Laurin-Sandrow syndrome (LSS) is an extremely rare syndrome of mirror hand and leg with less than 20 cases reported in literature. The syndrome has been attributed to a mutation in the MIPOL-1 (mirror-image polydactyly) gene located on locus 14q13.3-q21 coding for CCDC193 (coiled-coli domain containing 193) protein. It is characterised by limb, facial and central nervous system anomalies with the most constant being fibular dimelia with fibular ray duplication, polydactyly with secondary deformities of fixed equinus, knee joint instability and flexion deformity. It is associated less frequently with ulnar dimelia, thumb aplasia/hypoplasia, ulnar ray duplication, symbrachypolydactyly, \'rosette\' hands, facial dysmorphism like hypertelorism, broad columella and flat nose, CNS anomalies like aplasia/hypoplasia of corpus callosum, hydrocephalus and muscular dystonia. We report a 2-year-old male child with LSS and perform a literature review to expound on this rare syndrome. Level of Evidence: Level V (Therapeutic).

OBJECTIVE: Congenital palmar nail (distal dorsal dimelia [dDD]) of the hand is a rare malformation most commonly affecting the little finger. The purpose of this report was to review the features and associations of this rare disorder and discuss the suspected underlying etiology in light of our current understanding of developmental biology.
METHODS: In this retrospective cohort study from 3 practices, we describe our collective experience and review the reported literature on this disorder both as an isolated condition and in conjunction with other anomalies.
RESULTS: We examined 15 fingers with dDD, 5 of which involved little fingers. We also found dDD in 6 cases with radial polydactyly (preaxial polydactyl type II [PPD2]) and in 1 case of cleft hand involving digits adjacent to the clefted web space (the index and middle fingers). Cases of little finger dDD were also associated with prominent clefting of the adjacent web space in 4 of 5 cases. All cases had stiffness of the interphalangeal joints and loss of palmar creases consistent with dorsalization of the palmar aspect of the digit. When combined with 63 fingers reported in the literature with dDD, 3 patterns were evident. The most common form occurred in little fingers (n = 50; 64%; dDDu). The next most common form was reported in association with cleft hands (n = 16; 21%; dDDc). Radial digits in association with either radial polydactyly (PPD2) or radial longitudinal deficiency were also susceptible to dDD (n = 12; 15%; dDDr).
CONCLUSIONS: Congenital dDD is a disturbance of terminal dorsal-ventral digit patterning. The distribution of this condition with little fingers, clefting, and altered radial digit formation (PPD2 or radial longitudinal deficiency), as well as recent genetic and animal studies, suggests that dDD and altered dorsal-ventral patterning are linked to abnormal apical ectodermal ridge boundary formation.
METHODS: Diagnostic IV.

OBJECTIVE: To determine the sensitivity, specificity, and predictive values of prenatal ultrasound detection of fetal upper extremity anomalies at a single tertiary care center in a large patient cohort. Our secondary purpose was to assess factors affecting prenatal detection including the presence of associated anomalies.
METHODS: We performed a retrospective review of prenatal ultrasound and postnatal clinical records from each pregnancy evaluated with a prenatal ultrasound at the Washington University Department of Obstetrics and Gynecology over a 20-year period. We searched for upper extremity anomaly diagnosis codes pre- and postnatally and correlated with clinical postnatal follow-up to determine prevalence, sensitivity, specificity, predictive values, and associated conditions.
RESULTS: A total of 100,856 pregnancies were evaluated by prenatal ultrasound, which included 843 fetuses diagnosed with a musculoskeletal anomaly (prevalence, 1 of 120) and 642 with an upper extremity anomaly (prevalence, 1 of 157). The postnatally confirmed sensitivity for prenatal ultrasound detection of an upper extremity anomaly was 42%. Sensitivity was lower in cases isolated to the upper extremity (25% vs 55%). Sensitivity was highest for conditions affecting the entire upper extremity (70%-100%) and lowest for those affecting the digits alone (4%-19%). Fetuses with limb reduction defects, radial longitudinal deficiency, phocomelia, arthrogryposis, abnormal hand positioning, and cleft hand had a higher likelihood of having an associated anomaly.
CONCLUSIONS: At our tertiary referral center, there was a notable prevalence of upper extremity anomalies; however, the overall sensitivity for detecting them with prenatal ultrasound was low. This was disappointing given the value of prenatal identification of anomalies for parental counseling. Prenatal diagnosis of anomalies affecting the entire upper limb was more reliable than diagnosis of more distal anomalies.
METHODS: Diagnostic III.