Orthopedic Coding Alert

Calcification and ossification location matters in ICD-10.

Myositis coding can be challenging as you're attempting to identify the right type from a broad range of conditions that fall under the category of myosisits. In 2013, you'll be looking at the specific site involved. Many ICD-10 codes include 'unspecified site' in the descriptors. See the advice below for optimal myositits code selection when ICD-9 transitions to ICD-10.

Look for 'Unspecified Site' in Descriptors

ICD-10 descriptors for the codes relating to musculoskeletal system and connective tissue disorders are more elaborate as these include the mention of 'unspecified site'.

Example: ICD-9 code for infective myositis 728.0 (Infective myositis) maps to M60.009 (Infective myositis, unspecified site) in ICD-10. Similarly, the codes for myositis ossificans, heterotopic calcification, interstitial myositis, muscle rupture, and wasting and disuse atrophy of muscles include 'unspecified site' in the descriptors. Check out this list below.

• Code 728.11 (Progressive myositis ossificans) in ICD-9 maps to M61.10 (Myositis ossificans progressiva, unspecified site) in ICD-10.
• Code 728.12 (Traumatic myositis ossificans) in ICD-9 maps to M61.00 (Myositis ossificans traumatica, unspecified site) in ICD-10.
• Code 728.2 (Muscular wasting and disuse atrophy not elsewhere classified) in ICD-9 maps to M62.50 (Muscle wasting and atrophy, not elsewhere classified, unspecified site) in ICD-10.
• Code 728.81 (Interstitial myositis) in ICD-9 maps to code M60.10 (Interstitial myositis of unspecified site) in ICD-10.
• 728.83 (Rupture of muscle nontraumatic) maps to M62.10 (Other rupture of muscle [nontraumatic], unspecified site)

ICD-10 codes also are more specific for the structure affected. For example, the code for unspecified calcification and ossification in ICD-9, 728.10 (Calcification and ossification unspecified) reads more specific in code M61.9 (Calcification and ossification of muscle, unspecified) in ICD-10.

Look at Location, Side, Cause for Myositis Ossificans

Going further in 2013, you will have a variety of codes to choose from for myosistis ossficans. "There are numerous ICD-10 codes describing myositis ossificans that range from M61.00 through M61.19. These are broken down by body location, side of the body (RT/LT) or unspecified (if unknown) and as traumatic versus progressive," says Kristi Stumpf, MCS-P, CPC, COSC, ACS-OR, owner, Precision Auditing and Coding, senior orthopedic coder & auditor, The Coding Network, Washington.

You need to be specific for traumatic versus progressive varieties of myositis ossificans. "Myositis ossificans progressive is listed with code series M61.10-M61.19. Myositis ossificans traumatica is listed with the code series M61.00-M61.09," says Stumpf.

The ICD-9 codes for these conditions are 728.11 and 728.12, respectively. Underline the differences in ICD-9 and ICD-10 for these codes. "The difference with ICD-10 is the specificity of the codes. For ICD-10, the coder will need to know the specific location, the side of the body, and the type of myositis ossificans (traumatic or progressive) for proper code selection. There is a specific ICD-10 code for "other sites" and for "multiple sites" for both the progressive and traumatica categories," says Stumpf.

Editor's note: Follow the next issue for further updates on muscle and ligament disorders.