Metatarsophalangeal (MTP) Joint Definition

Foot with the metatarsophalangeal joints (MTPJ) labeled. Credit: Photo © Terence Vanderheiden, D.P.M.

What is the Metatarsophalangeal Joint - MTPJ?

The joints between the heads of the metatarsal bones and the bases of the proximal phalanges are the metatarsophalangeal joints. The first metatarsophalangeal joint is commonly known as the big toe joint. The little toe joint is known as the fifth metatarsophalangeal joint.

Also Known As: MTP, the ball of the foot, metatarsophalangeal articulations, big toe joint, little toe joint.

Anatomy of the Metatarsophalangeal Joints

The head of each metatarsal bone connects to the proximal phalanx bones of the toes. The metatarsal head is rounded while the phalanx is concave. The first metatarsal (big toe) also articulates with two sesamoid bones on the plantar surface (facing the sole of the foot). There is a thin joint capsule for each of the joints and ligaments that support it.

Conditions Affecting the Metatarsophalangeal Joints

  • MetatarsalgiaThis term is used for any pain in the ball of the foot, but the most common source of pain in this area is the metatarsophalangeal joint.
  • Bunion: Also known as hallux valgus. A bunion is created when the first metatarsophalangeal joint becomes inflamed and tissue and bone grow to form a bump on the outside edge. This can in turn shift affect the second MTP and create a hammer toe.
  • Bunionette: A bunion on the little toe or fifth metatarsophalangeal joint.
  • Turf Toe: When the big toe is hyperextended, such as when playing football, the MTP joint and surrounding ligaments and tissues are injured and the joint may even be dislocated.
  • Rheumatoid Arthritis: Pain in the MTP joint when standing or walking, and morning stiffness can be an early sign of rheumatoid arthritis. Inflammation of the joint in this disease can lead to hammer toe deformities/
  • Foot Osteoarthritis: The big toe MTP joint is one commonly affected.
  • Hammer Toe: A hammer toe is a misalignment of the MTP joint, often of the second toe. Causes include having unusually long toes or an elongated second metatarsal, and they can form after a bunion has shifted the big toe. They can occur in rheumatoid arthritis when fat tissue in the ball of the foot is pushed forward under the toes. Further problems can develop, including corns and reactive adventitial bursas.

Procedures on the MTP Joint

  • First MTP Joint Fusion: This procedure fuses the bones of the big toe and first metatarsal together permanently. It may be performed in cases of arthritis where the joint cartilage has been worn away and the resulting pain is not relieved by conservative methods. It is often performed as a day surgery, but recovery can last six months. Metal screws and, often, a metal plate are used to stabilize the joint.
  • First MTP Joint Replacement: This procedure is done in cases of arthritis to relieve pain that doesn't resolve with conservative treatment. The big toe joint is removed and implants are used to replace it. These may be made of metal or plastic. It differs from fusion in that the implant mimics the action of the original joint.


    "First MTP Joint Fusion", American Orthopaedic Foot & Ankle Society

    "First MTP Joint Replacement," American Orthopaedic Foot & Ankle Society

    Kendrick Alan Whitney, DPM "Metatarsophalangeal Joint Pain," Merck Manual, October 2014.

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