Pain involving the hallux sesamoid bone is commonly referred to as sesamoiditis. This condition is often seen in athletes, representing 2.2% of foot injuries in collegiate athletes.1 A study investigating 683 young athletes presenting to a sports medicine clinic reported that the most common diagnosis for pain localised to the hallux sesamoids was sesamoiditis.2 While a recognised injury, the management strategies reported in the literature are not consistent and include non-surgical management with mixed outcomes3 to surgical excision.4 One explanation for the variability in treatment outcomes is the non-specific diagnostic criteria for sesamoiditis. Injuries to the hallux sesamoid complex may include a variety of plantar first metatarsophalangeal (MTP) conditions—including ‘turf toe’ (if a traumatic mechanism), MTP synovitis or osteoarthritis, bipartite pseudoarthrosis pain, mild chondrosis and subchondral oedema between the sesamoid and first metatarsal head, or bone stress injury (BSI). In this editorial, we present the rationale for reframing the diagnostic framework for sesamoiditis to include a high suspicion for sesamoid BSI.
Why sesamoiditis falls short
The medial and lateral hallux sesamoids function as a fulcrum and pulley for the flexor hallucis brevis tendon, transmitting significant forces during gait, especially during push-off, in which loads can exceed 300% of body weight.5 As a result, activities that demand frequent extension and flexion through the hallux sesamoid complex, such as running, jumping and dancing, expose this area to high repetitive stress. Over time, this mechanical loading may result in cumulative microtrauma within the sesamoid complex. If the sesamoid bone itself is absorbing the stress, then repetitive loading could exceed the remodelling capacity of the bone and lead to a BSI or even a frank fracture. Given the poor definition of sesamoiditis, bone marrow oedema on MRI is currently used as the …

