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European Spine Journal : Official... Jun 2006We report preliminary results for unstable sacral fractures treated with a modified posterior triangular osteosynthesis. Seven patients were admitted to our trauma...
We report preliminary results for unstable sacral fractures treated with a modified posterior triangular osteosynthesis. Seven patients were admitted to our trauma center with an unstable sacral fracture. The average age was 31 years (22-41). There were four vertical shear lesions of the pelvis and three transverse fracture of the upper sacrum. The vertical shear injuries were initially treated with an anterior external fixator inserted at the time of admission. Definitive surgery was performed at a mean time of 9 days after trauma. The operation consisted in a posterior fixation combining a vertebropelvic distraction osteosynthesis with pedicle screws and a rod system, whereby the transverse fixation was obtained using a 6 mm rod as a cross-link between the two main rods. Late displacement of the posterior pelvis or fracture was measured on X-ray films according to the criteria of Henderson. The patients were followed-up for a minimum time of 12 months. Four patients who presented with a pre-operative perineal neurological impairment made a complete recovery. No iatrogenic nerve injury was reported. One case of deep infection was managed successfully with surgical debridement and local antibiotics. All patients complained of symptoms related to the prominence of the iliac screws. The metalwork was removed in all cases after healing of the fracture, at a mean time of 4.3 months after surgery. No loss of reduction of fracture was seen at final radiological follow-up. The preliminary results are promising. The fixation is sufficiently stable to allow an immediate progressive weight-bearing, and safe nursing care in polytrauma cases. The only problem seems to be related to prominent heads of the distal screws.
Topics: Adult; Bone Screws; Female; Fracture Fixation, Internal; Humans; Male; Radiography; Sacrum; Spinal Fractures
PubMed: 15843970
DOI: 10.1007/s00586-004-0858-2 -
Postnatal maturation of the sacrum and coccyx: MR imaging, helical CT, and conventional radiography.AJR. American Journal of Roentgenology Apr 1998The purpose of this paper is to provide a detailed radiologic description of the postnatal developmental anatomy of the sacrum and coccyx as revealed by MR imaging,...
OBJECTIVE
The purpose of this paper is to provide a detailed radiologic description of the postnatal developmental anatomy of the sacrum and coccyx as revealed by MR imaging, helical CT, and conventional radiography.
MATERIALS AND METHODS
One hundred ten imaging examinations of the sacrococcygeal spine were performed in patients who were newborn to 30 years old. Imaging included conventional radiography (n = 63), three-dimensional gradient-recalled echo MR imaging (n = 10), and helical CT with sagittal and angled coronal reformations (n = 37). A detailed analysis was performed of the ossification and fusion of the primary and secondary ossification centers.
RESULTS
The sacrum and coccyx were noted to develop from 58 to 60 sacral ossification centers and eight coccygeal centers, respectively. These centers were noted to ossify and fuse in an organized temporal pattern from the fetal period to the age of 30.
CONCLUSION
The sacrum and coccyx are formed by a complex process that fuses primary and secondary ossification centers. Because the maturation process can be asymmetric, an understanding of this process may prove useful for distinguishing physeal plates from fracture lines.
Topics: Adolescent; Adult; Child; Child, Preschool; Coccyx; Female; Humans; Infant; Infant, Newborn; Magnetic Resonance Imaging; Male; Sacrum; Tomography, X-Ray Computed
PubMed: 9530059
DOI: 10.2214/ajr.170.4.9530059 -
Clinical Anatomy (New York, N.Y.) Mar 2011Lumbo-sacral fixation for the management of lumbo-sacral instability includes insertion of screws to the sacrum, most commonly into the posterior aspect of the pedicles...
