A bipartite medial cuneiform is an anatomical variant where there are two ossification centers involving the medial cuneiform. In many cases the overall shape of the medial cuneiform is conserved, although the size of the two combined bones is larger than that of a normal medial cuneiform.
The estimated incidence is thought to be around 0.1% of the general population.
Some patients may have additional associations which include:
- os intermetatarseum
- accessory navicular bone
- spinal segmentation anomalies
- lunotriquetral coalition
- an accessory temporal bone suture
- bipartite temporal bone
Most patients are asymptomatic although occasionally some patients can present with pain.
A lateral radiograph (30 degree angled) may give an "E" sign with the two bones most often dorsal and plantar viewed end on.
May also give an E sign when viewed on sagittal images. MRI also allows direct visualization of anatomy as well as appreciation of any signal abnormality along the synchondrosis.
Treatment and prognosis
Symptomatic cases may benefit from intervention ranging from various nonoperative measures to surgical excision.
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