Description

Pain and/or inflammation (with minimal or no radiographic change) of one or both of the two sesamoid bones embedded in the flexor hallucis brevis tendon under the 1st metatarsophalangeal (MTP) joint

Etiology and Pathophysiology

• Pain results from repetitive, increased forefoot weight-bearing stresses or forceful dorsiflexion of the great toe.
• May also be caused by fracture, stress fracture, infection, inflammatory arthropathies, congenital deformity to the sesamoid(s), and osteoarthritis in the absence of repetitive trauma

Genetics
No known genetic predisposition

Risk Factors

• Athletes who repetitively put significant load on the sesamoids are at particular risk, such as the following:
  • Long-distance runners
  • Ballet dancers
  • Baseball catchers
• Acquired peroneal dysfunction/tightness
• Abnormal first ray range of motion
• Decreased 1st MTP motion (hallux limitus/rigidus)
• Congenital factors increase the risk of injury.
  • Asymmetry in the size of the sesamoid bones
  • Malalignment of the sesamoid bones
  • Supinated or pronated foot type
  • Forefoot valgus, plantar flexed first ray
  • Decreased ankle dorsiflexion
  • Cavus feet (high arch)

General Prevention

Sesamoiditis is most commonly an overuse injury; activity modification is key to prevention.