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 Common Peroneal Nerve Paralysis.
Altered walking pattern
Primary condition · VASRD 8528
Common Peroneal Nerve Paralysis
Paralysis or weakness in the lower leg affecting foot lift (foot drop).
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 Common Peroneal Nerve Paralysis — severity of Knee, Other Impairment of itself determines the percentage.
Example combined rating
30% Common Peroneal Nerve Paralysis + 20% Knee, Other Impairment of = 44%
The VA combines ratings with Table I of 38 CFR 4.25, not simple addition — 30% and 20% combine to 44%, not 50%. These figures are illustrative; your actual rating for each condition depends on your own evaluation.
Primary condition
Full Common Peroneal Nerve Paralysis guide
Secondary condition
Full Knee, Other Impairment of guide
See how Common Peroneal 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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