Branches of the tibial nerve: anatomic variations

Area of Science:

• Anatomy
• Neuroscience
• Surgical Anatomy

Background:

• Clinical diagnosis of tibial nerve lesions can be challenging due to discrepancies between physical examination and electrophysiologic testing.
• Understanding the detailed anatomy of the tibial nerve and its branches is crucial for accurate localization of nerve pathologies.

Purpose of the Study:

• To investigate the anatomic variations of the tibial nerve and its branches in the foot.
• To correlate these variations with potential causes of diagnostic inconsistencies in tibial nerve injuries.

Main Methods:

• Dissection of 20 cadaveric feet (10 pairs).
• Detailed examination of the tibial nerve's bifurcation point and its branching patterns, particularly the calcaneal branches and innervation to the abductor hallucis muscle.

Main Results:

• The tibial nerve bifurcated within 2 cm of the medio-malleolar-calcaneal axis in 90% of specimens.
• Multiple calcaneal branches were observed in 60% of feet.
• Accessory innervation to the abductor hallucis muscle, not originating from the medial plantar nerve, was identified in 20% of cases.

Conclusions:

• Anatomic variations in tibial nerve branching are common and may explain discrepancies in clinical and electrophysiologic assessments.
• The prevalence of multiple calcaneal branches and accessory innervation highlights the complexity of the tibial nerve's anatomy.