Recent trends, technical concepts and components of computer-assisted orthopedic surgery systems: A comprehensive review

Computer-assisted orthopedic surgery (CAOS) systems have become one of the most important and challenging types of system in clinical orthopedics, as they enable precise treatment of musculoskeletal diseases, employing modern clinical navigation systems and surgical tools. This paper brings a comprehensive review of recent trends and possibilities of CAOS systems. There are three types of the surgical planning systems, including: systems based on the volumetric images (computer tomography (CT), magnetic resonance imaging (MRI) or ultrasound images), further systems utilize either 2D or 3D fluoroscopic images, and the last one utilizes the kinetic information about the joints and morphological information about the target bones. This complex review is focused on three fundamental aspects of CAOS systems: their essential components, types of CAOS systems, and mechanical tools used in CAOS systems. In this review, we also outline the possibilities for using ultrasound computer-assisted orthopedic surgery (UCAOS) systems as an alternative to conventionally used CAOS systems.Web of Science1923art. no. 519

Clinical and radiological aspects of traumatic pelvic ring injury

Epidemiological data regarding High-Energy Traumatic Pelvic Ring Injury in Sweden was missing. Further, there was no data regarding current knowledge and level of experience of Swedish first line trauma officers about the management of traumatic pelvic ring injury. While conventional X-ray has been widely criticized as an optimal tool in assessment of pelvic ring injuries, a practical substitute has not been proposed. We planned to study epidemiological aspects of High Energy Traumatic Pelvic Ring Injury using data from the Karolinska Trauma Center. To assess first line trauma medical officer’s knowledge and level of experience regarding acute management of pelvic trauma. To investigate alternative practical options instead of conventional X-ray during the treatment of pelvic fractures. We used data from the Swedish National Trauma Registry (SweTrau). We used the Karolinska University Hospital´s Patient Notes and PACS. We used a questionnaire in order to assess Swedish trauma unit’s medical officers about acute management of pelvic trauma. We further used three dimensional models for image fusion and motion analysis in order to investigate symmetry of human pelvis and to investigate a pelvic fracture model. We found that the incidence of High Energy Traumatic Pelvic Ring Injury was about 3.5/100 000 inhabitants per year in Stockholm. The 30-day mortality was 7.8% and the 1 year mortality was 9%. The main cause of mortality was traumatic brain injury. Intentional injuries had a mortality rate of 15%. The reoperation frequency was 22%. Main cause of reoperation was due to metalwork problems, and a majority of them were potentially avoidable. We found that a majority of the Swedish first line trauma officers were aware of presence of a pelvic binder in their department and knew how to apply it, while there was more experience in the university hospitals. There was a general misconception regarding limitation of pelvic binders as 55% believed that a pelvic binder can stop an arterial bleeding. We were further able to show that human hemi pelvises are symmetrical and the 3D images of the contralateral hemi pelvis can be used for pre-operative templating. We were able to show that using fusion of serial 3D images of a pelvic model, translations of ±0.2 mm and rotations of ±0.2° could be detected. We can hereby conclude that monitoring 30-day mortality seems enough while studying high energy pelvic injuries. Intentional injuries need further future studies as per high mortality rate. Reoperation frequency following fixation of disrupted high energy pelvic fractures is high and needs addressing and early detection. Limitations of pelvic binders should be addressed during the trauma courses. Low dose CT-scan together with serial image fusion can be a future substitute for conventional X-ray. Human hemi pelvises are symmetrical and the contralateral side can be used for templating

ADVANCED MOTION MODELS FOR RIGID AND DEFORMABLE REGISTRATION IN IMAGE-GUIDED INTERVENTIONS

Image-guided surgery (IGS) has been a major area of interest in recent decades that continues to transform surgical interventions and enable safer, less invasive procedures. In the preoperative contexts, diagnostic imaging, including computed tomography (CT) and magnetic resonance (MR) imaging, offers a basis for surgical planning (e.g., definition of target, adjacent anatomy, and the surgical path or trajectory to the target). At the intraoperative stage, such preoperative images and the associated planning information are registered to intraoperative coordinates via a navigation system to enable visualization of (tracked) instrumentation relative to preoperative images. A major limitation to such an approach is that motions during surgery, either rigid motions of bones manipulated during orthopaedic surgery or brain soft-tissue deformation in neurosurgery, are not captured, diminishing the accuracy of navigation systems. This dissertation seeks to use intraoperative images (e.g., x-ray fluoroscopy and cone-beam CT) to provide more up-to-date anatomical context that properly reflects the state of the patient during interventions to improve the performance of IGS. Advanced motion models for inter-modality image registration are developed to improve the accuracy of both preoperative planning and intraoperative guidance for applications in orthopaedic pelvic trauma surgery and minimally invasive intracranial neurosurgery. Image registration algorithms are developed with increasing complexity of motion that can be accommodated (single-body rigid, multi-body rigid, and deformable) and increasing complexity of registration models (statistical models, physics-based models, and deep learning-based models). For orthopaedic pelvic trauma surgery, the dissertation includes work encompassing: (i) a series of statistical models to model shape and pose variations of one or more pelvic bones and an atlas of trajectory annotations; (ii) frameworks for automatic segmentation via registration of the statistical models to preoperative CT and planning of fixation trajectories and dislocation / fracture reduction; and (iii) 3D-2D guidance using intraoperative fluoroscopy. For intracranial neurosurgery, the dissertation includes three inter-modality deformable registrations using physic-based Demons and deep learning models for CT-guided and CBCT-guided procedures

