Case report 418

Enchondromatosis revisited: New classification with molecular basis

“…Having noted that COL2A1 mutations may result in enchondroma‐like changes [Walter et al, 2007], Nakane et al [2011] performed mutation analysis on one case who fitted the definition of dysspondyloenchondromatosis and found a single nucleotide change predicting a glycine to aspartic acid substitution in the collagen 2 molecule. Indeed, the clinical features of some of the patients reported as having dysspondyloenchondromatosis are quite suggestive of a collagen 2 disorder (e.g., the patient reported by Azouz [1987] and Patient 4 in Kozlowski et al [1994]), lending support to the notion that dysspondyloenchondromatosis is yet another variant of “type 2 collagenopathy.” As noted above, the definition “chondromatosis” is misleading also in this case, as the chondromatous changes are regressive rather than progressive and there is no abnormal proliferation of cartilage. Figure 6 shows examples of chondromatous changes seen in individuals with COL2A1 mutations.…”

“…This disorder was first described by Freisinger et al [1993] and more cases were reported the following year [Kozlowski et al, 1994]; a single case reported previously [Azouz, 1987] probably had the same condition. In retrospect, the condition does not show “segmentation anomalies,” as we apply this expression today to the consequences of a primary disturbance of the embryonic segmentation progress, such as those associated with Dll3 and MESP2 mutations.…”

“…Halal and Azouz [1991] reworked the classification proposed by Spranger and coworkers in 1978 by adding types VII to IX. Type VII was suggested by the observation of a single case [Azouz, 1987]. In retrospect, that case probably had dysspondyloenchondromatosis [Nakane et al, 2011].…”

Micromelic dwarfism with cone epiphyses, metaphyseal dysplasia, and vertebral segmentation defects

“…The metaphyseal abnormalities were more evident on the skeletal films a t 9 months and the distal metaphyses of both femora showed irregularity and distinct cupping with invagination, cone-shaping of the small epiphyseal centers. The simultaneous occurrence of involvement of spine, metaphyses, and epiphyses may categorize this observation in the complex and heterogeneous group of the spondylo-epi-metaphyseal dysplasias (SEMD), but an extensive search of reported forms gave no conclusive suggestions for a final diagnosis [Azouz, 1987;Bueno et al, 1984;Freisinger et al, 1993;Kozlowski, 1974;Maroteaux, 1995;Verloes et al, 1991;Vichi et al, 19901. In the micromelic type of SEMD (also reported as "enchodromatosis-vertebral anomalies") [Kozlowski, 19741 rhizomelic micromelia is associated with epiphysicmetaphyseal dysplasia and mild scoliosis, but there is only mild involvement of the spine with hypoplasia of thoracic vertebral bodies. In this condition hands and feet are long, facial appearance is "coarse" and the anterior fontanelle large.…”

Generalized enchondromatosis in a boy with only platyspondyly in the father

“…Radiographically there are multiple enchondromata in almost all metaphyses of the long and short tubular bones with severe involvement of the hands and feet, characteristic pelvic changes which show as a n irregular scalloped appearance of the rims of the pelvic bones, platyspondyly, and dolicocephaly. Differential diagnosis includes the other enchondromatoses with spinal involvement [Spranger et al, 1978;Lachman et al, 19901: (1) spondyloenchondrodysplasia with irregularly distributed, mostly discrete enchondromata of the long tubular bones, severe platyspondyly, and autosomal recessive inheritance [Chagnon et al, 1985;Menger et al, 1989;Schorr et al, 1976;Ziv et al, 19891; ( 2 ) enchondromatosis with irregular vertebral lesions [Spranger et al, 1978 (case l)]; (3) generalized enchondromatosis with irregular vertebral lesions, in which only moderate involvement of hands and feet, platyspondyly, hemivertebrae, and irregular lesions of the vertebral bodies are found [Azouz, 19871; (4) generalized enchondromatosis with mucopolysacchariduria with the same radiological presentation as generalized enchondromatosis, and with an unclassified type of mucopolysacchariduria [Lerman-Sagie et al, 1987;Van Creveld et al, 1971 (case l)]; and ( 5 ) enchondromatosis with concave vertebral bodies [Sauvegrain et al, 1980 (cases 4 and 511 (Table I). The differential diagnosis also includes spondylometaphyseal dysplasia [Lachman, 19901. The somewhat asymmetric involvement of the metaphyses and of the pelvis is in favor of a chondromatous type lesion rather than metaphyseal dysplasia.…”