Surgical treatment of periprosthetic humerus fractures and algorithm. / Tratamiento quirúrgico de las fracturas periprotésicas de húmero y algoritmo de actuación.

INTRODUCTION: Periprosthetic humerus fractures are infrequent and sometimes difficult to treat. There is limited literature and no consensus on the handling of these fractures. The objective of this study was to compare our results with those published in the literature, in order to improve our care and propose a management algorithm. MATERIAL AND METHOD: Observational study of 10cases of periprosthetic humerus fractures with a mean follow-up of the patients of 23months. An analysis of sociodemographic, radiological and surgical variables was performed. They were reviewed clinically and by telephone using the UCLA Shoulder Score and Quick-DASH scales. A systematic search was made in Pubmed for periprosthetic humerus fractures, for a literature review with which to compare our series. RESULTS: We analysed 10patients with an average age of 69.4years (37-91). Of the patients, 90% underwent surgery through open reduction and internal fixation. Nine of the ten patients consolidated in a mean time of 6.2months (range 5-12), the remaining suffered a new fracture 5months after the intervention, who were reoperated and a new osteosynthesis performed with bone allograft. In the UCLA scale there was a decrease of 10.66points, and an increase of 27.3points in the Quick-DASH, at the end of the follow-up. CONCLUSIONS: In our series of cases we found similarities in the literature, in relation to demographic aspects and obtaining good radiographic results, which do not correspond to the functional outcome of patients.

Talus fractures. Functional results for polytraumatized patients. / Fracturas de astrágalo. Resultados funcionales en pacientes politraumatizados.

Talar fractures are uncommon lesions (0.1-0.9%) and have a high rate of complications. One of the situations in which a fracture of the talus can occur is in the context of polytrauma which may further compromise the functional prognosis. The aim of this study was to analyze the functional results in patients with talar fractures whether or not they occurred in the context of polytrauma. Observational study on a retrospective cohort of 24 patients operated in our centre (2008-2016). They were grouped according to whether they were polytraumatized (ISS>16) or not (ISS≤16). Review of sociodemographic, radiographic, functional variables (VAS pain scale and FADI -Foot and Ankle Disability Index-) and the onset of complications such as arthrosis, arthrodesis or avascular necrosis. Review of 25 talar fractures in 24 patients with a mean age of 38 years (19-75) and a mean follow-up of 4.2 years (0.5-9). According to the ISS, 44% of patients (11) were polytraumatized and 56% (14) were not. The average score according to the FADI scale was 62 points for the polytraumatized patients and 76.9 for the non-polytraumatized patients. The pain according to the VAS scale was 5.8 points in the group of polytraumatized patients and 4.3 in the non-polytraumatized patient group. Regarding complications, 64% of the polytraumatized patients and 43% of the non-traumatized patients had a complication. 36% of the polytraumatized patients had clinical and radiological signs of subtalar arthrosis compared to 35% of the non-traumatized patients, of whom 27% underwent arthrodesis compared to 28% of the non-traumatized patients. 27% of the polytraumatized patients were diagnosed with avascular necrosis as opposed to 0% of the non-polytraumatized patients.

Treatment of posttraumatic bone defects of the forearm with vascularized fibular grafts. Follow up after fourteen years.

BACKGROUND: Among several techniques proposed for the reconstruction of posttraumatic bone defects of the forearm, that of free vascularised fibular graft (FVFG) is one of the most widely used. PATIENTS AND METHOD: We study the long-term outcomes of 14 patients who underwent FVFG between 1994 and 2009, with a minimum follow up of 8 years and a maximum of 23 years (mean: 13.9 years). Demographic, clinical and radiological variables were collected retrospectively. The DASH scale was used for clinical assessment. RESULTS: Fourteen patients were operated on by the same surgeon, applying FVFG for the reconstruction of posttraumatic bone defects of the forearm (three septic non-union of the ulna or radius, five radius fractures, two ulna fractures and four fractures of both bones). The maximum length of the defect was 11 cm and the minimum length was 6 cm. In four cases, reconstruction of the two bones was achieved using the double barrel technique, and in another four cases, an osteoseptocutaneous flap was used. Fixation was performed with 3.5 mm reconstruction plates in thirteen cases and with 3.5 mm screws in one case. Consolidation was obtained in 12 cases (85.7%) after an average time of 4.2 months (range: 2-6.5 months). In one case, consolidation of the proximal ulnar fracture site was not achieved, and in another, following the failure of reconstruction attempts, an arthrodesis was performed. At the end of the follow-up period, the patients had an average DASH score of 17.1 points (range 1.8-68.1). CONCLUSIONS: FVFG is a valid option for the reconstruction of posttraumatic bone defects of the forearm. Its use via the double barrel method or as an osteocutaneous composite graft enables the simultaneous reconstruction of both forearm bones and associated soft tissue injuries. Long-term follow-up of patients who have undergone this technique confirms its satisfactory functional and radiological results.

