Femoral Reconstruction Using External Fixation

Background. The use of an external fixator for the purpose of distraction osteogenesis has been applied to a wide range of orthopedic problems caused by such diverse etiologies as congenital disease, metabolic conditions, infections, traumatic injuries, and congenital short stature. The purpose of this study was to analyze our experience of utilizing this method in patients undergoing a variety of orthopedic procedures of the femur. Methods. We retrospectively reviewed our experience of using external fixation for femoral reconstruction. Three subgroups were defined based on the primary reconstruction goal lengthening, deformity correction, and repair of nonunion/bone defect. Factors such as leg length discrepancy (LLD), limb alignment, and external fixation time and complications were evaluated for the entire group and the 3 subgroups. Results. There was substantial improvement in the overall LLD, femoral length discrepancy, and limb alignment as measured by mechanical axis deviation (MAD) and lateral distal femoral angle (LDFA) for the entire group as well as the subgroups. Conclusions. The Ilizarov external fixator allows for decreased surgical exposure and preservation of blood supply to bone, avoidance of bone grafting and internal fixation, and simultaneous lengthening and deformity correction, making it a very useful technique for femoral reconstruction

Treatment of Angular Deformity and Limb Length Discrepancy With a Retrograde Femur Magnetic Intramedullary Nail: A Fixator-assisted, Blocking Screw Technique

Background: Fixator-assisted nailing techniques that incorporate magnetic internal lengthening nails (MILNs) permit acute deformity correction and then gradual limb lengthening without needing postoperative external fixators. Purposes: We sought to investigate the safety and accuracy of a fixator-assisted, blocking screw technique using retrograde MILNs for the correction of LLD and limb malalignment. Methods: Forty-one patients (13 patients with genu varum and 28 patients with genu valgum) with LLD treated with fixator-assisted, blocking screw retrograde MILN reconstruction were included. Preoperative LLD, mechanical axis deviation, and joint orientation angles were compared with values at the end of treatment, and bone healing indices were calculated. Perioperative complications were tracked. Results: Preoperatively, the mean mechanical lateral distal femoral angle of the varus cohort was 98 ± 12°, whereas the mean lateral distal femoral angle of the valgus cohort was 82±4°. Both cohorts had an average 3-cm LLD. 99% of the planned limb lengthening was achieved. Final LDFAs were 91 ± 6° and 89 ± 4° in the varus and valgus cohorts, respectively, and the limb mechanical axis angles were normalized. 10 patients underwent a total of 21 returns to the operating room. Most commonly, this involved percutaneous injection of bone marrow aspirate concentrate to bone regenerate exhibiting delayed union (6 patients). Conclusions: The use of a retrograde MILN with a fixator-assisted, blocking screw technique is an effective means of acute deformity correction and gradual limb lengthening through minimal incisions. The accuracy of deformity correction relies on intraoperative execution of the appropriate nail start site, osteotomy location, and placement of blocking screws

Limb Lengthening and Reconstruction Society AIM Index Reliably Assesses Lower Limb Deformity

Abstract Background Although several systems exist for classifying specific limb deformities, there currently are no validated rating scales for evaluating the complexity of general lower limb deformities. Accurate assessment of the complexity of a limb deformity is essential for successful treatment. A committee of the Limb Lengthening and Reconstruction Society (LLRS) therefore developed the LLRS AIM Index to quantify the severity of a broad range of lower extremity deformities in seven domains. Questions/Purposes We addressed two questions: (1) Does the LLRS AIM Index show construct validity by correlating with rankings of case complexity? (2) Does the LLRS AIM Index show sufficient interrater and intrarater reliabilities? Methods We had eight surgeons evaluate 10 fictionalized patients with various lower limb deformities. First, they ranked the cases from simplest to most complex, and then they rated the cases using the LLRS AIM Index. Two or more weeks later, they rated the cases again. We assessed reliability using the Kendall's W test. Results Raters were consistent in their rankings of case complexity (W = 0.33). Patient rankings also correlated with both sets of LLRS AIM ratings (r 2 = 0.25; r 2 = 0.23). The LLRS AIM Index showed interrater reliability with an intraclass correlation (ICC) of 0.97 for Trial 1 and 0.98 for Trial 2 and intrarater reliability with an ICC of 0.94. The LLRS AIM Index ratings also were highly consistent between the attending surgeons and surgeons-in-training (ICC = 0.91). Conclusions Our preliminarily observations suggest that the LLRS AIM Index reliably classifies the complexity of lower limb deformities in and between observers

SYMPOSIUM: 2013 LIMB LENGTHENING AND RECONSTRUCTION SOCIETY What Risk Factors Predict Usage of Gastrocsoleus Recession During Tibial Lengthening?

Abstract Background Tibial lengthening is frequently associated with gastrocsoleus contracture and some patients are treated surgically. However, the risk factors associated with gastrocsoleus contracture severe enough to warrant surgery during tibial lengthening and the consistency with which gastrocsoleus recession (GSR) results in a plantigrade foot in this setting have not been well defined. Questions/purposes We compared patients treated with or without GSR during tibial lengthening with respect to (1) clinical risk factors triggering GSR use, (2) ROM gains and patient-reported outcomes, and (3) complications after GSR. Methods Between 2002 and 2011, 95 patients underwent tibial lengthenings excluding those associated with bone loss; 82 (83%) were available for a minimum followup of 1 year. According to our clinical algorithm, we performed GSR when patients had equinus contractures of greater than 10°while lengthening or greater than 0°before or after lengthening. Forty-one patients underwent GSR and 41 did not. Univariate analysis was performed to assess independent associations between surgical characteristics and likelihood of undergoing GSR. A multivariate regression model and receiver operating characteristic curves were generated to adjust for confounders and to establish risk factors and any threshold for undergoing GSR. Chart review determined ROM, patient-reported outcomes, and complications. Results Amount and percentage of lengthening, age, and etiology were risk factors for GSR. Patients with lengthening of greater than 42 mm (odds ratio [OR]: 4.13; 95% CI: 1.82, 9.40; p = 0.001), lengthening of greater than 13% of lengthening (OR: 3.88; 95% CI: 1.66, 9.11; p = 0.001), and congenital etiology (OR: 1.90; 95% CI: 0.86, 4.15; p = 0.109) were more likely to undergo GSR. Adjusting for all other variables, increased amount lengthened (adjusted OR: 1.05; 95% CI: 1.02, 1.07; p \ 0.001) and age (adjusted OR: 1.02; 95% CI: 0.99, 1.05; p = 0.131) were associated with undergoing GSR. Patients gained 24°of ankle dorsiflexion after GSR. Selfreported functional outcomes were similar between patients with or without GSR. Complications included stretch injury to the posterior tibial nerve leading to temporary and partial loss of plantar sensation in two patients