Bone defect is a term which refers to the absence of a part of the bone. Very small bone gaps can be expected to heal with the normal bone-healing ability of the human body. In order to better organize our thoughts we have developed the concept of critical sized bone defect, which is defined as a defect which is too wide to heal spontaneously or, more practically, wider than 2.5 times the diameter of the bone on that particular level. Critical sized bone defects require special reconstructive procedures to heal.
Bone defects most often occur after severe open fractures, bone infections and, less commonly, after bone tumors.
In such conditions, the first goal of treatment is to surgically remove the dead or affected section of bone and soft tissues (muscles, tendons, vessels and skin) to clear the body from the diseased tissue. This procedure is called “Debridement”. Depending on the extent and the nature of the underlying disease the extent of debridement may vary.
This leaves a bone defect of variable length which needs to fill with new bone in order to provide good function to the limb. After the clearing of the diseased tissues has been achieved, the second goal of treatment is to restore the function of the limb as closely to normal as possible.
This requires mechanical stability (that is a strong and well-aligned bone to support the body) and well- functioning soft tissues (muscles, tendons, vessels and skin). This is achieved by applying special methods for filling the bone defect with newly formed bone. The available methods are:
- Bone transport (or Distraction osteogenesis)
- Induced membrane technique
- Free vascularized fibular graft.
At the same time with the bone reconstructive procedure, special plastics reconstructive procedures are undertaken by the plastics surgeons to address the soft tissue problems. All these bone and soft tissue procedures are complex, require special experience and training and may be performed in multiple stages. It should be understood that such diseases and their related treatments pose a challenge for the patients and their families alike.