Bone mineral density (BMD) measurement is a non-invasive technique that is used to measure bone mineral content and bone mineral density. Its primary role is to detect osteoporosis and to predict the risk of fractures. Dual-energy absorptiometry (DEXA) is the most commonly used technique to measure BMD. This document addresses peripheral bone density studies including the use of heel densitometry, peripheral dual energy x-ray absorptiometry (pDEXA), radiographic absorptiometry of the fingers, single energy X-ray absorptiometry (SEXA), single photon absorptiometry (SPA), and dual X-ray and laser (DXL).

Note:  For information on central bone density measurements and screening of vertebral fractures using DEXA, please refer to CG-MED-39 - Central (Hip or Spine) Bone Density Measurement and Screening for Vertebral Fractures Using Dual Energy X-Ray Absorptiometry. 

Medically Necessary:

Peripheral bone density measurement using the forearm (cortical bone), is considered medically necessary when performed for individuals (male or female) with asymptomatic primary hyperparathyroidism (PHPT) where consideration for surgery is in large part determined by bone density level.

Investigational and Not Medically Necessary: 

Peripheral bone density studies are considered investigational and not medically necessary for all indications other than asymptomatic primary hyperparathyroidism, including but not limited to, the following methods:

1. Peripheral dual energy x-ray absorptiometry (pDEXA)
2. Radiographic absorptiometry of the fingers
3. Single energy X-ray absorptiometry (SEXA)
4. Single photon absorptiometry (SPA)
5. Dual X-ray and laser (DXL)
6. Ultrasound of the heel

Peripheral bone density studies are considered investigational and not medically necessary for asymptomatic primary hyperparathyroidism if performed on any part of the body other than the cortical bone (e.g. radiographic absorptiometry of the fingers, ultrasound of the heel).

Bone Mineral Density Measurements
Bone mineral density (BMD) tests are used to measure the content of calcium and other minerals in the bones.  There is currently some controversy over whether central (central hip and spine) or peripheral (e.g. forearm, finger and heel) measurements provide superior results.  Central measurements are more commonly performed because bone loss most frequently occurs in the spine and hip regions.  However, there are some conditions (such as hyperparathyroidism) in which bone loss occurs more rapidly at the peripheral sites and peripheral measurements may therefore be more appropriate.  For information regarding central bone density measurements, please refer to CG-MED-39 Central (Hip or Spine) Bone Density Measurement and Screening for Vertebral Fractures Using Dual Energy X-Ray Absorptiometry. 

Peripheral Bone Mineral Density Measurements
The American Association of Clinical Endocrinologists (AACE) and the American Association of Endocrine Surgeons (AAES) position statement on the diagnosis and management of primary hyperparathyroidism indicates that losses of bone mineral density (BMD) from primary hyperparathyroidism (PHPT) are more pronounced in the forearm (cortical bone) than in the spine (trabecular bone) and hip (mixed cortical and trabecular bone) but may occur at all skeletal sites.  Although forearm losses of BMD may be more commonly associated with PHPT, the benefit from surgical treatment is more notable for the hip and spine because of the morbidity and mortality associated with fracture.  The position statement asserts that patients with PHPT should undergo DEXA scanning of these 3 sites for reliable documentation of their BMD status as a criterion for recommending parathyroidectomy.  For more information regarding bone mineral density measurements of the hip or spine, refer to CG-MED-39 Central (Hip or Spine) Bone Density Measurement and Screening for Vertebral Fractures Using Dual Energy X-Ray Absorptiometry.

Chappard and colleagues studied females with primary hyperparathyroidism and healthy women to assess the bone mineral density (BMD) status in primary hyperparathyroidism (PHPT).  Their results suggested that low BMD at lumbar spine and femur is encountered preferentially in premenopausal women.  The BMD decrease predominates at limbs in PHPT with presumably a gradient from proximal to distal part of the limbs.  Indeed, the distal part of the limbs are the most affected areas in PHPT whatever the amount of cortical or trabecular bone.

Peripheral bone density studies for all other indications other than asymptomatic primary hyperparathyroidism need further study to standardize results and ascertain accuracy as well as clinical utility for other populations. 

