Growth disturbance after lengthening of the lower limb and quantitative assessment of physeal closure in skeletally immature patients with achondroplasia

Abstract

This study evaluated the effect of limb lengthening on longitudinal growth in patients with achondroplasia. Growth of the lower extremity was assessed retrospectively by serial radiographs in 35 skeletally immature patients with achondroplasia who underwent bilateral limb lengthening (Group 1), and in 12 skeletally immature patients with achondroplasia who did not (Group 2). In Group 1, 23 patients underwent only tibial lengthening (Group 1a) and 12 patients underwent tibial and femoral lengthening sequentially (Group 1b). The mean lengthening in the tibia was 9.2 cm (59.5%) in Group 1a, and 9.0 cm (58.2%) in the tibia and 10.2 cm (54.3%) in the femur in Group 1b. The mean follow-up was 9.3 years (8.6 to 10.3). The final mean total length of lower extremity in Group 1a was 526.6 mm (501.3 to 552.9) at the time of skeletal maturity and 610.1 mm (577.6 to 638.6) in Group 1b, compared with 457.0 mm (411.7 to 502.3) in Group 2. However, the mean actual length, representing the length solely grown from the physis without the length of distraction, showed that there was a significant disturbance of growth after limb lengthening. In Group 1a, a mean decrease of 22.4 mm (21.3 to 23.1) (4.9%) was observed in the actual limb length when compared with Group 2, and a greater mean decrease of 38.9 mm (37.2 to 40.8) (8.5%) was observed in Group 1b when compared with Group 2 at skeletal maturity. In Group 1, the mean actual limb length was 16.5 mm (15.8 to 17.2) (3.6%) shorter in Group 1b when compared with Group 1a at the time of skeletal maturity. Premature physeal closure was seen mostly in the proximal tibia and the distal femur with relative preservation of proximal femur and distal tibia. We suggest that significant disturbance of growth can occur after extensive limb lengthening in patients with achondroplasia, and therefore, this should be included in pre-operative counselling of these patients and their parents.

The etiology of short stature affects the clinical outcome of lower limb lengthening using external fixation

“…Recently, in a separate study that was not included in our analysis (due to lack of documented complications), over half of skeletally immature patients with achondroplasia who underwent DO for stature lengthening had substantial growth inhibition and premature physeal closure of the lengthened femurs and tibias (Song et al 2012). Increasing the magnitude of lengthening is also associated with other complications such as adjacent joint stiffness and fractures (Venkatesh et al 2009).…”

Limb lengthening history, evolution, complications and current concepts

“…The incidence of complications is affected by the aetiology of the shortening and magnitude of the regenerated area. Extensive bone lengthening can adversely affect growth in children and increase the possibility of joint contractures [46,47].…”

Hip kinematics and kinetics in persons with and without cam femoroacetabular impingement during a deep squat task

“…Participants in the cam FAI group were recruited from two orthopedic clinics. Persons with cam FAI were eligible if they were skeletally mature (Song et al, 2012), 45 years of age or younger, and had an alpha angle measurement of greater than 50.5° (Beaule et al, 2005;Hack et al, 2010;Kennedy et al, 2009;Lamontagne et al, 2009;Notzli et al, 2002). This cut-off was chosen to be consistent with previous kinematic studies of persons with FAI Lamontagne et al, 2009).…”