Bone density (DEXA): the 10-minute exam most people put off

# Bone density (DEXA): the 10-minute exam most people put off

*A very low dose X-ray measures the bone in your spine and hip while you lie still. What it is for, what to wear, and which four centers do it.*

October 12, 2026 · Desert Imaging

Of all the exams we do, this is the one people describe afterward as "that was it?" You lie on a padded table. An arm passes slowly over your lower back and then your hip. Nothing touches you, there is no injection, and you are done in about 10 minutes. It is also the exam that gets put off for years, because nothing hurts and the appointment never feels urgent.

## What it measures

A bone density test, DEXA for dual energy X-ray absorptiometry, uses a very low dose X-ray to measure how much mineral is in your bones. The dose is tiny, about the same as a flight from El Paso to Los Angeles.

The scan measures the lower spine and one hip. Those are the sites with the most spongy bone, where osteopenia, which is slight bone loss, and osteoporosis, which is porous bone, show earliest. They are also the best places to check whether a treatment your doctor prescribed is working, which is why the test is often repeated.

A bone density test measures bone strength. It does not show fractures the way an X-ray does, so your doctor may order both.

At West we also do vertebral fracture assessment, a side view of the spine on the same machine that checks for compression fractures. Body composition, which measures fat and lean mass, is available as a self-pay exam.

## Where to go

Bone density is done at four of our centers: West on Castellano, East on Lee Trevino, Joe Battle, and Horizon City. All four are open Saturdays. The scanners are Hologic Discovery systems, the same at every center that offers it, and the same system rides on two mobile units.

## Getting ready

There is very little to it.

- Wear loose clothing with no metal or plastic fasteners. Elastic waistbands are ideal. Zippers, buttons, snaps and underwire can land over the spine or hip and get in the way of the picture.
- Do not take calcium supplements for 24 hours before the exam. Calcium tablets take time to dissolve. If one is still in your stomach or bowel over the spine, it can read as bone and make the result look better than it is.
- Vitamin D and all your other medication are fine. Take them as usual.
- Eat and drink normally.

If your last scan was somewhere else, tell us when you book. The radiologist will want to compare.

## The exam itself

You lie on your back on a padded table. The scanner arm passes slowly over your spine, then over your hip. You hold still, which is easy, because there is nothing to feel and nothing to hear. Both measurements together take about 10 minutes.

Is it painful? No. Nothing touches you and there is no injection.

## The order

Bring your doctor's order. It tells us whether to scan the spine, the hip or both, and most insurance plans require it for the exam to be covered. If your doctor has mentioned a bone density test and you have not booked it, that order is the only thing standing between you and a 10-minute appointment.

## Afterward

A board-certified radiologist reads the scan. The report goes to your doctor and to your patient portal.

Your doctor decides what the result means for you and how often to repeat the test, based on your result, your age and any treatment you are on. The radiologist describes the bone. Your doctor puts it in the context of you.

## Why people put it off, and why not to

There is no symptom that sends you to this exam. Bone loss does not hurt until something breaks. That is exactly why the test exists: to measure what you cannot feel, while your doctor can still do something about it.

Ten minutes, loose clothes, no calcium that morning. Four centers, open Saturdays. That is the whole thing.