Ultrasound Heel Densitometry versus DEXA
Because of the slow changes in bone mineral density and the precision of measuring technologies, specifically DEXA, monitoring response to therapy prior to two years is unlikely to detect changes.  In addition, changes in bone mineral density at central sites (i.e., hip and spine) are often not reflected by changes in bone mineral density at peripheral sites.  Therefore, the use of ultrasound densitometry of the heel is not an effective tool for monitoring response to therapy.

The precision of ultrasound heel densitometry is lower than that of DEXA.  With additional research, ultrasound heel densitometry may be shown to have clinical potential as a screening tool for osteoporosis, however, at the present time, data do not support the routine use of ultrasound densitometry as a screening or diagnostic tool or as a means to monitor response to therapy.  The full potential of this technology cannot be realized without additional studies on the precision, accuracy, reproducibility, and validity of ultrasound densitometry in the clinical setting.

Description of Disease
Osteoporosis is a serious public health problem, characterized by slow, prolonged bone loss.  The National Osteoporosis Foundation in 2008 noted that in the United States 10 million individuals are estimated to have osteoporosis, including 55 percent of people age 50 years and older.  The disease is four times more likely to occur in women than in men.  In addition, almost 34 million more are estimated to have low bone mass, placing them at increased risk for osteoporosis.  About 1.5 million fractures annually are due to osteoporosis.  These fractures are most common at the hip, spine, and wrist and can result in serious morbidity and in some cases death.  The incidence of osteoporosis in the U.S. is expected to increase significantly in the future as the population ages. 

Treatment of Disease
The goal of osteoporosis treatment is to prevent or decrease the rate of bone loss.  Such treatment may include, but is not necessarily limited to calcium and vitamin supplementations, exercise and medications such as calcitonin, parathyroid hormone, estrogens, bisphosphonates (alendronate, ibandronate and risedronate), and raloxifene.  Treatment planning represents a joint decision by the treating physician and the patient (male/female) following discussion of the potential risks and benefits of therapy. 

Description of Technology
Bone densitometry is a non-invasive technique that is used to measure bone mineral content in order to predict fracture risks and need for medical therapy.  BMD can be measured at several anatomical locations.  Peripheral BMD is generally determined by obtaining measurements at the wrist, forearm, finger or heel, while central BMD measurements are obtained from the hip or spine.  BMD is typically expressed as the T-score (e.g., the number of standard deviations [SD] below the mean for non-osteopenic, healthy, young women).  The World Health Organization defines osteopenia as a T-score of between –1.0 and -2.5 SD, and osteoporosis as a score of –2.5 SD or more.

The following technologies for peripheral measurement of bone mineral content are available:

1. Dual Energy X-ray Absorptiometry (DEXA) for measurement of BMD - DEXA (DXA) is the most commonly used technique to measure BMD because of its ease of use, low radiation exposure, and its ability to measure BMD at both hip and spine.  DEXA uses two x-ray beams of different energy levels to scan the region of interest and measure the amount of X-rays absorbed by the bone as the beam passes through the body.  When DEXA is done at peripheral sites such as the forearm, as opposed to more central locations like the hip and spine, it is usually referred to as pDEXA.
2. Quantitative Ultrasonography Scanning (QUS) - Quantitative ultrasonography scanning measures bone mass and strength and assesses bone microarchitecture by detecting the transmission of high-frequency sound waves through bone.  QUS results are reported as broadband ultrasound attenuation (BUA) and the speed of sound (SOS).  These two parameters are sometimes combined to yield a "stiffness index".  QUS is a relatively new technique for measuring bone mass at peripheral sites such as heel, tibia, and phalanges.  It does not use ionizing radiation and has the advantage of being small, portable, and relatively inexpensive.  However, this technique has not been shown to be useful in monitoring skeletal response to the different therapies used to treat osteoporosis.
3. Dual-Photon Absorptiometry (DPA) - DPA measures bone mineral content at the spine and hip using photons emitted at low energy levels.  It is also used to measure total body calcium and provides a measurement of mineral density in both long bones and bones such as the heel.  This method measures the total mineral content in the path of the beam.
4. Dual X-ray and Laser (DXL) – DXL is a new technique that is presently being researched. It uses two X-ray beams in combination with a laser.  The suggestion is that this technique has the advantage of filtering out any influence that adipose tissue inside and outside the bone may have on the accuracy of DEXA measurements.  DXL has been studied using peripheral sites such as the heel.

