On the plantar side of the metatarsophalangeal joint of the first toe, in the structure of the flexor apparatus there are two small bones smaller than a pea. Despite the fact that the bones are very small in size, they play a huge role during walking, running, jumping and other stress on the foot. If the sesamoid bones are involved in any pathological process, they become a source of severe pain, significantly worsening the patient’s quality of life.
Anatomy
At the base of the first toe is the first metatarsophalangeal joint, which is important from a functional point of view. Two small sesamoid bones are located on the plantar side of this joint: one is located on the inside, the other on the outside. The sesamoid bones are located inside the flexor tendons of the first finger. These structures together form the flexor apparatus of the first toe. Since the first finger bears heavy loads, these loads are performed due to the flexion apparatus. Sesamoid bones increase the leverage of the flexor tendons on the phalanges of the first finger, and also reduce the force of friction between the tendons and soft tissues in the position of extension of the first finger.
Causes
Pain syndrome can develop for various reasons. One of the reasons is overload of the ligamentous apparatus of the sesamoid bones. This condition may be called sesamoiditis. Overload most often develops after excessive running or dancing.
Another cause of pain associated with the sesamoid bones is fractures. Fractures can occur when landing directly on the first metatarsophalangeal joint of the foot. So-called stress fractures of the sesamoid bones may also occur. Stress fractures occur due to constant exposure to large loads on the sesamoid bone apparatus. This is typical for athletes; athletes are most often affected.
Another reason is arthrosis of the joint between the head of the first metatarsal bone and the sesamoid bones. When the big toe moves, the sesamoid bones slide anteriorly and posteriorly along the plantar surface of the head of the first metatarsal bone. Like other joints in the body, this joint can develop arthrosis. Arthrosis in this joint is typical for patients with a high longitudinal arch of the foot. With a high longitudinal arch of the foot, the apparatus of the sesamoid bones is under greater tension and the joints of the sesamoid bones are subject to greater load. Eventually, the cartilage of the sesamoids and the head of the first metatarsal begins to deteriorate.
A rare cause is a disruption of the blood supply to the sesamoid bones, resulting in disruption of the bone structure. This condition is called avascular necrosis of the sesamoid bone. In this case, calcium deposits may additionally form in the soft tissues around the first metatarsophalangeal joint.
Sometimes pain from the plantar surface comes from additional soft tissue formations under the big toe. For example, plantar keratosis can cause pain on the plantar aspect of the first metatarsophalangeal joint.
Symptoms of pathology
Often a person is unaware of the existence of such a phenomenon. The small bone does not show itself in any way and does not bother me. However, it usually grows out of sync with the true scaphoid bone, and over time this discrepancy can make itself felt. The situation can be aggravated by injuries with damage to the connecting bridge, regular increased loads on the lower limbs, as well as shoe pressure.
Symptoms may include increased sensitivity of the area where the accessory bone is located and pain coming from inside the foot. Sometimes these sensations make it difficult to stand on your toes. Athletes who need to wear special shoes, such as figure skaters and skiers, are especially susceptible to pain. Regular boots or shoes, if they are hard enough, can also cause pain.
Due to pathology, there may be problems with shoes.
In addition to the above, there are cases of swelling that extends to the arch of the foot. Sometimes calluses form on the surface.
Symptoms
Patients with pathology of the sesamoid bones usually feel aching pain from the plantar surface of the metatarsophalangeal joint of the first toe. When touched from the plantar side, the pain intensifies. Movement in the thumb joint is often limited. Patients notice that when walking, the pain intensifies before the foot pushes off for the next step. From time to time, the first metatarsophalangeal joint may become stuck or click, which increases pain. After rest, the pain goes away or weakens. Some patients report numbness in the area of the first and second toes.
Accessory scaphoid[edit | edit code]
Several ossification nuclei are involved in the formation of the scaphoid bone. Of all the bones of the foot, this bone is most often found to be split - in 20-25% of the population. The medial part, which has not merged with the main mass of the bone, forms a bony protrusion, sometimes causing pain. Symptoms appear during primary school age.
There are three types of accessory navicular bones.
- Type I is a small bone fragment in the area of the tibialis posterior tendon, sometimes called the external tibia.
- Type II is a larger fragment than in type I, connected to the scaphoid bone by a dense cartilaginous bridge.
- Type III is the formation of a medial projection on the scaphoid, which is an additional fragment fused with the main bone.
