Anat Cell Biol.  2025 Mar;58(1):132-135. 10.5115/acb.24.194.

Anatomical variation of quadratus plantae with flexor digitorum longus tendon along with unilateral polydactyly of the toes: a rare case report

• Krishna H
• Gaur R
• Gupta S
• Ghatak S

• KMID: 2565965
• DOI: http://doi.org/10.5115/acb.24.194

Abstract

During routine dissection, we observed a unique case of unilateral polydactyly in the left foot of a 61-year-old male cadaver. We observed the medial head of the quadratus plantae (QP) muscle, which gave off an additional tendinous slip before joining the lateral head of QP. The 4th tendon of the flexor digitorum longus (FDL) was bifurcated into two tendinous parts after receiving a thin fibrous slip from the tendinous slip of the medial head of QP. The medial division of the 4th tendon of FDL passed forward and attached to the base of the distal phalanx of the 5th toe. The extra tendinous slip from the medial head of QP was attached distally to the lateral division of the 4th tendon of FDL and formed a common anomalous tendon to the 6th toe. The knowledge of this variation would be helpful in reconstructive foot surgeries and correction of congenital deformities.

Keyword

Quadratus plantae; Flexor digitorum longus; Foot; Tendons; Toes

Figure

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  Fig. 1 Photographs of the sole showing (A) polydactyly and the flexor tendon to the 6th toe derived from both FDL and medial head of QP in the left foot, and (B) enlarged view of (A). Red arrow shows the thin tendinous connection from QP to the 4th tendon of the FDL. Yellow arrow shows the formation of the common anomalous tendon to the 6th toe contributed by QP and FDL. 1, flexor tendon to the 1st toe; 2, flexor tendon to the 2nd toe; 3, flexor tendon to the 3rd toe; 4, flexor tendon to the 4th toe; 5, flexor tendon to the 5th toe; 6, flexor tendon to the 6th toe; FHL, flexor hallucis longus; FDL, flexor digitorum longus; QP, quadratus plantae; M, medial; L, lateral; A, anterior; P, posterior.

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  Fig. 2 Schematic diagram showing the formation of the common anomalous tendon to the 6th toe (arrow). A, anterior; P, posterior; M, medial; L, lateral; QP, quadratus plantae; FDL, flexor digitorum longus; FHL, flexor hallucis longus.

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  Fig. 3 (A) Dorsal view and (B) plantar view of bones of the foot showing additional 6th metatarsal and phalanges. 1, 1st metatarsal; 2, 2nd metatarsal; 3, 3rd metatarsal; 4, 4th metatarsal; 5, 5th metatarsal; 6, 6th metatarsal; A, anterior; P, posterior; M, medial; L, lateral; Cal, calcaneum; T, talus; N, navicular; Cun, cuneiform; Cub, cuboid; p, phalanges.

Reference

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