Results of open reduction internal fixation versus percutaneous iliosacral screw fixation for unstable pelvic ring injuries: retrospective study of 36 patients.

INTRODUCTION: Surgical stabilization of posterior pelvic ring fractures can be achieved by closed reduction and percutaneous fixation (CRPF) or by open reduction and internal fixation (ORIF). The aim of the present study is to compare the clinical results of both methods. MATERIAL AND METHODS: Medical records of 36 patients consecutively operated for unstable pelvic ring injuries were retrospectively reviewed. We compared 22 patients treated with CRPF versus 14 patients stabilized by using ORIF between 2007 and 2017. The Majeed and Pohlemann scores were used to evaluate postoperative functional outcomes. Complications like blood loss, infection rate, Neurological injury, the operative time and the length of hospital stay were analyzed. RESULTS: The median Majeed pelvic score was 87 points for the CRPF technique compared with 69 points for the ORIF technique. The median Pohlemann score, operative time and length of hospitalization were similar between the two groups. The median blood loss for the CRPF technique was 300 ml compared to 500 ml for the ORIF technique. CRPF and ORIF procedure had each one neurological lesion. There was one case of infection in the ORIF group and none in the CRPF group. No measurements except for the blood loss have reached the significance threshold. CONCLUSION: The CRPF technique shows a clear decrease in blood loss. There was no statistically significant difference in the functional results, infection rate, neurological injury, operative time and hospital stay between both techniques.

Practical guidelines for the treatment of patellar fractures in adults.

The role of the patella is paramount in the transmission of the quadriceps muscle forces, the increase of the lever arm, the distribution of the forces on the trochlea and the centring of the extensor apparatus. Despite the low incidence of patellar factures in comparison with other lower limb fractures, the painful and functional complications, such as knee stiffness, loss of extension and patellofemoral osteoarthritis, can be very disabling and will often compromise the return to a professional or recreational activity and induce falls in the elderly population. Treatment can be conservative or surgical, provided that it is adapted to the type of fracture. Undisplaced fractures with an intact extensor mechanism can be treated nonoperatively. Surgical treatment is recommended for fractures that either disrupt the extensor mechanism or have more than 2 to 3 mm of step-off and more than 1 to 4 mm of displacement. Tension band fixation is the most commonly employed surgical technique. In most cases, hardware has to be removed after fracture healing because of implant-related pain. Operative treatment of comminuted patellar fractures presents a significant challenge to surgeons. Failure to restore the articular surface contour results in posttraumatic arthritis. Anatomical reconstruction of the articular surface is the only way to prevent the development of posttraumatic osteoarthritis. Typically, fracture classification and thus treatment choice are based on anteroposterior and lateral radiographs of the knee, but when computed tomography of the knee was performed pre-operatively, both the classification and treatment were modified thanks to a better understanding of the fracture complexity. The purpose of this article is to review current treatment strategies and optimise the management of adult patients with patellar fractures.

[Stress fractures]. / Les fractures de stress.

A stress fracture is a bony overuse lesion resulting from an imbalance between the osseous regeneration and resorption in favor of the second one. There are two different types, the fatigue fracture that affects mainly the young and active and appears after an abrupt increase of the constraints, and the insufficiency fracture that affects mainly the elderly suffering from a diminished bone density and appears typically during physiological constraints. A thorough screening of the patient's history is mandatory in diagnostics, and MRI is currently the imagery of choice. As the treatment is time consuming and depends on the risk of potential complications that may occur depending on the localization of the fracture, prevention is of key importance and requires a multidisciplinary approach.

Une fracture de stress constitue une lésion osseuse par usure qui résulte d'un déséquilibre entre la régénération et la résorption osseuse en favorisant celle-ci. Il existe deux types différents, la fracture de fatigue qui touche plutôt les sujets jeunes et actifs et qui apparaît lors d'une augmentation brutale des contraintes, et la fracture par insuffisance qui touche plutôt les personnes âgées atteintes d'une densité minérale osseuse diminuée et qui apparaît typiquement lors de contraintes physiologiques. L'anamnèse constitue l'un des points clés du diagnostic, et l'IRM est actuellement l'imagerie de choix. Comme le traitement est long et dépend du risque de complications potentielles pouvant survenir en raison de la localisation de la fracture, la prévention est d'une importance cardinale et nécessite une approche pluridisciplinaire.

