Musculoskeletal Imaging Normal radiological representation Structure of bone

Musculoskeletal Imaging

Normal radiological representation

Structure of bone and cartilage

Epiphysis Epiphysial line Diaphyses

Basic pathologic changes

Basic Pathologic Changes Osteoporosis n osteomalacia n Osteosclerosis n Periosteal new bone formation n Sequestrum n

Osteoporosis n Definition: n Osteoporosis is a common metabolic disorder of bone characterized by qualitatively normal but quantitatively deficient bone

The representatio n of osteoporosis

Osteoporosis n Classificaton: It can be divided into generalized, regional， and localized types and accompanies a variety of disease processes

Osteoporosis n Pathophysiology Condition accounting for reduced bone density , however, the quantity of bone is deficient but the quality is normal n The normal equilibrium between the rate of bone formation and resorption is lost with resorption predominating n

Osteoporosis n Cause of a disease(in child): Generalised osteoporosis n osteogenesis imperfecta n acute leukaemia n chronic systemic disease, e. g. cystic fibrosis n nutritional causes n storage disorders

Osteoporosis n Cause of a disease(in child): Localised osteoporosis n disuse (e. g. immobilisation post fracture) n atrophy n idiopathic juvenile osteoporosis n AV malformation n previous irradiation therapy

Osteoporosis n Cause of a disease(in adult): n Generalized osteoporosis n age-related accompanied endocrine disorders n Pregnancy n alcoholism n n Involvement of the axial skeleton and proximal portions of the long bones

Osteoporosis n Cause of a disease(in adult): n Regional osteoporosis disuse or immobilization n transient osteoporosis of the hip n regional migratory osteoporosis n n Changes predominate in the appendicular skeleton.

Osteoporosis n Radiographic manifestation The vertebral bodies may develop a biconcave shape or compression fractures n In tubular bones the trabecular bone loss may cause the metaphyses to appear radiolucent n Pathological fractures may occur at multiple sites n Schmorls nodes n acute and insufficiency fractures n

Osteoporosis n MR imaging in transient osteoporosis of the hip manifested as decreased signal intensity on T 1 -weighted sequences and increased signal intensity on T 2 weighted sequences n The patient commonly has associated joint effusions in the affected hip n Chemical shift fat suppression and STIR imaging techniques can be effective in the detection of transient bone marrow oedema n

How to prevent it ? Milk and physical exercise

Osteomalacia Definition: n Osteomalacia is a group of disorders resulting from inadequate or delayed mineralization of osteoid in mature cortical and spongy bone n

Osteomalacia n Pathophysiology : n Osteomalacia is characterized by abnormal quantities of osteoid coating the surfaces of trabeculae and lining the haversian canals in the cortex (osteoid seams)

Osteomalacia n Cause of a disease Deficienty of vitamin D n Gastrointestinal malabsorption n Metabolic bone disease of premature infants n Liver disease (hepatic osteodystrophy ) n Drug therapy n Renal osteodystrophy n Tumor-associated osteomalacia n

Osteomalacia n Radiographic manifestation n Loosers zones or Milkmans pseudofractures are strongly suggestive but not diagnostic of osteomalacia

Osteomalacia AP radiograph of the hip demonstrates generalized osteopenia and a linear lucency (representing a Looser's zone) in the medial cortex of the femur.

Osteomalacia - Back Pain Condition n n n Osteomalacia is one of many conditions that can cause back pain. it is one of the first recognizable symptoms If your body doesn’t have enough vitamin D ，that can bring about osteomalacia This condition causes your bones to become softer over time Your bones may even start to bend under the pressure of your own body weight The type of back pain associated with osteomalacia is pain along your spinal column

Osteosclerosis n Definition: n Osteosclerosis is an abnormal hardening or increased density of bone on radiographs

Osteosclerosis n Cause of a disease: hyperparathyroidism n renal osteodystrophy n osteoarthritis n skeletal metastasis n myelofibrosis n osteomyelitis n

Osteosclerosis n Location of disease n In renal osteodystrophy n n the axial skeleton is the dominant site of involvement; the pelvis, ribs and spine are affected most commonly Osteosclerosis n the vertebral bodies produces changes at both superior and inferior aspects, leading to an appearance termed the rugger jersey spine

Osteosclerosis n Radiographic manifestation n Increased radiodensity of bone that may occur with various conditions including renal osteodystrophy, osteopetrosis and pyknodysostosis

Osteosclerosis n Renal osteodystrophy is a general term used to describe the bony changes associated with chronic renal disease n usually seen in late childhood n

Renal osteodystrophy The radiographic changes n apparent physeal widening (representing a widened zone of provisional calcification) n metaphyseal flaring, cupping and irregularity n

üRenal osteodystrophy üOsteopenia, üsubcortical resorption, ülucent metaphyseal bands, ü widening of metaphysis

Renal osteodystrophy Thinning of cortices

Renal osteodystrophy n The radiographic changes： n the radiographic features of secondary hyperparathyroidism ： n focal areas of subperiosteal bone resorption and osteopenia n Common sites of involvement include the radial aspect of the phalanges, distal radius, distal clavicle, symphysis pubis and lateral aspect of the femoral neck

