural Nerve Paralysis and Knee, Other Impairment of combine with the rest of your service-connected conditions using the official VA combined-ratings formula.
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