The use of an “unspecified” ICD-10-CM code normally indicates that the documentation did not contain the information that was necessary to select the appropriate specific code.
ICD-10-CM coding for a diabetic foot ulcer requires multiple ICD-10-CM codes. One of them is an L97- code. The 6th character of the L97- ICD-10-CM codes indicates the depth of the ulcer. If a patient had a left plantar heel diabetic foot ulcer whose deepest depth of tissue exposed was subcutaneous tissue, the L97- code options would include:
L97.421 Non-pressure chronic ulcer of left heel and midfoot limited to breakdown of skin
L97.422 Non-pressure chronic ulcer of left heel and midfoot with fat layer exposed
L97.423 Non-pressure chronic ulcer of left heel and midfoot with necrosis of muscle
L97.424 Non-pressure chronic ulcer of left heel and midfoot with necrosis of bone
L97.425 Non-pressure chronic ulcer of left heel and midfoot with muscle involvement without evidence of necrosis
L97.426 Non-pressure chronic ulcer of left heel and midfoot with bone involvement without evidence of necrosis
L97.428 Non-pressure chronic ulcer of left heel and midfoot with other specified severity
L97.429 Non-pressure chronic ulcer of left heel and midfoot with unspecified severity
If the documentation of this ulcer were thoroughly and properly performed, it would describe that the deepest depth of tissue exposed was subcutaneous tissue. However, a selection of L97.429 would indicate that the documentation was incomplete and did not specify the severity of the ulcer, when in fact it did specify that the deepest depth of tissue exposed was subcutaneous tissue. We cannot state in our coding that something was not specified in the documentation when that thing actually was specified in the documentation. This is an example of the ICD-10 coding not matching the documentation. The more appropriate selection in this example would be L97.422, reflecting the thorough documentation that did in fact, specify the depth of the ulcer.
Incorrect ICD-10-CM coding can be problematic in the case of an audit performed by a third-party payer or representative. If the documentation specified what it should, but the ICD-10-CM code selected indicates this specification was not present, a case for incorrect coding could be made. Furthermore, more third-party payers are denying payment for services submitted with “unspecified” ICD-10 codes.
Avoid the use of “unspecified” ICD-10-CM codes. When caring for wounds, always document laterality, body part involved, and wound depth and choose corresponding ICD-10-CM codes that specify laterality, body part involved and wound depth.
Dr. Lehrman is in private practice in Fort Collins, CO and operates Lehrman Consulting, LLC. He is a Diplomate of the American Board of Foot and Ankle Surgery, Fellow of the American Society of Podiatric Surgeons, and is recognized as a “Master” by the American Professional Wound Care Association. He is a Fellow of the American Academy of Podiatric Practice Management and an Expert Panelist on Codingline. In his role as a Consultant to the APMA Health Policy and Practice Department, Dr. Lehrman serves as an advisor to the APMA Coding Committee and the APMA MACRA Task Force. Dr. Lehrman sits on the board of directors of both the American Professional Wound Care Association and the American Society of Podiatric Surgeons. He is also on the editorial advisory board of the journal WOUNDS.