- C—The guideline for coding from category M81._ is that an additional code is needed if the physician has knowledge that the patent had a past pathological fracture. The code for personal history of (healed) pathological fracture is Z87.310.
- B—Osteoporosis with a current pathologic fracture is one of the few ICD-10 codes that require seven characters, which rheumatology practices will utilize. ICD-10 codes can be three, four, five, six or seven characters. The seventh character is called an extension character. They are there for injuries and external causes to categorize the type of encounter and are defined as follows:
- A—Initial encounter: This is used as long as the patient is in active treatment; whether a new or established patient.
- D—Subsequent encounter: This is used during routine healing.
- S—Sequelae: For late affect problems related to the injuries or external causes.
- C—Code the presenting problem first, then code the pregnancy, which is incidental to the encounter (Z33.1: Pregnant state, incidental).
- A—This means the two codes are mutually exclusive and cannot be coded during the same encounter. An example of this is chronic gout and acute gout; these two codes should not be coded and billed during the same encounter. The physician will need to code and bill based on his or her clinical decision of the presenting problem for that encounter.
- False—This coding guideline falls under the “Excludes 1” rule. If coding M15.0 for general osteoarthritis, then no other codes with bilateral joint involvement can be coded during the same encounter, as they are mutually exclusive.