broken metatarsal

Metatarsal breakage: description

The metatarsal fracture accounts for about one-third of all foot fractures, mostly athletes are affected. Most often, the fifth metatarsal bone is broken.

The metatarsals are systematically numbered from the inside to the outside (metatarsals I to V), with the first metatarsal joined to the big toe. The five metatarsal bones, together with the tarsal bones, form the arch of the foot. In particular, the outer metatarsals (I. and V. Metatarsalstrahl) are important for stability.

The first metatarsal is shorter, broader and more mobile than its neighbors. He wears about half the body weight under normal conditions. If the first metatarsus is broken, the force was usually so great that even surrounding soft tissues are damaged.

The middle metatarsals (metatarsals II to IV) are responsible in particular for the transmission of force during the course. At the fifth metatarsal bone the long fibular muscle (M. fibularis longus) starts. This serves to move the metatarsal bone in the direction of the sole surface of the foot. The fifth metatarsal bone is broken relatively frequently. Physicians call this metatarsal fracture Jones fracture, named after the surgeon Sir Robert Jones (1857-1933).

The Lisfranc joint forms the border between tarsus and metatarsus. It is part of the longitudinal and transverse arch of the foot and therefore exposed to considerable dynamic and static loads.

Metatarsal break: symptoms

Typical symptoms of metatarsal are midfoot pain. The exact pain location depends on the fracture type. In a Jones fracture, for example, more central pains occur in the area of ​​the lateral edge of the foot.

Because of the pain, the broken foot can hardly be stressed. He is also swollen in the midfoot region. Often a hematoma (bruise) occurs in the metatarsus, often reaching to the toes. Over the affected metatarsal bone is also a pressure pain felt. Sometimes the longitudinal arch is flattened, and when unrolling often occurs a bad load. If the ankle is broken, similar symptoms may occur.

For such symptoms, it is advisable to consult a doctor immediately – a metatarsal fracture is often detected too late and diagnosed only months after the injury. However, early diagnosis and treatment is important so that the foot can heal painlessly and no post-traumatic arthritis develops.

Metatarsal breakage: causes and risk factors

Cause is usually a direct impact of violence on the foot. A direct trauma, for example, is the result when a heavy object falls on the foot. Even a bruise can be responsible for a metatarsal fracture – for example, when a car drives over the foot.

Often a metatarsal fracture affects several metatarsal bones. In a simple metatarsal fracture usually the base of the fifth metatarsal bone is broken. The fragments move frequently, as the tendon of the long fibular muscle pulls the upper bone piece upwards. An isolated metatarsal fracture of the first metatarsal bone is rare as it is particularly stable.

There are different types of fractures in a metatarsal fracture:

Metatarsal break: stress fracture

Stress fractures (fatigue fractures) occur when the foot is injured or overstressed. Especially people with intensive physical activity such as aerobics, ballet, dancing or running are affected. The stress fracture usually affects the second to fifth metatarsal bones. It is also referred to as march fracture and happens especially runners who quickly increase their training load. The foot is repeatedly loaded on the outside.

Metatarsal break: head

The heads of the metatarsal bones are adjacent to the toes. If the middle-foot is broken in this area, a direct force is usually responsible for it. If the foot gets stuck somewhere or hits an object, the toe joint may also dislocate.

Metatarsal break: sub-capital

Cervical or subcapital fractures are often delayed. Cause is usually a lateral shear mechanism or an oblique direct force.

Metatarsal: shaft

If the shaft of a metatarsal bone is broken, it is often an oblique fracture. Accident mechanism may be a direct or indirect force or crush injuries.

Metatarsal break: base

The basic fracture usually arises as a result of direct force. It is often part of a Lisfranc dislocation fracture.

Metatarsal fracture V: avulsion fracture

The fifth metatarsal bone can cause a so-called avulsion fracture. It is usually the result of a Umknicktraumas (inversion trauma), as it pulls the tendon of the long fibular muscle at the fifth metatarsal bone, thereby triggering a fracture at the base. The avulsion fracture often occurs in younger patients (due to a sports injury) and older patients (due to falls).

Metatarsal V: Jones fracture

To distinguish from the avulsion fracture is the Jones fracture. It signifies a sudden rupture at the transition between metaphysis and diaphysis of the fifth metatarsal bone. This can happen, for example, when the foot is screwed in at the toe tip and bent over.

Lisfranc injury

The Lisfranc dislocation fracture is often a closed injury (no bone parts are visible from the outside) in victims of a car accident. It is caused by a direct impact of violence, in which the second metatarsal bone shifts backwards and tears the ligaments. Every fifth patient suffers several injuries.

Metatarsal failure: examinations and diagnosis

Accident victims usually carry several different injuries, which is why they often overlook a metatarsal fracture. The foot injury is sometimes discovered only years after the accident. That’s why you should visit a doctor for orthopedics and trauma surgery at the slightest suspicion of a metatarsal fracture.

