Intramedullary nail osteosynthesis is a surgical procedure used to treat long bone fractures. In this method, the surgeon inserts an intramedullary nail into the medullary canal of the bone.
What is intramedullary nail osteosynthesis?
Intramedullary nail osteosynthesis is a surgical procedure used to treat long bone fractures. In this method, the surgeon inserts an intramedullary nail into the medullary cavity of the bone. Intramedullary nail osteosynthesis is also known as intramedullary nailing. This refers to a surgical method in which an elongated pin made of metal, like a bone nail or intramedullary nail, is inserted into the marrow of the damaged bone. In this way, the restoration of a fractured long bone takes place by promoting the formation of callus and thus the healing of the bone. Tubular bones such as the femur were fixed in an intramedullary manner from 1887 onwards. In 1916, some physicians also resorted to bones from cattle or ivory. In 1925 the three-lamellar nail was introduced, which was used for fractures of the femoral neck. In 1940, the German surgeon Gerhard Küntscher (1900-1972), who is considered to be the inventor of intramedullary nailing, provoked heated controversy when he presented his intramedullary nail at a conference of the German Society for Surgery. At the time, bone marrow was considered inviolable and irreplaceable for bone vitality. Over the years, however, intramedullary nail osteosynthesis has achieved convincing therapeutic success. The intramedullary nail allowed the injured limb to be loaded again more quickly, which shortened the patient’s stay in hospital. The patient’s ability to work could also be restored more quickly. In contrast, the other treatment methods involved numerous complications, which were now avoided with intramedullary nail osteosynthesis. The 1950s saw the introduction of reamed intramedullary nailing, which became the standard method of treating tibial shaft fractures. Although it is not necessary from a medical point of view, the intramedullary nail is removed once the fracture has healed. Thus, its locking screws can be troublesome.
Function, effect and goals
In modern times, intramedullary nails made of inert titanium are used. With the help of these implants, static or dynamic locking and compression on the gap of the fracture can be achieved. Indications for intramedullary nail osteosynthesis are open or closed fractures of large long bones such as the tibia, femur and humerus. Intramedullary nail osteosynthesis is also useful for special treatments. For this purpose, various special implants are available that have special properties. The most common applications of intramedullary nail osteosynthesis are short oblique fractures or transverse fractures such as those of the thigh. The first step of the procedure is bone reduction. In this process, the surgeon returns bone fragments that have shifted to their original position. Depending on how long the fracture is, the surgeon inserts the intramedullary nail through a small skin incision from the end of the bone to the inside of the bone. In intramedullary nail osteosynthesis, a distinction is made between two different procedures. These are the undrilled and the reamed intramedullary nail. If a reamed intramedullary nail is used, the surgeon first reams the medullary canal of the bone. The next step is to drive an elongated hollow nail into the medullary cavity. If, on the other hand, an undrilled intramedullary nail is used, reaming of the medullary canal is not necessary. In addition, the surgeon uses a solid nail that is thinner. The undrilled intramedullary nail is used to treat severe open fractures. By using an undrilled nail, the blood vessels located in the bone marrow can be spared. New bone substance is produced through the medullary cavity and the bone is supplied with blood. If an injury to the medullary canal occurs due to a reamed nail, this is often disadvantageous for the healing process. There are also differences between the types of intramedullary nails in terms of locking. For example, a locking screw is absolutely necessary for an undrilled nail, while the locking of the reamed nail is optional. Locking refers to the fixation of the intramedullary nail to a bone end with bolts or screws. Physicians differentiate between static and dynamic locking.During static locking, the intramedullary nail is fixed at both ends, which ensures a stable connection. This prevents the bone fragments from giving way. In the case of dynamic locking, the nail is only attached to the end of the bone near the fracture. The connection is therefore less rigid. The surgeon decides which type of nail is ultimately more suitable based on the extent, shape and position of the fracture.
Risks, side effects and hazards
Despite its many benefits, intramedullary nail osteosynthesis can also cause some complications. These primarily include pseudarthrosis and malpositioning. Pseudarthrosis is when the bone fails to heal after a surgical procedure. It is also called pseudo joint or false joint. The bones affected by pseudarthrosis are mostly the upper and lower leg bones. The complication becomes noticeable through chronic pain and constant functional limitations. In addition, the mobility of the affected limb is considered abnormal. Treatment usually requires further osteosynthesis. Another common complication of intramedullary nail osteosynthesis is primary or secondary malalignment. For example, both reamed and undrilled intramedullary nails can result in external rotational malalignments. The reason for this is usually incorrect execution of the intramedullary nail osteosynthesis by the surgeon. In rare cases, a pin fracture can also cause primary malalignment. Other possible complications include fat embolism, infection, or implant failure. The risk of infection is particularly high in open fractures. Implant failure is said to occur when a pin fracture or fracture of the intramedullary nail occurs.
Typical and common bone diseases
- Osteoporosis
- Bone pain
- Bone fracture
- Paget’s disease
