BONE AND JOINT CONGENITAL DISORDERS WRIST DISORDERS
Congenital anomalies affect 1% to 2% of newborns • approximately 10% of those children have upper-extremity abnormalities
BONE AND JOINT CONGENITAL DISORDERS Osteochondral dysplasias Metabolic disorders Syndroms
Osteochondral dysplasias Achondroplasia Hypochondroplasia Diastrophic dysplasia Kniest dysplasia Spondyloepiphyseal dysplasia Metaphyseal chondrodysplasia Dyschondrosteosis
achondroplasia AD pre. =1.3/100000 80% random new mutation (paternal age) Collagen type II chromosome 12 Enchondral ossification Rhizomelic shortness
achondroplasia Limitation in elbow extension Genu varum Ankle valgus Waddling gait Hip flexion contracture Motor retardation Kyphosis in spine
achondroplasia Mortality rate is increased because of: Sudden death CNS CV
Metabolic disorders Mineral phase Rickets Organic phase Oi Osteopetrosis Conective tissue syndroms Endocrinopathies Hypothyroidism Gonadal abnormality Fibrous dysplasia
Osteogenesis imperfecta Collagen I Fragility of bone 21.8/100000 Short stature , scoliosis Defective dentinogenesis Middle ear deafness Laxity of lig. Blue sclerae & tympanic membrane Prenatal diagnosis by US except In mild forms( I,IV)
Increase in woven bone does not mature to lamellar bone Osteocyte are increased Trabeculae are thin and poorly arranged Haversian canal does not developed Bone mineral density is decreased on DEXA
Osteogenesis imperfecta OI congenita OI tarda
SHORT STATURE BOWING OF LIMBS SCOLIOSIS BLUE SCLERA I,II DENTINOGENESIS IMPERFECTA TREFOIL SHAPED FACE
Coxavara Protrusioacetabuli Wormian bones Biconcave vertebra Long bones are thin and osteopenic Concertina appearance in femur Widening of metaphysis , popcorn epiphysis
Syndroms Neurofibromatosis Arthrogryposis Down syndrome Turner syndrome Noonan syndrome
Neurofibromatosis (von Recklinghausen's disease) is the most prevalent skeletal dysplasia transmitted by a single gene. It is inherited in an autosomal dominant pattern with variable expression, although the disease is believed to occur due to a new mutation in 50% of the affected individuals. The estimated prevalence is 1 per 1000 live births.
Neurofibromatosis type I (NF-I) is the more common form and is characterized by peripheral neurofibromas, skeletal involvement, and “café au lait spots.” The genetic locus for NF-I has been localized to chromosome 17q11.2, an area that encodes for the protein neurofibromin . This protein is present in several organ systems and is believed to be a tumor suppressor . Neurofibromatosis type II (NF-II) manifests as central neurofibromas with bilateral acoustic neuromas and usually presents in the third or fourth decade of life . The gene for NF-II has been localized to chromosome 22 and encodes for the protein schwannomin .
Plexiform neurofibromas are large nerve tumors that are locally invasive, feel like a “bag of worms,” and have the potential for malignant transformation. • Skeletal lesions: Scoliosis is most common • Hypertrophy or hemiatrophy due to neurofibromatosis can be seen • Congenital pseudarthrosis of the tibia and forearm may be present. • Protrusio acetabuli
CONGENITAL ELEVATION OF THE SCAPULA (SPRENGEL'S DEFORMITY) • Results from a failure of the normal caudal migration of the scapula during the fetal period of development . • Scapula with this malformation is usually hypoplastic with decreased vertical length and increased horizontal width-to-height ratio , which is 2 to 10 cm more cephalad than normal
ROTATION The inferior pole is rotated medially with the glenoid displaced inferiorly. • The periscapular muscles may be hypoplastic or absent, causing scapular winging . • Right = left • bilateral involvement = 10% to 30%
Assossiated anomalies Scoliosis Klippel-feil syndrom Rib cage CDH Hand Foot Renal
Longitudinal failure of formation Radial club hand Ulnar club hand
Radius deficiency 1:30,000 nearly always associated with thumb and carpal deficiencies and frequently associated with other upper extremity anomalies, anomalies of other organ systems, and syndromes VACTERL association (not inheritable; it may be accompanied by Vertebral, Anal, Cardiac, Tracheo-Esophageal, Renal or Radial, and Lung anomalies) Holt-Oram syndrome (autosomal dominant inheritance of cardiac septal defects associated with upper limb anomalies) TAR syndrome (autosomal dominant or recessive inheritance of completely absent radius with a near-normal thumb and thrombocytopenia) .
Radius deficiency is usually bilateral, although the two sides are frequently asymmetric; when the condition is unilateral, it is more common on the right . The radial wrist extensors and extrinsic thumb motors are usually absent or aberrant. The radial nerve is usually absent below the elbow, and the median nerve is always present and often the most prominent structure on the radial side of the wrist. The radial artery is usually absent.