Scapular Abnormalities

In this section some of the commonest scapular abnormalities are reviewed, with special reference to those useful in the radiographic recognition of malformation syndromes and skeletal dysplasias. A number of additional congenital anomalies of the scapula, often occurring as isolated defects of minor diagnostic value, are not discussed in detail. These anomalies include elongated acromion, absent acromion, double acromion and coracoid, clasp-like superior border of the scapula, coracoclavicular joint, convex glenoid, hypoplasia of the inferior border of the glenoid, dentate glenoid, infrascapular bone, and radiolucent notches (Samilson 1980; Mc-Clure and Raney 1975; Kim and Min 1994; Cigtay and Mascatello 1979; Edelson 1996). The os acromiale, an unfused acromial ossification center that persists as an individual bone articulating with the remainder of the acromion, should not be misinterpreted as a fracture fragment. The 'hook-shaped' scapula, a sickle-like, outward bending of the inferior angle of the scapula, has been observed in a patient with features of pseudo-pseudohypoparathyroidism, hearing loss, arched palate, and restricted motion at the elbow (Silverman 1993) and in a patient with Robin sequence (Bezirdjian and Szucs 1989). Scapular duplication, a rare congenital anomaly with only a very few documented cases, consists of a craniomedially placed scapula that articulates with the clavicle and a caudolaterally located scapula that articulates with the humeral head (Fig. 2.43). The contralateral scapula is normal. Occasional associated skeletal anomalies, including upper limb defects (especially proximal deficiency of the humerus) and scoliosis, are inconstant features (Martini and Neusel 1987; Stacy and Yousefzadeh 2000).

The most important and common anomaly of the scapula is congenital uni- or bilateral failure of descent, or Sprengel deformity. The scapula remains in an abnormally high position, sometimes anchored to the cervical spine by a bony (omovertebral bone), cartilaginous, or fibrous bridge (Baulot et al. 1998). Occasionally, an accessory ossicle is found at the insertion of the levator scapulae muscle (Gallien 1985). The point of tethering of the omovertebral connection is likely to determine the shape, rotation, medial migration, and superior displacement of the scapula (Leibovic et al. 1990). The scapula is smaller than normal, with a decrease in the height-to-width ratio. The degree of scapular rotation is inversely correlated to the superior displacement (Cho et al. 2000). Sprengel deformity can occur as an isolated anomaly

Scapula Anomaly

Fig. 2.43. Scapular duplication in a 2-month-old child. Note complete duplication of the left scapula. The scapula located higher is larger and shows a dysplastic glenoid fossa, but looks otherwise normal and articulates normally with the left clavicle. The inferior scapula is smaller and shows a normally developed acromion.A vestigial, severely shortened humerus not articulating with the shoulder girdle, and fused to the radius at a right angle can also be seen. The bones in the hand (not shown) were not affected. (From Stacy 2000)

Fig. 2.43. Scapular duplication in a 2-month-old child. Note complete duplication of the left scapula. The scapula located higher is larger and shows a dysplastic glenoid fossa, but looks otherwise normal and articulates normally with the left clavicle. The inferior scapula is smaller and shows a normally developed acromion.A vestigial, severely shortened humerus not articulating with the shoulder girdle, and fused to the radius at a right angle can also be seen. The bones in the hand (not shown) were not affected. (From Stacy 2000)

Dentate Anomaly Scapula
Fig. 2.44. Isolated Sprengel anomaly in a young man with no other detectable skeletal defects. The scapula is well formed but is markedly hypoplastic and located in an abnormally high position. No omovertebral bone can be seen

