A DEXA scan of the lumbar spine is a low‑radiation X‑ray test that measures bone mineral density in the lower back. It helps diagnose osteoporosis or osteopenia, estimates fracture risk using T and Z scores, and monitors response to treatment. The scan is quick, noninvasive, and commonly recommended for older adults or people with risk factors for bone loss.

A DEXA scan typically measures bone density at three key sites: the lumbar spine (L1–L4), the hip (total hip and/or femoral neck), and the forearm (distal radius/one‑third radius). These sites reflect common fracture locations and provide standardized values for diagnosing osteoporosis and monitoring treatment response. Scans are quick, noninvasive, and interpreted using T‑scores.

A DEXA scan measures bone mineral density and can detect osteoporosis and vertebral compression fractures or deformities, especially with lateral vertebral assessment. It cannot evaluate discs, nerves, muscles, or most causes of typical back pain. If DEXA suggests bone loss or fracture, or if symptoms persist, further imaging (X‑ray, CT or MRI) and clinical assessment are needed to identify other spinal problems.

A normal lumbar spine DEXA is when the composite T-score for L1–L4 is −1.0 or higher. T-scores between −1.0 and −2.5 indicate low bone mass (osteopenia), and −2.5 or below indicates osteoporosis. For premenopausal women, men under 50 and children, Z-scores are used; a Z-score ≤ −2.0 is considered below the expected range for age.

A doctor may recommend a DEXA scan to measure bone mineral density and diagnose osteoporosis or osteopenia, estimate fracture risk, and establish a baseline before or during treatments (such as long-term steroids or osteoporosis medications). It’s also used to monitor treatment response, evaluate unexplained low‑trauma fractures, and sometimes assess body composition (lean vs. fat mass) for clinical management.

In India, a DEXA (bone mineral density) scan typically costs between ₹800 and ₹4,000, with metropolitan private diagnostic centers charging about ₹1,200–₹4,000 and smaller clinics or government hospitals offering lower rates (often ₹800–₹1,500). Prices vary by city, facility, body sites scanned, and whether reporting/consultation is included — confirm exact fees when booking.