Large experimental segmental bone defects treated by bone transportation with monolateral external distractors

Area of Science:

• Orthopedic surgery
• Regenerative medicine
• Biomaterials science

Background:

• Large segmental bone defects (LSBD) present significant clinical challenges.
• Ilizarov's circular external fixators are established for bone reconstruction.
• Limitations of circular frames necessitate alternative fixation methods.

Purpose of the Study:

• To evaluate the efficacy of monolateral external fixators for bone transport in treating experimental LSBD.
• To compare monolateral frames with traditional circular devices for bone reconstruction.
• To assess the radiographic, computed tomographic, and histologic outcomes of bone transport using monolateral frames.

Main Methods:

• Monolateral external frames were applied to dogs and lambs with surgically induced femoral LSBD.
• Bone transport technique, adapted from Ilizarov's method, was employed for defect reconstruction.
• Radiographic, CT, and histologic analyses were conducted to evaluate bone healing and regeneration.

Main Results:

• Skin and soft tissues did not impede screw migration during bone transport.
• Satisfactory bone healing and remodeling of LSBD were observed in all subjects after four months.
• Histological examination revealed intramembranous ossification in the regenerated bone segments.
• Newly formed bone exhibited a normal diaphyseal appearance at the study's conclusion.

Conclusions:

• Monolateral external fixators are a viable and effective option for bone transport in treating LSBD.
• This technique minimizes drawbacks associated with circular fixation devices.
• Bone transport using monolateral frames results in satisfactory regeneration and restoration of diaphyseal bone structure.