Collateral interphalangeal ligaments of foot
Ligamenta interphalangea collateralia pedis
Paired fibrous bands on the two sides of each joint between the bones of the toes, keeping these hinge joints aligned.
At a glance
- English
- Collateral interphalangeal ligaments of foot
- Latin (TA2)
- Ligamenta interphalangea collateralia pedis
- System
- Ligament
- Region
- Foot
- Side
- Paired, left and right
About the collateral interphalangeal ligaments of foot
Each lesser toe has two interphalangeal joints, one between the proximal and middle phalanges and one between the middle and distal phalanges; the big toe has only one. All are hinge joints that let the toe bend and straighten but not move from side to side. That restriction is the job of the collateral interphalangeal ligaments, one on each side of every joint.
Each ligament is a strong, slightly fan-shaped band. It starts from a small pit or tubercle on the side of the head of the more proximal phalanx and runs downwards and forwards to the side of the base of the next phalanx. Part of it, sometimes called the accessory collateral ligament, fans out to the edges of the plantar ligament (plantar plate), a thick fibrocartilage pad on the underside of the joint. The collateral ligaments, the plantar ligament and the thin joint capsule together make a box around the joint. On the top there is no separate ligament; the extensor tendons and their expansion take its place.
Because their attachment is above and behind the centre of rotation, the collateral ligaments are tighter in some positions than others, which stabilises the toe during push-off when the joint is loaded. They prevent sideways bending and twisting at the joint and keep the joint surfaces in line.
Stubbing a toe or catching it on furniture can sprain or tear one of these ligaments, leaving a swollen, painful joint that may dislocate sideways. Long-standing imbalance of the toe muscles stretches the capsule and ligaments and contributes to deformities such as hammer and claw toes.
Attachments and function
- Attaches from
- The sides of the head of the more proximal phalanx at each interphalangeal joint.
- Attaches to
- The sides of the base of the next phalanx and the margins of the plantar ligament.
- Function
- Stops sideways and twisting movement at the toe joints between phalanges while allowing flexion and extension.
- Nerve supply
- Digital branches of the medial and lateral plantar nerves, and dorsal digital nerves on the upper side.
- Blood supply
- Branches of the plantar and dorsal digital arteries.
Anthromica
See the collateral interphalangeal ligaments of foot where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
