Management of Bone Defects in Orthopedic Trauma - General Outlook

Introduction

Many clinical considerations, including the size of the defect, the patient's comorbidities, the health of the soft tissues, and the likelihood of infection in the fault, determine the treatment of traumatic bone defects. With the range of treatment approaches presented, it is crucial to pick a strategy to handle this challenging issue providing the best results.

Bone grafting is a primary therapy of choice for treating small-scale deformities. The induced membrane method and distraction osteogenesis are two primary choices taken into account for large-scale abnormalities. The related soft tissue damage, the local vascularity, and the potential for persistent infection should all be considered when picking one of the two procedures for treatment modality. For spontaneous bone repair to occur, vascularity is essential. Intervention to improve the healing potential is necessary when it has been impaired.

What Is the Use of Biological Materials in the Reconstruction of Bone Defects?

• Viable or non-viable bone material can be used to control biological reconstructions.

• Viable bone material was considered the gold standard for reconstructing post-traumatic bone defects from nonunion or malunion.

• Repair methods employing viable bone include the vascularized fibular graft, the vascularized iliac bone graft, bone lengthening with external fixation, and the induced-membrane approach.

• When a bone tumor has been removed, rebuilding using allograft, a biological reconstruction approach using non-viable bone, is performed.

• The benefits of both previously discussed procedures are incorporated into the repair using an allograft and a vascularized fibula.

• Moreover, the reuse of excised tumor bone can be categorized among reconstructive procedures that utilize non-viable bone material.

What Is the Use of Fibular Vascularized Graft in the Reconstruction of Bone Defects?

• Vascularized fibular grafts are frequently utilized with soft tissue defects to restore the bone defects caused by trauma larger than six cm caused by trauma, infection, or tumor removal.

• Single vascularized fibular graft, double-barrel method, and combined vascularized fibula and allograft repair are the three vascularized fibular graft choices that have been developed.

• A fibular graft up to 10 to 11 inches can be extracted from adult patients. The proximal fibula and the lateral malleolus should be left alone to maintain the stability of the knee and ankle joints, safeguard the common peroneal nerve, and maintain weight-bearing capability.

• If employed in the lower limbs, a traditional single vascularized fibular graft with a decreased cross-section may be susceptible to stress fractures.

• Techniques like the double-barrel method, the composite vascularized fibula, and allograft repair have been developed to avoid them.

• Upper extremity reconstruction, tibial defect, bone defect in pediatric patients, and generally all locations under lesser stress load indicate single vascularized fibular grafts.

• Because of its dual vascularization and sufficient blood supply, the fibular graft can be transversely osteotomized to form two parts when using the double-barrel approach.

• Deep soft tissue infection, pedicle thrombosis, stress fractures unrelated to fixation failure, compartment syndrome, and vascular damage are examples of serious consequences that have been documented.

• In a long-term follow-up of fibular grafts, it was found that 100 percent union rates are seen.

What Is the Use of Iliac Crest Bone Transplant in the Reconstruction of Bone Defects?

• Another often employed method to repair bone deficiencies brought on by infections, tumor removal, and fractures are iliac crest bone grafting.

• All the benefits of autografts, including osteogenesis, osteoinduction, osteoconduction, and histocompatibility, are present in iliac crest bone transplants.

• The anterior or posterior iliac crests may be used to harvest the bone transplant.

• To avoid iliac crest stress fracture, the anterior iliac crest is harvested no longer than 30 mm and around 1.5 to 2.5 inches posterior to the anterior superior iliac spine.

• The anterior iliac crest can be harvested using various methods, including the tricortical, segmental bicortical, trapdoor, iliac crest-splitting, trephine, and acetabular reamer procedures.

• To harvest the cortico-cancellous graft or pure cancellous graft, these techniques all reach the inner or outer table of the ileum.

What Are the Other Available Treatments for Bone Defects?

The magnitude of the defect will determine the type of therapy for treating bone defects, in addition to the lesion's location and surrounding vascularity.

• Small-scale critical flaws are those between four and six cm in length, whereas large-scale flaws are longer than that. Primary bone grafting is the recommended first therapy for abnormalities less than four and six cm. This will be covered in more detail and can be done using autograft or allograft methods.

• A critical-sized defect is a loss of bone that cannot mend on its own after surgical stabilization and needs further treatment and fixing.

• Distraction osteogenesis has been used to treat congenital musculoskeletal disorders, bone abnormalities after trauma and infections, and cancer surgery.

• After infection, tumor removal, and fractures, the induced-membrane approach, also known as the Masquelet procedure, is used to mend bone defects.

• After cancer surgery, recycling the bone segment that contains the tumor is an option to use allografts to treat bone abnormalities.

• The extracorporeal irradiated autograft procedure involves reimplanting a bone carrying a tumor after extracorporeal irradiation. After irradiation, ligaments, and tendons are saved for later use.

• Pasteurized autograft extracorporeal involves heating the bone carrying the tumor at a significantly higher temperature, killing the tumor cells without changing the graft's osteoinductivity or mechanical resistance. After extracorporeal pasteurization, the treated bone is moved to its original location and secured with plates and screws.

• To kill cancer cells, the freezing procedure employs liquid nitrogen. Cells dehydrate and create ice crystals as a result of the freezing process.

What Is the Management of Bone Defects Using Non-biological Materials for Reconstruction?

• An option for intercalary reconstructions is segmental prostheses. They provide quick recuperation, instant stabilization, and early weight bearing.

• Large bone abnormalities are still challenging to treat. There still needs to be an agreement on the best technique to use.

• This approach is preferable in patients with a low life expectancy due to myeloma, lymphoma, or metastatic bone cancer because of the significant risk of prosthetic and periprosthetic fracture.

• Hence, the ideal candidates for this treatment are elderly patients or patients with a short life expectancy, in whom the fast restoration of function and stability is more crucial than durability.

Conclusion

In treating orthopedic trauma patients, managing bone abnormalities brought on by trauma and nonunion continues to provide a significant therapeutic problem. There are many methods for treating bone abnormalities; however, it is difficult to draw firm conclusions due to a lack of quantitative data and insufficiently reliable information. Quantitative information on the rates of complications and reoperation must be provided by more research. The available evidence, current fracture care guidelines, and patient and surgeon considerations evaluation must all be considered when making treatment decisions.