Australas Radio1 1992; 36: 238-242
Cleido-cranial Dysostosis - Skeletal Abnormalities S.K. GUPTA, M.D., F.A.M.S.,F.R.C.R.,O.P. SHARMA, M.D., M.A.M.S. S. MALHOTRA, M.B .B.S., AND SANJAY GUPTA, M.B.B.S., M.D., D.N.B.E. Department of Diagnostic Radiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India.
INTRODUCTION Based on a study of seven cases, a wide spectrum of skeletal abnormalities in cleido-cranial dysostosis is presented, with the emphasis on less commonly reported observations. A few new features are also reported. Changes in the skull consisted of thickening of the squama of the-temporal bone, a rectangular configuration of the calvaria seen on computed tomography and flattening of basiocciput without basilar invagination, hypoplasia of the mastoids and persistence of the fissure at the posterior margin of the foramen magnum. Ribs showed hypoplasia and aplasia. The terminal tufts of the phalanges in one case had totally disappeared. In another case a transverse fissure divided the terminal phalanges of both index fingers. In a further case, bilateral bifid patellae were present. DISCUSSION AND LITERATURE REVIEW Classical features of cleido-cranial dysostosis include absence of all or part of one or both clavicles, brachycephaly and delay in closure of fontanelles and sutures. From the report of Jarvis and Keats (l), who published the largest single series of 40 affected individuals in 8 unrelated families, i t is obvious that the syndrome involves virtually the entire skeleton. A broad spectrum of skeletal abnormalities in this condition is also reported by other workers (2,3).
Key words: Cleido-cranial dysostosis s k e h n l abnormalities Add 'cs for correspondence: Dr 5 . ~Gupta . 2 G.k., Old Medical Enclave Banuras Hindu University Varanasi 22 1 005 Indi:i
238
FIGURE 1 -Lateral SXR showing thickening of squama of temporal bone.
We have come across 7 sporadic cases of cleido-cranial dysostosis, two of which have already been published (3, 4) as single case reports. The purpose of this paper is to review the skeletal abnormalities with the emphasis on less commonly reported observations and also to present some new features. These are a rectangular configuration of the cranial vault seen on CT scan, hypoplasia of ribs, resorption and absence of terminal phalanges, transverse fissuring of the terminal phalanx of the index finger and additional centres of ossification of the patella. Familiar components of cleido-cranial dysostosis are brachycephaly, wide interparietal diameter, hypertelorism, open frontal fontanelle and suture, numerous wormian bones, delayed suture closure, aplasia of clavicles and hereditary transmission (5). Both dominant and recessive inheritance of cleido-cranial dysostosis has been reported and there are occasional sporadic cases (6, 7). All our patients fall into the category of sporadic cases and are explained by genetic muta-
tions. The parents and grandparents of our patients were normal and other siblings in the family were also free from this disorder. Such random occurrences are supported by other studies of patients with normal antecendents and no reports of latency or reappearance of the disorder (6,8). The aetiology of this disease is unknown. The defect is presumably carried in the genes of affected individuals and results in developmental aberration of mesenchymal, beginning in the earliest weeks of embryonic life and producing retarded ossification of membranous and cartilaginous precursors (1). Frontal, parietal and occipital bossing is usually prominent. With the frequent concurrent depression of the sagittal suture, this has been described as the Hot Cross Bun effect (8). Less commonly noted changes are sclerosis or thickening of the squamosal portion of the temporal bone (Figure 1).
Submitted for publication on: 9th July, 1991 Resubmitted for publication on: 11th February, 1992 Accepted for publication on: 17th March, 1992
Australasian Radiology. Vol.36. No. 3. August. 1992
CLEIDO-CRANIAL DYSOSTOSIS Calvarial thickening may also involve the squama of the occipital bone above the level of the external occipital protuberance, giving rise to a squared appearance of the occiput (8). There is often flattening of the basiocciput (2) but without any evidence of basilar invagination (Figure 2). Of particular interest is the occipital and general calvarial contour showing similarities in cleido-cranial dysostosis and osteogenesis imperfecta (9). On computed tomographic examination there is rectangular (Figure 3), instead of the normal oval shaped, configuration of the calvaria, a feature not previously described. CT is not generally required to diagnose or evaluate cases of cleido-cranial dysostosis.
FIGURE 2 -Lateral SXR showing flattening of basiocciput.