To diagnose a metatarsal failure, the doctor will ask for the exact location of the accident and your medical history and then conduct a clinical examination. Some questions from the doctor might be:

• What does the exact accident happen?
• Do you have pain?
• Do the pain occur during exercise?
• Did you have any complaints like pain or restricted mobility before?

Immediately after the accident, a metatarsal fracture can be determined by the significant malposition. However, at a later date, the often massive swelling may make the diagnosis more difficult. In particular, the soft tissues surrounding the foot as well as nerve and tendon damage must be carefully recorded.

Metatarsal break: Imaging procedures

Imaging techniques are used for a safe diagnosis. In any case, this includes an X-ray examination, where images are taken in three levels: from the dorsum to the sole of the foot (dorsoplantar), strictly lateral and oblique views with raised Fußaußenrand. If the radiographs are not meaningful enough, the doctor will additionally order a magnetic resonance tomography (MRI) and / or a computed tomography (CT).

In the case of a fatigue fracture, the diagnosis is often initially difficult because no fracture gap is visible. Only later, when the bone reacts to the fracture and forms a callus (consisting of newly formed bone tissue), the fracture can be localized. With the help of an additional MRI image of the foot, a previous diagnosis is better possible.

In addition, an MRI, scintigraphy (nuclear medicine examination) or angiography (vascular X-ray) is performed if the metatarsal fracture is due to illness. This is the case, for example, with a fatigue fracture, diabetic neuropathic osteoarthropathy (DNOAP) or bone tumors.

Metatarsal break: treatment

If the metatarsus is broken, there is no need for surgery. Only with a very delayed fracture is an operation recommended. The treatment goal is that the foot is painless and fully resilient again.

Conservative metatarsal treatment

For a non-displaced or slightly shifted foot fracture, which is not shortened, can be treated conservatively. This requires that the affected person does not move and relieve his foot for a long time, otherwise the risk of a new fracture or osteoarthritis is high. For this purpose, the foot is first stabilized from the outside with hard soles, soft cast (a support bandage) and tape assemblies. The plaster has to be worn for about six weeks. Depending on the fracture type, the foot can be loaded after about four weeks. The foot is then checked regularly with the help of the X-ray examination.

A metatarsal fracture V (avulsion fracture) does not require surgery. It is enough if the person concerned wears a so-called stable shoe or a firm shoe sole to protect the foot.

If the fracture is minimally shifted in a Jones fracture, the foot can first be immobilized in a plaster shoe for six weeks. The patient may load the foot fully, as the plaster shoe is very stable and the upper ankle joint remains free to move. Thereafter, the foot can be provided with fixing bandages until it has regained its functionality.

Most stress fractures can be treated conservatively. The foot should be rested in the plaster shoe for about six weeks.

Surgical metatarsal treatment

If the foot is broken and the fracture fragments are displaced, surgery is required to reorient and stabilize the bone fragments. The patient is operated on a supine or lateral position, and the fracture screwed or flattened. This usually only requires two days hospitalization. Regular X-ray checks determine when the foot can be increased again.

Is the metatarsal fracture at one Jones fracture shifted by more than five millimeters, it is supplied with a lag screw or a tension belt. This operation is recommended especially for athletes. After the operation, a firm sole should be worn in the shoe.

At a Fracture of the remaining metatarsals The bone is closed again aligned and fixed under the skin with so-called spiked wires (Kirschner wires). If the bone fragments can not be aligned, it must be operated open. Because the first metatarsal stabilizes the foot, it has to be fixed very early and well.

Lisfranc injury

In a fracture of the Lisfranc, the fracture must be reoriented openly. The breakage is usually at the base of the second metatarsal, which is first corrected. To keep it that way, two spiked wires are inserted from the side. The bases of the metatarsal bones are provided with screws on the tarsal bone row.

If there is severe soft tissue damage, it is treated with a so-called “external fixator”. The Schanz screws are inserted into the first and fourth metatarsal bones and into the tibial shaft.

Metatarsal break: disease course and prognosis

The healing process can be quite different in a metatarsal fracture. Duration and course depend on the type of breakage. An important role also plays, whether soft tissues were damaged. The prognosis for an isolated metatarsal fracture of the shaft of the first and fifth metatarsal bone is good – provided the fragments have been anatomically correctly aligned. If complications persist, it usually takes about eight weeks for the bone to heal completely.

Metatarsal: complications

In a debris fracture or when multiple metatarsal bones are broken, which could not be properly aligned, a post-traumatic sprawl and flatfoot can form.

If cartilage has been damaged in the metatarsal fracture, arthrosis may develop despite good treatment. If there is a Jones fracture, occasionally pseudarthrosis can occur, that is, the bone fragments do not grow together completely. In open fractures may be a complication osteitis (bone inflammation) arise. Does that go? broken metatarsal associated with crush injuries, there is also the risk of a compartment syndrome.