(Fig. 2.44), in association with other congenital defects, such as congenital scoliosis and renal anomalies, or in the context of a fully delineated disorder, such as Klippel-Feil syndrome (OMIM 148900) (van Kerckhoven and Fabry 1989; Greenspan et al. 1991), nevoid basal cell carcinoma syndrome (Gorlin syndrome, OMIM 109400) (Kimonis et al. 1997), and VATER association (OMIM 192350) Fernbach and Glass 1988). Frydman et al. (1993) described a male infant born to consanguineous Jewish parents originating from Bombay (India), who had anal atresia, omphalocele, prune belly, urethral obstruction, dilated ureters, dysplastic kidneys, congenital heart defects, and thoracolumbar scoliosis. The mother and all three sisters had cervical ribs. One sister had chronic immune thrombocytopenia, Sprengel deformity, and clubfoot. Another sister had chronic immune thrombocytopenia and preaxial polydactyly. It has been suggested that these abnormalities were different manifestations of the same syndrome with variable expressivity in males and females (or in homo- and heterozygotes) (Frydman et al. 1993). This disorder is recorded as 'cervical ribs, Sprengel anomaly, anal atresia, and urethral obstruction' (OMIM 601389) (McKusick).

Hypoplasia of the scapula, with or without hypoplasia of the glenoid fossa, is a major radiographic sign used in the diagnosis of several bone dysplasias, including cleidocranial dysplasia (OMIM 119600), campomelic dysplasia (OMIM 114290, 211990) (Fig. 2.45), achondrogenesis (OMIM 200600, 200610, 200700), Antley-Bixler syndrome (OMIM 207410) (Fig. 2.46), de la Chapelle syndrome (OMIM 256050), hypophosphatasia (OMIM 241500), Klippel-Feil syndrome (OMIM 148900), nail-patella syndrome (OMIM 161200), pelvis-shoulder dysplasia (OMIM 169550), short rib-polydactyly syndromes (OMIM 263510,263520,263530) (Fig. 2.47),and thanatophoric dysplasia (OMIM 187600, 187601) and variants (OMIM 151210) (Fig. 2.48) (Mortier et al. 1997). It also occurs in association with Sprengel deformity and glenoid dysplasia. Pelvis-shoulder dysplasia (scapuloiliac dysostosis, OMIM 169550) includes marked hypoplasia/aplasia of the scapular and iliac wings, hypoplastic acetabula with bilateral hip dislocation, hypoplasia of the clavicles, rib anomalies, spina bifida, and - in some cases only - anomalies of the eye (ectopic pupil, retinal coloboma, coloboma of the eyelids, corneal opacification, hypertelorism), low-set ears, and micrognathia (Kosenow et al. 1970). Evidence for autosomal dominant inheritance has been provided (Amor et al. 2000). Pelviscapular dys-plasia (OMIM 260660), a disorder phenotypically similar to pelvis-shoulder dysplasia, is inherited as an autosomal recessive trait (Cousin et al. 1982; Elliott et al. 2000). An association of Robin-type cleft palate, rib'dysplasia,' scapular hypoplasia,and pectus excavatum (OMIM 602196) has been reported in five generations of a family, with instances of male-tomale transmission suggesting autosomal dominant transmission of a trait with variable expressivity (Stalker and Zori 1997).

Campomelic

Fig. 2.45. Campomelic dysplasia in a female newborn who died 2 h after birth. The scapulae are severely hypoplastic, each with unossified body and caudal portion. Some of the pedicles in the thoracic spine are also unossified. (From Mortier et al. 1997)

Fig. 2.47. Short rib-polydactyly syndrome type II (Majewski) in a stillborn fetus. Note severe hypoplasia of the scapulae. The medial border and glenoid fossa are smooth and rounded, similar in appearance to the metaphyseal ends of the long tubular bones in this condition. (From Mortier et al. 1997)

Fig. 2.45. Campomelic dysplasia in a female newborn who died 2 h after birth. The scapulae are severely hypoplastic, each with unossified body and caudal portion. Some of the pedicles in the thoracic spine are also unossified. (From Mortier et al. 1997)