The following techniques are less commonly used for bone densitometry:

1. Single energy x-ray absorptiometry (SEXA);
2. Single photon absorptiometry (SPA);
3. Radiographic absorptiometry (RA)

Central bone density measurement: An imaging procedure where the density of either the hip or spine is measured using a method that determines bone density by measuring x-rays passing through the bone.

Dual Energy X-ray Absorptiometry (DEXA): A test which uses two x-ray beams of different energy levels to scan the region of interest and measure the amount of X-rays absorbed by the bone as the beam passes through the body. When DEXA is done at peripheral sites such as the forearm, as opposed to more central locations like the hip and spine, it is usually referred to as pDEXA.

pDEXA: A bone mineral density study using dual energy X-ray absorptiometry (DEXA) to evaluate bone density at peripheral sites (e.g., heel or wrist) rather than at central sites such as the hip or spine.

Peripheral Bone Density Studies: Bone density studies using sites other than the hip or spine.

Postmenopausal women: Women who have passed the age of child bearing.

Single energy X-ray absorptiometry (SEXA): This technology uses a different process than DEXA or pDEXA and is used specifically for the measurement of bone density of peripheral (appendicular) skeletal sites such as the wrist or heel.

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy.  Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met: 

When services are Investigational and Not Medically Necessary:
For the procedure codes listed above when criteria are not met or for all other diagnoses not listed; or when the code describes a procedure indicated in the Position Statement section as investigational and not medically necessary.

When services are also Investigational and Not Medically Necessary: 

Future ICD-10 coding (effective 10/01/2013)
A draft of ICD-10 Coding related to this document, as it might look today, is available for reference and comments at: Appendix 1: Future ICD-10 coding

Peer Reviewed Publications:

