The Ilizarov principle of distraction osteogenesis relies on which biological mechanism?

• A Periosteal stripping stimulates endochondral ossification at the distraction gap
• B Compression of a fracture site stimulates osteoclast resorption and callus formation
• C Tension-stress effect: slow distraction at 1 mm/day in 4 increments stimulates fibrous tissue transformation to bone ✓
• D Electrical stimulation through the wires promotes direct (membranous) bone formation

Explanation

Ilizarov's tension-stress effect: gradual distraction of living tissues at an optimal rate (1 mm/day in 4 increments of 0.25 mm) induces metabolically active regenerate bone (intramembranous ossification without a cartilage template) in the distraction gap between the corticotomy ends. Key prerequisites are: preservation of periosteum and medullary blood supply during low-energy corticotomy, 5-7 day latency period, 1 mm/day distraction rate, and stable fixation. Rates faster than 1 mm/day produce fibrous non-union; slower rates cause premature consolidation.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.