AO Technical Commission Meet the Experts

Complex congenital as well as acquired deformities in the mandible, the midface or cranium might require gradual correction with distraction osteogenesis. The treatment must be performed such that not only new bone can be formed and finally shaped for better fit, but also surrounding soft tissue can grow during the distraction procedure. CMF distractors are used for patients from the first days of live to almost every age depending on the clinical situation. Callus distraction and final shaping along a guiding fixation allows the correction of very complex deformities and filling of voluminous voids in bone structures. Virtual planning of the distraction vector for callus formation or bone transport as well as the fixation of the distractor and the final reconstruction are nowadays state of the art. Digital planning and simulation may even replace complex calculations, and the production of 3D bone models allow for the visualization and construct planning/testing. Alberto Rocha Pereira presented exemplary cases and emphasized the wide variety of applications of CMF distraction in the mandible and midface area to solve very different clinical problems to improve patient's lives.

Comminuted fractures of the proximal phalanx are common injuries in horses and even though the prognosis for survival is guarded and complications are common, the currently recommended treatment is to immobilize the distal limb in a transfixation cast. Christoph Lischer, Fabrice Rossignol and Jeffrey Watkins from the AO Technical Commission Large Animal Expert Group presented the biological bridge plating using the human LCP Distal Femur Plate which can provide a better alternative with fewer complications and better long-term outcomes. The plate is pre-contoured, low profile, and features combi holes along the shaft and threaded locking holes in the plate head. The left and right version of the human 9- and 11-hole plate has recently been approved for veterinary application, specifically for comminuted P1 fractures in horses. During the highly informative session, the three experts outlined the underlying principle, provided detailed information about surgical steps and exemplified those in a practical demonstration on a bone model. Rossignol, the driving force behind this newly developed technique, underlined the necessary post-operative management including casting, adequate trimming and shoeing in order to improve patient outcomes. More information and clinical cases can be found here.

Patient specific implants (PSIs) and cutting guides are widely used in orthognathic procedures, in orbital and midface trauma, and post-ablative reconstruction of the craniomaxillofacial skeleton. PSIs are available as 3D printed titanium, milled titanium or reinforced PEEK devices depending on application and surgeon preference. Daniel Buchbinder and Damir Matic, key opinion leaders and members of the AO Technical Commission Craniomaxillofacial (AO TC CMF), presented this innovative technique along with comprehensive workflows developed in the AO TC CMF.
The combination of 3D printed implants and 3D printed cutting guides has revolutionized planning and execution of these procedures resulting in improved efficiency in the operating room and more predictable outcomes. The workflow includes 3D imaging, image analysis and segmentation, virtual osteotomy planning, virtual positioning of the bone segments to the desired alignment and occlusion, planning of patient specific implants in the planned position to fix the fragments with predictive screw hole location, planning of the cutting and predictive screw hole drill guides, production of the patient specific implants and guides and finally the execution of the fully guided procedure in the operating room. A number of peer reviewed publications have reported minimal deviations between the planned procedure and the surgical result if the surgical plan is strictly followed. Cutting guides are also produced for the donor site in reconstructive cases following ablative surgery to aid in the harvest and contouring of the bone flap following the virtual reconstructive plan. In addition, the guide also incorporates predictive holes for the fixation of the bone flap to the patient specific milled or 3D printed reconstruction plate. Finally, virtual planning can also be used to determine the ideal location for the placement of endosseous titanium fixtures which will be used to anchor a dental prosthesis, ensuring good functional outcomes for these patients.

Chest wall trauma with multiple rib fractures and flail chest are injuries with mortality rates as high as 20% and major complication rates of up to 40%. The number of surgical procedures for rib fracture stabilization has increased as dedicated implants and instruments became available. The development of improved tools has led surgeons to perform rib fracture fixation through smaller incisions. Innovative surgical techniques make this type of surgery available to an increasing number of patients. Stefan Schulz-Drost and Mario Gasparri, two leading experts in thoracic surgery, provided an insight into minimally invasive rib stabilization using the MatrixRIB Fixation System (for rib and sternum fractures) and the recently developed self-drilling screws. Schulz-Drost provided a comprehensive overview about the different surgical procedures available for the median, lateral, and posterior chest wall regions. A hands-on demonstration led the audience through a minimal invasive procedure for sternal fracture fixation.

Fracture-related infection (FRI) remains a challenging complication and is a heavy burden for orthopedic trauma patients, their families and treating physicians, and for the healthcare systems. Standardization of the diagnosis and treatment of FRI has been lacking, which has made it difficult for researchers to perform and compare studies in this field. In this Meet the Experts session, key opinion leaders in FRI, Willem Metsemakers and Bill Obremskey, presented the recently published consensus recommendations for the diagnosis and treatment of FRI. Developed by an international group of recognized experts in FRI, the evidence-based recommendations encompass confirmatory and indicative features for the diagnosis of FRI; general treatment principles comprise risk stratification, patient optimization and a multidisciplinary team approach; surgical management and antimicrobial treatment.
The primary aim of the international consensus group is to improve patient outcome of FRI by disseminating these recommendations to the global community of healthcare providers and promoting the standardization of treatment principles and outcome measures. In the longer term, this standardization will also improve the comparability of future studies and trials. Further information is provided in the article ' Fracture-Related Infection: New Consensus on Diagnosis and Treatment' in this Innovations magazine.