The implant you are most familiar with is not always the right one.
The implant you're most familiar with is not always the right one.
We've covered the mechanics all week. Today, the part that doesn't show up on X-ray: biology.
Fixation failure is not always a technical mistake. Sometimes it is a mismatch between construct stiffness and biological demand — and no imaging finding will tell you which one it is until the fracture has already stopped progressing.
Two failure modes.
One biological principle.
TOO RIGID
Atrophic Non-Union
Eliminates the micromotion that stimulates callus formation. Direct healing is only achievable if compression is geometrically perfect.
The fracture goes quiet — not because it is healing, but because it has stopped trying.
TOO FLEXIBLE
Hypertrophic / Fibrous Non-Union
Micromotion exceeds the threshold for bone regeneration. Malalignment, loss of reduction, and fibrous bridging replace bony consolidation.
The fracture moves too much to consolidate into solid bone.
Match the construct to the biology —
not the surgeon's habit.
The right construct sits in the biological sweet spot for that specific fracture, that specific patient, that specific soft-tissue envelope. No universal answer exists. Every decision is individual.
The Three-Line Rule
for implant selection.
When anatomic reduction and direct (primary) healing are the clinical priority — absolute stability, interfragmentary compression, no callus.
When fixed-angle support and biology preservation are needed — relative stability, callus-mediated healing, minimised periosteal stripping.
When load-sharing and minimally invasive fixation fit the fracture pattern — diaphyseal zones, soft-tissue compromise, polytrauma, poor biology.
Never let familiarity
substitute for individualised thinking.
Bone healing is biological before it is mechanical. Choose the construct that respects both dimensions — the mechanical demands of the fracture pattern and the biological capacity of that specific patient.
At Cargo Medi Distributors we provide orthopaedic implants that support individualised, evidence-based fixation decisions across South Africa — because the right implant starts with the right knowledge. 🦴
Supporting Every Fixation Decision
Across South Africa.
Full range. Every fracture pattern. Every clinical decision. Reach out to our team or follow us for weekly clinical insights.