Sesamoid Fracture (broken sesamoid)

Sesamoid fractures are seen in ballet dancers and runners secondary to repetitive hyperextension at the MTP joints.

These fractures are usually the result of a direct force applied to this area of the foot either from a fall with landing on the metatarsal heads or from a weight being dropped on the foot. Occasionally, these injuries occur as avulsion fractures from forceful hyperextension of the great toe or from traction injuries to the flexor hallucis brevis.

The sesamoids are an integral part of the capsuloligamentous structure of the first MTP joint. They function within the joint complex as both shock absorbers and fulcrums in supporting the weight-bearing function of the first toe. The sesamoid bone ligament complex of foot contains two sesamoid bones one medial tibial sesamoid and other lateral fibular sesamoid bone, both embedded in the plantar ligament beneath first metatarsal head.

See Also: Foot Anatomy

Sesamoid Fracture Diagnosis

The patient with a broken sesamoid presents with localized pain over the area, with accentuation of symptoms with passive extension or active flexion of the MTP joint.

Anteroposterior, lateral and oblique views of the forefoot are usually sufficient to demonstrate a transverse fracture of the sesamoids. Occasionally, a tangential view of the sesamoids is necessary to visualize a small osteochondral or avulsion fracture. This must be differentiated from a congenital bipartite sesamoid which is seen in 10–30% of people with an 85% bilateral occurrence.

Local pain and irregularity on the radiograph are the distinguishing features for a fracture. It is sometimes difficult to visualize on plain radiographs and a CT may be needed.

Technetium bone scanning or MRI may be used to identify stress fractures not apparent by plain radiography.

See Also: Calcaneus Fracture (Heel Fracture)

Sesamoid Fracture Treatment

Non-operative management should initially be attempted, with soft padding combined with a short leg walking cast for 4 weeks followed by a shoe with a metatarsal pad for 4–8 weeks. If pain persists, a sesamoid resection with reconstitution of the tendon is indicated.

Symptomatic nonunion of Sesamoid Fracture is a common problem after nonoperative treatment. Surgical fixation of the fracture can result in successful union, but is technically challenging and can be associated with prolonged return to activities (RTA). Sesamoidectomy is an alternative surgical option that may provide reliable outcomes and allow an earlier RTA in athletes.

References & More

1. Mercer’s Textbook of Orthopaedics and Trauma, Tenth edition.
2. Bichara DA, Henn RF 3rd, Theodore GH. Sesamoidectomy for hallux sesamoid fractures. Foot Ankle Int. 2012 Sep;33(9):704-6. doi: 10.3113/FAI.2012.0704. PMID: 22995255. Pubmed
3. Daddimani RM, Madhavamurthy SK, Jeevannavar SS, Shettar CM. Fracture of the medial tibial sesamoid bone of the foot-case report. J Clin Diagn Res. 2015 Apr;9(4):RD03-4. doi: 10.7860/JCDR/2015/12899.5831. Epub 2015 Apr 1. PMID: 26023612; PMCID: PMC4437128. Pubmed