Clinical Presentation
Sesamoiditis is characterized by pain on the sole of the foot at the base of the great toe (Figure 1). Sesamoiditis is a general term for symptoms associated with one or both of the seasmoids bones located under the base of the great toe. Symptoms can orginate from a variety of causes most of which are related to excessive loading to this area of the foot (Figure 2). Patients will often describe a recent increase in repetitive weight-bearing activities (ex. increasing their running training). Pain from this area often leads to a restriction of activities and possibly even a limp. Patients will often find it uncomfortable to walk with barefeet, particularly on hard surfaces
Physical Examination
Tenderness is located around one or both of the sesamoids (base of the big toe) on the sole of the foot. It is common for sesamoiditis to be associated with a high arched foot as this type of foot tends to concentrate loading over the base of the great toe (Figure 2). Often motion of the great toe is normal, although there may be pain at the extremes of motion, particularly when the toe is flexed upwards (Figure 3). Marked loss of motion of the big toe and pain on the top of the great toe is more consistent with a diagnosis of hallux rigidus.
The actual symptoms can stem from a variety of causes including: local overload of the soft-tissues in this area with resulting chronic tissue injury; stress fracturing of one of the sesamoids; and cartilage damage (arthritis) between the sesamoid and the first metatarsal head. An acute injury to the great toe can produce pain in this area although if an acute injury has occurred a diagnosis of a “turf toe” is more likely. A turf toe is an injury to the joint capsule (ligaments) at the base of the great toe.
Imaging
Plain x-rays of the foot will allow the main joint of the great toe (the 1st metatarsophalangeal joint) and the sesamoids to be assessed. Fractures of the sesamoid can usually be diagnosed on plain x-rays although they may need to be differentiated form a bipartite sesamoid (a sesamoid that has two parts joined by fibrous tissue). Bipartite sesamoids are common and are usually asymptomatic.
An MRI may need to be ordered in order to assess whether there is evidence of joint damage (ex. arthritis) in the great toe, a capsule injury (turf toe); or a stress fracture of one of the sesamoids.
Treatment
Treatment of sesamoiditis first requires ensuring that the symptoms are not caused by a fracture of the sesamoid or by an injury to the joint capsule of the great toe (turf toe) as these conditions may be treated differently. If as is commonly the case the symptoms are from overload to the base of the great toe the condition is treated by off-loading the area, modifying activities in the short-term to decrease repetitive injury to the area, and possible taking medications to improve symptoms. Specific Treatments include:
- Activity modification: Symptoms are often precipitated by an increase in activity level, a change in shoewear, or a change in activities – anything that serves to increase the force or loading and the repetition of loading to that area of the foot. Stopping any precipitating activity is a key first step to managing the symptoms of sesamoiditis. Decreasing activity level or modifying activities to dramatically decrease the loading to this area of the foot is an important short-term step to allow the chronically injured tissue in the foot to have a chance to heal. After symptoms have settled and other treatments have been instituted activity level can be gradually increased.
- Off-loading shoe inserts: A shoe insert designed to cushion and offload the area under the base of the great toe can be very helpful. This can be done by either using a cushioning insert and adding a “Dancer’s pad” to take load away from the involved area, or by using an orthotic with a recessed area under the base of the great to so that this area is taking less force with each step than it normally does.
- Comfort shoe wear: Shoes that disperse forces evenly away from the front of the foot can be helpful. Typically shoes with a stiff sole and a slight rolling curve to the sole (rocker-bottom contour) will be helpful. It is important to combine a stiff sole with a soft or contoured insert/orthotic as the use of a stiff sole by itself may aggravate symptoms.
- Anti-Inflammatory Medications (NSAIDs): In patients who do not have any contra-indications the use of anti-inflammatory medications may help provide excellent short-term pain relief. It is important to realize that NSAIDs address the pain response, but often do not address the underlying reason leading to the pain (repetitive localized loading)
Edited July 1st, 2010