1. Amin S, Felson DT. Osteoporosis in men. Rheum Dis Clin North Am. 2001; 27(1):19-47.
2. Blake GM, Fogelman I. Peripheral or central densitometry: does it matter which technique we use? J Clin Densitom. 2001; 4(2):83-96.
3. Campion JM, Maricic MJ. Osteoporosis in men. Am Fam Physician. 2003; 67(7):1521-1526.
4. Chappard C, Roux C, et al. Bone status in primary hyperparathyroidism assessed by regional bone mineral density from the whole body scan and QUS imaging at calcaneus. Joint Bone Spine 2006; 73(1): 86-94.
5. Chen T, Chen PJ, Fung CS, et al. Quantitative assessment of osteoporosis from the tibia shaft by ultrasound techniques. Med Eng Phys. 2004; 26(2):141-145.
6. Cummings SR, Bates D, Black DM. Clinical use of bone densitometry: scientific review. JAMA. 2002; 288(22):1889-1897.
7. Deal CL. Using bone densitometry to monitor therapy in treating osteoporosis: pros and cons. Curr Rheumatol Rep. 2001; 3(3):233-239.
8. Gonnelli S, Cepollaro C, Montagnani A, et al. Heel ultrasonography in monitoring alendronate therapy: a four year longitudinal study. Osteoperos Int. 2002; 13(5): 415-421.
9. Harris ST, Watts NB, Genant HK, et al. Effects of risedronate treatment on vertebral and nonvertebral fractures in women with postmenopausal osteoporosis: a randomized controlled trial. Vertebral Efficacy with Risedronate Therapy (VERT) Study Group. JAMA. 1999; 282(14): 1344-1352.
10. Johnell O, Kanis JA, Oden A, et al. Predictive value of BMD for hip and other fractures. J Bone Miner Res. 2005; 20(7):1185-1194.
11. Jorgensen HL, Warming L, Bjarnason NH, et al. How does quantitative ultrasound compare to dual x-ray absorptiometry at various skeletal sites in relation to the WHO diagnosis categories? Clin Physiol. 2001; 21(1):51-59.
12. Kanis JA, Borgstrom F, De Laet C, et al. Assessment of fracture risk. Osteoporos Int. 2005; 16(6):581-589.
13. Kullenberg R, Falch JA. Prevalence of osteoporosis using bone mineral measurements at the calcaneous by dual X-ray and laser (DXL). Osteoporosis Int. 2003; 14(10):823-827.
14. Miller PD, Zapalowski C, Kulak CA, et al. Bone densitometry: the best way to detect osteoporosis and to monitor therapy. J Clin Endocrinol Metab. 1999; 84(6):1867-1871.
15. Nairus J, Ahmadi S, Baker S, et al. Quantitative ultrasound: an indicator of osteoporosis in perimenopausal women. J Clin Densitom. 2000; 3(2):141-147.
16. Picard D, Brown JP, Rosenthall L, et al. Ability of peripheral DXA measurement to diagnose osteoporosis as assessed by central DXA measurement. J Clin Densitom. 2004; 7(1):111-118.
17. Stewart A, Reid DM. Precision of quantitative ultrasound: comparison of three commercial scanners. Bone. 2000; 27(1):139-143.
18. Thomas E, Richardson JC, Irvine A, et al. Osteoporosis: what are the implications of DEXA scanning 'high risk' women in primary care? Fam Pract. 2003; 20(3):289-293.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Association of Clinical Endocrinologists (AACE) and American Association of Endocrine Surgeons (AAES) position statement on the diagnosis and management of primary hyperparathyroidism. AACE/AAES Task Force on Primary Hyperparathyroidism. Am J Gastroenterol. 2005; 11(1):49-54. Available at: https://www.aace.com/sites/default/files/HyperparathyroidPS.pdf. .  Accessed on September 21, 2011
2. American Association of Clinical Endocrinologists (AACE). Medical guidelines for clinical practice for the diagnosis and treatment of postmenopausal osteoporosis. Endocr Pract. 2010; 16(Supl 3):1-37. Available at: https://www.aace.com/sites/default/files/menopause.pdf.  Accessed on September 21, 2011.  
3. American Association of Clinical Endocrinologists (AACE) Medical guidelines for clinical practice for the prevention and treatment of postmenopausal osteoporosis: 2001 Edition, with Selected Updates for 2003. Endocr Pract. 2003; 9(6):544-564.
4. American College of Obstetrics and Gynecology. Committee opinion No. 270. Bone density screening for osteoporosis. Obs Gynecol. 2002; 99(3):523-525.
5. Blue Cross and Blue Shield Association. Ultrasonography of peripheral sites for selecting patients for pharmacologic treatment for osteoporosis. TEC Assessment, 2002; 17(5).
6. Centers for Medicare and Medicaid Services. National Coverage Determination for Bone (Mineral) Density Studies. NCD #150.3. Effective July 1, 1998. Available at: http://www.cms.hhs.gov.  Accessed on September 21, 2011.
7. Management of osteoporosis in postmenopausal women: 2010 position statement of The North American Menopause Society. Menopause. 2010; 17(1):25-54. Available at: http://www.menopause.org/psosteo10.pdf. Accessed on September 21, 2011.
8. National Institute of Health (NIH). Osteoporosis prevention, diagnosis, and therapy. NIH Consensus Statement. 2000; 17(1):1-45. Available at http://consensus.nih.gov/2000/2000Osteoporosis111PDF.pdf .  Accessed on September 21, 2011.
9. National Osteoporosis Foundation. Clinician's guide to prevention and treatment of osteoporosis. Updated January 2010.  Available at: http://www.nof.org/professionals/clinical-guidelines.  . Accessed on September 21, 2011.
10. U.S. Preventive Services Task Force (USPSTF). Screening for osteoporosis in postmenopausal women. a review of the evidence for the U.S. Preventive Services Task Force. Annals of Internal Medicine. 2002; 137(6):529-541.  Available at http://www.annals.org/content/137/6/529.full.  Accessed on September 21, 2011.

Bone Mineral Density Measurement
Dual-Energy X-Ray Absorptiometry (DEXA)
Osteoporosis