Purpose: During the second half of the 80s, Grammont, Trouilloud and Guichet developed a centromedullary nail for progressive limb lengthening. We analysed retrospectively twenty lengthenings, studying the clinical and radiological results to examine the quality of callus formation.

Material and methods: This study included eighteen patients, thirteen men and five women, who underwent lengthening procedures between 1991 and 2000. The patient’s clinical files were analysed in addition to the results of a physical examination. A standardised x-ray protocol was used to analyse bone regeneration.

Results: Mean follow-up was 4.55 years (1.5–10.5). Mean lengthening was 46 mm (30–80) achieved at a mean rate of 1.28 mm/d. The Bastiani index was 26 j/cm. Complications were: one progressive external popliteal sciatic palsy, one persistent knee flexion, one premature callus consolidation, and two callus fractures after nail removal. All patients maintained their activity level. The quality of regenerated bone was better in the dorsal and medial segments exposed to more stress. The callus was cortical and remodelled after removal of the nail.

Discussion: Like all lengthening techniques, the Albizzia nail requires careful preoperative planning, particularly to determine the level of the endomedullary osteotomy. The clinical results in this series were globally satisfactory. The callus was similar to cortical bone and quite different from the callus obtained with external lengthening methods, but our study demonstrated the excellent quality of the regenerated bone. The Albizzia nail can also be left in place until a solid reliable callus has formed, an advantage compared with external fixation which is less well tolerated.