Reduction and internal fixation of displaced intra-articular calcaneal fractures with a locking nail: a prospective study of sixty nine cases.

PURPOSE: The best treatment for intra-articular fractures of the calcaneus is still debated. The aims of this study were to determine whether intrafocal reduction of thalamic fractures is effective, to evaluate whether a locking nail is able to maintain reduction of the articular surface and to analyse the functional results of this original method. METHODS: This prospective study assessed 69 fractures treated with a locking fracture nail in 63 cases and with primary subtalar fusion in six (Calcanail (®), FH). Articular congruity and global reduction of the calcaneus was assessed in all patients by computed tomography (CT) scan three months postoperatively. Functional results were evaluated according to the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS-AHS) and all complications recorded. RESULTS: For the 63 fracture nails, the average AOFAS score was 85.9 at a mean final follow-up of 12 months. Only three secondary fusions were performed. For the six comminuted fractures requiring primary fusion, the average AOFAS score was 75.9 at the last follow-up. CONCLUSIONS: The posterior intrafocal approach for both reduction and locked nailing of intra-articular calcaneal fractures has been proven as an effective and reliable procedure.

Primary stability of an intramedullary calcaneal nail and an angular stable calcaneal plate in a biomechanical testing model of intraarticular calcaneal fracture.

BACKGROUND: Nowadays, open anatomic reduction and internal fixation can be considered as a valuable treatment for displaced intra-articular fractures of the calcaneus. However, the application of a calcaneal plate via an extensile lateral approach is at risk for a substantial rate of complications including delayed healing, skin necrosis, or infection. There is some evidence that a limited exposure might contribute to a decreased soft tissue complication rate bearing in mind that most minimally invasive techniques have to accept a reduced primary stability compared with the open application of an angular stable plate. Recently, an intrafocal minimal invasive reduction technique has been established employing an intramedullary nail for fracture stabilisation and support of the subtalar joint. The aim of this study was to compare the primary biomechanical performance of the new device versus lateral angular stable plating. MATERIAL AND METHODS: Biomechanical testings were performed on 14 human cadaveric feet (7 pairs). Dry calcaneal bones were fractured resulting in a Sanders type IIB fracture pattern and fixed by either a calcaneal locking plate or an intramedullary calcaneal nail. Compressive testing via the corresponding talus was employed at a constant loading velocity until failure with an universal testing machine and a specific mounting device to avoid any shear forces. Apart from the data of the load deformation diagram the relative motion of the fracture elements during loading was recorded by 8 extensometric transducers. After failure the specimens were carefully examined to check the failure patterns. RESULTS: The displacement of the subtalar joint fragment was substantially lower in specimens fixed with the nail. Stiffness and load to failure were significantly higher after fixation with the intramedullary nail than after application of the angular stable plate. Failure with both fixation modes generally occurred at the anterior calcaneal process fragment. CONCLUSIONS: The primary stability of an intramedullary nail appeared to be superior to an angular stable plate representing the present standard technique in open reconstruction of the fractured calcaneus. The results from the experimental model speak in favour of the clinical use of the intramedullary calcaneal nail.

[3-dimensional imaging of thalamic fractures of the calcaneum. Validation of classifying fractures into 3 forms]. / L'imagerie en trois dimensions dans les fractures thalamiques du calcaneum. Validation de la classification de ces fractures en trois formes.

UNLABELLED: Three dimensional CT scans enables to visualize the calcaneum and to follow the fracture pattern without any risk of errors. PURPOSE OF THE STUDY: This technique has been used to validate our previous classification (using three forms: vertical, horizontal, and mixed) which resulted from a two dimensional tomodensitometric study. MATERIAL: The study was based on a series of 74 fractures, all of them studied with 3D CT and 71 of which were operated. METHOD: The previous classification relied on correlation between lateral radiographs and position on coronal CT plane of the Palmer's fracture line. This we called the Fundamental Line (FL); so the vertical form had medial fundamental line, with thalamic verticalization; and so that the horizontal form with thalamic horizontalization had a lateral FL; the mixed form had a medio thalamic FL with double contoured image. RESULTS: In vertical fractures (16 cases, i.e. 20 per cent), the FL was seen denting the thalamus inwards, continuing forward and damaging the forward facet in about two thirds of cases. The thalamic fragment tilted on its axes frequently, with a great rotation movement; in about half cases, it extended backwards (propagated variation). This lateral fragment, called "cortico thalamic" (CT) explained the vertical thalamic x-ray image. In the horizontal fractures (15 cases, i.e. 20 per cent), the FL dents the thalamus outwards, the medial fragment, pushed downwards, explaining the horizontal image. In the mixed cases (40 cases i.e. 55 per cent) the FL was medio thalamic; the two fragments, downed medially and tilted laterally, are of equivalent importance, hence the double contoured image. In half cases, an accessory line separates the sustentaculum tali, creating the two lined mixed form (14 cases i.e. 35 per cent of the mixed). In those cases, the medial thalamic fragment is unsoldered, when in 50 per cent of cases (i.e. 7 out of 14), the pre-thalamic line, following the sinus tarsi, separates it from the forward part and completely isolates it. Therefore, the initial classification in three forms was in fact confirmed. Moreover, the fundamental line appears in all three forms, being the boundary between the lateral thalamic fragment (always tilted) and the medial fragment (always pushed downside). The anterior of cuboidian joint facets are frequently damaged by the forward prolongation of the Fundamental Line according to studied cases. DISCUSSION: This three form classification emphasizes the role of the Fundamental Line, which in effect acts as a boundary between the two typical displacements of this fracture: downward or rotation movement of the thalamic fragments (since it is there that the main displacements occur). A comparison with the Eastwood and Sanders classifications has been carried out. CONCLUSION: This three dimensional CT approach validates, visualizes and completes the three form classification. This will help us to understand fracture displacements in different forms, and therefore, the particular fracture reduction and osteosynthesis best suited for each case.