ICD-10: Walk Through Skin and Subcutaneous Tissue Crossovers

Published in Coding Edge – March 2009
By Deborah Grider, CPC, CPC-H, CPC-I, CPC-P, CEMC, CPMA, COBGC, CPCD, CCS-P
Our journey using the ICD-10-CM roadmap leads us to draft guidelines and coding issues focusing on “Understanding the ICD-10-CM Draft Guidelines for the Skin and Subcutaneous Tissue.” Consider the codes for the Skin and Subcutaneous Tissue located in chapter 12 of ICD-10-CM.
In ICD-9-CM there are three subchapters in chapter 12:
680–686                Infections of skin and subcutaneous tissue
690–698                Other inflammatory conditions of skin and subcutaneous tissue
700–709               Other diseases of skin and subcutaneous tissue
These three subchapters were expanded in ICD-10-CM chapter 12 to include blocks L00-L99, as follows:
L00–L08               Infections of the skin and subcutaneous tissue
L10–L14                Bullous disorders
L20–L30               Dermatitis and eczema
L40–L45               Papulosquamous disorders
L50–L54                Urticaria and erythema
L55–L59                Radiation-related disorders of the skin and subcutaneous tissue
L60–L75                Disorders of skin appendages
L76                         Intraoperative and postprocedural complications of dermatologic procedures
L80–L99                Other disorders of the skin and subcutaneous tissue
Chapter 12 in ICD-10-CM was restructured to bring together related disease groups. Nearly all of the categories and subcategories in ICD-10-CM were expanded to either the fourth- or fifth-character level in this chapter. ICD-10-CM includes a number of category and/or subcategory title changes to adequately reflect the content. Diseases were grouped in either their own blocks or new categories to identify specific disease types.
Codes in ICD-9-CM moved to chapter 12 in ICD-10-CM:

ICD-9-CM	ICD-10-CM
704.1 Hirsutism	L68 Hypertrichosis
039.0 Erythrasma	L08.1 Erythrasma
136.0 Ainhum	L94.6 Ainhum

Decubitus Ulcers and Non-decubitus Chronic Ulcers of Lower Limbs

Decubitus ulcers were also expanded in ICD-10-CM. In ICD-9-CM, two codes are used to identify the decubitus ulcer and a secondary code is assigned to identify the pressure ulcer stage. In ICD-10-CM, only one code is needed to adequately describe the condition and the ulcer’s stage.
The codes in categories L89 Decubitus ulcer and L97 Non-decubitus chronic ulcer of lower limb, not elsewhere classified contain a great deal of detail.

The fourth character delineates the anatomy details (right versus left, upper versus lower).
The fifth character identifies the ulcer’s specific site.
The sixth character identifies ulcer depth.

For example: A physician is called by the nursing home to treat a patient with bed sores on the left buttock. After examining the patient, the physician documents decubitus ulcer, left buttock, stage II.
Compare a pressure ulcer (decubitus ulcer) of the left buttock:

ICD-9-CM

ICD-10-CM

707.0    Chronic ulcer of skin707.0    Pressure ulcer
                Bed sore
                Decubitus ulcer
                Plaster ulcer
                Use addition code to identify pressure
                ulcer stage (707.20-707.25)707.02 Buttock
707.2    Pressure ulcer stages
                Code first site of pressure ulcer (707.00-707.09)
707.20     Pressure ulcer, unspecified stage
707.21     Pressure ulcer stage I
707.22     Pressure ulcer stage II
707.23     Pressure ulcer stage III
707.24     Pressure ulcer stage IV
707.25     Pressure ulcer unstageable

L89        Pressure Ulcer                Includes:
                bed sore
                decubitus ulcer
                plaster ulcer
                pressure area
                pressure soreCode any association gangrene (I96)
L89.3       Pressure ulcer of buttock
L89.32     Pressure ulcer of left buttock
L89.321   Pressure ulcer of left buttock stage I
L89.322   Pressure ulcer of left buttock, stage II
L89.323   Pressure ulcer of left buttock, stage III
L89.324   Pressure ulcer of left buttock, stage IV
L89.329   Pressure ulcer of left buttock, unspecified stage

