The interphalangeal joints of the foot are between the

phalanx bone The phalanges (singular: ''phalanx'' ) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bon ...

s of the

toe Toes are the digits (fingers) of the foot of a tetrapod. Animal species such as cats that walk on their toes are described as being ''digitigrade''. Humans, and other animals that walk on the soles of their feet, are described as being ''plan ...

s in the

feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...

. Since the

great toe Toes are the digits (fingers) of the foot of a tetrapod. Animal species such as cats that walk on their toes are described as being '' digitigrade''. Humans, and other animals that walk on the soles of their feet, are described as being '' pl ...

only has two phalanx bones (proximal and distal phalanges), it only has one interphalangeal joint, which is often abbreviated as the "IP joint". The rest of the toes each have three phalanx bones (proximal, middle, and distal phalanges), so they have two interphalangeal joints: the proximal interphalangeal joint between the proximal and middle phalanges (abbreviated "PIP joint") and the distal interphalangeal joint between the middle and distal phalanges (abbreviated "DIP joint"). All interphalangeal joints are ginglymoid (hinge) joints, and each has a

plantar Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

(underside) and two

collateral Collateral may refer to: Business and finance * Collateral (finance), a borrower's pledge of specific property to a lender, to secure repayment of a loan * Marketing collateral, in marketing and sales Arts, entertainment, and media * ''Collate ...

ligament A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the: * Peritoneal li ...

s. In the arrangement of these ligaments,

extensor In anatomy, extension is a movement of a joint that increases the angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extendin ...

tendons A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...

supply the places of

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

ligaments, which is similar to that in the

metatarsophalangeal articulations The metatarsophalangeal joints (MTP joints), also informally known as toe knuckles, are the joints between the metatarsal bones of the foot and the proximal bones (proximal phalanges) of the toes. They are condyloid joints, meaning that an ellipt ...

Movements

The only movements permitted in the joints of the digits are

flexion Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...

and

extension Extension, extend or extended may refer to: Mathematics Logic or set theory * Axiom of extensionality * Extensible cardinal * Extension (model theory) * Extension (predicate logic), the set of tuples of values that satisfy the predicate * E ...

; these movements are more extensive between the first and second phalanges than between the second and third. The

flexor hallucis longus The flexor hallucis longus muscle (FHL) is one of the three deep muscles of the posterior compartment of the leg that attaches to the plantar surface of the distal phalanx of the great toe. The other deep muscles are the flexor digitorum longus an ...

and

flexor digitorum longus The flexor digitorum longus muscle is situated on the tibial side of the leg. At its origin it is thin and pointed, but it gradually increases in size as it descends. It serves to flex the second, third, fourth, and fifth toes. Structure The fl ...

flex the interphalangeal joint of the big toe and lateral four toes, respectively. The tendons of both of these muscles cross as they reach their distal attachments. In other words, the flexor hallucis longus arises laterally, while the flexor digitorum longus arises medially. The amount of flexion is very considerable, but extension is limited by the

and collateral ligaments. Gray269

References

Joints Foot {{musculoskeletal-stub

Movements

See also

References