First of all, you need to know whether the meniscal tear(s) are Acute/current or Chronic, which I agree your physician has to make clear in his documentation. If "acute/current," then the S83.2 Code Set would apply. In your case, S83.25 _ _ through S83.28 _ _ for the Lateral Meniscus would apply. If the tear(s) are not clearly designated Bucket-handle, Peripheral, or Complex, then you would have to go with "Other" tear, S83.28 _ _ ("Other" means "none of the above.")
If the tear(s) are Chronic, then you would have to look at M23.2: Derangement of the meniscus due to an "Old Injury," which seems restricted to Old Bucket Handle tears, which aren't necessarily the only types of old traumatic meniscal tears, and it would also seem to require that the patient can give a history of an "old injury," which they aren't always able to do. For the Lateral meniscus tears, if it is not isolated to the anterior or posterior horn, then it is "Other" tear of the Lateral Meniscus, M23.26 _.
If it doesn't clearly fall into M23.2, the you would have to use M23.3: "Other" meniscal derangements, which covers a lot more possible varieties of Chronic tears, and is probably better anyway. Again, if the tear is not designated as either the anterior or posterior horn, then it falls into "Other" meniscal tear of the Lateral Meniscus, M23.36 _ .
I hope this helps.
Respectfully submitted, Alan Pechacek, M.D.
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