RGURJZ 3 - CT Scan showing rectangular contour of calvaria and a defect in the frontal bone. Australasian Radiology, Vol. 36, No. 3 , August, 1992
Some cases of cleido-cranial dysostosis present with mixed deafness due to hypoplasia of the mastoids, poorly pneumatised temporal bones and concentric narrowing of the external auditory canals (10). One of our patients had this type of deafness. The foramen magnum may be deformed and there is often persistence of the fissure at the posterior margin of the foramen magnum (Figure 4).
FIGURE 4 - Towne's view showing a triangular defect in the posterior margin of foramen magnum.
239
S.K. GUPTA et a1 arthrosis may occur forming a false joint between the enlarged ends of clavicles lateral to the mid-portion. The sternal fragment is anterior and superior to the acromial fragment at the pseudarthrosis (1). Pressure on the brachial plexus or subclavian artery by the clavicular fragments has been reported to produce neurologic and vascular symptoms (12). Present at birth, the conical thorax remains throughout life as a distinguishing but not diagnostic mark of cleido-cranial dysostosis (13). The cone shaped thorax appears to be related to the hypoplasia or delayed development of a segment of the posterior part of a vertebral body, the resultant posterior wedging remaining in many adults as a residual deformity. Gross abnormalities in the form of hypoplasia of various degrees involving some of the left sided ribs in one of our cases appears to be a skeletal abnormality not previously described in this condition (Figure 5 ) . Faulty development of centres of embryonic vertebral arches (14) accounts for neural arch defects, hemivertebrae and posterior wedging of the thoracic spine. Spondylolysis and spondylolisthesis may also be seen. Irregular ossification of cervical vertebrae shown by the presence of multiple small osseous nuclei adjacent to the vertebral bodies and a disturbance in ossification of the bodies of dorsal and lumbar vertebrae has also been reported (2). FIGURE 5 - Postero-anterior view of chest showing absence of clavicles on both sides and variable degrees of hypoplasia of left-sided ribs.
Dental abnormalities often cause the patient to seek treatment. Dental dysplasia occurs in almost all patients manifested by delayed or failed eruption of the permanent teeth. Most of the teeth in. cleido-cranial dysostosis fail to erupt throughout adulthood ( 8 ) . Occasionally the symphysis menti remains widened. Mandibular prognathism and maxillary micrognathism have also been reported (6). Clavicular abnormalities give this disorder its characteristic appearance of drooping shoulders, an elongated
240
neck and an ability to approximate the shoulders anteriorly. This feature does not apparently interfere with the capacity to perform physical labour. Davis (1 1 ) reported a patient who because of this anomaly was able to wriggle out of any hold as a college wrestler. Clavicular abnormalities range from a small defect in one clavicle to complete absence of both. The most common deformity is the absence of the central clavicular segment with small bony stumps attached to the sternum and acromion. In approximately 10% of cases the clavicles are entirely absent. Pseud-
A troublesome defect is contraction of the pelvis making childbirth difficult. Dysplasias in the ilial and pubic bones dften narrow the maternal pelvic diameters and alter the birth canal. Hypoplasia of the iliac wings results in loss of normal ilial flaring sometimes producing vertical lateral margins. The pubic symphysis may fail to fuse and remain widened. Widening of the sacro-iliac joints gives a “see-through” appearance in some patients (1). Lateral notching of the capital femoral epiphysis may be present. Unusual ossification may produce broading of the femoral head and widening of femoral neck (3). Other abnormalities seen are coxa valga, coxa vara and irregular mineralisation of the appositional new bone in the acetabula (2, 15). Striking changes occur in the hands. The terminal tufts of the Australasian Radiology. Vol.36. No. 3, August. 1992
CLEIDO - CRANIAL DYSOSTOSIS
FIGURE 6 - X-rays of hands showing variable resorption and absence of the terminal phalanges.
phalanges show characteristic pointing and a variable degree of resorption. In one of our patients, resorption was so extensive that some of the terminal phalanges totally disappeared (Figure 6). We also observed a transverse fissure dividing the terminal phalanges of both index fingers into two parts (Figure 7). These appear to be new osseous observations.
There have been a few case reports of pahtologic fractures and concurrent osteosclerosis in cleido-cranial dysostosis (6, 16, 17), but the distribution of lesions and bone density differed from the pronounced sclerosis typical of marble bone disease. In one of our patients post traumatic fracture of the humerus occurred but there was no evidence of osteosclerosis (Figure 8).