Human Bone Progenitor Cells for Clinical Application: What Kind of Immune Reaction Does Fetal Xenograft Tissue Trigger in Immunocompetent Rats?

The potential of human fetal bone cells for successful bone regeneration has been shown in vivo. In particular, it has been demonstrated that the seeding of these cells in porous poly-(l-lactic acid)/ß-tricalcium phosphate scaffolds improved the bone formation compared to cell-free scaffolds in skulls of rats. However, even if the outcome is an improvement of bone formation, a thorough analysis concerning any immune responses, due to the implantation of a xenograft tissue, is not known. As the immune response and skeletal system relationship may contribute to either the success or failure of an implant, we were interested in evaluating the presence of any immune cells and specific reactions of human fetal cells (also called human bone progenitor cells) once implanted in femoral condyles of rats. For this purpose, (1) cell-free scaffolds, (2) human bone progenitor cells, or (3) osteogenic human bone progenitor cells within scaffolds were implanted over 3, 7, 14 days, and 12 weeks. The key finding is that human bone progenitor cells and osteogenic human bone progenitor cells do not trigger any particular specific immune reactions in immunocompetent rats but are noted to delay some bone formation.

[Prevention of perioperative infections in orthopaedic surgery - Role of general practitioner]. / Prévention des infections périopératoires en orthopédie : le rôle du médecin généraliste.

Total joint replacement comes with a high success rate and has been shown to have a very positive impact on our patients suffering from arthritis. Against all efforts about 2 % of our patients will suffer an implant related infection. As the treatment of infected arthroplasties is difficult and expensive the knowledge of risk factors is becoming more and more important for the treatment team in order to improve our preventive measures. Prevention must be performed pre-, intra- and postoperatively. Preoperative optimization of blood sugar levels, nutritional status and correction of general anaemia for example are paramount and the general practitioner as well as the surgeon should be aware of these and other modifiable risk factors in order to operate on the patient in the best possible conditions.

La chirurgie prothétique est une chirurgie dont l'impact est extrêmement favorable pour nos patients souffrant d'une arthrose. Malgré des progrès considérables pour diminuer le taux d'infections postopératoires, cette complication grave survient dans encore environ 2 % des cas. La prévention joue un rôle très important pour diminuer l'incidence de ces infections, à la fois en pré, péri et postopératoire. Le chirurgien et le médecin traitant doivent connaître, rechercher et prendre en charge les facteurs de risque connus d'infection avant toute chirurgie orthopédique. Les principaux facteurs de risque souvent modifiables comme les hyperglycémies, les anémies et la dénutrition seront discutés dans cet article.

Does locally delivered Zoledronate influence peri-implant bone formation? - Spatio-temporal monitoring of bone remodeling in vivo.

Bisphosphonates are known for their strong inhibitory effect on bone resorption. Their influence on bone formation however is less clear. In this study we investigated the spatio-temporal effect of locally delivered Zoledronate on peri-implant bone formation and resorption in an ovariectomized rat femoral model. A cross-linked hyaluronic acid hydrogel was loaded with the drug and applied bilaterally in predrilled holes before inserting polymer screws. Static and dynamic bone parameters were analyzed based on in vivo microCT scans performed first weekly and then biweekly. The results showed that the locally released Zoledronate boosted bone formation rate up to 100% during the first 17 days after implantation and reduced the bone resorption rate up to 1000% later on. This shift in bone remodeling resulted in an increase in bone volume fraction (BV/TV) by 300% close to the screw and 100% further away. The double effect on bone formation and resorption indicates a great potential of Zoledronate-loaded hydrogel for enhancement of peri-implant bone volume which is directly linked to improved implant fixation.

Medial migration of lag screw after gamma nailing.

Fractures of the proximal femur are common in the elderly population. Intramedullary nailing has become the standard treatment for intertrochanteric fractures although several extramedullary implants (e.g. dynamic hip screw (DHS), blade plate, locking compression plate (LCP), etc.) exist. However, despite this being a very common operation in traumatology, there are numerous associated complications. We report the rare complication of the migration of the medial lag screw into the pelvis at five and a half weeks postoperatively. The implant was removed and replaced by a total hip arthroplasty with simultaneous grafting of the acetabular defect and strapping of the greater trochanter. The evolution was favourable. We also present a review of the literature and analyze our case.

