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BMC Musculoskeletal Disorders Dec 2021Providing a stable osteosynthesis in fragility fractures of the pelvis can be challenging. Cement augmentation increases screw fixation in osteoporotic bone. Generating...
Is cement-augmented sacroiliac screw fixation with partially threaded screws superior to that with fully threaded screws concerning compression and pull-out force in fragility fractures of the sacrum? - a biomechanical analysis.
BACKGROUND
Providing a stable osteosynthesis in fragility fractures of the pelvis can be challenging. Cement augmentation increases screw fixation in osteoporotic bone. Generating interfragmentary compression by using a lag screw also improves the stability. However, it is not known if interfragmentary compression can be achieved in osteoporotic sacral bone by cement augmentation of lag screws. The purpose of this study was to compare cement-augmented sacroiliac screw osteosynthesis using partially versus fully threaded screws in osteoporotic hemipelvises concerning compression of fracture gap and pull-out force.
METHODS
Nine fresh-frozen human cadaveric pelvises with osteoporosis were used. In all specimens, one side was treated with an augmented fully threaded screw (group A), and the other side with an augmented partially threaded screw (group B) after generating a vertical osteotomy on both sides of each sacrum. Afterwards, first a compression test with fracture gap measurement after tightening of the screws was performed, followed by an axial pull-out test measuring the maximum pull-out force of the screws.
RESULTS
The fracture gap was significantly wider in group A (mean: 1.90 mm; SD: 1.64) than in group B (mean: 0.91 mm; SD: 1.03; p = 0.028). Pull-out force was higher in group A (mean: 1696 N; SD: 1452) than in group B (mean: 1616 N; SD: 824), but this difference was not statistically significant (p = 0.767).
CONCLUSIONS
Cement augmentation of partially threaded screws in sacroiliac screw fixation allows narrowing of the fracture gap even in osteoporotic bone, while resistance against pull-out force is not significantly lower in partially threaded screws compared to fully threaded screws.
Topics: Biomechanical Phenomena; Bone Cements; Bone Screws; Humans; Pelvis; Sacrum
PubMed: 34893059
DOI: 10.1186/s12891-021-04933-y -
The Journal of the American Academy of... Jan 2012Posterior pelvic percutaneous fixation following either closed or open reduction is a popular procedure. Knowledge of the posterior pelvic anatomy, its variations, and... (Review)
Review
Posterior pelvic percutaneous fixation following either closed or open reduction is a popular procedure. Knowledge of the posterior pelvic anatomy, its variations, and related imaging is critical to performing reproducibly safe surgery. The dysmorphic sacrum has several key characteristics. The upper portion of the sacrum is relatively colinear with the iliac crests on the outlet radiographic view. Other characteristics include the presence of mammillary bodies (ie, underdeveloped transverse processes) at the sacral mid-alar area, anterior upper sacral foramina that are not circular, residual upper sacral disks, an acute alar slope oriented from cranial-posterior-central to caudal-anterior-lateral on the outlet and lateral views of the sacrum, a tongue-in-groove sacroiliac joint surface visualized on CT, and cortical indentation of the anterior ala on the inlet radiographic view. The surgeon must be knowledgeable about individual patient anatomy to ensure safe iliosacral screw placement.
Topics: Bone Screws; Fracture Fixation, Internal; Fractures, Bone; Humans; Ilium; Pelvic Bones; Radiography; Sacrum
PubMed: 22207514
DOI: 10.5435/JAAOS-20-01-008 -
Neuroimaging Clinics of North America Aug 2023Three-dimensional (3D) printing technology has proven to have many advantages in spine and sacrum surgery. 3D printing allows the manufacturing of life-size... (Review)
Review
Three-dimensional (3D) printing technology has proven to have many advantages in spine and sacrum surgery. 3D printing allows the manufacturing of life-size patient-specific anatomic and pathologic models to improve preoperative understanding of patient anatomy and pathology. Additionally, virtual surgical planning using medical computer-aided design software has enabled surgeons to create patient-specific surgical plans and simulate procedures in a virtual environment. This has resulted in reduced operative times, decreased complications, and improved patient outcomes. Combined with new surgical techniques, 3D-printed custom medical devices and instruments using titanium and biocompatible resins and polyamides have allowed innovative reconstructions.
Topics: Humans; Printing, Three-Dimensional; Computer-Aided Design; Sacrum; Neoplasms
PubMed: 37356866
DOI: 10.1016/j.nic.2023.05.001 -
The Journal of Bone and Joint Surgery.... Nov 1976The pattern of fracture-dislocation of the upper part of the sacrum is demonstrated in three patients. The fracture line followed the segmental form of the sacrum and...
The pattern of fracture-dislocation of the upper part of the sacrum is demonstrated in three patients. The fracture line followed the segmental form of the sacrum and was usually caused by a posterior force against the pelvis which had been locked by hip flexion and knee extension. Fractures of the lumbar transverse processes also occurred, presumably from avulsion by the quadratus lumborum muscle. The damage to the sacral plexus found in all three cases recovered after several months. Radiographs of the injury are difficult to obtain in severely injured patients but oblique views of the sacrum help to determine the extent of the forward dislocation.
Topics: Adult; Female; Fractures, Bone; Humans; Joint Dislocations; Male; Radiography; Sacrum
PubMed: 1018033
DOI: 10.1302/0301-620X.58B4.1018033 -
Urology Apr 2023Fluoroscopic guidance is a key tool used in combination with sensory and motor testing to ensure optimal sacral neuromodulation lead placement. The objectives of this... (Review)
Review
OBJECTIVES
Fluoroscopic guidance is a key tool used in combination with sensory and motor testing to ensure optimal sacral neuromodulation lead placement. The objectives of this video are to briefly review bony landmarks for fluoroscopic imaging and provide strategies to overcome common obstacles during fluoroscopic mapping for sacral neuromodulation lead placement.
