sesamoiditis

Sesamoiditis (rare plural: sesamoiditides) is an inflammatory condition involving the sesamoid bones, usually a diagnosis of exclusion once other causes for sesamoid pain have been excluded.

The term is almost exclusively used in reference to the hallux sesamoids and this will be the focus of this article.

Epidemiology

Typically occurs in young women.

Clinical presentation

Patients can present with non-specific metatarsal pain, usually during the toe-off phase of gait. They may weight bear on the lateral aspect of the affected foot due to the pain.

On examination, there can be restricted and painful movement at the great toe metatarsophalangeal joint with localizing tenderness to the sesamoids.

Pathology

Occurs secondary to repetitive injury to the plantar aspect of the forefoot.

Radiographic features

Plain radiograph

Radiography is essentially used to look for other bony causes of pain from the great toe and sesamoids. An axial sesamoid view provides a good view of both sesamoids in profile.

Late sesamoiditis can present with changes like fragmentation and sclerosis of the sesamoids which may be non-specific and difficult to distinguish from other causes of sesamoid injury.

CT

• if subtle sclerotic changes are seen, osteonecrosis is more likely than sesamoiditis

MRI

• bone marrow edema within one or both of the great toe sesamoids
  • STIR: high signal
  • T1: normal or low signal
• may be indistinguishable from osteonecrosis early in the disease
• can exclude MTP joint osteoarthritis and other causes of pain
• sesamoiditis is often associated with reactive soft tissue changes, e.g. tenosynovitis, synovitis, bursitis

Nuclear medicine

Bone scintigraphy (Tc-99m)

• focally increased sesamoid tracer uptake

Treatment and prognosis

Conservative management may be trialled initially with the use of foot padding, taping of the toe in plantar flexion and orthotic shoes.

Ultrasound-guided steroid and local anesthetic injection of the sesamoid-metatarsal articulation can be therapeutic and diagnostic. However, this is contraindicated if there is a known sesamoid fracture or suspected avascular necrosis.

Sesamoidectomy is reserved for patients with refractory pain despite other measures.

Differential diagnosis

• avascular necrosis
• fracture
• stress response

Siehe auch:

• Sesambein

und weiter:

• Sesambeine des Fußes
• sesamoiditis os peroneum
• medial hallux sesamoiditis