Effective zone of botulinum toxin a injections in hallux claw toe syndrome: an anatomical study.

INTRODUCTION: The aim of this study was to determine the anatomical location of the motor points of the flexor hallucis longus (FHL) and brevis (FHB) muscles for an effective motor point block.

METHODS: Twenty cadavers were used for this study. For the FHL, we identified the line between the medial and lateral epicondyle of the femur and the line joining the prominent point on the surface of the medial malleolus of the tibia and the lateral malleolus of the fibula. For the FHB, we identified the line between the middle-lowest point of the great toe and the middle-lowest point of the sole of the foot.

RESULTS: The dense area of the motor points was located at 40-70% for the FHL and 50-70% for the FHB.

CONCLUSION: An injection area of 50-60% on the reference line for the FHL and FHB is suggested.