Simultaneous Limb Lengthening With Ankle Fusion Using an Internal Lengthening Nail

We reviewed 18 limbs in 17 patients who underwent ankle fusion with simultaneous tibial lengthening with a magnetic internal lengthening nail. All patients had preoperative limb length discrepancy (LLD) (mean 4.9 cm (2.6-7.6 cm)) with ankle deformity. The ankle was fused from medial or lateral approaches using screws/plate constructs placed adjacent to the retrograde Precise nail. Lengthening was carried out by a distal 1/3 tibial osteotomy. Clinical and radiographic measures were performed after a mean follow-up of 20 months (12-37 months). The mean amount of lengthening performed was 4 cm (1.8-7.2 cm). The final mean LLD was 1 cm (0.7-1.1 cm), which was statistically significant (p<0.01) as compared to preoperative. The foot was plantigrade in all cases. The mean foot rotation was 10° (5-15°) external, relative to the knee. At final follow-up all patients reported minimal to no pain, and all claimed to be walking more functionally than before surgery. Ankle fusion and limb lengthening was achieved in all cases. Combining both treatments by using an internal lengthening nail was very effective and avoided leaving patients with a dysfunctional LLD or of having a separate limb lengthening procedure. This is the first report of such a combined treatment of ankle fusion with internal tibial lengthening nail.