Goodship and Kenwright tested whether controlled daily axial micromovement improves tibial fracture healing compared to rigid fixation. Using a sheep tibial osteotomy model over 12 weeks, they assessed healing with serial radiographs, in vivo stiffness testing, post-mortem torsional testing, and histology. The loading parameters were chosen to match regimes already proven osteogenic in intact bone.
Rigid fixation was long assumed to be the gold standard for fracture healing — more stability meant better outcomes. This paper was among the first to quantify why that assumption is incomplete.
When you plan fixation for a high-risk tibial diaphyseal fracture, the mechanical environment you create matters as much as the stability you achieve. A completely rigid construct suppresses external callus and, in this model, cut torsional stiffness recovery nearly in half compared to controlled micromovement.
This is the mechanobiological rationale behind fixation strategies that permit axial micromovement: dynamized external fixators, intramedullary nail dynamization, and functional bracing all exploit this principle. The fracture environment with controlled axial loading promotes external bridging callus. A faster, more robust healing pathway.
The key limitation for boards: this was a clean surgical osteotomy in sheep, not a comminuted shaft fracture with soft tissue stripping. Optimal parameters in humans remain to be defined. Goodship's 1993 follow-up work on fixator frame stiffness extended these findings toward clinical application.
Goodship and Kenwright tested whether controlled daily axial micromovement improves tibial fracture healing compared to rigid fixation. Using a sheep tibial osteotomy model over 12 weeks, they assessed healing with serial radiographs, in vivo stiffness testing, post-mortem torsional testing, and histology. The loading parameters were chosen to match regimes already proven osteogenic in intact bone.
Rigid fixation was long assumed to be the gold standard for fracture healing — more stability meant better outcomes. This paper was among the first to quantify why that assumption is incomplete.
When you plan fixation for a high-risk tibial diaphyseal fracture, the mechanical environment you create matters as much as the stability you achieve. A completely rigid construct suppresses external callus and, in this model, cut torsional stiffness recovery nearly in half compared to controlled micromovement.
This is the mechanobiological rationale behind fixation strategies that permit axial micromovement: dynamized external fixators, intramedullary nail dynamization, and functional bracing all exploit this principle. The fracture environment with controlled axial loading promotes external bridging callus. A faster, more robust healing pathway.
The key limitation for boards: this was a clean surgical osteotomy in sheep, not a comminuted shaft fracture with soft tissue stripping. Optimal parameters in humans remain to be defined. Goodship's 1993 follow-up work on fixator frame stiffness extended these findings toward clinical application.