Congenital constriction band syndrome with limb defects.

BACKGROUND: The purpose of this study was to clarify the spectrum of congenital constriction band syndrome (CBS) and associated anomalies and mortality in Finland. METHODS: Register-based data were analyzed for children with congenital constriction bands in upper and lower extremities as a part of an ongoing study on 419 upper limb defects and 171 lower limb defects occurring among 753,342 births in Finland during 1993 to 2005. RESULTS: A total of 71 cases with limb CBS were identified during the 13-year study period. The birth prevalence was 0.9 per 10 000 births (1:10 600). Infant mortality was 4.6% (3/65) and perinatal mortality 12.7% (9/71). In 35 cases (49%) only upper limbs were affected and in 13 cases (18%) there were constriction defects only in lower limbs. In 23 cases (32%) both upper and lower limbs were involved. None of the cases associated with a known syndrome. However, in 21 cases (30%) the child had other anomalies associated with constriction rings: pes equinovarus in 8/21, cleft palate in 5/21, congenital heart defect in 6/21, and other anomalies in 14/21. Eighteen (25%) had low birth weight, 22 (31%) were born preterm, and 8 children (11%) were small for gestational age. Children with associated anomalies showed higher mortality, shorter duration of gestation, and lower birth weight. CONCLUSIONS: CBS is rare and comprises approximately 12% of all congenital upper limb defects and 14% of lower limb defects. Other skeletal and nonskeletal anomalies are present in 30% of the affected children, suggesting a possible genetic etiology. More detailed characterization of the children with associated anomalies may shed light to the pathogenetic mechanisms of this syndrome. LEVEL OF EVIDENCE: Population-based register study/II.

High risk for major nonlimb anomalies associated with lower-limb deficiency: a population-based study.

BACKGROUND: The aims of this study were to determine the prevalence of congenital lower-limb reduction defects and associated mortality, to evaluate lower-limb deficiencies by type of reduction, and to identify patterns of associated anomalies. METHODS: We conducted a population-based study with use of data from the Finnish Register of Congenital Malformations and Care Register for Health Care. All cases of lower-limb deficiency among live births, stillbirths, spontaneous abortions, and terminations of pregnancy due to fetal anomalies from 1993 to 2008 were included. We analyzed medical records and classified lower-limb reduction defects. Associated major anomalies were recorded, and perinatal mortality and infant mortality were calculated. RESULTS: Two hundred and sixty-six cases with lower-limb deficiency were identified, with a total prevalence of 2.8 per 10,000 births, a birth prevalence of 2.2 per 10,000 births, and a live-birth prevalence of 2.1 per 10,000 live births. Terminal transverse limb reductions accounted for 44.7% of the cases; longitudinal reductions, 22.9%; intercalary reductions, 7.9%; multiple reductions, 8.3%; and split-foot malformations, 4.5%. In addition to lower-limb deficiency, 47.7% of the cases had other major anomalies; anomalies of internal organs were noted in 26.3% of the cases, anomalies of the axial skeleton in 13.5% of cases, and central nervous system anomalies in 12.8%. Upper-limb reductions were observed in 32.0% of the cases. The relative risk (RR) for associated major anomalies was 12.54 (95% confidence interval [CI], 11.06 to 14.23) compared with the general figures for major congenital anomalies in Finland. The RR for associated anomalies was higher (1.75; 95% CI, 1.20 to 2.53) for longitudinal preaxial lower-limb deficiencies than for the other types of lower-limb reductions. Perinatal mortality was seventy-eight per 1000 births. All infant deaths were associated with chromosomal abnormalities, other known syndromes, or additional congenital malformations. CONCLUSIONS: Nearly half of the cases with lower-limb deficiencies were found to have other major anomalies. In cases of preaxial lower-limb deficiencies, the risk for associated major anomalies was highest.

Characteristics and associated anomalies in radial ray deficiencies in Finland--a population-based study.

Upper-limb defects with deficiencies of the radial ray have varying etiologies, with a low proportion of true Mendelian disorders. We carried out a population-based study to elucidate the birth prevalence and clinical spectrum of radial ray deficiencies in Finland. We identified all births with radial ray deficiency reported to the Finnish Register of Congenital Malformations in 1993-2005. Altogether 138 cases were identified (123 live births), with a birth prevalence of 1.83 per 10,000 births and a live birth prevalence of 1.64 per 10,000 live births. The proportion of infant deaths was as high as 35%. The majority of the cases were associated with known syndromes or multiple anomalies; only 13% were true isolated radial ray deficiencies. The most common syndrome was trisomy 18, and the most common in multiple anomalies was VACTERL association. In 8.7% of cases an association between radial ray deficiency and heart anomaly was observed. The high proportion of cases with associated major anomalies indicates that radial ray deficiency can be regarded isolated only after thorough assessment of the various organ systems in an affected infant.

Congenital upper limb deficiencies and associated malformations in Finland: a population-based study.

PURPOSE: To calculate the national incidence of upper limb deficiencies and associated infant mortality in children in Finland using the International Federation of Societies for Surgery of the Hand (IFSSH) classification. Radial ray deficiency, ulnar ray deficiency, central ray deficiency, transverse arrest, phocomelia, undergrowth, and constriction band syndrome with skeletal defects were evaluated. METHODS: We reviewed upper limb deficiencies among all 753,342 births in Finland during 1993 to 2005 reported to the Finnish Register of Congenital Malformations. Classification of these upper limb deficiencies was done according to a modified IFSSH system. We calculated incidence, gender and side distributions, frequency of associated anomalies, and infant mortality rates in different subtypes of the deficiencies. Familial occurrence of congenital upper limb defects was recorded. RESULTS: A total of 419 cases (234 male, 185 female) of upper limb deficiencies were identified. The national incidence of upper limb deficiencies was 5.56 per 10,000 births and 5.25 per 10,000 live births. The most common upper limb abnormality was radial ray deficiency (138), followed by subgroups of undergrowth (91), upper limb defects due to constriction band syndrome (51), central ray deficiency (41), and ulnar ray deficiency (33). Perinatal mortality was 14%. Infant mortality among children with upper limb deficiencies was 137 per 1,000 live births, compared with an overall infant mortality of 3.7 per 1,000 live births in Finland. Additional birth defects were found in 60% of these children. Prevalence of upper limb defects in relatives of the census population was 2% (11 of 419). CONCLUSIONS: The national incidence of upper limb deficiencies is 5.25 per 10,000 live births. Congenital upper limb deficiencies are associated with additional birth defects in two thirds of cases. These children, especially children with radial ray deficiency, have a high perinatal mortality rate. When divided into subgroups using IFSSH classification, differences emerge in both associated anomalies and mortality.