Minimally invasive calcaneal osteotomy

Abstract

Category: Hindfoot Introduction/Purpose: A calcaneal osteotomy can be used to treat a variety of pathologic entities in which the hindfoot needs realignment. Minimally invasive calcaneal osteotomy (MICO) is becoming increasingly popular due to being soft tissue friendly, its ability to place other incisions nearby and high union rate. Previous studies have look specifically at medialising MICO or comparing open calcaneal osteotomy versus MICO. The purpose of our study was to compare 3 different types of commonly used MICO in our centre. Methods: Sixty-two MICO which fit the criteria were included in this study. They were performed in our unit from 2010 and 2016 and all patients had at least one year follow up data. The type of osteotomies was as follows: Medialising, n = 34, Lateralising, n =15 and Zadek (Dorsal closing wedge), n =13. Clinical and radiographic data were recorded. The diagnosis for 31/34 of the medialising MICO was Stage 2 PTTD, the diagnosis for 12/15 of the lateralising MICO was cavus foot, while the diagnosis for all Zadek MICO was for insertional Achilles tendinopathy. Apart from the Zadek MICO, the other MICO were all associated with other procedures. The average age (years) were as follows: Medialising, 58 (30 – 74); Lateralising, 33 (14 – 67) and Zadek, 47 (42-62). Results: The average calcaneal displacement was 10.2 (range: 8 – 12) mm for medialising MICO, and 6.6 (4 – 8) mm for lateralising MICO(p=0.021). Average time to union was 7.8 (5.4 – 11.6) weeks for medialising MICO, 6.2 (4.6 to 7.9) weeks for lateralising MICO, and 6.1 (4.1 – 7.6) weeks for Zadek MICO. All the MICO healed radiologically and clinically. Five (8%) patients (Medialising, n = 2; Lateralising n =2; Zadek, n =1) reported transient sural nerve paraesthesia following surgery. Wound problems developed in 5 patients (Lateralising, n =3; Zadek, n =2). The number of total complications were as follow: Medialising, n = 5, Lateralising, n = 7 and Zadek, n =5. Average length of stay was as follows: Medialising, 2(0-8) days; Lateralising, 1(0-3) day and Zadek, 1(0-3) day. Conclusion: Minimally invasive calcaneal osteotomy was safe with a high union rate and low complication rates and length of stay across all 3 common osteotomies. The average calcaneal displacement was significantly less for lateralising than medialising which is similar to reported figures for open osteotomy. Wound problems were more likely for lateralising and Zadek MICO compared to medialising and this could be because of how the osteotomies are shifted.