NATA BOC Domain 2 Clinical Evaluation & Diagnosis Special Test Practice

The first metatarsal rise sign assesses the function of the tibialis posterior tendon. This tendon is the main dynamic stabilizer of the medial arch, helping to invert the foot and maintain the alignment of the hindfoot and the first ray during stance and push-off. When tibialis posterior is functioning properly, it helps keep the first metatarsal from rising as the foot plantarflexes or when rising onto the toes. If the tendon is injured or incompetent, the first metatarsal is more likely to rise due to unopposed forces acting on the first ray, producing a positive sign. Other tendons like peroneus longus, flexor digitorum longus, or extensor hallucis longus don’t play the primary stabilizing role for the medial arch and first ray in this test, so the sign specifically points to tibialis posterior integrity.