Lumbo-sacral fixation for the management of lumbo-sacral instability includes insertion of screws to the sacrum, most commonly into the posterior aspect of the pedicles of the first sacralvertebra. This study was carried out to determine the normal anatomical parameters of the Egyptian sacrum, particularly of the first sacral vertebra and its pedicles, to find the safest approach for sacral screw placement in lumbo-sacral fixation procedures, and to describe racial characteristics, if any. In this study, 45 adult Egyptian dry sacra of unknown sex were used. Eleven sacral parameters were measured using the Vernier sliding caliper which is accurate to 0.1 millimeter. In this study, the sacrum showed a mean height of 11.43 ± 0.88 centimeters a mean width of 10.39 ± 0.91 centimeters with a mean sacral index of 90.82 ± 1.80 %. The first sacral pedicle had a mean anterior height of 1.83 ± 0.49 centimeters, a mean depth of 2.99 ± 0.53 centimeters and a mean posterior height of 2.38 ± 0.50 centimeters. A medialtrajectory path (representing an anteromedially-oriented first sacral pedicle screw) starting from the infero-lateral border of the S1 facet to the sacral promontory in the middle line was 5.23 ± 0.52 cm. The findings of the present study could provide accurate and specific parameters of the sacrum among Egyptians that could enhance the safety of insertion of sacral screws during lumbo-sacral fixation procedures upon Egyptian patients.
Topics: Bone Screws; Egypt; Humans; Joint Instability; Lumbar Vertebrae; Reproducibility of Results; Sacrum; Spinal Fusion
PubMed: 21322044
DOI: 10.1002/ca.21082 -
World Neurosurgery Jul 2019The middle cluneal nerves (MCNs) are stated to arise from the sacral dorsal rami of S1 to S3 and supply the gluteal skin, but their detailed anatomy is unclear and often...
OBJECTIVE
The middle cluneal nerves (MCNs) are stated to arise from the sacral dorsal rami of S1 to S3 and supply the gluteal skin, but their detailed anatomy is unclear and often variably depicted and described. Therefore, the goal of this study was to revisit the anatomy of the MCNs and provide a clearer picture of their morphology.
METHODS
Five fresh-frozen Caucasian cadavers (10 sides) (2 men and 3 women) were dissected for this study. The sacral dorsal rami from each posterior sacral foramen were identified and traced laterally to identify the MCNs. The contribution, pathway, and distribution of the MCNs were investigated.
RESULTS
Each sacral dorsal ramus joined to form the posterior sacrococcygeal plexus. A total of 25 MCNs were identified. The MCNs were formed by the sacral dorsal rami of S1-2 in 48% (12/25), S1-3 in 4% (1/25), S1-4 in 20% (5/25), S2-3 in 8% (2/25), and S2-4 in 20% (5/25). The MCNs pierced the gluteus maximus by 2 different pathways and supplied the gluteal skin or the gluteus maximus muscle.
CONCLUSIONS
We clarified the anatomy and variations of the MCNs and revisited its current nomenclature. Such knowledge might improve diagnoses and invasive procedure outcomes in patients with pathology in the region of the MCNs.
Topics: Aged; Aged, 80 and over; Cadaver; Female; Humans; Male; Pain; Sacrum; Spinal Nerves
PubMed: 31009778
DOI: 10.1016/j.wneu.2019.04.109 -
Clinical Biomechanics (Bristol, Avon) May 2019Bicortical screw fixation is an established technique to increase screw strength in vertebral bodies, although it is associated with several complications, for example... (Comparative Study)
Comparative Study
BACKGROUND
Bicortical screw fixation is an established technique to increase screw strength in vertebral bodies, although it is associated with several complications, for example screw-loosening. Cement augmentation can increase stability of screw-fixation but can also cause various complications, such as cement-leakage or cement embolism. In this study, we tested a new, multicortical screw fixation technique in the sacrum.
METHODS
Four fresh-frozen sacrums were used. In group 1, standard screw insertion, with sagittal parallel and axial convergent screw-drive was performed. In group 2, the screw-drive of the first screw was similar to the screw-drive in group 1. In addition, a second screw was inserted descending into the intended hole in the head of the screw and at a stable angle. Therefore, the screws of the multiloc humerus nail-system (Synthes) were used. The specimens were connected to a testing-machine and underwent cyclic axial loading with an increase in the load after each completed stage.
FINDINGS
Multicortical screw fixation leads to a significant increase in the number of completed cycles and a significantly increased load until failure.
INTERPRETATION
Multicortical screw fixation in the sacrum offers a stronger attachment of the screws. In the future, multicortical implants, which fulfil the criteria demanded in spine surgery, can offer higher stability and may decrease the loosening rates of the implanted screws.