The terms glenoid dysplasia, glenoid hypoplasia, and shallow glenoid, are used interchangeably to describe a developmental anomaly of the scapula characterized by incomplete ossification of the lower two-thirds of the bony glenoid and adjacent part of the scapular neck resulting in underdeveloped inferior glenoid promontory. This subject has been reviewed by Currarino et al. (1997). For the purposes of the following discussion, we will use Currarino's system of classification into five types: (1) Isolated primary glenoid dysplasia. This lesion, which may occur on a familial basis (Weishaupt et al. 2000; Stanciu and Morin 1994), is most often bilateral and symmetrical and can either be totally asymptomatic, especially in children (Kozlowski et al. 1985; Ko-

zlowski and Scougall 1987), or manifest with a constellation of symptoms ranging from joint stiffness and pain to chronic joint instability (Grout and Resnick 1996; Lintner et al. 1992) (Fig. 2.49). Premature development of osteoarthritis is a potential complication. (2) Glenoid dysplasia associated with multiple anomalies or ill-defined syndromes. Congenital glenoid dysplasia has been reported in several members in the same family in association with a stiff joint, scoliosis, ulnar shortening, brachymeso-phalangy, and clinodactyly (Fuhrmann et al. 1968); and in a 5-year-old child as part of a constellation of anomalies, including low-set ears, cleft lip, high palate, nail hypoplasia, hydrocele, and pulmonary stenosis (Kozlowski et al. 1985). Of the four addition-

Antley Bixler
Fig. 2.46. Antley-Bixler syndrome: postmortem radiograph of an 11-week-old female infant. Note marked hypoplasia of the scapulae, with a characteristic inverted U configuration. The degree of hypoplasia is less severe than in campomelic dysplasia (see Fig. 2.45). (From Mortier et al. 1997)
Scapula Xray And Noonan Syndrome

Fig. 2.48. PLSD (thanatophoric variant), Luton type in a 4-day-old male infant. In addition to being hypoplastic, the scapulae show two characteristic spikes at the inferior scapular angle. This feature is specific for the Luton type of PLSD and is not seen either in the San Diego type or the Torrance type. (From Mortier et al. 1997)

Fig. 2.51. Hurler syndrome in a 6-month-old boy. The glenoid is dysplastic on both sides. (From Currarino et al. 1997)

Fig. 2.48. PLSD (thanatophoric variant), Luton type in a 4-day-old male infant. In addition to being hypoplastic, the scapulae show two characteristic spikes at the inferior scapular angle. This feature is specific for the Luton type of PLSD and is not seen either in the San Diego type or the Torrance type. (From Mortier et al. 1997)

al cases reported by Currarino, a newborn male had esophageal atresia, poorly ossified sternum, lumbar hemivertebrae,hip dislocation, absent fibulae or tibiae, and flat feet; a 7-month-old girl had dysmorphic facies, cleft lip and palate, hydrocephalus, cardiovascular anomalies,hypothyroidism, and poorly ossified sternum; a 1-year-old girl had multiple contractures and cleft palate; and a 15-year-old boy had severe pectus excavatum, thoracic scoliosis, and restriction of right shoulder movements (Currarino et al. 1997). (3) Glenoid dysplasia associated with distinct syn dromes, including Grant syndrome (OMIM 138930), ophthalmomandibular dysplasia (OMIM 164900),TAR syndrome (OMIM 274000), Apert syndrome (OMIM 101200) (Fig. 2.50), Holt-Oram syndrome (OMIM 142900), multiple synostoses syndrome (OMIM 186500), trisomy 8 syndrome, nail-patella syndrome (OMIM 161200), Noonan syndrome (OMIM 163950), and diabetic fetopathy. Grant syndrome (OMIM 138930) is a very rare disorder related to osteogenesis imperfecta, characterized by bowed bones, blue scle-rae, mandibular hypoplasia, short stature, wormian bones, osteopenia, and glenoid dysplasia with shoulder dislocation. Unlike the picture in osteogenesis imperfecta, there is no tendency to fractures or dentinogenesis imperfecta (Maclean et al. 1986). (4) Glenoid dysplasia associated with metabolic disorders includes mucopolysaccharidosis I-H (OMIM 252800) (Fig. 2.51), II (OMIM 309900), IV (oMIM 253000), and VI (OMIM 253200), mucolipidosis II (OMIM 252500), III (OMIM 252600), fucosidosis (OMIM 230000), and mannosidosis (OMIM 248500). (5) Glenoid dysplasia associated with skeletal dysplasias includes diastrophic dysplasia (OMIM 222600), pseudoachondroplasia (OMIM 177170) (Fig. 2.52), multiple epiphyseal dysplasia (OMIM 132400) (Fig. 2.53), metaphyseal chondrodysplasia (Schmid type, OMIM 156500), and spondyloepimeta-

