Osteopenia is a condition characterized by lower than normal bone mineral density, often found as people age. It represents a stage of bone weakening that has not yet progressed to the more severe state of osteoporosis. Classification systems like the International Classification of Diseases, 10th Revision (ICD-10), provide standardized codes for tracking, research, and medical billing. Understanding the specific ICD-10 code is necessary for accurate medical record-keeping and clinical management.
The Specific ICD-10 Code for Osteopenia
The core classification for osteopenia falls under the code M85.8, which translates to “Other specified disorders of bone density and structure.” This category is used when the diagnosis confirms low bone mass that is not severe enough to be classified as osteoporosis. The M85.8 code acts as the starting point for coding osteopenia, placing it within the broader group of bone density issues. However, M85.8 itself is non-billable and signals that further characters are required to complete the diagnosis code for official use. The hyphen at the end of the M85.8 code indicates that additional characters are needed to specify the exact anatomical site affected by the low bone density.
Completing the Code for Site Specificity
To achieve the necessary specificity, the ICD-10 code for osteopenia requires a fifth character to designate the anatomical location. For example, the code may be extended to M85.85 for findings in the thigh region or M85.88 if the condition is found at an “other specified site.” Common sites assessed for bone density, such as the forearm, hip, and spine, each have a specific code within the M85.8 series.
If the documentation indicates osteopenia is present at two or more separate locations, the code M85.89 is used to denote “multiple sites.” When the medical record does not specify the affected location, the code M85.80 is available for use, indicating an “unspecified site.”
How Osteopenia Differs from Osteoporosis
The clinical distinction between osteopenia and osteoporosis is determined by a T-score, which is derived from a Dual-energy X-ray Absorptiometry (DXA) scan. A T-score compares a patient’s bone density to that of a healthy young adult. Osteopenia is diagnosed when the T-score falls between -1.0 and -2.5, indicating bone density that is below average.
In contrast, a T-score of -2.5 or lower signifies osteoporosis, where the risk of fracture is significantly increased. This difference in severity dictates the use of entirely separate ICD-10 categories: M85.8 for osteopenia and the M81 series for osteoporosis (or M80 if a fracture is present).