Talonavicular coalitions, a rarely reported fusion between the talus and navicular, are often an incidental radiographic finding that may be asymptomatic or associated with peroneal spasm. The authors present a review of literature and case report based on clinical evaluation and instrumented gait analysis. Specifically, a patient presenting with a bilateral talonavicular coalition was objectively evaluated with kinetic, kinematic, muscle dynamometry, and pedobarographic testing to understand the biomechanical limitations related to this pathology. An excessive passive component of ankle torque, a high first metatarsophangeal joint plantar pressure, and a diminished time in the midstance portion of stance phase were measured and compared to those of healthy individuals.