FIGURE 8 - Antero-posterior and lateral X-ray of right humerus showing an oblique fracture of the shaft. Australasian Radiology, Vol. 36, NO.3 , August, 1992
FIGURE 7 - X-ray of hands showing linear transverse fissure dividing the terminal phalanges of index fingers.
We also noted one patient with additional centres of ossification of the patellae (Figure 9) bilaterally. Rarely there are cases with underfunnelization of the tibia1 and fibular metaphyses ( 2 ) . A rare association with cleido-cranial dysostosis is osteogenesis imperfecta and congenital pseudarthrosis of the tibia (18). Congenital femoral pseudarthrosis has also been associated (19). In a patient
FIGURE 9 - Antero-posterior X-ray of knee bipartite patella.
24 1
S.K. GUPTA et a1 with cleido-cranial dvsostosis and , ~. .~~ . . anv ..-~ ~ ~ neurologic symptoms, progressive scoliosis not responding to conservative therapy or progressive scoliosis after skeletal maturation, the presence of syringomyelia shoud be considered. The precise* pathophysiological relationship between cleido-cranial dysostosis and syringomyelia is not understood, but recognition is important for treatment (20). ~
~
~
Our knowledge of the pathogenesis of this disorder and the variety of its skeletal abnormalities is still incomplete. Further collection of case material will undoubtedly show an even broader spectrum.
3.
~
4.
5.
6. 7.
8. 9. 10.
REFERENCES 1.
2.
Jarvis J L and Keats TE. Cleidocranial dysostosis. A review of 40 new cases. Amer Jour Roentgenol 1974; 125: 5-15. Keats TE. Cleido-cranial dysostosis, some atypical findings. Amer Jour Roentgenol 1967; 100: 71-74.
242
11. 12.
Mohan V, Sharma OP, Kumar K. Srivastava TP and Gupta SK. Cleidocranial dysostosis. Ind Jour Orth 1976; 1 0 47-53. Gupta SK, Bhattacharya AK and De DC. Radiological features in cleido-cranial dysostosis. Ind Jour Radiol 1968; 22: 157-160. Marie P and Sainton P. Sur la dysotose Cleido-cranienne hereditaire Rev Neurol 1898; 6: 835-838. Forland M. Cleido-cranial dysostosis. Amer Jour Med 1962; 33: 792-199. Kochs PE and Hammar WB. Cleidocranial dysostosis. Review of literature and report of a case. J Oral Surg 1978; 36: 39-42. Soule AB. Mutational dysostosis. J Bone J Surg 1946; 28: 81-102. Campbell JA. Roentgen aspects of cranial configuration in cleido-cranial dysostosis. Rad CI N Amer 1966; 4: 11-31. Gay IS. A case of dysostosis cleido-cranialis with mixed deafness. J Pharyng and Otol 1958; 72: 915-917. Davis PL. Deafness and cleido-cranial dysostosis. Arch Otalaryng 1954; 59: 602-604. Poynton FJ, Davies HM. Case of cleidocranial dysostosis in which the removal of outer part of imperfect right clavicle relieved severe symptoms from pressure on the brachial plexus. In Proc Roy SOCMed 1914; 8: 25.
13. Miles PW. Cleido-cranial dvsostosis: survev of 6 new cases and 126 'from literaturd. J Kansas M SOC1940; 41 :462-468. 14. Arey LB. Developmental anatomy. Seventh edition. W.B. Saunders Co. Philadelphia 1965; pp 406-410. 15. Saggar RR, Nigam R. Cleido-cranial dysostosis. Ind J Med Assoc 1963; 40: 81-82. 16. Thomsen G and Guttadauro M. Cleidocranial dysostosis associated with osteosclerosis and bone fragility. Acta Radiol 1952; 37: 559-561. 17. Thorns J. Cleido-cranial dvsostosis. Report of two cases with special characteristics. Acta Radiol 1958; 50: 514-556. 18. McGinnis MR and Muller JO. Congenital pseudarthrosis of tibia associated with cleidocranial dysostosis and osteogenesis imperfecta. A case report. Clin Orth 1987; 220: 228-232. 19. Lemperg R. Cleido-cranial dysostosis. Pseudarthrosis femoris congenita. Nord Med 1963; 9: 986-988. 20. Dore DD, Mac-Ewen GD and Boulos MI. Cleido-cranial dysostosis and syringomyelia. Clin Orth 1987; 214: 229-234.
