Which ICD-10-CM diagnosis code should I use to obtain approval for a dual-energy X-ray absorptiometry (DEXA) scan in a 77-year-old patient with osteopenia on recent X-ray, scoliosis, mild facet arthropathy, cervical spine (C-spine) involvement, a history of smoking, and hyperlipidemia?

Diagnosis Code for DEXA Scan Authorization

Use ICD-10 code M81.8 (Other osteoporosis) as your primary diagnosis code for this 77-year-old patient with osteopenia documented on X-ray, which provides the strongest justification for DEXA scan approval. 1

Primary Coding Strategy

M81.8 (Other osteoporosis) is the most appropriate code because:

• Your patient has radiographically documented osteopenia, which represents established low bone mineral density requiring quantitative assessment 1
• At age 77, this patient falls into the category where DEXA screening is explicitly recommended by guidelines for asymptomatic BMD screening 1
• The ACR Appropriateness Criteria rates DXA lumbar spine and hip(s) as 9/9 (usually appropriate) for individuals with established or clinically suspected low BMD 1

Supporting Secondary Codes to Strengthen Authorization

Add these secondary diagnosis codes to bolster medical necessity:

• M41.9 (Scoliosis, unspecified) - The presence of scoliosis is particularly relevant because the ACR guidelines specifically address patients >50 years with advanced degenerative changes of the spine with or without scoliosis, rating QCT highly but also supporting DXA evaluation 1

• Z87.891 (Personal history of nicotine dependence) - History of smoking is a recognized risk factor for osteoporosis and fracture risk, strengthening the clinical indication 1

• M54.5 (Low back pain) - If applicable, this can support the clinical context given the scoliosis and facet arthropathy 2

Why This Coding Approach Works

The combination of documented osteopenia on imaging plus age >65 creates an unassailable clinical indication:

• Insurance payers recognize that radiographic osteopenia requires quantitative confirmation via DEXA to determine fracture risk and guide treatment decisions 1
• The ACR explicitly rates DXA as the gold standard (9/9 rating) for patients with clinically suspected low BMD 1
• Your patient's age alone (77 years) meets criteria for routine BMD screening in most guidelines 1

Common Pitfalls to Avoid

Do not use screening codes (Z13.820 - Encounter for screening for osteoporosis) as your primary diagnosis:

• Screening codes may be denied for patients who already have documented abnormalities on imaging 3
• Your patient has osteopenia on X-ray, making this a diagnostic rather than screening scenario 1

Do not use M80.08 (Age-related osteoporosis with current pathological fracture) unless there is a documented fracture:

• This code requires evidence of fracture, which is not mentioned in your clinical scenario 2

Order Specifications

When ordering the DEXA scan, specify:

• "DXA lumbar spine and hip(s)" - This is the ACR-recommended standard with a 9/9 appropriateness rating 1
• Include both anatomic sites, as assessment of fracture risk requires measurement of spine and proximal femur, not either site alone 4
• Note the scoliosis in your clinical indication, as this may affect interpretation and site selection 1

Clinical Documentation Tips

In your order notes, document:

• "77-year-old with osteopenia noted on recent X-ray requiring quantitative assessment"
• "History of scoliosis with degenerative changes"
• "Risk factors include advanced age and smoking history"
• This documentation aligns with the clinical scenarios rated 9/9 by ACR guidelines 1