Abstract: Posterior cervical decompression and fusion (PCF) is a common surgical technique used to treat various cervical spine pathologies. However, there are various complications associated with PCF that can negatively impact patient outcome. We performed a comprehensive literature review to identify the most common complications following PCF using PubMed, Cochrane Database of Systematic Reviews, and Google Scholar. The overall complication rates of PCF are estimated to range from about 15% to 25% in the current literature. The most common immediate complications include acute blood loss anemia, surgical site infection (SSI), C5 palsy, and incidental durotomy; the most common long-term complications include adjacent segment degeneration, junctional kyphosis, and pseudoarthrosis. Three principal mechanisms are thought to contribute to complications. First, higher number of fusion levels, obesity, and more complex pathologies can increase the invasiveness of the planned procedure, thus increase complications. Second, wound healing and arthrodesis may be impaired due to poor blood flow due to various patient factors such as smoking, diabetes, increased frailty, steroid use, and other medical comorbidities. Finally, increased biomechanical stress on the upper instrumented vertebra (UIV) and lowest instrumented vertebra (LIV) may predispose patient to chronic degeneration and result in adjacent level degeneration and/or junctional problems. Reducing the modifiable risk factors pre-operatively can decrease the overall complication rate. Neurologic deficits may be reduced with adequate intraoperative decompression of neural elements. SSI may be reduced with meticulous wound closure that minimizes dead space, drain placement, and the use of intra-wound antibiotics. Careful design of the fusion construct with consideration in spinal alignment and biomechanics can help to reduce the rate of junctional problems. Spine surgeons should be aware of these complications associated with PCF and the corresponding prevention strategies optimize patient outcomes.
We demonstrate the setup and workflow of performing robotic spine surgery using the Mazor XTM system (MAZOR Robotics Inc, Orlando, Florida) in this video. An illustrative case was presented, including detailed steps for S2AI screw and lumbar pedicle screw placement using robotic assistance. A step-by-step narration is provided along with discussion of surgical nuances. Robotic spine surgery can be a safe and efficient method for screw placement, which can potentially reduce the risk of screw malposition. Spine surgeons should be familiar with this technology and keep this technique in their armamentarium. There is no identifying information in this video. A patient consent was obtained for publishing of the material included in the video.
The S2-alar-iliac (S2AI) screw is an increasingly popular method for spinopelvic fixation. The technique of freehand S2AI screw placement has been recently described. The purpose of this study was to demonstrate, through a CT imaging study of patients with spinal deformity, that screw trajectories based on the posterior superior iliac spine (PSIS) and sacral laminar slope result in reliable freehand S2AI trajectories that traverse safely above the sciatic notch.Fifty consecutive patients (age ≥ 18 years) who underwent primary spinal deformity surgery were included in the study. Simulated S2AI screw trajectories were analyzed with 3D visualization software. The cephalocaudal coordinate for the starting point was 15 mm cephalad to the PSIS. The mediolateral coordinate for the starting point was in line with the lateral border of the dorsal foramina. The cephalocaudal screw trajectory was perpendicular to the sacral laminar slope. Screw trajectories, lengths, and distance above the sciatic notch were measured.The mean sagittal screw angle (cephalocaudal angulation) was 44.0° ± 8.4° and the mean transverse angle (mediolateral angulation) was 37.3° ± 4.3°. The mean starting point was 5.9 ± 5.8 mm distal to the caudal border of the S1 foramen. The mean screw length was 99.9 ± 18.6 mm. Screw trajectories were on average 8.5 ± 4.3 mm above the sciatic notch. A total of 97 of 100 screws were placed above the sciatic notch. In patients with transitional lumbosacral anatomy, the starting point on the lumbarized/sacralized side was 3.4 mm higher than on the contralateral unaffected side.The PSIS and sacral laminar slope are two important anatomical landmarks for freehand S2AI screw placement.
A 26-year-old woman with prior T3–L4 spinal fusion for adolescent idiopathic scoliosis was incidentally found to have a malpositioned left T6 pedicle screw encroaching the descending thoracic aorta...
: Posterior cervical osteotomies are powerful techniques for the correction of rigid cervical deformity. These include a variety of subtypes including partial facet joint resection, complete facet joint resection, opening wedge osteotomy (OWO), and closing wedge osteotomy (CWO). The partial facet joint resection provides limited lordosis but can be applied across multiple levels and provides bony surface for fusion. Complete facet joint resection can also be performed across multiple segments for a cumulative effect and like the partial facet joint resection requires mobility of the anterior column. The OWO is traditionally performed at C7 and involves complete a complete laminectomy, facetectomy, and pediculectomy with special care to fully decompress the C8 nerve roots prior to osteotomy closure. The osteotomy utilizes a fulcrum of rotation in the middle column with shortening of the posterior column and lengthening of the anterior column with an osteoclastic fracture that must be performed with significant care. The CWO is similar to an OWO with the addition of an osteotomy into the vertebral body that is closed like a pedicle subtraction osteotomy (PSO). The goal of this review article is to summarize posterior osteotomy techniques for cervical deformity correction.
An accurate understanding of the morbidity and mortality associated with brain arteriovenous malformation (AVM) hemorrhage is important in determining the management of unruptured AVMs. Recent studies suggest this morbidity to be lower than assumed. We sought to perform a detailed critical assessment of the morbidity associated with ruptured brain AVMs.A retrospective chart review from a single-center tertiary care medical center was performed. Inclusion criteria were patients admitted with intracranial hemorrhage caused by a previously untreated AVM. Forty variables were analyzed including patient demographics, imaging findings, clinical course, and clinical examinations.From 2008 to 2013, of the 51 patients who fit our inclusion criteria, we found admission National Institutes of Health Stroke Scale (NIHSS) scores of 0, 1-9, and ≥10 in 22%, 24%, and 55%, respectively. Hematoma location was parenchymal in 33%, intraventricular in 10%, subarachnoid in 4%, and combined in 53%. Deep venous drainage was present in 35% of cases and associated aneurysms were present in 37%. 43% underwent emergency hematoma evacuation while four patients died during their admission. Of those who survived, 74% had neurologic deficits upon discharge (NIHSS ≥1), with 25.5% of patients having a severe deficit (NIHSS ≥10). On follow-up, 55% were independent in their daily activities of living.Our assessment of morbidity associated with brain AVM rupture is higher than previously assumed and reported. These results should be further validated in a larger, more representative sample. An accurate understanding of the morbidity associated with AVM rupture is important as more patients with unruptured brain AVMs seek consultation.