What Glenoid Dysplasia
Fig. 2.49. Isolated glenoid dysplasia in a 1-month-old boy. There is severe bilateral glenoid dysplasia in this child, in whom a chest X-ray examination was performed because pneumonia seemed possible. (From Currarino et al. 1997)
Chest Xray Child Scapular

Fig. 2.52. Pseudoachondroplasia in a 4-year-old boy. The glenoid is shallow with indistinct margins. The metaphysis of the proximal humerus is markedly widened and dysplastic, and epiphyseal ossification is defective

Glenoid Dysplasia
Fig. 2.54. Bilateral glenoid dysplasia in an 11-month-old boy with a pronounced neuromuscular disorder attributed to severe hypoxia at birth. (From Currarino et al. 1997)

Fig. 2.52. Pseudoachondroplasia in a 4-year-old boy. The glenoid is shallow with indistinct margins. The metaphysis of the proximal humerus is markedly widened and dysplastic, and epiphyseal ossification is defective

Dysplastic Glenoid
Fig. 2.53. Multiple epiphyseal dysplasia in a 4-year-old boy. The glenoid fossae are severely dysplastic. (From Currarino et al. 1997)

physeal dysplasia (Strudwick type, OMIM 184250) (Samilson 1980; Currarino et al. 1997; Kozlowski et al. 1985). Unilateral glenoid hypoplasia with findings similar to those of the congenital form occurs on a secondary basis in patients with Erb's palsy (Pollock and Reed 1989) and neuromuscular disorders (Pet-tersson 1981) (Fig. 2.54). Given the large number of conditions with which it can be associated, glenoid dysplasia is a nonspecific radiologic sign with limited diagnostic value.

The scapula is involved in generalized disorders of the skeleton. For example, focal or diffuse sclerosis of the scapula is seen in sclerosing bone dysplasias, such as osteopoikilosis (OMIM 166700), melorheos-tosis (OMIM 155950), osteopathia striata, osteopetrosis (OMIM 166600), Camurati-Engelmann disease (OMIM 131300),van Buchem syndrome (OMIM 239100), and Pyle disease (OMIM 265900).

A number of acquired conditions can affect the scapula, causing either enlargement or destruction (focal or massive). Examples of conditions with primary or secondary involvement of the scapula include histiocytosis X, chronic osteomyelitis, Ewing sarcoma, metastases, leukemia, lymphoma, malignant fibrous histiocytoma, hemangioma, lymphan-gioma, and aneurysmal bone cysts.

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Pregnancy Diet Plan

Pregnancy Diet Plan

The first trimester is very important for the mother and the baby. For most women it is common to find out about their pregnancy after they have missed their menstrual cycle. Since, not all women note their menstrual cycle and dates of intercourse, it may cause slight confusion about the exact date of conception. That is why most women find out that they are pregnant only after one month of pregnancy.

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  • hildigard baggins
    What is noonan syndrome, pictures of children with this?
    8 years ago
  • stephanie
    What conditions are associated with an etopic scapula?
    6 years ago

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