Topics: Aged; Biomechanical Phenomena; Bone Cements; Bone Density; Bone Screws; Cadaver; Humans; Male; Prosthesis Design; Sacrococcygeal Region; Sacrum; Stress, Mechanical; Tomography, X-Ray Computed; Weight-Bearing
PubMed: 31005693
DOI: 10.1016/j.clinbiomech.2019.04.007 -
Journal of Orthopaedic Surgery and... Apr 2014In the literature, 'below and lateral to the superior S1 facet' is defined as the basic technique for screw introduction. Until a recently published modification, no... (Review)
Review
BACKGROUND
In the literature, 'below and lateral to the superior S1 facet' is defined as the basic technique for screw introduction. Until a recently published modification, no analysis for alternative starting point has been proposed nor evaluated, although some surgeons claim to use some modifications. In this study, we analyse the data from anatomical and radiological studies for optimal starting point in transpedicular S1 screw placement.
METHODS
A Medline search for key word combination: sacrum, anatomy, pedicle, screws and bone density resulted in 26 publications relevant to the topic. After a review of literature, two articles were chosen, as those including the appropriate set of data. The data retrieved from the articles is used for the analysis. The spatial relation of S1 facet, pedicles and vertebral body with cortical thickness and bone density in normal, osteopenic and osteoporotic sacrum is analysed.
RESULTS
Presented data advocates for more medial placement of the screws due to higher bone density and lower bone loss in osteoporosis. Medial shift of the starting point does not increase the risk of spinal canal perforation. Osteoarthritic changes within the facet can augment the posterior supporting point for screw. The facet angular orientation is similar to convergent screw trajectory.
CONCLUSIONS
Modified technique for S1 screw placement takes advantage of latest anatomical and clinical data. In our opinion, technique modification improves the reproducibility and may increase stability and the screws within the posterior cortex of the S1 vertebra. Further biomechanical and clinical study should be performed to prove its superiority to classical technique.
Topics: Bone Screws; Evidence-Based Medicine; Humans; Orthopedic Procedures; Radiography; Sacrum
PubMed: 24708681
DOI: 10.1186/1749-799X-9-22 -
Journal of Orthopaedic Trauma 1993A transforaminal fracture of the sacrum usually represents the posterior part of an unstable pelvic ring fracture and is associated with a high rate of neurological... (Comparative Study)
Comparative Study
A transforaminal fracture of the sacrum usually represents the posterior part of an unstable pelvic ring fracture and is associated with a high rate of neurological complications. Nerve root decompression combined with open reduction and internal fixation (ORIF) can be beneficial. Present fixation methods have the disadvantage of extensive bilateral posterior approaches and fixation across the sacroiliac joint. Three methods of internal fixation of the sacrum were compared in a biomechanical study using six fresh pelvic specimens. A fracture model consisting of a transforaminal osteotomy combined with a symphysis disruption in a single-leg stance was used. Standard Harrington sacral bars, an internal fixator, and a newly developed stabilization technique using adapted standard AO/ASIF small-fragment implants ("local osteosynthesis") were compared. Three-dimensional measurement of the fragment movement (goniometer system) showed a maximum displacement of 4.0-4.5 mm after maximal loading (990-1,181 N) and no differences among the implants. The failure load related to body weight was 85% for sacral bars, 74% for the local osteosynthesis, and 58% for the internal fixator. Major displacement under loading was observed in the direction of the foramen axis. The new osteosynthesis technique showed strength comparable to the clinically successfully applied method of stabilization with sacral bars. It adds the theoretical advantage of a minimized approach, without fixation and thus without involvement of the SI joints.
Topics: Biomechanical Phenomena; Body Weight; Fracture Fixation, Internal; Fractures, Bone; Humans; Prostheses and Implants; Sacrum
PubMed: 8459294
DOI: 10.1097/00005131-199304000-00002 -
Journal of Spinal Disorders Jun 1999Anatomical and biomechanical data have suggested that pedicle screw fixation at the sacrum is optimum in the anteromedial direction into the S1 vertebral body, yet the...
