Abstract
INTRODUCTION: Flexible pes planovalgus in children may be corrected with a calcaneal lengthening osteotomy (CLO).However, CLO surgery may displace the distal calcaneal fragment dorsally and affect the motion in the calcaneal-cuboid joint (CCJ). We used radiostereometric analysis (RSA) to evaluate CCJ motion and CLO stability in children one year after CLO. METHODS: Ten patients (10 feet) with symptomatic flexible pes planovalgus were investigated one year after CLO. Mean age was 11.5 years (range 8.2-14.2). Standardised RSA measurements of the foot were obtained one year after surgery without and with weight-bearing (single leg stance). Tantalum markers inserted during surgery, were used to described the CCJ motion as cuboid bone motion with respect to the distal calcaneus, and the CLO stability as distal calcaneal migration with respect to the proximal calcaneus. RESULTS: One year after surgery the CLO was stable. The motion in the CCJ upon full weight-bearing was mean -1.04 mm (CI95% -1.40; -0.67) joint distraction, mean 2.27 mm (CI95% 1.57; 2.96) cuboid dorsal translation, mean -1.94 mm (CI 95% -2.68; -1.20) cuboid medial translation, and mean 7.43° (CI 95% 3.97; 10.88) adduction. CONCLUSION: The motion in the CCJ of children with CLO corrections for pes planovalgus is similar to that of adults during stance load with a normal foot posture and the patients were asymptomatic. Marker-based RSA may be used to evaluate causalities of foot symptoms after CLO surgery.