METHODS
Our video is divided into 2 parts. First, we review anatomic landmarks in anterior-posterior (AP) fluoroscopic imaging for identification of the sacrum and the medial edge of the bilateral sacral foramina. We then provide a series of nonideal fluoroscopic images, explaining the cause of the difficult interpretation and strategies to overcome these obstacles. In the second half, we similarly review the identification of S3 and optimal needle angle trajectory during lateral fluoroscopic imaging. We again provide a series of nonideal imaging examples to highlight strategies for needle placement in difficult cases.
RESULTS
We provide an overview of normal fluoroscopic landmarks for both AP and lateral fluoroscopic imaging during sacral neuromodulation lead placement, along with a series of 6 nonideal examples. Strategies for overcoming barriers to identification of bony anatomy on fluoroscopy are provided in the context of these examples.
CONCLUSION
While appropriate patient preparation and positioning are important to optimize fluoroscopic guidance during sacral neuromodulation lead placement, patient anatomy and other factors often obscure or distort expected anatomic landmarks. We demonstrate our approach to overcoming common fluoroscopic obstacles and provide strategies for improvement of operative efficiency. These strategies can be combined with other intraoperative information such as tactile feedback, additional fluoroscopic views, and intraoperative complex nerve mapping to help optimize sacral neuromodulation lead placement and improve operative efficiency.
Topics: Humans; Sacrum; Pelvis; Tomography, X-Ray Computed; Fluoroscopy; Electric Stimulation Therapy
PubMed: 36638971
DOI: 10.1016/j.urology.2022.12.029 -
Injury Oct 2021Iliosacral screw removal is an infrequent surgery, and when needed, removal of the washer can be surprisingly difficult. Different forceps, clamps and other non-specific...
Iliosacral screw removal is an infrequent surgery, and when needed, removal of the washer can be surprisingly difficult. Different forceps, clamps and other non-specific instruments are frequently used to this end, many a time without success, or at the expense of tissue damage, blood loss and radiation exposure. After trying all the tricks in the book, we devised this neat little surgical tactic that ensures easy and reliable retrieval of the washer when removing iliosacral screws percutaneously, with no increased morbidity.
Topics: Bone Screws; Fracture Fixation, Internal; Humans; Ilium; Radiation Exposure; Sacrum
PubMed: 34281696
DOI: 10.1016/j.injury.2021.06.038 -
Journal of Neurointerventional Surgery Sep 2013
Topics: Female; Humans; Male; Osteoporosis; Sacrum; Vertebroplasty
PubMed: 22753269
DOI: 10.1136/neurintsurg-2012-010434 -
Pediatric Radiology Aug 2004There are relatively few reports of sacral stress fractures in children. In adolescents, sacral stress fractures have been reported in patients involved in vigorous...
There are relatively few reports of sacral stress fractures in children. In adolescents, sacral stress fractures have been reported in patients involved in vigorous athletic activity. Recognition of these fractures is important to avoid unnecessary biopsy if the findings are confused with tumor or infection. We report a sacral fatigue fracture in a 15-year-old without a history of athletic participation or trauma.
Topics: Adolescent; Diagnosis, Differential; Female; Fractures, Stress; Humans; Low Back Pain; Magnetic Resonance Imaging; Sacrum; Tomography, Emission-Computed
PubMed: 15221238
DOI: 10.1007/s00247-004-1234-4 -
European Spine Journal : Official... May 2018To review the current literature on methods of accurate numeration of vertebral segments in patients with Lumbosacral transitional vertebrae (LSTVs). LSTVs are a common... (Review)
Review
PURPOSE
To review the current literature on methods of accurate numeration of vertebral segments in patients with Lumbosacral transitional vertebrae (LSTVs). LSTVs are a common congenital anomaly of the L5-S1 junction. While their clinical significance has been debated, unquestionable is the need for their identification prior to spinal surgery. We hypothesize that there are no reliable landmarks by which we can accurately number transitional vertebrae, and thus a full spinal radiograph is required.
METHODS
A Pubmed and EMBASE search using various combinations of specific key words including "LSTV", "lumbosacral transitional vertebrae", "count", "vertebral numbering", and "number" was performed.
RESULTS
The gold standard for spinal segment numeration in patients with LSTV remains whole spine imaging and counting caudally, starting from C2. If whole spine imaging is not available, the use of the iliac crest tangent sign on coronal magnetic resonance imaging (MRI) has fairly reliable sensitivity and specificity (81 and 64-88%, respectively) for accurate numeration of LSTV. The role of paraspinal anatomic markers such as the right renal artery, superior mesenteric artery, aortic bifurcation, and conus medullaris, for identification of vertebral levels is unreliable and should not be used.
CONCLUSIONS
A sagittal whole spine view should be added as a scout view when patients obtain lumbar MRI to standardize the vertebral numbering technique. To date, there has been no other method for accurate numeration of a transitional vertebral segment, other than counting caudally from C2. These slides can be retrieved under Electronic Supplementary Material.
Topics: Anatomic Landmarks; Humans; Lumbar Vertebrae; Magnetic Resonance Imaging; Sacrum
PubMed: 29564611
DOI: 10.1007/s00586-018-5554-8 -
Radiology Oct 1973
Topics: Adult; Diagnosis, Differential; Female; Humans; Lumbar Vertebrae; Male; Meningocele; Middle Aged; Sacrum; Tomography, X-Ray
PubMed: 4783126
DOI: 10.1148/109.1.49