Diagnosis
The doctor will ask many questions about the development of the disease. You will be asked about your current complaints and past foot problems. The doctor will examine your feet. The examination may be a little painful, but it is necessary to identify painful points and check the movements of the fingers. The patient may be asked to walk around the room.
It is mandatory to take an x-ray (x-ray). Several projections are performed. One of them is the axial one, on which the sesamoid bones are clearly visible. This projection requires special placement and the X-ray beam comes at an angle.
An x-ray may reveal that the sesamoid bone is composed of two or more separate bones, as if it were a fracture, but the boundaries between them are smooth. This is normal and can occur in every tenth person. The x-ray evaluates the position of the sesamoid bones, as well as the space (articulation) between the metatarsal head and the sesamoid bones. The joint space normally appears uniform on x-ray. Narrowing and unevenness indicate pathology.
If it is difficult to judge the presence of a sesamoid fracture from a plain X-ray, a scan may be ordered. This is a test in which a special solution, a contrast agent, is injected intravenously. The contrast agent accumulates in the bone tissue in a certain way. By scanning the human skeleton with X-rays, special images are created that reflect the accumulated X-ray contrast agent. If there is a pathological focus in the bone tissue, then the pattern of accumulation of the contrast agent will look different. Each pathological process has its own unique pattern of contrast agent accumulation. In this way, a fracture can be distinguished from a congenital separation of the sesamoid bone.
To obtain the most complete picture of the disease, magnetic resonance imaging (MRI) may be necessary. Using MR images, you can study the relationships between the anatomical structures of the foot and exclude other pathological processes, including infection.
Treatment
Conservative treatment
As a rule, treatment begins with conservative methods. Typically, in this case, nonsteroidal anti-inflammatory drugs (NSAIDs), such as diclofenac, indomethacin, and ibuprofen, are recommended. These remedies usually relieve pain and inflammation well. You can try using special insoles that ease the load on the first metatarsophalangeal joint. Be sure to avoid using high-heeled shoes. The higher the heel, the greater the load on the forefoot, and therefore on the painful metatarsophalangeal joint. In some cases, your doctor may suggest injecting a steroid into the painful area. This usually helps relieve severe pain.
If there is a sesamoid fracture without a rupture of the extensor apparatus, wearing a plaster or plastic splint for approximately six weeks is recommended. After this, the patient must wear hard-soled shoes. The rigid sole holds the toe in a straight position, preventing the foot from rolling, thus relieving the load on the flexion apparatus. In some cases, the doctor may recommend treatment without the use of splints, prescribing the wearing of shoes with hard soles. If a fracture of the sesamoid bone occurs with a rupture of the flexor apparatus, then surgical treatment is necessary to fully restore function.
Stress fractures and aseptic necrosis of the sesamoid bone are less responsive to conservative treatment. Some doctors recommend a plaster or plastic splint for up to eight weeks without putting any weight on the leg. If after prescribing conservative treatment it does not get better within 8-12 weeks, then surgery is most likely necessary.
Stages and treatment of protruding foot bone
If for some reason the load is distributed incorrectly, then the arches weaken, the muscles supporting them cannot cope with the load, and the metatarsal bones begin to bulge towards each other.
As the load increases, the foot will become wider, and if you wear too narrow shoes, it will only aggravate the process of the appearance of a protruding bone, since the toe will constantly shift in relation to this bone and form an increasingly acute angle with it.
Stages of disease manifestation
The first stage of displacement is characterized by a slight displacement of the bone, only 20 degrees. In this case, the patient does not feel any unnecessary discomfort or pain, and visually the displacement is hardly noticeable.
At the second stage, the displacement reaches 30 degrees. If a person walks for a long time, painful sensations may occur in the foot, which disappear after a sufficiently long rest. Externally, the manifestation is quite noticeable, but does not affect the comfort of the shoes.
At the third stage, the displacement reaches 50 degrees, while the bone noticeably protrudes and interferes with normal walking. Pain occurs not only after long walks, but also during any walking. At this stage, they usually begin to select more comfortable shoes. Which is very difficult.
The final stage of the disease is characterized by a displacement of more than 50 degrees, the pain does not go away even with minor exertion, the bone is constantly inflamed, and even at rest it does not allow you to forget about itself. At this stage, the deformity may already affect other phalanges of the fingers, spreading to the entire foot.
How to properly treat protruding bones?
Many traditional doctors recommend all kinds of lotions for the feet, as well as baths, which should, in their opinion, restore the natural position of the protruding bone. However, they do not help and can only reduce pain if they contain the appropriate substances.
