Dorset Foot & Ankle Clinic

Figure 1 – 3D reconstructed sesamoiditis This is a 3-dimensional reconstruction CT scan of a fragmented lateral sesamoid

Figure 2 – The lateral sesamoid can be seen to be fragmented

Sesamoid Pain

Sesamoid bones are two small bones that lie underneath the big toe joint. There are two of them; medial and lateral. They are like little kneecaps beneath the big toe and help transfer weight from the body to the floor. In ancient times these bones were of great interest and were thought to hold great mystical powers.

There are three principal problems that can occur with the sesamoids.

1. Sesamoid fractures

Sesamoid fractures can occur acutely with a sudden sporting type injury or can be a chronic stress injury, again often caused by sport. Some people with a painful sesamoid are discovered to have a sesamoid in two parts called a bipartite sesamoid. It is sometimes not clear whether this has been an old injury or whether the person has grown with a double sesamoid.

Resolution of symptoms from these sesamoids can be achieved by simply resting the foot or using a stiff soled insole in the shoe. In some cases where pain fails to resolve, it is sometimes possible to fix the two fragments together with a tiny screw, or failing this removal of the smaller of the two fragments will often relieve the pain.

2. Sesamoiditis

Inflammation of the sesamoid bone can occur, again particularly with sporting activities. As with a stress fracture treatment with stiff insoles to rest the joint can be effective. In rarer cases the sesamoid may need to be removed to resolve symptoms.

3. Sesamoid Arthritis

The sesamoids form a joint with the metatarsal head above. This joint can become arthritic, either as an isolated problem or in conjunction with arthritis of the big toe joint. If conservative treatments such as steroid injections or insoles fail to relieve symptoms, then again removal of the sesamoid can be performed.

Removal of the sesamoid is not an operation undertaken lightly. Its complications include failure to relieve the pain, appearance of deformity of the toe joint and recurrence of the pain at a later date. These can be very difficult to treat.