Radiological and podographic results of calcaneal lengthening osteotomy in children with pes planus: Retrospective evaluation

This study aims to evaluate agreement between radiological results and podographic measurements to classify feet on the basis of the medial longitudinal arch (MLA) in patients who had calcaneal lengthening osteotomy due to symptomatic hypermobile pes planus in childhood. Retrospective study included 30 feet with calcaneal lengthening osteotomy. Ten different radiological measurement methods were used. OxAFQ-C questionnaire was applied for clinical assessment. Arch index, footprint index and clarke angle were used for podographic measurements. Agreement on classifying of foot type (normal/abnormal) between radiological and podographic measurements were evaluated by Cohen's kappa statistics. OxAFQ-C results were compared with radiological and podographic measurements. The average age was 15.1 years (11-17). Significant change was observed in calcaneus length and posterior facet height (p<0.05). Arch index and MLA radiological measurements had the statistical agreement for classifying of the foot postoperatively. Strength of agreements between arch index with lateral talo-1.metatarsal (k=0.902) angle and talohorizontal angle(k=0.814) were perfect. MLA radiological measurements had no agreement with clarke angle and footprint index (p>0.05). No agreement found between the three types of podographic measurements. Arch Index and lateral talo-1.metatarsal angle were only methods which had correlation with all domains of the clinical questionnaire (p<0.05). In conclusion, following calcaneal lengthening osteotomy, arch index, among the other podographic measurement methods, can be used to classify the foot and the clinical satisfaction level instead of MLA radiological measurements, whereas clarke angle and footprint index don't give predictable results.