Groove for tendon of tibialis posterioris muscle of navicular bone

The groove for the tendon of the tibialis posterior muscle on the navicular bone is located on the plantar and medial aspect of the navicular. This groove accommodates the tibialis posterior tendon as it courses to its primary insertion on the navicular tuberosity.

The median length of this groove is approximately 16–18 mm, with some variation between right and left sides, but no significant difference in overall morphometry between sides.

The groove is typically situated just inferior to the navicular tuberosity, running obliquely from proximal-medial to distal-plantar, and serves to stabilize the tendon as it transitions from its retromalleolar course to its insertion. The groove is lined by fibrocartilage, which is part of the "enthesis organ" at the navicular insertion, providing biomechanical protection and reducing stress concentration at the osteotendinous junction.