Use of Intramedullary Locking Nail for Displaced Intraarticular Fractures of the Calcaneus: What is the Evidence?

CATEGORY: Trauma INTRODUCTION/PURPOSE: There is increasing interest on how to best manage displaced intraarticular calcaneal fractures (DIACF). Intramedullary locking devices (ILDs) have recently been advocated since the technique adopts a minimally invasive approach which may minimise complications and therefore improve outcomes. We reviewed the literature of commercially available devices to identify their characteristics, efficacy and safety. METHODS: Medline, Scopus and EMBASE databases were searched to identify studies reporting use of ILDs for treating DIACF. A PRISMA checklist was used to sort eligible studies. Technical notes and biomechanical studies were first reviewed. Cohort studies were then reviewed for demographics, surgical technique, postoperative protocol, clinical and radiographic scores, complications and reoperations. The modified Coleman Methodology Score (CMS) was used to assess the quality of studies. RESULTS: Thirteen studies investigated two devices (Calcanail; C-Nail). Four technical notes described how to use these devices and three biomechanical studies proved they offered adequate primary stability, stiffness, interfragmentary motion and load to failure. Seven clinical studies (302 feet, 289 patients) demonstrated satisfactory clinical (AOFAS, VAS) and radiographic (Bohler’s angle, Gissane angle, Goldzak index, posterior facet step-off) outcome at 16-months average follow-up. Metalware irritation (up to 20%) and temporary nerve entrapment symptoms (up to 30%) were the most common complications; soft tissue issues were reported in 3-5% of cases. Conversion to subtalar fusion was necessary in 4-6% of cases. Four (57%) studies were authored by implant designers and in 5 (71%) relevant conflict of interest were disclosed. Mean CMS was 61 (moderate quality). CONCLUSION: Treating DIAFCs with ILDs leads to satisfactory clinical outcomes at short term follow-up, enabling restoration of calcaneal height and improved subtalar joint congruency. Metalware irritation and temporary nerve entrapment symptoms are common complications although wound complications including infection and wound breakdown are less frequent than after open lateral approaches. The quality of evidence provided so far is only moderate and biased by potential conflict of interest, raising concerns about the generalisability of results.