Strengthen Your Bone Density Test Coding
A deficient understanding of bone density measurement studies can cripple your ability to code properly.
by Ken Camilleis, CPC, CPC-I, CMRS, CCS-P
Bone density studies measure specific mineral values in targeted bony structures throughout the skeletal system, which allows a physician to diagnose osteoporosis (porous bone) or osteopenia (low bone density, the precursor to osteoporosis).
Is the Service Warranted?
Indications that warrant a bone density study vary. The National Osteoporosis Foundation (NOF), for example, recommends bone density testing under the following conditions:
- You are a woman age 65 or older
- You are a man age 70 or older
- You break a bone after age 50
- You are a woman of menopausal age with risk factors
- You are a postmenopausal woman under age 65 with risk factors
- You are a man age 50-69 with risk factors
Or a physician might order a bone density study for a patient who has had:
- An X-ray showing a spinal break or bone loss
- Back pain
- Loss of height more than 1/2 inch within one year
- Loss of height more than 1-1/2 inches from original height
Age is a key factor because the older a person gets, the more bone he or she tends to lose (reflected in ICD-9-CM classification as “Senile,” and in ICD-10-CM as “Age-related”). Gender is also a factor. Women are more prone to osteoporosis because they have smaller bones than men. Menopause can increase this risk as estrogen levels drop.
Based on a U.S. Preventive Services Task Force (USPSTF) recommendation, osteoporosis screening is available as a covered preventive service under the Affordable Care Act only for women aged 65 years or older, and in younger women whose fracture risk is equal to or greater than that of a 65-year-old woman who has no additional risk factors. The USPSTF says there is insufficient evidence to support screening for osteoporosis in men. Private payer policies may differ, so always check a patient’s coverage.
Bone Density Studies: A Primer
The most common, accurate method to measure bone density involves dual energy X-ray absorptiometry (DXA). DXA projects two X-ray beams to better assess bone density and can detect a variance as small as 3 percent from one scan to the next. Conventional X-rays are not sensitive enough to detect such small variances. DXA is especially effective for full-body skeletal assessments, as well as for focused studies of the hip, spinal column, and forearm (the skeletal areas most likely to break).
During a DXA scan, the patient rests on a cushioned platform. Mechanical arms are placed under the X-ray table and are aligned with an X-ray detector placed above the patient’s body. The amount of X-ray energy absorbed by the bone is measured to determine the strength of that bone. Less energy will pass through healthy bone than through osteopenic or osteoporotic bone.
Aside from using DXA, a bone density study might be conducted using:
- Peripheral DXA (pDXA) – Portable machines used to measure bone density in the arms or legs.
- Quantitative computed tomography (QCT) – This type of CT scan measures bone density in the spine.
- Peripheral QCT (pQCT) – This type of CT test measures bone density in the arms or legs.
- Dual photon absorptiometry (DPA) – This test uses a radioactive substance to measure bone density in the hip and spine.
- Quantitative ultrasound (QUS) – A portable machine used to measure bone density of the heel.
- Radiographic absorptiometry (RA) – This technique is most commonly used for bone density measurement at the hand or heel.
Analyze the Results
At the end of the bone density report, a summary graph compiles all of the data gathered into statistics for all regions examined in the study, tabulating each bone density, T-score, and Z-score. T- and Z-scores are baseline bone-specific values calculated based on guidelines published by the World Health Organization (WHO). The T-score is further influenced by statistics compiled by the NOF.
T-scores indicate whether there is normal bone strength, osteopenia, or osteoporosis:
|Bone Density Measurements|
|T-score||What it means|
|-1 and above||Normal|
|Between -1 and 2.5||Osteopenia|
|-2.5 and below||Osteoporosis|
|* A T-score higher than +1.0 indicates healthier than average bone for the patient’s age.|
Z-scores may assist in diagnosing secondary osteoporosis by calculating a value that takes into consideration the patient’s age and how he or she compares to an age-appropriate peer group with normal health in the bone being analyzed. According to WHO guidelines, a Z-score less than -1.5 is a red flag for further workup to diagnose or rule out secondary osteoporosis. The lower the Z-score, the more likely another factor besides the normal aging process is the cause of premature bone loss.