In Vivo Mechanical Characterization of the Distraction Callus During Bone Consolidation.

Understanding the evolution of callus mechanical properties over time provides insights in the mechanobiology of fracture healing and tissue differentiation, can be used to validate numerical models, and informs clinical practice. Bone transport experiments were performed in sheep, in which a distractor type Ilizarov was implanted. The forces through the fixator evolution were measured and the callus stiffness was estimated from these forces. Computerized tomography images were taken and bone volume of the callus at different stages was obtained. The results showed that the maximum bone tissue production rate (0.146 cm³/day) was achieved 20 days after the end of the distraction phase. 50 days after the end of the distraction phase, the callus was ossified completely and had its maximum volume, 6-10 cm³ In addition, 80-90% of the load sustained by the operated limb was recovered and the callus stiffness increased exponentially until 5.4-11.4 kN/mm, still below 10% of the healthy level of callus stiffness. The effects of the bony bridging of the callus and the time of the fixator removal on callus force, stiffness and volume were analyzed. These outcomes allowed relating quantifiable biological aspects (callus volume and tissue production rate) with mechanical parameters (callus force and stiffness) using data from the same experiment.

[Patients with hemodynamic unstable pelvic fractures in extremis: pelvic packing or angiography?]. / Pacientes con fractura de pelvis inestables hemodinámicamente in extremis ¿packing pélvico o arteriografía?

The multidisciplinary management of patients with pelvic trauma has improved prognosis, but mortality is still very high. The appropriate treatment strategy remains controversial, especially regarding the control of bleeding in patients whose clinical situation is extreme by using angiography or pelvic packing. We propose using a tool of evidence-based medicine (CAT) the benefit of the completion of pelvic packing in relation to a specific clinical question from a specific situation. What is best for the management of bleeding, extraperitoneal pelvic packing or angiography, in patients with hemodynamically unstable pelvic fracture in extremis? From this study we can conclude that angiography may improve control of bleeding in patients with arterial bleeding and hemodynamically stable but the packing has priority in patients with pelvic fractures and hemodynamic instability.

Biomechanical analysis of a new minimally invasive system for osteosynthesis of pubis symphysis disruption.

INTRODUCTION: We analysed the effectiveness of a new percutaneous osteosynthesis system for the treatment of pelvis fractures with rotational instability. METHODS: A pre-clinical cross-sectional experimental study wherein Tile type B1 injuries (open-book fractures) were produced in 10 specimens of fresh human cadavers, including the L4-5 vertebrae, pelvic ring, and proximal third of the femur, keeping intact the capsular and ligamentous structures, is presented in this paper. The physiological mobility of the intact pelvis in a standing position post-injury was compared to that following the performance of a minimally invasive osteosynthesis of the symphysis with two cannulated screws. A specially designed test rig capable of applying loads simulating different weights, coupled with a photogrammetry system, was employed to determine the 3D displacements and rotations in three test cases: intact, injured and fixed. RESULTS: After applying an axial load of 300 N, no differences were observed in the average displacement (mm) of the facet joints of the intact pubic symphysis in comparison to those treated with screws (p >0.7). A statistical difference was observed between the average displacements of the sacroiliac facet joints and pelvises with symphyseal fractures treated with screws after the application of a load (p <0.05). CONCLUSION: The symphyseal setting with two crossed screws appears to be an effective alternative to osteosynthesis in pelvic fractures with rotational instability.