Anatomical and biomechanical data have suggested that pedicle screw fixation at the sacrum is optimum in the anteromedial direction into the S1 vertebral body, yet the possibility of posterior iliac crest interference with this screw pathway has been considered but not defined. This study aimed to determine if the anteromedial direction of screw placement into the vertebral body is possible in all cases at S1 and to assess the limiting effect of the posterior iliac crest. Computed tomography scans of the upper sacrum at the S1 pedicle parallel to the sacral endplate were examined in 100 patients. Analysis using a digitizer allowed characterization of an ideal screw pathway with variable screw and screw head diameters in an anteromedial direction into the S vertebral body. The effects of the posterior iliac crest upon these pathways were studied. The study demonstrated that anteromedial placement with bicortical fixation at the vertebral body was theoretically possible in almost all (98.5%) cases. Because the sacral body is often wider than the sacral spinal canal, a straight-ahead screw direction will often achieve placement into the S1 vertebral body, if the starting point for the screw allows screw placement adjacent to the medial border of the S1 pedicle with only 1.5 mm of cortical bone separating the canal and the screw. The space between the posterior iliac crest and the lateral aspect of the screw corridor ranges from a maximum of 52.4 mm to a minimum of 12.8, 6.2, and 0 mm for the 7-, 10-, and 12.5-mm screw corridors. On only three occasions (1.5%) was the ideal screw corridor not possible because of posterior iliac crest overlap. In each case, this occurred only unilaterally and when the widest of the screw corridors (12.5 mm) was used. Both the distance between the posterior iliac crests and the space available for optimum screw placement are greater in females than males.
Topics: Bone Screws; Female; Humans; Male; Radiography, Interventional; Sacrum; Spinal Fusion; Tomography, X-Ray Computed
PubMed: 10382776
DOI: No ID Found -
Der Unfallchirurg Jun 2008
Topics: Diagnosis, Differential; Fractures, Closed; Humans; Radiography; Sacrum; Spinal Fractures
PubMed: 18521558
DOI: 10.1007/s00113-008-1477-x -
Operative Orthopadie Und Traumatologie Dec 2021Rapid mobilization with full weight bearing by minimally invasive fixation of Os ilium to L5 in fractures of the sacrum and disruption of the sacroiliac joint (SIJ). (Review)
Review
OBJECTIVE
Rapid mobilization with full weight bearing by minimally invasive fixation of Os ilium to L5 in fractures of the sacrum and disruption of the sacroiliac joint (SIJ).
INDICATIONS
Unstable injuries of the posterior pelvic ring in fractures of the sacrum and disruption of the SIJ.
CONTRAINDICATIONS
Fracture of ilium and not injury related implants in the screw trajectory, neurological deficits regarding the fracture, decubitus in the area of surgical approach.
SURGICAL TECHNIQUE
Minimally invasive screw placement in the pedicles of L5, access of ilium screw via the posterior superior iliac spine. Radiological display for the iliacal screw bearing trajectory in Os Ilium as a drop-shaped/triangle canal. Insert a Jamshidi needle orthograde in the beam path, change to guide wire and placement of iliacal screw after resection of the bone in the screw head area. Submuscular insertion of the longitudinal rods, in case of double-sided instrumentation similar procedure on the opposite side, reduction of the fracture and fixation of the rods to screws.
POSTOPERATIVE MANAGEMENT
Postoperative mobilization with full weight bearing under physiotherapeutic guidance.
RESULTS
Patients treated with lumbopelvic stabilization in our facility between 2012 and 2017 were identified via the hospital database and retrospectively evaluated. In 24 patients with median age of 60.1 years and a follow-up-time of 11.8 months, we found no implant displacement, infection and no wound healing problems. Full weight bearing was permitted in 21 of 24 cases, in 3 cases partial load bearing due to other injuries. Three patients reported moderate mechanical irritation of iliacal screws; 1 patient reported severe irritability with removal of the implants after bony healing of fracture 1 year postoperatively.
Topics: Bone Screws; Fracture Fixation, Internal; Fractures, Bone; Humans; Middle Aged; Pelvic Bones; Retrospective Studies; Sacrum; Spinal Fractures; Treatment Outcome
PubMed: 34468791
DOI: 10.1007/s00064-021-00730-x