Plantar Plating in the Modified Lapidus Procedure: Evaluation of Function and Impairment of the Tibialis Anterior Tendon.

The modified "Lapidus" procedure (MLP) describes the arthrodesis of the first tarsometatarsal joint. We investigate if there are detectable changes of the tendon or the function of the muscle and clinical outcome after MLP. We reviewed 22 feet. All patients underwent magnetic resonance imaging (MRI) at an average of 27 (range, 12-49) months. Clinical outcome was evaluated using the European Foot and Ankle Society score. Strength was measured and complications were assessed. MRI revealed signs of tendinopathy of the tibialis anterior tendon in 13 feet (59%). The mean total European Foot and Ankle Society score at final follow-up was 17 (range, 6-24) points. The mean postoperative Visual Analog Scale score was 1.4 (range, 0-5). Range of motion and force data were not significantly different to the contralateral side. In conclusion, MRI showed signs of tendinopathy in 59%, which does not seem to affect clinical outcome, but has to be considered when choosing the desired implant and placement. MLP leads to high patient satisfaction rates and significant improvement at midterm follow up.