In the second the resorption has gone through the trabecula making a hole. This stain turns acid phosphatase red. The patient had osteitis fibrosis and an unusually large number of osteoclasts. A photomicrograph of a biopsy from my iliac crest when I was a fellow and we needed some normal controls. A photomicrograph of a biopsy from a normal postmenopausal woman showing an osteoid seam of normal width.
Mineralized bone is green and osteoid is orange.
The orange-staining osteoid covers many surfaces and is thicker than normal. The second photo is from part of the biopsy that was decalcified and thus it appears normal. The osteomalacia cannot be appreciated. Both photos from the same section of a bone biopsy. Near the cortex is osteomalacia.