Irregular Metaphyses

Rickets Ray
Fig. 5.56. X-linked hypophosphatemic rickets in a 2-year-old boy. There is poor mineralization of the metaphyseal regions, with a coarse (malacic) bone texture. The metaphyses show mild fraying, cupping, and widening

► [Coarse, frayed, disorganized metaphyses with edge indistinctness]

As anticipated above in the section "Metaphyseal Cupping," marked changes around the metaphyses, including undermineralization of the provisional zone, widening, cupping, and fraying, are characteristic features in rickets, X-linked hypophosphatemia (familial vitamin D-resistant rickets, OMIM 307800) (Fig. 5.56), and hypophosphatasia (OMIM 241500, 146300) (Fallon et al. 1984). Extensive metaphyseal changes occur in the conditions grouped together under the designation of metaphyseal chondrodysplasia. Histological findings are nonspecific and similar in all the metaphyseal chondrodysplasias, consisting in disorganized arrangement of the cartilage cells in the growth plate with retarded endochondral bone formation. In metaphyseal chondrodysplasia, Jansen type (OMIM 156400), a rare autosomal dominant dwarfing disorder with joint swelling and bowing of legs and forearms, metaphyseal changes vary according to the patient's age. In infancy, mild metaphyseal irregularities in the short and long tubular bones are seen. In childhood, severe metaphyseal

Taphysaire Jansen

Fig. 5.57 a, b. Metaphyseal chondrodysplasia, Jansen type in a boy. a In the neonatal period only mild metaphyseal irregularities are seen. The bones are undermineralized. b In images taken when the boy was 7 years old severe metaphyseal changes have developed, with metaphyseal widening, cupping, and a typical coarse pattern of dense areas interspersed with areas of increased radiolucency. The epiphyses are grossly normal, and are widely separated from corresponding metaphy-ses. (From Giedion 1994)

Fig. 5.57 a, b. Metaphyseal chondrodysplasia, Jansen type in a boy. a In the neonatal period only mild metaphyseal irregularities are seen. The bones are undermineralized. b In images taken when the boy was 7 years old severe metaphyseal changes have developed, with metaphyseal widening, cupping, and a typical coarse pattern of dense areas interspersed with areas of increased radiolucency. The epiphyses are grossly normal, and are widely separated from corresponding metaphy-ses. (From Giedion 1994)

f %
Spondyloenchondromatosis
Fig. 5.58. Metaphyseal chondrodysplasia, Schmid type in a 3-year-old girl. The femurs are bowed, with relatively dense diaphyses. The metaphyses are irregularly ossified, with fraying and splaying. The growth plates are wide, with normal epi-physes

cupping, irregular calcification, and fragmentation occur (Fig. 5.57a,b). Scattered foci of irregular calcification are interspersed with radiolucent areas of unossified cartilage. In adults,most of the roentgeno-graphic changes about the metaphyses improve, while leaving severely short and bowed limbs with expanded metaphyses (Charrow and Pznanski 1984). The autosomal dominant metaphyseal chondrodysplasia, Schmid type (OMIM 156500) usually manifests after infancy. The radiographic pattern, which is remarkably similar to that in X-linked hypophos-phatemic rickets, includes diffuse metaphyseal flaring, irregularity, and growth plate widening, which are most severe in the knees (Gellis et al. 1980) (Fig. 5.58). Unlike the pattern in vitamin-D resistant rickets, however, the metaphyses are well mineralized. The hands are not affected, while the vertebrae are only occasionally involved. [The observation of a possible spinal involvement in metaphyseal chon-

