Bilateral Multiple Tarsal Coalitions (Talonavicular and Talocalcaneal Coalitions) with Recurrent Ankle Sprain in an Adolescent

Tarsal coalition is defined as an abnormal bony, cartilaginous, or fibrous union of two or more tarsal bones. The incidence of tarsal coalition is approximately 2% in the general population. Talocalcaneal and calcaneonavicular coalitions are the most common. The talonavicular coalition is a rare entity with an incidence of approximately 1.3% among patients with tarsal coalitions. We present a case of a 12-year-old girl who had talonavicular and talocalcaneal coalitions associated with a recurrent ankle sprain. The talonavicular coalition was asymptomatic, and the talocalcaneal coalition was the cause of ankle pain and recurrent sprain. Surgical resection of the talocalcaneal coalition led to successful clinical and functional outcomes. In conclusion, the possibility of multiple tarsal coalitions should be considered in tarsal coalition patients, and the talocalcaneal coalition should be considered as a differential diagnosis in an adolescent patient with a recurrent ankle sprain.

Coalizão da articulação talocalcaneana com Os sustentaculum - Uma coalizão incomum / Coalition of the medial portion of the talocalcaneal with the associated Os sustentaculum – An uncommon coalition

Introdução: O Os sustentaculum é um osso acessório raro localizado na extremidade posterior do sustentaculum tali. A coalizão tarsal pode ser considerada uma anomaliacongênita que pode se tornar sintomática. Frequentemente, é necessária a TC ou a RM para confirmar o diagnóstico de coalizão talo-calcânea quando os achados nas radiografiassão ambíguos. Objetivo: Relatar um caso incomum de Coalizão da articulação talocalcaneana com Os sustentaculum, diagnosticado por exames de imagem. Relatodo Caso: Mulher de 26 anos com “caroço” no tornozelo direito há 10 anos promovendo dor intermitente. Apresenta piora ao usar salto – independentemente do tempo, ao andar ou ao ficar em posição ortostática por mais de 1 hora, referindo dor a palpação e irradiação para o pé. A radiografia do tornozelo direito apresenta ossículo acessório na porção medial da articulação talo-calcânea – Os sustentaculum, confirmada pela tomografia computadorizada. A ressonância magnética diagnostica coalizão talo-calcânea extra-articular com Os ustentaculum. Conclusão: É importante ressaltar que o Os sustentaculum não é apenasum ossículo acessório ou uma fratura antiga, ele é um componente de um tipo de coalizão talo-calcânea extra-articular, o que faz com que essa condição seja geralmente sintomática. Portanto, se um paciente com Os sustentaculum apresentar sintomas na área articular talo-calcânea medial, uma coalizão talo-calcânea extra-articular com Os sustentaculum deve ser considerada. Palavras-chave: Coalizão tarsal, Tomografia computadorizada por raios X, Imagem por ressonância magnética, Radiografia ABSTRACT Introduction: The Os sustentaculum is a rare accessory bone located at the posterior end of the sustentaculum tali. The tarsal coalition can be considered a congenital anomaly that can become symptomatic. Often, CT or MRI is required to confirm the diagnosis of the talo-calcaneus coalition when the findings on radiographs are ambiguous. Objective: To report an unusual case of a coalition of the talocalcaneal joint with Os sustentaculum, diagnosed by imaging exams. Case Report: A 26-year-old woman with a “lump” in her right ankle for 10 years causing intermittent pain. She worsens when wearing heels - regardless of the time when walking or standing in an orthostatic position for more than 1 hour, referring to pain on palpation and irradiation to the foot. The right ankle radiograph shows an accessory ossicle in the medial portion of the talocalcaneal joint – Os Sustentaculum, confirmed by computed tomography. Magnetic resonance imaging diagnoses extra-articular talo-calcaneus coalition with Os sustentaculum. Conclusion: It is important to emphasize that the Os sustentaculum is not just an accessory ossicle or an old fracture, it is a component of a type of extra-articular talo-calcaneus coalition, which makes this condition generally symptomatic. Therefore, if a patient with Os sustentaculum shows symptoms in the medial talo-calcaneus joint area, an extra-articular talo-calcaneus coalition with Os sustentaculum should be considered. Keywords: Tarsal coalition, X-ray computed tomography, Magnetic resonance imaging, Radiography

Clinical and functional outcomes of tarsal coalition resection to correct rigid flat foot