üRenal osteodystrophy ü Radiograph of both hands demonstrating diffuse increased bone density ücoarse trabecular pattern and subperiosteal new bone formation üparticularly involving the medial aspect of the middle phalanges and distal radius and ulna

Renal osteodystrophy n The radiographic changes： n the radiographic features of secondary hyperparathyroidism ： n Osteosclerosis of the vertebral end plates may cause a "rugger jersey" spine. n Ectopic calcification n slipped epiphyses particularly the capital femoral epiphysis

“rugger jersey" spin

"rugger jersey spine"

Renal osteodystrophy n The radiographic changes： the radiographic features of secondary hyperparathyroidism： n In severe long-standing cases brown tumor may develop, these are rounded lucencies with indistinct margins seen particularly within the pelvis or long bones n

üRenal osteodystrophy üKnee radiograph demonstrating a Brown tumor in the proximal right fibular metaphysis

Renal osteodystrophy n Conclusion of radiography: n Early - Osteopenia n Thinning of cortices and trabeculae gives "ground glass" x-ray n Salt and pepper skull n Physeal thickening n Late epiphyseal ossification n Epiphyseal Slips - Preschool age: Proximal and distal femoral and distal tibial

Renal osteodystrophy n Conclusion of radiography: n Late - Secondary hyperparathyroidism n Subperiosteal cortical resorption - Distal phalanx, end of clavicle, pubis n Lucent metaphyseal bands - are the best indicator of severity n Bowing of long bones n Rugger Jersey spine - Osteosclerosis of the end plates of the vertebral bodies n Brown Tumor (rare)

Osteopetrosis is a thymic defect n The result is generalised osteosclerosis with dense, thick, brittle bones. n

Osteopetrosis n Radiographic appearance: n most marked with generalized osteosclerosis, cortical thickening, loss of normal corticocancellous differentiation and obliteration of normal trabecular pattern

Osteopetrosis a. Right lower leg, b, pelvis and femora, c. lateral spinal radiograph Note the marked sclerosis of the bones and pathological fracture in the fibula.

Osteopetrosis

Pyknodysostosis Definition: Pyknodysostosis is a dysplasia manifest clinically by dwarfism, increased bone fragility and sclerotic bones It is a syndrome chararacterized by osteosclerosis, short stature, short broad hands

Pyknodysostosis Radiological appearance: n a widely open persistent anterior fontanelle 。 The angle of the mandible is very obtuse with severe micrognathia n The vertebral bodies and long bones are sclerotic and with narrowing of the medullary canals n

Pyknodysostosis Lateral skull radiograph showing sclerosis of the skull. Both fontanelles are open.

Pyknodysostosis Radiograph of the lower limbs with very dense bones and fractures.

Periosteal new bone formation Definition： n Periosteal new bone formation is a nonspecific response of the periosteum to a variety of causes; it may be focal or diffuse n

Periosteal new bone formation Cause： n physiological, congenital, infective, inflammatory, traumatic, metabolic, neoplastic n

Periosteal new bone formation a spiculated "sunburst" pattern with undercutting of the margins (Codmans triangle) suggests a primary bone malignancy; n a laminated "onion skin" pattern can be seen with an aggressive lesion n

Periosteal new bone formation Following trauma, focal periosteal new bone formation may be seen radiographically at 5~14 days n The exact timing is dependent on the age of the child (earlier in the younger child, later in the older child) n

Periosteal new bone formation in non accidental injury is often more extensive than in accidental trauma n In non-accidental injury periosteal new bone formation can also occur in the absence of fractures n

Periosteal new bone formation n Periosteal new bone formation may be the only radiographic evidence of a stress fracture and occurs at the site of deforming force

Periosteal new bone formation There is periosteal new bone in the tibial diaphysis secondary to a healing spiral fracture. The endosteal cortical thickening on the tibia medially

new bone formation Axial CT image of the proximal tibia demonstrating periosteal new bone on the posteromedial aspect secondary to a healing stress fracture.

Periosteal new bone formation （Radiograph of the humerus） in a child with a Ewing's sarcoma demonstrating spiculated sunburst periosteal new bone formation.

Sequestrum is a fragment of necrotic bone that becomes separated from healthy bone n Sequestra may occur in various conditions, such as osteomyelitis, tuberculous arthritis n

Sequestrum radiographs of the femur demonstrate a healed fracture of the femoral diaphysis. A large rod-like sequestrum is observed in the medullary canal owing to chronic osteomyelitis

Sequestrum In haematogenous osteomyelitis, a sharply marginated bone lesion is seen as radiodense bone spicules caused by osseous necrosis n The sequestrum frequently lies in a space surrounded by granulation tissue n

Sequestrum In some cases the sequestrum may break through the cortex and enter the soft tissues, sometimes being discharged through draining sinuses n Sequestra are best visualized using conventional tomography, CT scanning n