A Unique Variation of Quadratus Plantae in Relation to the Tendons of the Midfoot

Abstract

A novel combination of variations involving the quadratus plantae muscle (QP) and its relationship to the flexor hallucis longus (FHL) tendon was observed unilaterally in the right foot of an 88-year-old female cadaver during routine dissection. The medial head of QP was observed inserting onto the tendon of FHL rather than the tendon of flexor digitorum longus (FDL), while also contributing to an anomalous tendinous slip to the second digit in conjunction with the tendon of FHL. The tendon of FHL also gave off a slip to the third digit. Both tendinous slips attached distally to the digital tendons of FDL. Lastly, the lateral head of QP inserted onto the tendinous slip from FHL to the third digit. Ninety-five additional feet were assessed for these variations, but none were observed. This combination of variations expands upon the proposed actions of QP in the literature. Furthermore, connections between the tendons of the midfoot are of clinical significance for harvesting tendon grafts.

Anatomical variation of quadratus plantae in relation with flexor digitorum brevis

“…According to Coomar et al [ 14 ] the QP was inserted into the FHL and two tendinous slips arose from the medial head of QP & FHL and were inserted into the FDL at the level of metatarsophalangeal joints and the lateral head of QP was inserted into the second tendinous slip which changes the normal action of these muscles.…”

“…According to Coomar et al [14] the QP was inserted into the FHL and two tendinous slips arose from the medial head of QP & FHL and were inserted into the FDL at the level of metatarsophalangeal joints and the lateral head of QP was inserted into the second tendinous slip which changes the normal action of these muscles. This is the first cadaveric report of a combination of all the above-mentioned variations especially the thin tendon of QP was inserted into the second tendon of FDB and it may lead to the compression of neurovascular structures and mimics the tarsal tunnel syndrome.…”

Anatomical Variations of Flexor Muscles in Sole

“…The FDAL is intimately related to the neurovascular bundle and may abut, compress, or impinge upon the posterior tibial and/or lateral plantar nerves. Accessory muscles of the ankle are typically asymptomatic, but can cause pain, compressive neuropathy, compartment syndrome, or rigid hind foot deformities, and can also mimic soft tissue tumors [13][14][15][16][17][18]. The flexor hallucis longus (FHL) and flexor digitorum longus (FDL) tendon are routinely used in reconstructive foot and ankle surgery [20].…”