Objective: This study used the AOFAS score to assess the clinical functional results of patients who underwent tarsal coalition resection. Methods: This was a retrospective case series of patients who underwent tarsal coalition resection to correct rigid flat foot. Clinical and functional assessment was performed with the AOFAS score before and 6 months after surgical treatment. Descriptive analysis was performed for 7 patients (11 operated feet) using measurements of position and dispersion (mean, standard deviation, minimum, median and maximum value) for continuous variables and frequency tables (absolute and relative) for categorical variables. Results: The mean patient age was 10 years, 7 months, and the majority (71.43%) were male. The most affected joint was the calcaneonavicular. The right side was affected in 54.55% of the cases. The most frequent type of coalition was osseous (81.82% of the cases). The mean pre- and postoperative AOFAS scores were 32.7 and 70.2 points, respectively, which was a significant increase. Conclusion: The increased scores after coalition resection was considered the main change between the two assessments. Thus, it can be concluded that in rigid flat feet without severe hind- or forefoot deformities for which conservative treatment failed, bar resection should be the surgical procedure of choice. Level of Evidence IV; Therapeutic Studies; Case Series.

GDF6 Knockdown in a Family with Multiple Synostosis Syndrome and Speech Impairment

Multiple synostoses syndrome type 4 (SYNS4; MIM 617898) is an autosomal dominant disorder characterized by carpal-tarsal coalition and otosclerosis-associated hearing loss. SYSN4 has been associated with GDF6 gain-of-function mutations. Here we report a five-generation SYNS4 family with a reduction in GDF6 expression resulting from a chromosomal breakpoint 3′ of GDF6. A 30-year medical history of the family indicated bilateral carpal-tarsal coalition in ~50% of affected family members and acquired otosclerosis-associated hearing loss in females only, whereas vertebral fusion was present in all affected family members, most of whom were speech impaired. All vertebral fusions were acquired postnatally in progressive fashion from a very early age. Thinning across the 2nd cervical vertebral interspace (C2-3) in the proband during infancy progressed to block fusion across C2-7 and T3-7 later in life. Carpal-tarsal coalition and pisiform expansion were bilaterally symmetrical within, but varied greatly between, affected family members. This is the first report of SYNS4 in a family with reduced GDF6 expression indicating a prenatal role for GDF6 in regulating development of the joints of the carpals and tarsals, the pisiform, ears, larynx, mouth and face and an overlapping postnatal role in suppression of aberrant ossification and synostosis of the joints of the inner ear (otosclerosis), larynx and vertebrae. RNAseq gene expression analysis indicated >10 fold knockdown of NOMO3, RBMXL1 and NEIL2 in both primary fibroblast cultures and fresh white blood cells. Together these results provide greater insight into the role of GDF6 in skeletal joint development.

ASSESSING THE ACCURACY, QUALITY, AND READABILITY OF ONLINE PATIENT RESOURCES ON TARSAL COALITION

Background: The internet is an inexpensive and convenient source for health information. However, without regulation, the quality and accuracy of the information is unknown. Tarsal coalition is a common cause of pediatric foot pain and disability. Hypothesis/Purpose: We hypothesized that the online patient information on tarsal coalition is of low accuracy, low quality, and of poor readability. Additionally, we hypothesized that sources found on the first search page were of higher quality, greater accuracy, and more readable. Methods: A cross-sectional review of the internet was performed using the term “tarsal coalition” on the 3 most popular search engines. Unique sites were categorized based on authorship and search result order. Websites were evaluated using a novel content score based on the AAOS OrthoInfo site on tarsal coalition (max score: 20), JAMA Benchmark and DISCERN scores for quality, and Flesch-Kincaid Grade Level (FKGL) and Flesch Reading Ease (FRE) for readability. Results: A total of 47 unique websites were evaluated. They ranged from professional organization/society websites to websites for individual practices and professional blogs. The average content score was 13.1 (range: 4-20). The average DISCERN score was 34.2 (range: 19-57.5). We did find a positive correlation between the content score and DISCERN scores of the included resources (p=0.04). The average 11.4 (range 8.5-15.5). Only 2 of the websites (4%) were written at or below an 8th grade reading level, which has been documented as the average reading level of the general population in the United States. Websites that were authored by physicians had greater DISCERN and readability scores compared to academic and private practice websites (DISCERN 40.4 vs 32.3 (p=0.001) and 31.7 (p=0.01), respectively, FKGL 13.0 vs 10.4 (p=0.002) and 11.1 (p=0.03), respectively, FRE 31.5 vs 48.7 (p=0.0001) and 45.2 (p=0.025), respectively). Finally, we noted that websites which appeared on the first page of the search engine results were not of higher quality than those that appeared on later pages (DISCERN 32.6 vs 39.8, p=0.002). Conclusions: Online patient resources on tarsal coalition are of low quality, inaccurate, and too complex for the average reader. Physician authored websites may serve as better resources compared to academic or private practice sites. Physicians should caution patients using the internet for information on tarsal coalition.