Leg Lengthening With a Motorized Nail in Adolescents

Abstract

Leg lengthening by external fixation is associated with various difficulties. We evaluated eight adolescent patients who underwent leg lengthening with a motorized intramedullary lengthening device. We asked whether this method could reduce the time of hospitalization and rehabilitation and whether the incidence of complications commonly associated with external fixators could be reduced. We compared our preliminary results with those from other reports, with a focus on leg length achieved, time of rehabilitation, and rate of complications. The average leg-length discrepancy was 3.8 cm (range, 3-5 cm). The average lengthening distance was 3.8 cm (range, 2.9-4.7 cm). In six patients, leg lengthening was combined with successful correction of the mechanical axis alignment. The consolidation index averaged 26 days/cm (range, 19-41 days/cm). The average hospital stay was 9.6 days. No bone or soft tissue infections were observed. In comparison to other studies (1.0-2.8 complications/ patient), our results suggest that the difficulties commonly associated with external fixators can be reduced with this method. It also allows good angular correction in patients with mechanical axis deviation. These features combined with a short time of hospitalization and rehabilitation make it a promising procedure for limb lengthening.

Intramedullary Skeletal Kinetic Distractor in the Treatment of Leg Length Discrepancy—A Review of 16 Cases and Analysis of Complications

“…[1][2][3][4][5][6][7][8][9][10][11] Fully implantable IM systems have the advantages of greater comfort, better acceptance by patients, earlier rehabilitation, and reduced risk of infection and deformity. 12,[14][15][16][17][18][19] Furthermore, there is a diminished risk of late complications as the nail provides long-term stability to the lengthened bone compared with the traditional Ilizarov method where a significant risk of gradual late deformity or fracture exists. 8,9 Several fully implantable devices have been developed over the years.…”

“…14 Fitbone, an implantable motorized lengthening nail, has recently shown promising results and demonstrated good control of the distraction rate. [15][16][17] However, the device is subject to implant failure caused by broken wires or motor dysfunction. Such complications have been reported in 2 of 11 patients, 15 2 of 10 patients, 16 and 2 of 8 patients 17 in various series.…”

“…Up to 25% of patients never achieved their full desired distraction lengths. 16,17 Recently, several authors have reported their experience with the use of the ISKD (Table 5). [18][19][20][21][22] Results have been consistent in achieving desired distraction lengths for nearly all patients; however, complications requiring return to theater are frequent.…”

“…15 There have been promising results in the literature, with good return to function and ease of use. 15,16 However, a significant rate of device failure has been reported, 16,17 with up to 25% of patients never achieving the desired distraction length. 17 The intramedullary skeletal kinetic distractor (ISKD) was first developed by Cole et al 18 in 2001.…”

“…15,16 However, a significant rate of device failure has been reported, 16,17 with up to 25% of patients never achieving the desired distraction length. 17 The intramedullary skeletal kinetic distractor (ISKD) was first developed by Cole et al 18 in 2001. The essential design element consists of a wider diameter ''nail'' into which a sliding narrower diameter ''nail'' engages via a unidirectional ratchet.…”