drodysplasia has led Savarirayan et al. (2000) to conclude that Schmid metaphyseal chondrodysplasia and spondylometaphyseal dysplasia, Japanese type, are identical conditions.] The autosomal recessive metaphyseal chondrodysplasia, McKusick type (cartilage hair hypoplasia, OMIM 250250) is characterized by striking metaphyseal abnormalities in the tubular bones, most prominent at the knees, with flaring, cupping, scalloping, marginal serration, and fragmentation. Irregular cyst-like radiolucencies extending from the metaphyses into the diaphyses are also present. Epiphyses are only mildly affected (McKusick et al. 1965). Greater involvement of the metaphyses at the knees and less prominent coxa vara and bowed legs are useful radiologic criteria that can be applied to differentiate McKusick type from Schmid type metaphyseal chondrodysplasia. Moreover, the metaphyses of the metatarsals, meta-carpals, and phalanges are also affected. Metaphyseal chondrodysplasia, Shwachman-Diamond type (OMIM 260400) is a short-limbed dwarfism of autosomal recessive inheritance, which is characterized by failure to thrive, malabsorption related to exocrine pancreatic insufficiency, blood cell diminution (leuko-penia, neutropenia, thrombocytopenia), recurrent infections, and ectodermal dysplasia. Metaphyseal changes are discrete, predominate at the levels of the hips and knees, and consist of alternating sclerotic and radiolucent areas, which may eventually appear radiographically as metaphyseal vertical striations (McLennan and Steinbach 1974). Metaphyseal ana-dysplasia (OMIM 309645) is another metaphyseal bone dysplasia, characterized by early-onset, severe metaphyseal changes that regress spontaneously over time with complete restoration of the normal bony structure (Wiedemann and Spranger 1970; Maro-teaux et al. 1991). The favorable course is the distinguishing feature of this disorder. Patients' final height is normal. The metaphyseal alterations include irregularities, widening, and marginal blurring and are most prominent in the proximal femurs (Fig. 5.59 a,b). The long bones of the upper limbs are far less commonly involved. The epiphyses are spared. Most of those affected are male. The inheritance pattern is unknown, X-linked dominant or autosomal dominant transmission being likely (Slama et al. 1999). Severe combined immunodeficiency (SCID) with adenosine deaminase (ADA) deficiency (OMIM 102700) may show mild metaphyseal changes,includ-ing flaring and irregularities, sometimes in the shape of lateral spurs. Histological findings include lack of organized cartilage columnar formation, large lacunas with hypertrophied cells, and lack of trabecular

Spondyloenchondromatosis

Fig. 5.59 a,b. Metaphyseal anadysplasia in a 4 1/2-month-old girl. a Note severe metaphyseal alterations with widened,irreg-ularly sclerotic proximal femoral metaphyses, and markedly short femoral necks. b Similar metaphyseal abnormalities are evident at the knee and ankle. There is also mild bowing of the long bones. These abnormalities had disappeared completely on follow-up X-rays (not shown). (From Slama et al. 1999)

Fig. 5.59 a,b. Metaphyseal anadysplasia in a 4 1/2-month-old girl. a Note severe metaphyseal alterations with widened,irreg-ularly sclerotic proximal femoral metaphyses, and markedly short femoral necks. b Similar metaphyseal abnormalities are evident at the knee and ankle. There is also mild bowing of the long bones. These abnormalities had disappeared completely on follow-up X-rays (not shown). (From Slama et al. 1999)

formation. These changes are distinctly different from those observed in the metaphyseal chondrodys-plasias or in other chondrodystrophies (Cederbaum et al. 1976). The association of metaphyseal irregular-

Metaphyseal Dysplasia Schmid
Fig. 5.60. Osteoglophonic dysplasia in an 11-year-old boy.Note multiple, large metaphyseal nonossifying fibromata extending into the diaphysis. The epiphyses are small and flattened. The knee joint space is widened. (From Azouz et al. 1997)

