Correlation between cephalic screw positioning of Standard Gamma 3 Nail for intertrochanteric fractures and cut-out incidence.

INTRODUCTION: Lateral fractures of proximal femur are the most frequent fractures in elderly people. Internal fixation using medullary nails is the gold standard of treatment (Gamma 3 nail is the most implanted device) due to reduced incidence of complications than other devices. We report our experience in treating this kind of fractures with Gamma 3 nail, between January 2015 and December 2021. METHODS: We performed a retrospective cohort study of patients treated in our orthopaedic department; level of clinical care is III: 559 patients (431 females and 128 males, with an average age of 85.3 years) with lateral femoral neck fracture. All patients were surgically treated with Gamma 3 standard nail (SGN). We evaluated preliminary X-rays to classify fractures, according to AO-OTA classification and post-operative X-ray to verify cephalic screw position site, according to areas described by Cleveland in 1959: we measured tip-to-apex distance (TAD) and tip-to-apex calcar referred distance (CalTAD). Finally Chang reduction quality criteria (CRQC) for fracture reduction of trochanteric fractures were determined using preoperative or postoperative Antero-Posterior (AP) and lateral radiographs in a Picture Archiving and Communication System (PACS). Incidence of cut-out was evaluated in relation with these parameters. Patients were divided into 2 groups: first group had cephalic screw in optimal positions (5-8-9), the other group had cephalic screw in other positions. RESULTS: In 328 patients (58.7%) screw was in positions 5-8-9, in 231 patients (41.2%) screw was in not-optimal position. Median TAD was 19.1 ± 7.0 mm (range = 0.0-50.5); in 463 patients (82.8%) TAD was ≤ 25 mm. Median CalTAD was 21.4 ± 4.7 mm (range = 5.7-39.2); in 105 patients (79.4%) CalTAD was ≤ 25 mm. Cut-out was observed in 8 cases (1.43%). Multivariate analysis showed a significant correlation (p < 0,05) between incidence of cut-out and fracture type 31A2 and with TAD values >25 mm. Cephalic screw position did not influence incidence of cut-out. DISCUSSION: In order to obtain fracture healing with a low risk of failure, in particular cut-out, it is necessary to obtain good reduction of fracture and optimal lag screw position in order to achieve a TAD inferior to 25 mm.

Static vs dinamic short nail in pertrochanteric fractures: experience of two center in Northern Italy.

BACKGROUND: Lateral fractures of proximal femur are the most frequent to treat for the traumatologist surgeon. Intramedullary nailing is the gold standard treatment of this type of fracture. The aim of the study is to analyze the results obtained with the Elos Intrauma nail by the experience of two Departments of Orthopedics and Traumatology ("Guglielmo da Saliceto" Hospital in Piacenza and the Maggiore hospital in Bologna). METHODS: We performed a retrospective cohort study of 400 patients with lateral femoral neck fracture surgically treated with Elos Intrauma standard nail. The examined period is from 1st Jannuary 2018 to 31st Dicember 2020.  In all patients we implanted Elos® - Intrauma nail, a titanium cervical diaphyseal nail, according to the standard technique. RESULTS: We evaluate at a minumum of three months of follow up 286/400 patients. Average follow up was 3.94 months, minimum 3 months and maximum 24 months. We obtain the 96.85 % of fracture healing, recording 33 complications (11.54%). The incidence of surgical revision was 2.8% (8 cases). No mechanical complications was found in stable fractures treated with short nail and without distal locking. CONCLUSIONS: With the use of Elos nail we obtained 95% of radiographic healings within three months with a complication rate comparable to literature report. Distal locking is absolutely recommended in complex fractures, it may be superfluous after careful evaluation of the fracture pattern and morphological characteristics of the femur to be treated; future in-depth studies may narrow the criteria to choose distal locking or non locking.

Piezosurgery in Hallux Valgus Correction: Distal Linear Osteotomy Operative Technique Using Piezoelectric Tools.

Purpose Piezoelectric and ultrasonic vibrations have been used to cut tissues for three decades, in particular, in periodontics. The increasing use of piezosurgery is based on its clinical advantages such as selective cutting, precision, and low-temperature work rates. The authors applied this concept to a new operative field, the foot and ankle pathology and surgery, such as hallux valgus corrective distal linear osteotomy. Methods The osteotome equipped was the Surgysonic Moto-II model (Esacrom, Imola, Italy), a system recently developed for cutting bone withmicrovibrations. Tips used in author's case series were a high-efficiency five teeth piezoelectric saw and a high-efficiency flat scalpel shaped on three edges. Operative technique is described. Discussion and Conclusion Piezoelectric techniques were developed in response to the need for great precision and safety in bone surgery that was availavle with other manual and rmotorised instruments. Piezo-technology allows minimally-invasive and percutaneous surgery, with reduced trauma on periostium, bone, and soft tissues, reduced healing time of the osteotomy due to the absence of bony necrosis and debris formation and major precision.

