<prompt> Histology from a bone biopsy from proximal femur is given below of a 50 year old with bone pain. What is your diagnosis?OsteomalaciaPagets diseaseOsteoporosisOsteosclerosis  <response>: Ref. Robbins Pathology. 9th edition. Page. 1191 Paget DiseaseDiagnostic features are increased osteoclastic and osteoblastic activity with supportive radiologic findingsAcute: primarily woven bone; focal mosaic pattern of lamellar bone, resembles jigsaw puzzle with prominent irregular cement lines; osteoclasts present at surface of bone but dont tunnel; in osteolytic phase, osteoclasts may have up to 100 nucleiChronic: thick trabeculae and thicker bones; fine fibrosis of marrow Osteosclerotic stageThe picture is also known as mosaic pattern of bone 