Australasian Radiology, Vol. 36. No. 3, August. 1992
Cleido-cranial Dysostosis - Skeletal Abnormalities S.K. GUPTA, M.D., F.A.M.S.,F.R.C.R.,O.P. SHARMA, M.D., M.A.M.S. S. MALHOTRA, M.B .B.S., AND SANJAY GUPTA, M.B.B.S., M.D., D.N.B.E. Department of Diagnostic Radiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi 221 005, India.
INTRODUCTION Based on a study of seven cases, a wide spectrum of skeletal abnormalities in cleido-cranial dysostosis is presented, with the emphasis on less commonly reported observations. A few new features are also reported. Changes in the skull consisted of thickening of the squama of the-temporal bone, a rectangular configuration of the calvaria seen on computed tomography and flattening of basiocciput without basilar invagination, hypoplasia of the mastoids and persistence of the fissure at the posterior margin of the foramen magnum. Ribs showed hypoplasia and aplasia. The terminal tufts of the phalanges in one case had totally disappeared. In another case a transverse fissure divided the terminal phalanges of both index fingers. In a further case, bilateral bifid patellae were present. DISCUSSION AND LITERATURE REVIEW Classical features of cleido-cranial dysostosis include absence of all or part of one or both clavicles, brachycephaly and delay in closure of fontanelles and sutures. From the report of Jarvis and Keats (l), who published the largest single series of 40 affected individuals in 8 unrelated families, i t is obvious that the syndrome involves virtually the entire skeleton. A broad spectrum of skeletal abnormalities in this condition is also reported by other workers (2,3).
Key words: Cleido-cranial dysostosis s k e h n l abnormalities Add 'cs for correspondence: Dr 5 . ~Gupta . 2 G.k., Old Medical Enclave Banuras Hindu University Varanasi 22 1 005 Indi:i
238
FIGURE 1 -Lateral SXR showing thickening of squama of temporal bone.
We have come across 7 sporadic cases of cleido-cranial dysostosis, two of which have already been published (3, 4) as single case reports. The purpose of this paper is to review the skeletal abnormalities with the emphasis on less commonly reported observations and also to present some new features. These are a rectangular configuration of the cranial vault seen on CT scan, hypoplasia of ribs, resorption and absence of terminal phalanges, transverse fissuring of the terminal phalanx of the index finger and additional centres of ossification of the patella. Familiar components of cleido-cranial dysostosis are brachycephaly, wide interparietal diameter, hypertelorism, open frontal fontanelle and suture, numerous wormian bones, delayed suture closure, aplasia of clavicles and hereditary transmission (5). Both dominant and recessive inheritance of cleido-cranial dysostosis has been reported and there are occasional sporadic cases (6, 7). All our patients fall into the category of sporadic cases and are explained by genetic muta-
tions. The parents and grandparents of our patients were normal and other siblings in the family were also free from this disorder. Such random occurrences are supported by other studies of patients with normal antecendents and no reports of latency or reappearance of the disorder (6,8). The aetiology of this disease is unknown. The defect is presumably carried in the genes of affected individuals and results in developmental aberration of mesenchymal, beginning in the earliest weeks of embryonic life and producing retarded ossification of membranous and cartilaginous precursors (1). Frontal, parietal and occipital bossing is usually prominent. With the frequent concurrent depression of the sagittal suture, this has been described as the Hot Cross Bun effect (8). Less commonly noted changes are sclerosis or thickening of the squamosal portion of the temporal bone (Figure 1).
Submitted for publication on: 9th July, 1991 Resubmitted for publication on: 11th February, 1992 Accepted for publication on: 17th March, 1992
Australasian Radiology. Vol.36. No. 3. August. 1992
CLEIDO-CRANIAL DYSOSTOSIS Calvarial thickening may also involve the squama of the occipital bone above the level of the external occipital protuberance, giving rise to a squared appearance of the occiput (8). There is often flattening of the basiocciput (2) but without any evidence of basilar invagination (Figure 2). Of particular interest is the occipital and general calvarial contour showing similarities in cleido-cranial dysostosis and osteogenesis imperfecta (9). On computed tomographic examination there is rectangular (Figure 3), instead of the normal oval shaped, configuration of the calvaria, a feature not previously described. CT is not generally required to diagnose or evaluate cases of cleido-cranial dysostosis.
FIGURE 2 -Lateral SXR showing flattening of basiocciput.