Using ICD-9-CM, two codes are necessary. The first listed diagnosis identifies the decubitus ulcer’s location and the secondary code describes the ulcer’s stage. In ICD-10-CM, only one code is necessary to describe both the pressure ulcer site and the ulcer’s stage. Notice the level of specificity in ICD-10-CM.
ICD-9-CM
707.02     Decubitus ulcer of the buttock
707.22     Pressure ulcer stage II
ICD-10-CM
L89.322   Pressure ulcer of left buttock stage II
When assigning a code for these ulcers using ICD-10-CM, review the record thoroughly to verify both the ulcer’s site and severity. For multiple ulcers of the same site, it is only necessary to assign a code for the most severe ulcer.
Any condition reducing blood flow to the legs may cause a lower limb ulcer. The same condition may also prevent an ulcer from healing, even with aggressive treatment. When the underlying condition is known, it should be sequenced before the ulcer.
Atherosclerosis of the lower extremities and diabetes mellitus are common underlying conditions. Combination codes for atherosclerosis of the lower extremities and diabetes mellitus include lower extremity ulcers.
The sequencing instructions at categories L89 and L97 differ slightly from the standard conventions, however. A serious decubitus ulcer that does not respond to treatment may be a reason for hospital admission. If decubitus ulcer is the reason for admission, it should be the principal, first-listed diagnosis. Secondary codes for the other decubitus ulcer-associated health problems should also be assigned. Generally, an underlying condition is responsible for a non-decubitus ulcer of the lower limb (L97).
An L97 code should be used with the combination code for the underlying condition to specify the ulcer’s site and depth. In some cases, no underlying cause for the ulcer is documented. In such cases, a code from L97 may be listed first.
The instructional note at L97 indicates the “code first” note is applicable only when an underlying condition is documented.
For example: A patient is treated in the outpatient hospital wound care clinic for a severe non-healing ulcer of the right midfoot and heel with bone necrosis due to diabetes mellitus.

Compare ICD-9-CM and ICD-10-CM codes

ICD-9-CM	ICD-10-CM
250.81 Diabetes with other specified manifestations, type I [juvenile type], not stated as uncontrolled707.14 Ulcer of heel and midfoot	E086.621 Diabetes mellitus due to underlying condition with foot ulcerL97.413 Non-pressure chronic ulcer of right heel and midfoot with necrosis of bone

Both decubitus and non-decubitus ulcers may become so severe that gangrene (necrosis of the tissue) sets in at the ulcer’s site. For gangrene cases resulting from a skin ulcer, the gangrene should be sequenced first, followed by the code for the ulcer.
When gangrene is present, the primary focus of treatment is to remove the gangrene, usually with debridement or amputation of the affected area. The “code first” note at categories L89 and L97 instructs that gangrene should be sequenced before the ulcer. This note applies only if gangrene is present.
For example: A patient with a gangrenous pressure ulcer of the right ankle, with necrosis of the muscle and bone is treated for debridement of the area.
Review the comparison:

ICD-9-CM	ICD-10-CM
707.06 Pressure ulcer, ankle707.24 Pressure ulcer, stage IV785.4 Gangrene	I96 Gangrene, not elsewhere classifiedL89.514 Pressure ulcer of right ankle, stage IV

Using ICD-9-CM, gangrene of the lower extremities instructional notes state to code first any associated condition. In the example above, the pressure ulcer and the ulcer’s stage are coded first and second, with the gangrene as a tertiary diagnosis. In ICD-10-CM, the instructional notes identifies that gangrene is coded first, followed by the pressure ulcer. This differs from ICD-9-CM instructions.
A secondary external cause code identifying the exposure’s source should be used when reporting categories L56 Other acute skin changes due to ultraviolet radiation and L57 Skin changes due to chronic exposure to non-ionizing radiation.
For example: A female patient who uses a tanning bed in her apartment daily is treated by a dermatologist for multiple solar keratoses on her face due to overexposure in the tanning bed.
Compare ICD-9-CM and ICD-10-CM:

