The effect of tibial diaphyseal lengthening on the longitudinal growth of the tibia.

Limb lengthening by tibial callotasis is usually performed in the metaphysis but may cause growth inhibition. Is diaphyseal lengthening more advantageous? Sixteen immature rabbits underwent 30% diaphyseal lengthening by tibial callotasis. The tibial length was measured on radiographs at the end of the distraction period and after an additional 5 weeks. The proximal and distal growth plates were assessed histomorphometrically. Osteotomy stimulated tibial elongation; however, combined with diaphyseal lengthening the stimulation was suppressed resulting in longitudinal growth that matched the control side. In longer lengthenings of limbs diaphyseal callotasis may be more advantageous than metaphyseal by not inhibiting longitudinal growth.