Posterior tibial tendon displacement behind the tibia and its interposition in an irreducible isolated ankle dislocation: a case report and literature review.

Isolated posteromedial ankle dislocation is a rare condition thanks to the highly congruent anatomical configuration of the ankle mortise, in which the medial and lateral malleoli greatly reduce the rotational movement of the talus, and the strength of the ligaments higher than the malleoli affords protection against fractures. However, other factors, like medial malleolus hypoplasia, laxity of the ligaments, peroneal muscle weakness and previous ankle sprains, could predispose to pure dislocation. In the absence of such factors, only a complex high-energy trauma, with a rotational component, can lead to this event. Irreducibility of an ankle dislocation, which is rarely encountered, can be due to soft tissue interposition. Dislocation of the posterior tibial tendon can be the cause of an irreducible talar dislocation; interposition of this tendon, found to have slid posteriorly to the distal tibia and then passed through the tibioperoneal syndesmosis, is reported in just a few cases of ankle fracture-dislocation.

Magnetic forces and magnetized biomaterials provide dynamic flux information during bone regeneration.

The fascinating prospect to direct tissue regeneration by magnetic activation has been recently explored. In this study we investigate the possibility to boost bone regeneration in an experimental defect in rabbit femoral condyle by combining static magnetic fields and magnetic biomaterials. NdFeB permanent magnets are implanted close to biomimetic collagen/hydroxyapatite resorbable scaffolds magnetized according to two different protocols . Permanent magnet only or non-magnetic scaffolds are used as controls. Bone tissue regeneration is evaluated at 12 weeks from surgery from a histological, histomorphometric and biomechanical point of view. The reorganization of the magnetized collagen fibers under the effect of the static magnetic field generated by the permanent magnet produces a highly-peculiar bone pattern, with highly-interconnected trabeculae orthogonally oriented with respect to the magnetic field lines. In contrast, only partial defect healing is achieved within the control groups. We ascribe the peculiar bone regeneration to the transfer of micro-environmental information, mediated by collagen fibrils magnetized by magnetic nanoparticles, under the effect of the static magnetic field. These results open new perspectives on the possibility to improve implant fixation and control the morphology and maturity of regenerated bone providing "in site" forces by synergically combining static magnetic fields and biomaterials.

The prospective opportunities offered by magnetic scaffolds for bone tissue engineering: a review.

Magnetic scaffolds are becoming increasingly attractive in tissue engineering, due to their ability to enhance bone tissue formation by attracting soluble factors, such as growth factors, hormones and polypeptides, directly to the implantation site, as well as their potential to improve the fixation and stability of the implant. Moreover, there is increasing evidence that the synergistic effects of magnetic scaffolds and magnetic fields can promote bone repair and regeneration. In this manuscript we review the recent innovations in bone tissue engineering that exploit magnetic biomaterials combined with static magnetic fields to enhance bone cell adhesion and proliferation, and thus bone tissue growth.

A new approach to scaffold fixation by magnetic forces: Application to large osteochondral defects.

Scaffold fixation represents one of the most serious challenges in osteochondral defect surgery. Indeed, the fixation should firmly hold the scaffold in the implanted position as well as it should guaranty stable bone/scaffold interface for efficient tissue regeneration. Nonetheless successful results have been achieved for small defect repair, the fixation remains really problematic for large defects, i.e. defects with areas exceeding 2cm(2). This paper advances an innovative magnetic fixation approach based on application of magnetic scaffolds. Finite element modeling was exploited to investigate the fixation efficiency. We considered three magnetic configurations: (1) external permanent magnet ring placed around the leg near the joint; (2) four small permanent magnet pins implanted in the bone underlying the scaffold; (3) four similarly implanted stainless steel pins which magnetization was induced by the external magnet. It was found that for most appropriate magnetic materials and optimized magnet-scaffold positioning all the considered configurations provide a sufficient scaffold fixation. In addition to fixation, we analyzed the pressure induced by magnetic forces at the bone/scaffold interface. Such pressure is known to influence significantly the bone regeneration and could be used for magneto-mechanical stimulation.