Correction of Multiapical Deformities of Long Bones of the Lower Extremities: A Review

Abstract

Background. Multiapical deformities of the long bones of the lower extremities represent a complex and widely prevalent orthopedic pathology. A numerous of publications address its individual aspects: diagnosis, planning, and correction. However, no single study was found that offers a comprehensive assessment of contemporary views on treating patients with multiapical deformities of long bones. Aim of the review — to define current concepts and unresolved issues in the analysis, planning, and correction of multiapical deformities of the long bones of the lower limbs based on the scientific literature. Methods. Electronic databases were utilized for literature search: PubMed/MEDLINE, SAGE Publishing Journals, Embase, eLIBRARY, Google Scholar. Particular attention was paid to studies that provide information on diagnosis, planning, and correction methods for multiapical deformities. A total of 46 publications were included in the review. Results. In the literature, the terms “multiapical deformity” and “multilevel deformity” are used synonymously. At the same time, the term “multilevel deformity” is used to denote uniapical deformities of different limb segments. The main diagnostic feature of a multiapical deformity is the location of the apex outside the bone. Unlike uniapical deformities, the correction planning of multiapical deformities uses the axis of the intermediate fragment(s). Most authors define it as the mid-diaphyseal line. The correction of multiapical deformities is performed either acute or gradually. Acute correction with internal fixation is undoubtedly more comfortable for the patient. If there are contraindications to it, the deformity correction is performed gradually using Ilizarov hinges or orthopedic hexapods. Conclusion. The term “multiapical deformity” inherently indicates that the deformed bone has more than one apex, so it should take precedence over the term “multilevel deformity”. The diagnostic feature of the multiapical deformity “localization of the AOD outside the bone” is not absolute and requires clarification. There are challenges in planning the correction using mechanical axes, as well as in determining the axis of the nonlinear (bowing) intermediate fragment(s). The “spring technique” has significant advantages over other variants of using orthopedic hexapods in correcting a multiapical deformity. However, a rationale for the optimal characteristics of springs, their fixation points to supports, and clarification of the computer program’s use method is required. Addressing these issues will enhance the treatment efficiency for patients with multiapical deformities.