RGURJZ 3 - CT Scan showing rectangular contour of calvaria and a defect in the frontal bone. Australasian Radiology, Vol. 36, No. 3 , August, 1992
Some cases of cleido-cranial dysostosis present with mixed deafness due to hypoplasia of the mastoids, poorly pneumatised temporal bones and concentric narrowing of the external auditory canals (10). One of our patients had this type of deafness. The foramen magnum may be deformed and there is often persistence of the fissure at the posterior margin of the foramen magnum (Figure 4).
FIGURE 4 - Towne's view showing a triangular defect in the posterior margin of foramen magnum.
239
S.K. GUPTA et a1 arthrosis may occur forming a false joint between the enlarged ends of clavicles lateral to the mid-portion. The sternal fragment is anterior and superior to the acromial fragment at the pseudarthrosis (1). Pressure on the brachial plexus or subclavian artery by the clavicular fragments has been reported to produce neurologic and vascular symptoms (12). Present at birth, the conical thorax remains throughout life as a distinguishing but not diagnostic mark of cleido-cranial dysostosis (13). The cone shaped thorax appears to be related to the hypoplasia or delayed development of a segment of the posterior part of a vertebral body, the resultant posterior wedging remaining in many adults as a residual deformity. Gross abnormalities in the form of hypoplasia of various degrees involving some of the left sided ribs in one of our cases appears to be a skeletal abnormality not previously described in this condition (Figure 5 ) . Faulty development of centres of embryonic vertebral arches (14) accounts for neural arch defects, hemivertebrae and posterior wedging of the thoracic spine. Spondylolysis and spondylolisthesis may also be seen. Irregular ossification of cervical vertebrae shown by the presence of multiple small osseous nuclei adjacent to the vertebral bodies and a disturbance in ossification of the bodies of dorsal and lumbar vertebrae has also been reported (2). FIGURE 5 - Postero-anterior view of chest showing absence of clavicles on both sides and variable degrees of hypoplasia of left-sided ribs.
Dental abnormalities often cause the patient to seek treatment. Dental dysplasia occurs in almost all patients manifested by delayed or failed eruption of the permanent teeth. Most of the teeth in. cleido-cranial dysostosis fail to erupt throughout adulthood ( 8 ) . Occasionally the symphysis menti remains widened. Mandibular prognathism and maxillary micrognathism have also been reported (6). Clavicular abnormalities give this disorder its characteristic appearance of drooping shoulders, an elongated
240
neck and an ability to approximate the shoulders anteriorly. This feature does not apparently interfere with the capacity to perform physical labour. Davis (1 1 ) reported a patient who because of this anomaly was able to wriggle out of any hold as a college wrestler. Clavicular abnormalities range from a small defect in one clavicle to complete absence of both. The most common deformity is the absence of the central clavicular segment with small bony stumps attached to the sternum and acromion. In approximately 10% of cases the clavicles are entirely absent. Pseud-
A troublesome defect is contraction of the pelvis making childbirth difficult. Dysplasias in the ilial and pubic bones dften narrow the maternal pelvic diameters and alter the birth canal. Hypoplasia of the iliac wings results in loss of normal ilial flaring sometimes producing vertical lateral margins. The pubic symphysis may fail to fuse and remain widened. Widening of the sacro-iliac joints gives a “see-through” appearance in some patients (1). Lateral notching of the capital femoral epiphysis may be present. Unusual ossification may produce broading of the femoral head and widening of femoral neck (3). Other abnormalities seen are coxa valga, coxa vara and irregular mineralisation of the appositional new bone in the acetabula (2, 15). Striking changes occur in the hands. The terminal tufts of the Australasian Radiology. Vol.36. No. 3, August. 1992
CLEIDO - CRANIAL DYSOSTOSIS
FIGURE 6 - X-rays of hands showing variable resorption and absence of the terminal phalanges.
phalanges show characteristic pointing and a variable degree of resorption. In one of our patients, resorption was so extensive that some of the terminal phalanges totally disappeared (Figure 6). We also observed a transverse fissure dividing the terminal phalanges of both index fingers into two parts (Figure 7). These appear to be new osseous observations.
There have been a few case reports of pahtologic fractures and concurrent osteosclerosis in cleido-cranial dysostosis (6, 16, 17), but the distribution of lesions and bone density differed from the pronounced sclerosis typical of marble bone disease. In one of our patients post traumatic fracture of the humerus occurred but there was no evidence of osteosclerosis (Figure 8).
