R22.4Localized swelling, mass and lump, lower limb

R22.4 is the ICD-10-CM diagnosis code for localized swelling, mass and lump, lower limb. It belongs to category R22 (localized swelling, mass and lump of skin and subcutaneous tissue), block R20-R23 (symptoms and signs involving the skin and subcutaneous tissue) and chapter 18 (symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.

Within R22 (localized swelling, mass and lump of skin and subcutaneous tissue), R22.4 is specifically for localized swelling, mass and lump, lower limb. Related codes cover head (R22.0), neck (R22.1), trunk (R22.2), upper limb (R22.3) and unspecified (R22.9).

To report this condition, pick the subcode that matches the documentation: R22.40 (limb), R22.41 (limb), R22.42 (limb) and R22.43 (bilateral).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.