Friday, April 18, 2014

Definition

The tibia is the second longest bone of the skeleton, located at the medial side of the leg. It articulates with the fibula laterally, the talus distally, and the femur proximally, forming part of the knee joint. It attaches to the ligament of the patella and to various muscles, including the popliteus and the flexor digitorum longus. It also is called the shin bone.

Description

The tibia is fractured more frequently than any other long bone. Fractures of the tibia and fibula can occur anywhere along the length of the bones. Fractures may be open (compound) or closed (simple), displaced or undisplaced, angulated or not angulated, stable or unstable.

Fractures of the tibia can be associated with acutecompartment syndrome. A closed fracture is a fracture in which the skin of the lower leg is not broken. An open fracture is classified according to the degree of skin disruption, and whether or not there is significant soft tissue loss, blood vessel disruption, or gross contamination.

Severe open fractures of the tibia have a high incidence of complications and a poor outcome. The most usual method of stabilization is by external fixation but the advent of small diameter locking intramedullary nails has introduced a new option.

Stress fracture of the tibia occurs in individuals who subject their extremities to repeated trauma. They can arise in otherwise healthy bone that is subjected to excessive loads (as in the marathon runner) or in abnormal bone that is subjected to minor loads (as in osteoporosis). These fractures may be anywhere along the tibial shaft and tend to be either transverse or oblique in orientation.

Fractures of the tibial spine or intercondylar eminence result from violent twisting, abduction-adduction injuries, or direct contact with the adjacent femoral condyle. Either the anterior tibial spine or, less commonly, the posterior tibial spine is affected, and rarely both are involved.

Boot-top Fractures And Skiing. You can break almost any bone of the body in a high-impact injury, but the bones most likely to break are the tibia and fibula in the leg - the so-called boot-top fracture. If the boot is rigidly fixed to the ski and the binding does not release, both bones will snap just above the boot-top if enough force is applied. This serious injury leaves the leg unstable because both bones are broken.

Breaking either the tibia or fibula is a traumatic injury that requires medical treatment. A fracture of the tibia is serious because this bone heals slowly and sometimes poorly because of the sparse blood supply in some areas of the bone. Often a surgical plate must be put in to stabilize the leg. Commonly seen among skiers, this fracture is called boot-top fracture since the leg breaks right at the top of the rigid ski boot.

Before the advent of rigid boots, skiers used to fracture their ankles. Now that their ankles are protected, they fracture the tibia. Two-thirds of all ski injuries occur in the lower limbs, and knee ligament injuries are the most common. The increase in knee injuries has been attributed to the modern, high ski boot with its forward-leaning position.

Knee injuries from skiing are usually due to severe torque to the knee when bindings fail to release the foot in a fall. When the foot is fixed to the ski, turning your body or the ski to a position the rest of the body cannot follow applies a severe rotary force to the knee. The damage can vary from a simple knee sprain to a tear of the medial collateral ligament (MCL), or cartilage, or even the anterior cruciate ligament (ACL). Out of an estimated 5 million people who ski each year, about 25,000 may get a third-degree knee sprain. This injury is no minor inconvenience. It requires surgery and/or long rehabilitation.

Treatment

Choice of treatment is dictated by local circumstances, the type of fracture and the facilities available.

A conservative regimen would involve plaster fixation. Other approaches are by operative reduction and rigid internal fixation. Methods of internal fixation include the use of screws, wires, and sutures. Treatments sometimes used are open reduction with pinning, closed reduction with hyperextension of the knee and fixation in plaster.

Some of the complications that may arise in treatment are:

  • A high incidence of open and infected fractures because the tibia lies superficially just beneath the skin
  • A tendency to displace the fragments when swelling subsides, particularly in oblique and spiral fractures
  • Cosmetic and sometimes functional disability if the alignment or rotational position of the fragment is imperfect
  • Conspicuous disfigurement if apposition of the fragments is imperfect
  • Slow union as a result of severity of the fracture, poor blood supply to one fragment, and sometimes distraction of the bone fragments
  • Occasional limitation of joint movement in the knee, ankle and foot, usually caused by associated joint, soft tissue, or vascular injury

Questions

Where is the fracture located on the tibia?

What treatment do you recommend?

Is surgery necessary?

Why does surgery need to be done?

Will internal fixation be required?

What are the risks and complications of surgery?