Sagittal plane blocade in patients with Functional Hallux Limitus:a multisegment model analysis of the Flexor Hallucis Longus endoscopic tenolysis

Functional Hallux Limitus (FHL) is a relatively unknown clinical entity in which dorsal flexion of the first metatarsophalangeal joint is restricted during final stance phase, derailing the three mechanisms of foot stabilization 1. The close packing of the calcaneocuboid joint; 2. The Windlass mechanism and 3. The locked wedge effect mechanism.These failures cause a sagittal plane blockade leading to an asynchronic and mistimed gait characterized by increased ankle, knee and hip flexion associated to increased anterior pelvic tilt. It also causes alterations in the frontal and axial anatomic planes. We prospectively studied a cohort of 20 patients treated with endoscopic tenolysis of Flexor Hallucis Longus (Fhl) tendon and by use of a a multi-segment model consisted of Gait and joint angles' analysis. Our promising results regarding the correction of this condition by an endoscopic retrotalar release that restores normal gait biomechanics warrant larger patient cohorts in order to be further supported.