ABSTRACT
Objective: To explore the evaluation effect of ultrasonography and Pirani score on tarsal deformity, treatment effect and pseudo-correction of congenital clubfoot in infants and young children, and the correlation between the two methods. Methods: This is a retrospective case series study. The clinical data of 26 children (40 feet) with congenital clubfoot who were evaluated by ultrasonography in the Third Affiliated Hospital of Zhengzhou University from January 2020 to January 2023 were retrospectively collected. There were 16 males and 10 females. The age at the first ultrasound examination was (M(IQR)) 9.0 (18.0) days (range: 1 to 46 days). All patients were treated with Ponseti method by the same physician. The Pirani scores before and after treatment and at the last examination, and the talonavicular angle, calcaneocuboid angle and tibiocalcaneal angle measured by ultrasound were collected, and the treatment and follow-up were recorded. Paired sample t test, repeated measures analysis of variance or Kruskal-Wallis test were used for data comparison, and Spearman correlation analysis was used for correlation analysis. The receiver operating characteristic curve was used to calculate the efficacy of ultrasound in evaluating different Pirani scores. Results: The number of plaster fixation in 26 children was 4.0 (1.0) times (range: 2 to 8 times). The medial talonavicular angle and posterior tibiocalcaneal angle were significantly improved after treatment and at the last follow-up compared with those before treatment, and the differences were statistically significant (all P<0.01). There was no difference in lateral calcaneocuboid angle before and after treatment and at the last follow-up (F=1.971, P>0.05). Pseudo-correction occurred in 2 cases (2 feet) during the treatment, with an incidence of 5%. Correlation analysis showed that there was a moderate positive correlation between talonavicular angle and Pirani midfoot score (r=0.480, P<0.01). There was no correlation between calcaneocuboid angle and Pirani midfoot score (r=0.114, P=0.105). There was a moderate negative correlation between tibial heel angle and Pirani hindfoot score (r=-0.566, P<0.01). The cut-off point of Pirani midfoot score of 1.5 was 38.78°, the sensitivity was 0.90, the specificity was 0.56, and the area under the curve was 0.75. The cut-off value of angle was 27.51 °, the sensitivity was 0.16, the specificity was 0.92, and the area under the curve was 0.44.The cut-off points of Pirani midfoot score of 3.0 were 45.08°and 9.96°, the sensitivity was 0.94 and 0.91, the specificity was 0.37 and 0.42, and the area under the curve was 0.59 and 0.62, respectively. The cut-off values of Pirani hindfoot score of 2.0 and 3.0 were 167.46° and 160.15°, respectively. The sensitivity was 0.75 and 0.67, the specificity was 0.81 and 0.83, and the area under the curve was 0.78 and 0.71, respectively. Conclusion: Ultrasound can complement with Pirani score, visually and dynamically observe the morphology and position changes of talonavicular joint, calcaneocuboid joint and tibiotalocalcaneal joint, monitor the recovery and pseudo-correction of tarsal bones, and better evaluate the therapeutic effect.