Minor deformities can be easily corrected using orthopedic devices and materials. For example, a night bandage helps a lot in the first stage. This is a plastic structure that fixes the foot in a certain position and moves it in the direction opposite to the direction of bone growth. The thumb is strictly fixed in the correct position and allows you to quite effectively solve the problem of a growing bone. The bandage is worn only at night, as it is difficult to walk with it on.
If one bandage is not enough for you, you can also use special pads that are placed on the inside of the shoe. They do not allow shoes to put pressure on the bone, causing pain. They also allow the thumb to be in the correct position.
At any stage, orthopedic insoles are recommended, which allow you to more competently distribute the load on the feet and spine, which in itself can save you from the progressive disease. These insoles need to be made to order so that they take into account the characteristics of your foot. They are made in literally half an hour, they are thin, so they easily fit into any shoes and allow you to feel comfortable and comfortable.
In addition to orthopedic methods, doctors can prescribe massage, exercise therapy, physiotherapy and other measures to prevent the worsening of foot deformities.
This will also relieve pain and return the bone to its previous state if treatment was started in a timely manner. Author: K.M.N., Academician of the Russian Academy of Medical Sciences M.A. Bobyr
Surgical treatment
Sesamoid bone removal
Your doctor may suggest removing part or all of the sesamoid bone. When the sesamoid bone is partially removed, the other sesamoid bone is able to provide a fulcrum for the flexors. However, if both bones are removed, the flexors will not be able to function normally and the first toe will become claw-shaped. Therefore, surgeons usually avoid removing both sesamoid bones.
When the sesamoid bone is fractured, surgery is performed to remove non-functional fragments and restore the integrity of the flexor apparatus. For stress fractures in athletes, when the most complete recovery is needed, surgery can be performed using bone grafts. To remove the sesamoid bones, an incision is made on the inside of the foot. Sometimes it becomes necessary to perform this operation from an incision along the plantar side of the foot between the heads of the first and second metatarsal bones.
Complaints and physical signs[edit | edit code]
Accessory navicular bone can cause redness, swelling and pain, and sometimes blisters and calluses on the protruding part of the foot. More often, these symptoms are observed in type II of the disease. The pain is especially common for skiers, figure skaters and hockey players, as they are forced to wear boots. Regular shoes can also cause pain if their inner edge is located in the projection of the scaphoid bone. The cause of symptoms is usually a fracture of the bridge connecting the accessory scaphoid to the main bone.
Rehabilitation
Rehabilitation after conservative treatment
If the pain syndrome is mild, the doctor may allow you to continue your daily activities immediately, but with the condition that you use shoes with hard soles. If the disease is moderate, you will need to use crutches and not put any weight on your leg for a period of several days to two to three weeks. If the pain is severe, you will need to walk on crutches without putting any weight on your leg for several weeks. Typically, full recovery should not be expected until four to six weeks.
Physical therapy can help reduce pain and swelling. If there are no contraindications, then ultrasound and thermal procedures are prescribed. Sometimes the use of anti-inflammatory ointments and creams is combined with physiotherapy.
Rehabilitation after surgical treatment
After surgery, most patients are advised to use crutches and avoid putting weight on the leg. For those who have undergone restoration of the flexor apparatus of the first toe or bone grafting, immobilization with a plaster or plastic splint is recommended. After this, it is recommended to wear shoes with hard soles until complete recovery. The results of bone grafting of the sesamoid bone can be assessed after 2 months by performing an MRI.
Physical therapy exercises are required. Depending on the operation performed, exercises begin at different times after the operation, gradually increasing the load and complexity. Therapeutic exercise is necessary to restore and maintain muscle tone of the lower leg and foot.
Treatment[edit | edit code]
Conservative treatment[edit | edit code]
In most cases, conservative treatment is quite effective. To reduce pressure on the affected area and relieve pain, orthopedic pads in the shape of a steering wheel are used. Sometimes it is enough to choose a different model of sports or casual shoes. Additionally, ski boots of even the same size can have different last shapes, with different boot volumes in the heel, midfoot, or forefoot. It is necessary to choose the most comfortable shoes for the patient and supplement them with orthopedic inserts. Boots for figure skaters and hockey players can also be adjusted using a special device - extruded in the area of the accessory bone.
Surgical treatment[edit | edit code]
Surgical intervention is indicated when conservative treatment fails. The accessory bone is excised. The previously popular Kidner operation is almost never used today.