A 39-year-old woman presented with symptoms of pain in the lumbar region an
d lower extremities. Physical findings included restricted movement of the
lumbar spine, sacroiliac joint tenderness, positive Schober's test (10-12.5
cm), and bilaterally positive Mennel and Fabere tests. Although these symp
toms and findings were suggestive of ankylosing spondylitis, osteomalacia w
as diagnosed with the appearance of multiple pseudofractures in her pelvic
X-ray and laboratory abnormalities. All her symptoms and signs resolved in
6 months with vitamin D and calcium treatment.