CPT® Coding for Bone Density Studies
Bone mineral density tests are reported with CPT® 77078 Computed tomography, bone mineral density study, 1 or more sites; axial skeleton (eg, hips, pelvis, spine), while DXA tests are coded according to site using the following CPT® codes:
77078 Computed tomography, bone mineral density study, 1 or more sites; axial skeleton
77080 Dual-energy X-ray absorptiometry (DXA), bone density study, 1 or more sites; axial skeleton (eg, hips, pelvis, spine)
77081 Dual-energy X-ray absorptiometry (DXA), bone density study, 1 or more sites; appendicular skeleton (peripheral) (eg, radius, wrist, heel).
77082 Dual-energy X-ray absorptiometry (DXA), bone density study, 1 or more sites; vertebral fracture assessment
76499 Unlisted diagnostic radiographic procedure
A bone density measurement and interpretation by ultrasound is reported with CPT® 76977 Ultrasound bone density measurement and interpretation, peripheral site(s), any method. Laboratory tests, such as those to assess calcium (82310-82340), iron (83540), magnesium (83735), and phosphate (84100-84105) also figure into the CPT® mix during patient care in maintaining or improving bone health.
Common diagnoses resulting from bone density studies may be reported with the following ICD-9-CM codes from Category 733 Other disorders of bone and cartilage:
733.1x Pathologic fracture
733.9x Other and unspecified disorders of bone and cartilage
Bone pain and other bone disorders may be coded from Category 719 Other and unspecified disorders of joint; or
733.90 Disorder of bone and cartilage, unspecified.
Report personal or family history of bone disorders with:
V13.89 Personal history of other specified diseases;
V17.81 Family history of osteoporosis; or
V17.89 Family history of other musculoskeletal disease.
Example 1: A 59-year-old man presents to his primary care physician (PCP) with the chief complaint of creaking knees: His knees ache and pop every time he rises from his living room sofa. He also has heard and felt occasional snaps in his groin and shoulder blades. The PCP does a limited exam of these three regions and orders bilateral X-rays of these regions.
- Established patient, expanded problem-focused history and exam, low-complexity medical decision-making (MDM): 99213
- Bilateral knee X-ray: 73565-26
- Bilateral hip X-ray: 73520-26
- Bilateral shoulder X-ray: 73050-26
Note that modifier 26 Professional service is applied to describe this as a physician (as opposed to a facility) service.
- Creaking knees: 719.66
- Creaking hips: 719.65
- Creaking shoulders: 719.61
Example 1, continued: The knee X-rays reveal a cartilaginous abnormality, and nothing can be concluded from the hip and shoulder X-rays (they appear negative). DXA scans are performed on the patient’s right and left femur right and left patella, and right and left shoulder. The studies reveal softening of cartilage in both knees, and low bone density scores with corresponding T-scores of -2.7 and -2.6 on the hips and -1.8 and -1.4 on the shoulders.
- DXA scans of femur: 77080-26 (report only once for each site in axial skeleton)
- DXA scans of patella and shoulder: 77081-26 (report only once for each appendicular si
- Chondromalacia of knees: 717.7 (by Excludes note from 733.92)
- Osteoporosis of hip bones: 733.00 (T-score below -2.5 indicates osteoporosis)
- Osteopenia of shoulder joints: 733.90 (T-score between -1.0 and -2.5 indicates osteopenia)
Repeat bone density studies may be ordered to assess improvement or exacerbation of bone weakness and to evaluate how a patient’s bone structure is responding to treatment.
Ken Camilleis, CPC, CPC-I, CMRS, CCS-P, is an educational consultant and PMCC instructor with Superbill Consulting Services, LLC. Camilleis is the new member development officer of Massachusetts’ Quincy Bay Coders local chapter.