ZC4H2 is an X-linked gene that has emerged as critical for neural development, synaptic functioning, and gene regulation. We present an 11-month-old male who was evaluated for bilateral congenital vertical talus identified in the newborn period. Exome sequencing identified a hemizygous, missense variant in ZC4H2, NM_018684.4:c.196C>T p.(Leu66Phe), that affects the same amino acid residue as a previously reported, pathogenic ZC4H2 variant, c.197T>A p.(Leu66His). The variant was inherited from his mother, who had camptodactyly of the fifth fingers, and was also present in the maternal uncle who carried a diagnosis of cerebral palsy. The pathogenic missense variant in this family is located in the coiled-coil domain of the ZC4H2 protein. Although data remain scarce, missense variants in this domain may be associated with a milder, ZC4H2-associated rare disorder (ZARD) phenotype.

We investigated the radioclinical outcomes of naviculectomy and limited/tailored soft-tissue releases in a short series of ambulatory children with complex/intractable congenital vertical talus subsets namely neglected, multiple operated, and recurrent patients. We postulated that this technique will yield satisfactory radioclinical outcomes and minimal complications because it avoids extensive surgical release/trauma that is otherwise classically recommended for complex congenital vertical talus. The cohort consisted of 5-4 boys and 1 girl-complex congenital vertical talus children with neglected, multiple operated, and/or recurrent subsets. Patients were included if manipulative casting techniques were deemed unlikely to produce a plantigrade foot. Patients underwent naviculectomy with variable on-demand limited soft-tissue releases. Two patients had bilateral affection and 2 had a nonidiopathic cause. The mean age was 5.2 years (4-6.25) and mean follow-up was 2.3 years (1-3). We reported satisfactory outcomes as per foot posture, function, overall parent satisfaction including pain and radiography per lateral views of talar-axis-first metatarsal base angle on the short/intermediate term. Whereas manipulative casting is unlikely to yield lasting outcomes in ambulatory children with complex subsets of congenital vertical talus, extensive surgical soft-tissue releases have unfavorable long-term complications. As a substitute, naviculectomy as a form of resection arthroplasty created a practical and affordable third way between manipulative casting with or without minimally invasive surgery and the extensive surgical soft-tissue releases on the short-to-intermediate term.Level of Evidence:Level IV case series.

Congenital vertical talus (CVT) and congenital oblique talus (COT) are rocker-bottom foot deformities that have similar names and no objective definitions. This has led to confusion for practitioners, as well as scientific challenges for researchers. Our goal was to provide objective radiographic criteria to define and differentiate CVT and COT. We evaluated 62 pairs of maximum dorsiflexion and plantar flexion lateral radiographs of infant feet that had been clinically diagnosed with CVT. The dorsiflexion tibiotalar angle, the plantar flexion talus-first metatarsal angle, and the plantar flexion foot center of rotation of angulation (foot-CORA) were measured using transparent overlay tools. Freehand measurements were made on a subset of 10 pairs of radiographs to confirm clinical applicability. Nine contralateral pairs of radiographs of normal feet were measured for comparison. Specific values for the radiographic measurements were identified that, together, reliably differentiated the shapes of rocker-bottom feet with CVT, COT, and flexible flatfoot with a short tendo-Achilles (FFF-STA), as well as the shape of the normal foot. More severe and rigid rocker-bottom foot deformities were diagnosed with CVT. Less severe and more flexible deformities were diagnosed with COT. CVT, COT, FFF-STA, and normal feet can be reliably differentiated using 2 angular measurements and 1 bone position measurement on dorsiflexion and plantar flexion lateral radiographs. Our data indicated that the differentiation of CVT and COT is based primarily on the rigidity of the navicular dislocation rather than the verticality of the talus. The data further supported the proposition that COT is a foot deformity along a spectrum of valgus/eversion deformities of the hindfoot that requires early treatment. Application of these diagnostic criteria should lead to clinical studies that identify a specific treatment, treatment outcome, and prognosis for each deformity. Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Nicolaides-Baraitser syndrome (NCBRS) is a rare autosomal dominant genetic condition that is characterized by severe intellectual disability, dysmorphic facial features, short stature, sparse hair, and early onset seizures. This diagnosis is established by suggestive clinical findings and the identification of a heterozygous SMARCA2 pathogenic variant by molecular genetic testing. There are not, however, consensus clinical diagnostic criteria for this condition as there are so few documented cases. Here, we present a case of prenatally diagnosed caudal regression with sacral agenesis and congenital vertical talus (rocker bottom feet) that was ultimately found to have a de novo SMARCA2 pathogenic variant. The patient had an amniocentesis with normal karyotype and microarray followed by failed direct rapid whole exome sequencing (WES) due to maternal cell contamination. She elected for termination of the pregnancy based on the clinical prognosis of the ultrasound findings; WES revealed a pathogenic variant after her termination. We believe this is the first case of these findings associated with NCBRS. If any future cases of either finding are found in association with a SMARCA2 genetic variant, caudal regression and rocker bottom feet should be included in the spectrum of physical traits associated with this pathogenic variant.

Congenital Vertical Talus (CVT) is a rare form of rigid flatfoot commonly seen in patients with underlying neurologic syndromes. This study aims to evaluate the long-term effectiveness of the minimally invasive method for correcting CVT deformity in a large cohort of syndromic patients. A single author recorded preoperative, 2-week postoperative, 1-year postoperative, and most recent radiographic measurements and complications for 25 patients treated with the minimally invasive method from 2006 to 2021. Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaires were administered for 12 patients after January 1, 2015, when the institution began collecting PROMIS in all orthopaedic patients. Average follow-up was 55 months (13-111); 18 patients had minimum 24-month follow-up. Forty feet in 25 patients were analyzed. The average preoperative lateral talar axis-first metatarsal base angle (TAMBA) was 68.7 ± 21.3 vs 12.1 ± 8.9 after initial surgical intervention (P < .0001). There was a statistically significant increase in the lateral TAMBA between the initial postoperative and final follow-up visits (13.0 vs 21.6, P = .02). Radiographic recurrence of talonavicular deformity was noted in 12 feet (30.9%); 7 (15.55%) required corrective surgery. Larger preoperative lateral TAMBA was predictive of recurrence. Notably, patients with arthrogryposis experienced higher radiographic recurrence than other syndromic patients (45.0% vs 14.3%, P = .0384). PROMIS scores were within population norms. The study suggests that less than one-third of syndromic CVT patients experienced a radiographic recurrence of talonavicular deformity, with 15% requiring further surgical intervention at an average of 55 months following the initial procedure. A higher incidence of radiographic recurrence occurred in patients with distal arthrogryposis. These findings, along with the satisfactory patient-reported outcomes, suggest that the minimally invasive technique is an effective treatment method for syndromic CVT, underscoring the necessity for clinicians to provide detailed prognoses and consider more intensive follow-up for those at higher risk.