Quadratus plantae Muscle Anatomy

Quadratus plantae Muscle is one of the 2nd layer of the foot along with long flexor tendons and four lumbricals. The lateral plantar vessels and nerve separate the Quadratus plantae from the muscles of the first layer of the foot.

Quadratus plantae Muscle Anatomy

The Quadratus plantae muscle arise with two heads from the medial and lateral calcaneus:

1. The medial head (the muscular head) arises from the medial concave surface of the calcaneus.
2. The lateral head (flat and tendinous), arises from the lateral border of the inferior surface of the calcaneus, in front of the lateral process of its tuberosity, and from the long plantar ligament.

The two heads joins together as flattened band that is inserted into the lateral margin and upper and under surfaces of the tendon of the flexor digitorum longus tendons.

See Also: Foot Anatomy

During a routine dissection in the Department of Anatomy at Kerman University of Medical Sciences, a variant plantar muscle was observed in a 40-year-old male cadaver. In the present case, we report a rare variation associated with the insertion pattern of this muscle, which is reported for the first time in Iran. The tendinous end of the QP muscle was divided into three tendons and were then inserted to the inferior surface of 2nd, 3rd and 4th tendons of FDL.

This muscle is innervated by the lateral plantar nerve and is supplied by the lateral plantar artery.

The Quadratus plantae Muscle acts and helps to flex distal phalanges.

References & More

1. Clinically Oriented Anatomy – 8th Edition
2. Haratizadeh S, Seyyedin S, Nematollahi-Mahani SN. Anatomical variation of quadratus plantae in relation to flexor hallucis longus and flexor digitorum longus: a rare case. Folia Morphol (Warsz). 2023;82(2):412-415. doi: 10.5603/FM.a2022.0034. Epub 2022 Apr 5. PMID: 35380012. Pubmed