ICD-9-CM	ICD-10-CM
702.0 Actinic keratosesE926.2 Visible and ultraviolet light sourcesE849.0 Place of occurrence, home	L57.0 Actinic keratoses (solar)W89.1 Exposure to tanning bedY92.039 Place of occurrence apartment

With both ICD-9-CM and ICD-10-CM, the condition followed by the external cause code is reported. Because the location of the overexposure is known, it can be reported as well. Notice in ICD-10-CM, the place of occurrence states “apartment.”
The place of occurrence codes for home is sub-divided to include apartment, boarding home, single family residence, institution, nursing home, prison, reform school dormitory, and mobile home. These categories are further divided to include areas of the home including, bathroom, bedroom, driveway, garden, kitchen, swimming pool, etc.
Compare ICD-9-CM and ICD-10-CM place of occurrence residential codes for an apartment and a single family home:

Y92.00 residence (non-institutional) (private)	Y92.00 residence (non-institutional) (private)
Y92.039 apartment Y92.031 bathroom Y92.032 bedroom Y92.030 kitchen Y92.038 specified NEC	Y92.019 house, single family Y92.010 kitchen Y92.011 dining room Y92.012 bathroom Y92.013 bedroom Y92.014 driveway Y92.015 garage Y92.016 swimming pool Y92.017 garden or yard Y92.018 specified NEC

ICD-10-CM category L76 Intraoperative and postprocedural complications of dermatologic procedures is a new subsection found in chapter 12 that is divided into fourth and fifth characters:

Fourth character describes complications and conditions following surgery, such as hemorrhage and hematoma
Fifth character further specifies the complication

Examples of postprocedural complications in ICD-10-CM include:
L76          Intraoperative and postprocedural complications of skin and subcutaneous tissue
                L76.0       Intraoperative hemorrhage and hematoma of skin and subcutaneous tissue complicating a procedure
                Excludes: Intraoperative hemorrhage and hematoma of skin and subcutaneous tissue due to accidental puncture during a procedure (L76.1-)
                                L76.01     Intraoperative hemorrhage and hematoma of skin and subcutaneous complicating a Dermatologic procedure
                                L76.02     Intraoperative hemorrhage and hematoma of skin and subcutaneous complicating other procedure
                L76.1       Accidental puncture and laceration of skin and subcutaneous tissue during a procedure
                                L76.11     Accidental puncture and laceration of skin and subcutaneous tissue during a dermatologic procedure
                                L76.12     Accidental puncture and laceration of skin and subcutaneous tissue during other procedure
                L76.2       Postprocedural hemorrhage and hematoma of skin and subcutaneous tissue following a procedure
                                L76.21     Postprocedural hemorrhage and hematoma of skin and subcutaneous tissue following a dermatologic procedure
                                L76.22     Postprocedural hemorrhage and hematoma of skin and subcutaneous tissue following other procedure
                L76.8       Other intraoperative and postprocedural complications of skin and subcutaneous tissue
                                Use additional code, if applicable to further specify disorder
                                L76.81     Other intraoperative complications of skin and subcutaneous tissue
                                L76.82     Other postprocedural complications of skin and subcutaneous tissue
Some of the codes in chapter 12 of ICD-10-CM have been expanded further to include notes directing the coder to use an additional code:

Use additional code (B95–B97) to identify organism
Code first (T36–T65) to identify drug or substance
Code first underlying disease
Code first any associated

For example:
L00–L08 Infections of the skin and subcutaneous tissue
                                Use additional code (B95–B97) to identify infectious agent
                L02          Cutaneous abscess, furuncle and carbuncle
                                Use additional code to identify organism (B95–B96)
                L23         Allergic contact dermatitis
                                Code first (T36–T65) to identify drug or substance
Because ICD-10-CM codes are expansive compared to ICD-9-CM codes, coding skin and subcutaneous tissue will be challenging. Detail and specificity in documentation are the key ingredients to successfully coding ICD-10-CM skin and subcutaneous tissue.