Open reduction and internal fixation versus casting for highly comminuted and intra-articular fractures of the distal radius (ORCHID): protocol for a randomized clinical multi-center trial

<p>Abstract</p> <p>Background</p> <p>Fractures of the distal radius represent the most common fracture in elderly patients, and often indicate the onset of symptomatic osteoporosis. A variety of treatment options is available, including closed reduction and plaster casting, K-wire-stabilization, external fixation and open reduction and internal fixation (ORIF) with volar locked plating. The latter is widely promoted by clinicians and hardware manufacturers. Closed reduction and cast stabilization for six weeks is a simple, convenient, and ubiquitously available intervention. In contrast, ORIF requires hospitalization, but allows for functional rehabilitation.</p> <p>Given the lack of randomized controlled trials, it remains unclear whether ORIF leads to better functional outcomes one year after injury than closed reduction and casting.</p> <p>Methods/Design</p> <p>ORCHID (Open reduction and internal fixation versus casting for highly comminuted intra-articular fractures of the distal radius) is a pragmatic, randomized, multi-center, clinical trial with two parallel treatment arms. It is planned to include 504 patients in 15 participating centers throughout Germany over a three-year period. Patients are allocated by a central web-based randomization tool.</p> <p>The primary objective is to determine differences in the Short Form 36 (SF-36) Physical Component Score (PCS) between volar locked plating and closed reduction and casting of intraarticular, comminuted distal radius fractures in patients > 65 years of age one year after the fracture. Secondary outcomes include differences in other SF-36 dimensions, the EuroQol-5D questionnaire, the Disability of the Arm, Shoulder, and Hand (DASH) instrument. Also, the range of motion in the affected wrist, activities of daily living, complications (including secondary ORIF and revision surgery), as well as serious adverse events will be assessed. Data obtained during the trial will be used for later health-economic evaluations. The trial architecture involves a central statistical unit, an independent monitoring institute, and a data safety monitoring board. Following approval by the institutional review boards of all participating centers, conduct and reporting will strictly adhere to national and international rules, regulations, and recommendations (e.g., Good Clinical Practice, data safety laws, and EQUATOR/CONSORT proposals)</p> <p>Discussion</p> <p>To our knowledge, ORCHID is the first multicenter RCT designed to assess quality of life and functional outcomes following operative treatment compared to conservative treatment of complex, intra-articular fractures of the distal radius in elderly patients. The results are expected to influence future treatment recommendations and policies on an international level.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN76120052">ISRCTN76120052</a></p> <p>Registration date: 31.07.2008; Randomization of first patient: 15.09.2008</p

Modified pedicle screw-rod fixation versus anterior pelvic external fixation for the management of anterior pelvic ring fractures: a comparative study

Background Anterior pelvic ring fracture, as high-energy trauma, needs to be effectively treated. The purpose of the current study was to evaluate the clinical applications of modified pedicle screw-rod fixation and anterior pelvic external fixation for the treatment of anterior pelvic ring fracture. Methods Either modified pedicle screw-rod fixation (modified PSRF group, N = 21) or anterior pelvic external fixation (APEF group, N = 22) was performed to 43 patients, with or without fixation of posterior ring. Clinical outcomes were evaluated via Majeed scores. Relevant clinical evaluation indicators including operation time, intraoperative blood loss, hospitalization duration, and complications were compared between these two groups. Results The operation time in APEF group was significantly less than that in modified PSRF group (P < 0.0001). No significant difference with respect to intraoperative blood loss and hospitalization duration between the two groups was shown (P = 0.51 and P = 0.33, respectively). Six patients developed surgical site infection in APEF group. Three patients experienced loss of fixation, and two patients experienced loosening of fixator in APEF group. Temporary lateral femoral cutaneous nerve irritation occurred in three patients in modified PSRF group while two patients in APEF group. One patient experienced femoral nerve palsy in modified PSRF group. Fractures of all patients healed well eventually. No statistical difference regarding Majeed evaluation scores was found between two groups. Conclusions Application of both modified PSRF and APEF could provide similar satisfactory clinical outcomes for anterior pelvic ring fracture. Modified PSRF, a minimally invasive technique with the advantages of internal fixation, could be performed as an alternative method for instable pelvic fractures