[Periprosthetic fractures]. / Fractures périprothétiques.

A periprosthetic fracture is a fracture around or in proximity of a prosthetic implant. As more and more prostheses are implanted, the incidence of periprosthetic fractures also increases. Several risk factors have been outlined, some due to the patient, and some due to the implant itself. Key points in diagnosis are the case history and the imaging, as they allow the distinction between a well-fixed and a loose prosthesis. Correct classification is crucial for the treatment choice, which can be non-operative or consist in an osteosynthesis or in a revision arthroplasty, depending on the patient's general medical condition and the local status.

In Vitro Activity of Gentamicin-Loaded Bioabsorbable Beads against Different Microorganisms.

Osteomyelitis is responsible for high treatment costs, long hospital stays, and results in substantial morbidity. Treatment with surgical debridement and antibiotic-impregnated Polymethylmetacrylate (PMMA) beads is the standard of care, providing high local but low serum antibiotic concentrations, thereby avoiding systemic toxicity. However, for several reasons, the beads require surgical removal. Alternative antibiotic delivery systems should improve the treatment of bone infection, actively encourage bone healing and require no additional surgery for removal. We investigated the activity of gentamicin-loaded bioabsorbable beads against different microorganisms (Staphylococcus epidermidis, S. aureus, Escherichia coli, Enterococcus faecalis, Candida albicans) commonly causing surgical site bone infection, by microcalorimetry. Calcium sulphate beads containing gentamicin were incubated in microcalorimetry ampoules containing different concentrations of the corresponding microorganism. Growth medium with each germ and unloaded beads was used as positive control, growth medium with loaded beads alone as negative control. Bacterial growth-related heat production at 37 °C was measured for 24 h. Cultures without gentamicin-loaded beads produced heat-flow peaks corresponding to the exponential growth of the corresponding microorganisms in nutrient-rich medium. In contrast, cultures with gentamicin-loaded beads completely suppressed heat production during 24 h, demonstrating their antibiotic activity. Gentamicin-loaded beads effectively inhibited growth of susceptible microorganisms, under the described in vitro conditions.

[Pseudarthrosis of the long bones]. / Pseudarthroses aseptiques des os longs.

5 to 10% of all fractures present with a delayed union, whereas 1 to 5% progress to a nonunion, which can be defined as a fracture older than 6 months and lacks any potential to heal without any further intervention. Different fracture and patient related risk factors exist, and the management of a nonunion needs a thorough clinical, radiological and biological workup to classify them in one of the two main categories, the viable nonunions that need essentially more stability, usually by a more rigid fixation, and the non-viable nonunions that need essentially a biological stimulation by decortication and bone grafting. This treatment still remains the first choice with bony healing obtained in 85 to 95% of cases, but it also comes along with certain risks, and some valuable alternatives exist if chosen on the basis of rigid criteria.

Pedicle screw insertion: robotic assistance versus conventional C-arm fluoroscopy.

Bone-mounted robotic guidance for pedicle screw placement has been recently introduced, aiming at increasing accuracy. The aim of this prospective study was to compare this novel approach with the conventional fluoroscopy assisted freehand technique (not the two- or three-dimensional fluoroscopy-based navigation). Two groups were compared: 11 patients, constituting the robotical group, were instrumented with 64 pedicle screws; 23 other patients, constituting the fluoroscopic group, were also instrumented with 64 pedicle screws. Screw position was assessed by two independent observers on postoperative CT-scans using the Rampersaud A to D classification. No neurological complications were noted. Grade A (totally within pedicle margins) accounted for 79% of the screws in the robotically assisted and for 83% of the screws in the fluoroscopic group respectively (p = 0.8). Grade C and D screws, considered as misplacements, accounted for 4.7% of all robotically inserted screws and 7.8% of the fluoroscopically inserted screws (p = 0.71). The current study did not allow to state that robotically assisted screw placement supersedes the conventional fluoroscopy assisted technique, although the literature is more optimistic about the former.