Attempted limb lengthenings beyond twenty percent of the initial bone length: Results and complications

In response to historic guidelines suggesting limits to the amount of limb lengthening, we report the results and complications of those patients in w hom the initial goal of lengthening exceeded 20% of the initial segment len gth. Thirty-one patients underwent a total of 35 attempted lengthenings wit h a mean follow-up of 38.6 months. Limb-length discrepancy was the primary indication in all but one case. With an average goal of 35% of the original bone length, we achieved a mean gain of 33%. Lengthening to within 2.5 cm was achieved in 31 (89%) of 35 cases, and significantly more successful wit h goals extending less than or equal to 55% of the initial bone length (p < 0.05). Treatment times extended a mean of 8.7 months with a healing index of 37 days/cm. By Palsy's classification scheme, all had problems, in addit ion to an average of 1.3 obstacles and 0.9 complications per segment length ened. In 23 patients with extended follow-up, good to excellent results wer e achieved in 78%, and were significantly more successful with goals less t han or equal to 55% (less than or equal to 0.05).