Title: Foot Sesamoid injuries<br/>Author: Brian Corwell<br/><a href='http://umem.org/profiles/faculty/294/'>[Click to email author]</a><hr/><p> Sesamoid Injuries</p> <p> </p> <p> Unlike other bones in the human body that are connected to each other at joints, sesamoid bones are only connected via tendons (or are imbedded in muscle).</p> <p> The largest sesamoid bone is the patella.</p> <p> 2 small sesamoid bones lie on the plantar foot near the great toe</p> <p> Sesamoid bones can fracture and the surrounding tendons can become inflamed (sesamoiditis)</p> <p> Traumatic injury is usually due to hyperextension and axial loading</p> <p> Sx: Pain located under the great toe on the ball of the foot (Gradual with sesamoiditis and acutely with a fracture).</p> <p> There may be associated swelling and bruising. Pain with palpation, flexion and extension.</p> <p> The medial/tibial sesamoid is larger, has great weight bearing status and is more commonly injured that its lateral counterpart.</p> <p> In many people (10 - 25%) the medial sesamoid of the foot has two parts (bipartite). This finding is bilateral in 25% of people.</p> <p> This may confuse some providers as it may appear to be a fracture</p> <p> Look for a smooth contour to the bones and clinically correlate (bruising, soft tissue swelling, etc.) if it is an incidental finding.</p> <p> Other radiographic clues include</p> <p> 1) The fractured sesamoid is usually slightly larger than the lateral sesamoid while the bipartite sesamoid has a much larger medial sesamoid than lateral sesamoid</p> <p> 2) The fractured sesamoid shows a sharp, radiolucent, uncorticated line between the two fragments while the bipartite sesamoid has two corticated components</p> <p> 3) The fractured sesamoid fragments often fit together like pieces of a puzzle while the bipartite sesamoid has two components that do not fit together snugly</p> <p> 4) Other means to differentiate the two involve MRI and bone scanning</p> <p> </p> <p> Treatment involves a stiff-soled shoe or applying a cushioning pad or J-shaped pad around the area to relieve pressure.</p> <p> It may take months for the pain to subside.</p> <p> </p> <p> http://www.apfmj-archive.com/afm5_3/afm50.htm#F1</p> <p> </p> <fieldset><legend>References</legend>
<p> Chu and Resnick, MRI Web Clinic June 2014.</p> </fieldset>