Displaced Sesamoid Bone
By Kerri Gilbert, PT, DPT
What is a Sesamoid Bone?
A Sesamoid Bone is a bone that is encapsulated within a tendon or joint capsule. They are near a joint or area of tendon attachments. Their function is to modify pressure, reduce friction, and sometimes alter the direction of muscle pull. The largest and most commonly known sesamoid bone is the patella or the knee cap. This bone is within the quadriceps tendon, the major extensor tendon of the knee joint.
More common sesamoid bones include the ones found underneath the great toe near the foot’s ball. These sesamoids are in the shape of two small peas and act as a pulley system for the great toe, creating leverage for walking and running activities.
Common Injuries to the Sesamoid Bones of the Foot
- Sesamoiditis: Categorized as an overuse injury creating inflammation of the sesamoid bones and tendons of the great toe, specifically the flexor hallucis longus muscle metatarsophalangeal joint. Common symptoms include a dull, intermittent pain under the great toe often changed with shoe wear and modifications to activities.
- Fracture: Categorized as acute fracture, break, or chronic fracture.
- Acute Fracture: Caused by a trauma to the bone. Symptoms are immediate pain and swelling in the area of the fracture. This is common in dancers, basketball players, volleyball players, and other sports involving high-impact loads through the feet. These injuries are likely to cause a displaced sesamoid bone, which requires surgical repair if conservative treatments fail. More on that later.
- Chronic Fracture: Also known as a stress fracture, is caused by repetitive stresses through the sesamoid bone area. The symptoms are generally intermittent, worse with activities, and ease with rest. Early diagnosis and conservative treatment lead to the best outcomes for people with this injury.
- Turf Toe: Categorized as soft tissue injury surrounding the great toe. This normally occurs when the great toe extends past the normal range of motion. Sometimes an athlete will hear a pop during the injury, causing immediate sharp pain and limiting a great toe range of motion. This injury can also cause displaced sesamoid bones that lay underneath the great toe.
How to Treat a Displaced Sesamoid Bone?
There are several ways to treat a displaced sesamoid bone. You should always consult a medical professional if you feel you have injured yourself.
- Immobilization: Place foot in cast or walking boot, using crutches to offset body weight.
- Padding, strapping, or taping: padding in shoes to comfort inflamed sesamoid bone. Strapping and taping are utilized for correcting the alignment of the great toe and/or relieving the area of tension when the sesamoid is displaced.
- Steroid injections: to reduce inflammation and cause pain around a joint.
- Physical Therapy: Conservative treatment should always be tried first when it comes to sesamoid injuries and a displaced sesamoid bone. Physical therapy treatment can help you regain range of motion, improve strength, enhance balance and proprioception awareness, and utilize modalities when appropriate. PT’s (physical therapists) have specialized skills, including manual therapy techniques and knowledge of appropriate movement patterns to return athletes and active adults to desired activities and sports with a reduced risk of injury.
- Surgery: When conservative treatment fails, surgery may be required. Contact a foot and ankle orthopedic surgeon for evaluation and more information.