Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

External fixation has evolved from being used primarily as a last resort fixation method to becoming a main stream technique used to treat a myriad of bone and soft tissue pathologies. Techniques in limb reconstruction continue to advance largely as a result of the use of these external devices. A thorough understanding of the biomechanical principles of external fixation is useful for all orthopedic surgeons as most will have to occasionally mount a fixator throughout their career. In this review, various types of external fixators and their common clinical applications are described with a focus on unilateral and circular frames. The biomechanical principles that govern bony and fixator stability are reviewed as well as the recommended techniques for applying external fixators to maximize stability. Additionally, we have illustrated methods for managing patients while they are in the external frames to facilitate function and shorten treatment duration.

Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Background Ankle arthrodesis may be achieved using the Ilizarov method. Comorbidities, such as diabetes, Charcot neuroarthropathy, osteomyelitis, leg length discrepancy, and smoking, can make an ankle fusion complex and may be associated with lower rates of healing. Questions/Purposes We asked if (1) smoking and other comorbidities led to lower fusion rates, (2) time wearing the frame affected outcome, and (3) simultaneous tibial lengthening improved fusion rates. Methods We retrospectively studied 101 patients who underwent complex ankle fusion using the Ilizarov technique. The median time wearing the frame was 25 weeks (range, 10-65 weeks). Twenty-four patients had simultaneous tibial lengthening. The minimum followup for 91 of the 101 patients was 27 months (median, 65 months; range, 27-134 months). Results Fusion was achieved in 76 of 91 patients. Smoking was associated with a 54% rate of nonunion. Fifteen of 19 patients with Charcot neuroarthropathy achieved union but had a high rate of subsequent subtalar joint failure. Time wearing the frame did not affect union rates. Tibial lengthening did not improve ankle fusion rates. Conclusion Smokers should be warned of the high risk of nonunion and we recommend they quit smoking. We also recommend surgeons recognize the higher nonunion rate in patients with Charcot neuroarthropathy. We believe tibial lengthening should not be performed to enhance healing at the fusion site.

One can comprehensively approach tibial nonunions with the TSF. This is particularly useful in the setting of stiff hypertrophic nonunion, infection, bone loss, LLD, and poor soft-tissue envelope. Infected nonunions have a higher risk of failure than noninfected cases. Treatment after fewer failed surgeries will lead to a better outcome. Internal fixation can be used to salvage initial failures.

Background Optimal leg alignment is the goal of tibial osteotomy. The Taylor Spatial Frame (TSF) and the Ilizarov method enable gradual realignment of angulation and translation in the coronal, sagittal, and axial planes, therefore, the term six-axis correction.

Background:Version abnormalities of the femur can cause pain and hip joint damage due to impingement or instability. A retrospective clinical review was conducted on patients undergoing a subtrochanteric derotation osteotomy for either excessive anteversion or retroversion of the femur.Methods:A total of 55 derotation osteotomies were performed in 43 patients: 36 females and 7 males. The average age was 29 years (range, 14 to 59 years). The osteotomies were performed closed with an intramedullary saw. Fixation was performed with a variety of intramedullary nails. Twenty-nine percent of patients had a retroversion deformity (average, −9° of retroversion; range, +2° to −23°) and 71% had excessive anteversion of the femur (average, +37° of anteversion; range, +22° to +53°). The etiology was posttraumatic in 5 patients (12%), diplegic cerebral palsy in 2 patients (5%), Prader-Willi syndrome in 1 patient (2%), and idiopathic in 35 patients (81%). Forty-nine percent underwent concomitant surgery with the index femoral derotation osteotomy, including hip arthroscopy in 40%, tibial derotation osteotomy in 13%, and a periacetabular osteotomy in 5%. Tibial osteotomies were performed to correct a compensatory excessive external tibial torsion that would be exacerbated in the correction of excessive femoral anteversion.Results:No patient was lost to follow-up. Failures occurred in three hips in three patients (5%): two hip arthroplasties and one nonunion that healed after rerodding. There was one late infection treated successfully with implant removal and antibiotics with an excellent final clinical outcome. At an average follow-up of 6.5 years (range, 2 to 19.7 years), the modified Harris Hip Score improved by 29 points in the remaining 52 cases (P < 0.001, Wilcoxon signed-rank test). The results were rated as excellent in 75%, good in 23%, and fair in 2%. Subsequent surgery was required in 78% of hips, 91% of which were implant removals.Conclusions:A closed, subtrochanteric derotation osteotomy of the femur is a safe and effective procedure to treat either femoral retroversion or excessive anteversion. Excellent or good results were obtained in 93%, despite the need for subsequent implant removal in more than two-thirds of the patients.

We feel that ankle distraction offers a promising solution for many people with ankle arthritis.