FIGURE 8 - Antero-posterior and lateral X-ray of right humerus showing an oblique fracture of the shaft. Australasian Radiology, Vol. 36, NO.3 , August, 1992
FIGURE 7 - X-ray of hands showing linear transverse fissure dividing the terminal phalanges of index fingers.
We also noted one patient with additional centres of ossification of the patellae (Figure 9) bilaterally. Rarely there are cases with underfunnelization of the tibia1 and fibular metaphyses ( 2 ) . A rare association with cleido-cranial dysostosis is osteogenesis imperfecta and congenital pseudarthrosis of the tibia (18). Congenital femoral pseudarthrosis has also been associated (19). In a patient
FIGURE 9 - Antero-posterior X-ray of knee bipartite patella.
24 1
S.K. GUPTA et a1 with cleido-cranial dvsostosis and , ~. .~~ . . anv ..-~ ~ ~ neurologic symptoms, progressive scoliosis not responding to conservative therapy or progressive scoliosis after skeletal maturation, the presence of syringomyelia shoud be considered. The precise* pathophysiological relationship between cleido-cranial dysostosis and syringomyelia is not understood, but recognition is important for treatment (20). ~
~
~
Our knowledge of the pathogenesis of this disorder and the variety of its skeletal abnormalities is still incomplete. Further collection of case material will undoubtedly show an even broader spectrum.
3.
~
4.
5.
6. 7.
8. 9. 10.
REFERENCES 1.
2.
Jarvis J L and Keats TE. Cleidocranial dysostosis. A review of 40 new cases. Amer Jour Roentgenol 1974; 125: 5-15. Keats TE. Cleido-cranial dysostosis, some atypical findings. Amer Jour Roentgenol 1967; 100: 71-74.
242
11. 12.
Mohan V, Sharma OP, Kumar K. Srivastava TP and Gupta SK. Cleidocranial dysostosis. Ind Jour Orth 1976; 1 0 47-53. Gupta SK, Bhattacharya AK and De DC. Radiological features in cleido-cranial dysostosis. Ind Jour Radiol 1968; 22: 157-160. Marie P and Sainton P. Sur la dysotose Cleido-cranienne hereditaire Rev Neurol 1898; 6: 835-838. Forland M. Cleido-cranial dysostosis. Amer Jour Med 1962; 33: 792-199. Kochs PE and Hammar WB. Cleidocranial dysostosis. Review of literature and report of a case. J Oral Surg 1978; 36: 39-42. Soule AB. Mutational dysostosis. J Bone J Surg 1946; 28: 81-102. Campbell JA. Roentgen aspects of cranial configuration in cleido-cranial dysostosis. Rad CI N Amer 1966; 4: 11-31. Gay IS. A case of dysostosis cleido-cranialis with mixed deafness. J Pharyng and Otol 1958; 72: 915-917. Davis PL. Deafness and cleido-cranial dysostosis. Arch Otalaryng 1954; 59: 602-604. Poynton FJ, Davies HM. Case of cleidocranial dysostosis in which the removal of outer part of imperfect right clavicle relieved severe symptoms from pressure on the brachial plexus. In Proc Roy SOCMed 1914; 8: 25.
13. Miles PW. Cleido-cranial dvsostosis: survev of 6 new cases and 126 'from literaturd. J Kansas M SOC1940; 41 :462-468. 14. Arey LB. Developmental anatomy. Seventh edition. W.B. Saunders Co. Philadelphia 1965; pp 406-410. 15. Saggar RR, Nigam R. Cleido-cranial dysostosis. Ind J Med Assoc 1963; 40: 81-82. 16. Thomsen G and Guttadauro M. Cleidocranial dysostosis associated with osteosclerosis and bone fragility. Acta Radiol 1952; 37: 559-561. 17. Thorns J. Cleido-cranial dvsostosis. Report of two cases with special characteristics. Acta Radiol 1958; 50: 514-556. 18. McGinnis MR and Muller JO. Congenital pseudarthrosis of tibia associated with cleidocranial dysostosis and osteogenesis imperfecta. A case report. Clin Orth 1987; 220: 228-232. 19. Lemperg R. Cleido-cranial dysostosis. Pseudarthrosis femoris congenita. Nord Med 1963; 9: 986-988. 20. Dore DD, Mac-Ewen GD and Boulos MI. Cleido-cranial dysostosis and syringomyelia. Clin Orth 1987; 214: 229-234.
Australasian Radiology, Vol. 36. No. 3, August. 1992
