Correction outcomes of the postoperative malalignment salvaged by the temporary application of the hexapod external fixator in tibial diaphyseal fractures treated by monolateral external fixation

Abstract

Background: Postoperative malalignment in fractures treated by monolateral external fixation is not uncommon in clinical practice. Accurate reduction without excessive tissue disruption caused by surgical intervention and sequentially manage the fractures using monolateral external fixation for definitive treatment is still a challenge for surgeons. The purpose of our study was to evaluate the feasibility and effectiveness of the temporary application of the hexapod external fixator (HEF) for the postoperative malalignment correction in tibial diaphyseal fractures treated by monolateral external fixation. Methods: We carried out a retrospective analysis of 23 trauma patients with tibial diaphyseal fracture treated by the monolateral external fixation at our institution from January 2016 to May 2019. There were 21 males and 2 females with a mean age of 38 years (range 18-60 years). The hexapod external fixator was temporarily applied due to postoperative malalignment within two weeks and who unwilling to undergo a secondary surgical intervention. For patients with postoperative malalignment requiring correction, the HEF components were installed on the original existing half pins of the monolateral external fixator after removing the connecting rod. The standard anteroposterior and lateral X-rays of the injured limb combined with the temporary HEF were conducted to measure the hexapod external fixator parameters. Any residual deformities were corrected by gradual struts adjustment with the aid of computerbased software. When satisfactory alignment was achieved, the HEF was removed, and the monolateral external fixator was sequentially used as the definitive structure. Results: All patients acquired functional reduction, which was evaluated by radiographs. The mean correction time was 4 days (range 2 to 8 days). The mean coronal plane translation (1.3 ±1.0 mm), coronal plane angulation (0.9 ±0.7 °), sagittal plane translation (1.4 ±1.1 mm), and sagittal plane angulation (0.7 ±0.7 °) after correction were all less than those (7.0 ±4.9 mm, 4.7 ±2.3 °, 5.6 ±3.6 mm, 3.2 ±2.5 °) before correction. Conclusions: The temporary application of the hexapod external fixator is an alternative and feasible method for the postoperative malalignment correction in tibial diaphyseal fractures treated by monolateral external fixation.

Accuracy of the hexapod external fixator in treating tibial angular deformities with or without limb length discrepancy: a retrospective study

“…TSF and SCF, relatively new hexapod fixators, use computer-based deformity planning and provide more versatile correction than the Ilizarov system while allowing even a full weight-bearing mobilization. Because of their versatility, hexapod external fixator systems are increasingly being popular for the treatment of bone deformities, limb length discrepancies (LLD), and joint contractures [16][17][18][19][20][21][22]. However, the main clinical use of hexapod external fixators is still the simultaneous correction of multiplanar deformities.…”