The effects on subtalar contact and pressure following talonavicular and midtarsal joint arthrodesis

Many clinical studies have demonstrated the effectiveness of both isolated talonavicular and complete midtarsal joint arthrodesis as an alternative to triple arthrodesis. However, in many cases, controversy exists as to which procedure to utilize. Evidence of degenerative radiographic changes and stiffness of the subtalar joint have been reported postoperatively. A cadaveric study at two different loading values, utilizing low-range pressure film transducers and digital scanning, was performed to quantify articular contact effects on the subtalar joint following isolated talonavicular joint arthrodesis and complete midtarsal joint arthrodesis as compared to the intact specimen. Statistically significant differences were found at p < .05 in this study regarding maximum contact pressure and in location of the applied pressures. Results of this study suggest complete midtarsal joint arthrodesis may be favored over isolated talonavicular joint arthrodesis, especially in the setting of a flatfoot deformity.