Comparative analysis of the lower leg multiapical deformity correction by various methods of orthopedic hexapods usage

Introduction The technique of multiapical deformity correction with orthopaedic hexapods can be accepted as "standard." This requires several software calculations a and lengths changes in the 12–18 struts. The "spring" technique was designed to address these disadvantages.
Purpose To analyze the treatment results of patients with lower leg multiapical deformities corrected by "standard" and "spring" techniques
Methods The data of patient group 1 (standard technique, n = 17) and patient group 2 (spring technique, n = 17), were used. Correction accuracy, duration of correction, and fixation periods were compared. In  patients requiring lengthening, fixation and osteosynthesis indices were additionally analyzed. Quality of life and segment function were assessed using the LEFS questionnaire.
Results There was no statistically significant difference between the groups when comparing each of the parameters studied. When comparing LEFS parameters before external fixation (EF) and 2–3 months after  frame removal, a statistically significant difference was observed in patients within each of the first and second groups.
Discussion The correction accuracy in each group was 94.4 %, which, along with the absence of a significant difference in the duration of treatment and data from the LEFS questionnaire, indicates equal clinical effectiveness of both methods. It was noted that treatment with various modifications of circular external fixators is equally uncomfortable for patients. At the same time, the need for only one calculation in a hexapod software instead of 2–3, the ability to change the length of 6 struts instead of 12–18, as well as simpler assembly and less cumbersome construct if there is small (less than 10–12 cm) distance between the rings are advantages of a "spring" technique.
Conclusion Based on the analysis of the criteria used for evaluation, it can be concluded that the “spring” technique for correcting lower leg multiapical deformities is as effective as the “standard” technique. The  advantages of the "spring" technique are associated with the greater convenience of its use: both for the orthopedic surgeon and the patient.

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