<prompt> Salt and Pepper pot appearance of skull is seen inHyperparathyroidismPagets DiseaseMultiple MylomaPseudo hyperparathyroidism  <response>: A HyperparathyroidismHYPERPARATHYROIDISM:Uncontrolled production of parathyroid hormone causes bone mass secondary to number of osteoclasts, osteoid volume defect in mineralization, slightly number of osteoblasts.Loss of lamina dura of tooth, Pepper pot appearance in skull, Rotting fence post appearance of proximal femur in childrenBone Resorption: Subperiosteal most constant specific finding; virtually Pathognomonic of Hyperparathyroidism.Lacelike irregularity of cortical margin; may progress to scallopingspiculation pseudoperiostitis, involves phalangeal tufts earliest involvement, radial aspect of middle phalanx of 2nd 3rd finger beginning in proximal metaphyseal region early involvementSubchondral collapse of cortical bone overlying cartilage with development of erosion, cyst, joint narrowing.Cortical resorption, trabecular resorption, subligamentous bone resorption.Bone Softening: Basilar impression of skull, Wedged vertebrae, kyphoscoliosis, biconcave vertebral deformities, bowing of long bones, Slipped capital femoral epiphysis.Brown Tumor: Eccentric, cortical frequently solitary expansile lytic wellmarginated cystlike lesion, endosteal scalloping, seen in jaw, pelvis, rib, metaphyses of long bones femur, facial bones, axial skeleton DDx--GCT.Osteosclerosis - Rugger jersey spine - sclerosis of vertebral endplates with intervening normal osseous densitySoft-Tissue Calcification: Metastatic calcification cornea, viscera lung, stomach, kidney, periarticular in hip, knee, shoulder, wrist chondrocalcinosis in menisci, wrist, shoulder, hip, elbow.Erosive Arthropathy, Periosteal New-Bone Formation.Sequele Hyperparathyroidism 1. Renal stones nephrocalcinosis 2. osteoblastic activity--osteitis fibrosa Cystica, brown tumours primary Hyperparathyroidism bone softening fractures, 3. Peptic ulcer disease, 4. Calcific pancreatitis, 5. Soft-tissue calcifications Secondary Hyperparathyroidism.Primary Hyperparathyroidism: Hypercalcemia due to uncontrolled secretion of parathormone by one or more hyperfunctioning parathyroid glands featuring brown tumor chondrocalcinosisSecondary Hyperparathyroidism: Diffuse adenomatous hyperplasia of all four parathyroid glands as a compensatory mechanism in any state of hypocalcemia featuring soft-tissue calcifications osteosclerosis.Tertiary Hyperparathyroidism: Development of autonomous PTH adenoma in patients with chronically overstimulated hyperplastic parathyroid glands renal insufficiency.Pseudo hyperparathyroidism: Ectopic parathormone production in paraneoplastic syndrome in bronchogenic carcinoma and renal cell carcinoma.CHARACTERISTIC X-RAY APPEARANCESSun-ray1 appearance... Osteogenic sarcomaSoap bubble appearance... OsteoclastomaMoth-eaten appearance around epiphysis... RicketsRain drop osteolytic lesions in skull ... Letterer-Siwe disease, Multiple myelomaSaw tooth appearance of metaphysis... Congenital syphilisCup and Pencil joint appearance ... Rheumatoid arthritisGround glass appearance... Fibrous dysplasiaHoneycomb appearance ... Chronic osteomyelitis, Pagets disease, Osteoclastoma, AdamantinomaCricket bat shaped ribs... Morquio diseaseRibbon ribs... NeurofibromatosisShepperd crook deformity of femur... Fibrous dysplasiaFlask shaped femur... ThalassemiaBag of bones appearance... Charcots jointsMoth eaten appearance of skull... Pyogenic osteomyelitisOnion peel appearance... Ewings sarcomaBossing of calvarium Cupping of distal... Rickets end of radius ulnaBone within a bone appearance ... Osteopetrosis, Periostitis, Scurvy, Gauchers disease congenital syphilisSwiss cheese appearance... PlasmacytomaFloating teeth appearance... HistiocytosisCelery stick of long bones in infants... Congenital rubellaBilateral iliac horns ... Nephrotic syndromePencil in cup appearance... Arthritis mutilans type of Psoriatic arthritisTrident hand is seen in... AchondroplasiaSpina ventosa air within a small bone... Tuberculous dactylitisSabre tibia... Congenital syphilisHot cross bun appearance of skull... Congenital syphilisBucket handle Epiphyseal cartilage... Battered BabyLace-work periostitis... Tertiary syphilisBayonet-like wrist... Madelungs deformityCandle wax appearance... MeliorheostosisMarble bone... OsteopetrosisWormian bones... Fibrous dysplasiaBanana fracture... Pagets diseaseEnlarged sclerotic ivory vertebra ... Pagets diseaseIvory dense vertebra ... Hodgkins lymphomaCod-fish vertebra... Hyperparathyroidism, OsteomalaciaSpoke wheel calcification within osteolytic ... Haemangioma lesion of boneSquaring of vertebral bodies ... Ankylosing spondylitisBamboo-spine appearance... Ankylosing spondylitisHair brush appearance of skull... HyperparathyroidismGeographical appearance of skull... Hand-Schuller Christian 