ities and flaring, most prominent in the forearm, thickened dorsum sellae, and wedged vertebrae delineates the condition known as metaphyseal-sella turcica dysplasia (Rosenbaum and Lohr 1986). Varying degrees of metaphyseal and spinal involvement, from minimal to severe, are seen in spondylometa-physeal dysplasia, Kozlowski type (OMIM 184252). Changes include metaphyseal irregularity, widening, and sclerosis, and platyspondyly with spinal malalignment (Kozlowski et al. 1980). Among the several types of spondyloepimetaphyseal dysplasias the autosomal recessive spondyloepimetaphyseal dysplasia, Irapa type (OMIM 271650), displays widespread metaphyseal irregularities and widening, but the proximal femur and distal humerus are most prominently affected. Epiphyses appear later than expected and are small and irregular. Platyspondyly is generalized. Early-onset osteoarthritic changes of severe degree are seen around the major joints (Hernandez et al. 1980). In spondyloepimetaphyseal dysplasia, Strudwick type (OMIM 184250), changes in infancy are mainly those related to the epiphyseal component of dysplasia. Metaphyseal changes, which are less obvious in infancy, become more prominent by early childhood, with irregularities, fragmentation, and alternating sclerotic and radiolucent areas (mottling or dappling). The distal ulna is more severely affected than the radius, and the proximal fibula more than the tibia. Severe platyspondyly can be observed at all ages (Anderson et al. 1982). A peculiar type of meta-physeal involvement is encountered in osteoglophon-ic dysplasia (OMIM 166250), a dwarfing disorder of

Shwachman Diamond Dysplasia

Fig. 5.61 a-d. Spondyloenchondromatosis. a In a 2-year-old girl spondyloenchondromatosis associated with D-2-hydrox-yglutaric aciduria. Note gross metaphyseal abnormalities, with splaying columns of ossification alternating with islands of unossified cartilage resembling enchondromata. b-d. A boy examined at b 1 1/2 years, c 2 1/2 years, and d 9 years of age:

there are enchondromas in the distal femoral and proximal fibular metaphyses,which move further into the diaphyses and become sclerotic at between the ages of 1 1/2 and 2 1/2 years. By 9 years of age, the enchondromas have disappeared, leaving marked striation of the femoral and tibial metaphyses. [From Talkhani et al. 2000 (a) and Uhlmann et al. 1998 (b-d)]

Fig. 5.61 a-d. Spondyloenchondromatosis. a In a 2-year-old girl spondyloenchondromatosis associated with D-2-hydrox-yglutaric aciduria. Note gross metaphyseal abnormalities, with splaying columns of ossification alternating with islands of unossified cartilage resembling enchondromata. b-d. A boy examined at b 1 1/2 years, c 2 1/2 years, and d 9 years of age:

there are enchondromas in the distal femoral and proximal fibular metaphyses,which move further into the diaphyses and become sclerotic at between the ages of 1 1/2 and 2 1/2 years. By 9 years of age, the enchondromas have disappeared, leaving marked striation of the femoral and tibial metaphyses. [From Talkhani et al. 2000 (a) and Uhlmann et al. 1998 (b-d)]

the rhizomelic type that is characterized by clover-leaf deformity of the skull, frontal bossing, hypertelorism, craniostenosis, fibrous dysplasia of the mandibular ramus, platyspondyly, and gross dysplas-tic changes in the metaphyses, with irregular areas of radiolucency (fibrous cortical defects and nonossify-ing fibromata) (Beighton et al. 1980) (Fig. 5.60). Radi-olucent defects in the metaphyses, extending into the diaphyses, are also seen in enchondromatosis (Ollier disease, OMIM 166000). These radiolucent areas can be elongated, oval, or round, and they correspond to masses of unossified cartilage. The distribution can be either unilateral or bilateral, and the bones involved are sometimes markedly short. Adjacent epiphyses are usually hypoplastic and irregular (Mainzer et al. 1971). Enchondromatous changes in the metaphyses of the long and flat bones are also found in spondylo-enchondro-dysplasia (OMIM 271550), a very rare autosomal recessive disorder in which short stature and severe platyspondyly with endplate irregularities are further features (Schnorr et al. 1976). The enchondroma-like lesions sometimes disappear with time (Uhlmann et al. 1998) (Fig. 5.61 a-d).

Patients undergoing iron chelation therapy with deferoxamine may show metaphyseal changes, especially about the knees and wrists, consisting in meta-

physeal widening, cupping, fraying, and cystic changes of the subchondral bone.

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Responses

  • daisy
    Can metaphyseal chondrodysplasia jansen type only present in the distal femur?
    3 years ago

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