Ilizarov, Clin Orthop Relat Res 1989 - The Tension-Stress Effect on the Genesis and Growth of Tissues. Part I. The Influence of Stability of Fixation and Soft-Tissue Preservation
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The Tension-Stress Effect on the Genesis and Growth of Tissues. Part I. The Influence of Stability of Fixation and Soft-Tissue Preservation
Ilizarov tested how fixator stability, preservation of marrow and periosseous soft tissue, and the direction of distraction affect new bone formation in the canine tibia.
Experimental canine tibia study in three series using the Ilizarov circular fixator: lengthening, lateral widening and cortical defects.
Methods
Model
Adult dog tibia
Transfixion‑wire Ilizarov circular fixator
Intervention
Longitudinal lengthening in 5 groups varying fixation stability and marrow preservation (480 dogs)
Lateral widening in 2 groups varying marrow preservation at 3 distraction rates (38 dogs)
Half- vs full‑circumference cortical defects with or without marrow isolation (38 dogs)
Assays
Histology of the distraction zone
Ultrastructure of muscle, nerve, skin and vessels
Time points
Findings reported at days 7, 14 and 21
Key Findings
More stable fixation and maximal preservation of periosteum, marrow and medullary blood supply each improved bone formation during lengthening.
The type of regenerate followed fixation stability: loose fixation gave fibrous tissue with cartilage islands, intermediate fixation gave fibrocartilage, and rigid four‑ring fixation gave direct osteogenesis by day 14.
Closed osteoclasis, the group with the most complete marrow and periosteal preservation, united prematurely at 0.5 mm/day, so these limbs were distracted at 1.5 mm/day in four increments.
Lateral widening opened a 20 to 22 mm gap that was filled by day 14 with transversely oriented osteoid and trabeculae.
With intact marrow and nutrient vessels, a full‑circumference cortical defect filled with relatively dense bone by day 21, and new bone still formed quickly when a polyvinyl chloride sheet isolated the marrow from periosseous tissue.
Skin under distraction thickened, with up to 10 basal cell layers vs 3 to 5 in control limbs.
Board pearl
In Ilizarov's widening experiments, regenerate bone lined up with the tension vector even when that vector ran perpendicular to the limb's long axis.
Authors' conclusion
New bone formed rapidly, even when the marrow was separated from the surrounding periosseous soft tissues by a sheet of polyvinyl chloride, attesting to the importance of marrow element preservation during osteotomy for limb lengthening.
Ilizarov tested how fixator stability, preservation of marrow and periosseous soft tissue, and the direction of distraction affect new bone formation in the canine tibia.
Experimental canine tibia study in three series using the Ilizarov circular fixator: lengthening, lateral widening and cortical defects.
Methods
Model
Adult dog tibia
Transfixion‑wire Ilizarov circular fixator
Intervention
Longitudinal lengthening in 5 groups varying fixation stability and marrow preservation (480 dogs)
Lateral widening in 2 groups varying marrow preservation at 3 distraction rates (38 dogs)
Half- vs full‑circumference cortical defects with or without marrow isolation (38 dogs)
Assays
Histology of the distraction zone
Ultrastructure of muscle, nerve, skin and vessels
Time points
Findings reported at days 7, 14 and 21
Key Findings
More stable fixation and maximal preservation of periosteum, marrow and medullary blood supply each improved bone formation during lengthening.
The type of regenerate followed fixation stability: loose fixation gave fibrous tissue with cartilage islands, intermediate fixation gave fibrocartilage, and rigid four‑ring fixation gave direct osteogenesis by day 14.
Closed osteoclasis, the group with the most complete marrow and periosteal preservation, united prematurely at 0.5 mm/day, so these limbs were distracted at 1.5 mm/day in four increments.
Lateral widening opened a 20 to 22 mm gap that was filled by day 14 with transversely oriented osteoid and trabeculae.
With intact marrow and nutrient vessels, a full‑circumference cortical defect filled with relatively dense bone by day 21, and new bone still formed quickly when a polyvinyl chloride sheet isolated the marrow from periosseous tissue.
Skin under distraction thickened, with up to 10 basal cell layers vs 3 to 5 in control limbs.
Board pearl
In Ilizarov's widening experiments, regenerate bone lined up with the tension vector even when that vector ran perpendicular to the limb's long axis.
Authors' conclusion
New bone formed rapidly, even when the marrow was separated from the surrounding periosseous soft tissues by a sheet of polyvinyl chloride, attesting to the importance of marrow element preservation during osteotomy for limb lengthening.