Background: Vertebral artery injuries are often not diagnosed because they are asymptomatic. But there is information that up to 19% of all patients who incur trauma to the lower cervical spine have vertebral artery injuries. This incidence increase in flexion-distraction injuries. It is unclear as to the individual contribution of various force loads and resultant deformity on the etiology of these injuries. Purpose: To evaluate the degree of
Injuries of the cervical spine can be classified into six categories according to a mechanistic system describing the biomechanical deficiencies incurred in a cervical spine injury. However high velocity flexion compression loads cause multiple contiguous and noncontiguous fractures due to multiple force vectors. A universal classification system cannot be applied. Instability exists if there is greater than 3.5 mm of translation or greater than 11 degrees of angulation as compared to other segments. The degree of ligamentous injury on MRI correlates with instability in patients with lateral mass facet fractures, with rupture of multiple ligaments including the anterior longitudinal, posterior longitudinal, interspinous, or facet capsule. Patients with less than 13 mm of narrowing of the sagittal canal are predisposed to neurologic injury. Vertical compression injuries cause canal occlusion and vertebral column shortening. The timing of surgery in cases of spinal cord injury is controversial. There is no difference in outcome between early (<
72 hours) and late (>
5 days) surgery. However, there remains at least a theoretical benefit to early surgery. Compression-flexion injuries result in loss of the anterior column by compression followed by the posterior column in distraction. The injury is considered unstable if there is a vertical cleavage fracture of the vertebral body or displacement. Treatment includes a cervical orthosis or halo for minor injuries, depending on the degree of kyphosis. Major injuries with displacement should be treated surgically by anterior corpectomy and plate or an anterior/posterior fusion, depending on the degree of posterior instability. The most common level of vertical-compression injuries is at the C6 or C7 level. Minimally displaced injuries can be treated with a collar or halo. Fragmentation and peripheral displacement of the bony fragments needs a halo followed by surgery and this may include an anterior corpectomy and plating. Distraction-flexion injuries may result in facet sub-luxation with less than 25% displacement, or dislocation of one (UFD) or both (BFD) facet joints. When there is 3 mm of translation (25%), the canal is occluded 20–25%. With 6mm of translation (50%), there is 40–50% canal occlusion. MRI can help analyse the soft tissue and ligamentous injuries. In UFD, all posterior ligamentous structures including joint capsule, and half the disc annulus are disrupted. Disruption of ALL and PLL is not necessary to create a UFD. In addition to the posterior structures, the ALL, the PLL and disc are disrupted in BFD. Rupture of the intervertebral disc may include posterior herniation or circumferential disruption. All distraction flexion injuries should be reduced closed. The necessity of a preoperative MRI is undetermined. Preoperative MRI is recommended if there is an unreliable exam due to the patient being uncooperative, if there is neurological worsening with, or failure of closed reduction. If the patient is neurologically intact and closed reduction successful, a posterior cervical fusion is advocated if there is no evidence of an extruded disc on the post reduction MRI. If the closed reduction failed, or MRI indicated, and there is no evidence of a herniated disc, an open posterior reduction followed by fusion is performed. Anterior discectomy with reduction, a graft and a plate is performed for a herniated disc. Compression-extension injuries fail by compression of the posterior elements followed by distraction of the anterior elements. There are unilateral or bilateral fractures of the laminae/neural arch with degrees of displacement. Undisplaced neural arch fractures can be treated with a cervical orthosis or halo. Displaced neural arch fractures are treated with a posterior cervical fusion. There are two stages in the distraction-extension injury group. The anterior longitudinal ligament is disrupted with possibly a transverse fracture of the body. With more major injuries, there is a significant displacement injuring the posterior column. Stage 1 injuries can be treated with a halo and Stage 2 with an anterior decompression and fusion with a plating device. There are two stages to lateral flexion injuries. Minor injuries include asymmetric centrum fracture and a unilateral arch fracture. In addition, there is displacement of the body with contralateral ligamentous failure in major injuries. The treatment for Stage 1 is usually a collar while treatment for Stage 2 is usually a posterior cervical fusion. Posterior stabilization procedures may be performed with wires and cables with or without rods. Posterior clamps usually are not recommended; while plates and screws are preferred. The plates and screws are biomechanically superior to wiring and avoid canal penetration. They are ideal when there is loss of the posterior elements. Pedicle fixation should be considered when operating on the C2 or C7 level. One in five patients may have complete disruption of
Introduction: Oblique corpectomy is a surgical technique of spinal cord decompression through a limited bone resection of the postero lateral corner of the vertebral bodies. In this study the results of this technique applied in cases of spondylotic myelopathy and tumors are presented. Methods: The oblique corpectomy is achieved through a lateral approach with control and sometimes transposition of the VA. It can be used at any level from C2 to T1 and on as many levels as required from 1 to 5. It was mostly applied on cervical spondylotic myelopathy (N=157) or radiculopathy (N=89) but also on hourglass tumors (neurinomas N=67, meningiomas N=7, hemangioblastoma N=1, paraganglioma N=1) and different tumors N=49 involving the lateral part of the vertebral body such as osteoïd osteomas N=8, chordomas N=11, aneurysmal cyst N=3, sarcomas N=4. The total series includes 126 tumors. In most cases preservation of the main part of the vertebral bodies permitted to avoid bone grafting and plating. However stabilization procedure is still necessary when more than one disc are resected and when the discs are soft and not collapsed. Results: Excellent decompression was obtained in every case of spondylotic myelopathy and radiculopathy. Clinical results are similar to those obtained by any other techniques of decompression through anterior approach but without the complications related to grafting and plating. Improvement of the preoperative score was noted in 79% of patients with myelopathy stabilization in 13% and worsening in 8%. In patients with radiculopathy, good and excellent results were obtained in 85%. A better decompression of the intervertebral foramen is achieved through the oblique corpectomy since the whole length of the cervical nerve root from the dural sac to the
INTRODUCTION: Oblique corpectomy is a surgical technique of spinal cord decompression through a limited bone resection of the posterolateral corner of the vertebral bodies. In this study the results of this technique applied in cases of spondylotic myelopathy and tumours are presented. METHODS: The oblique corpectomy is achieved through a lateral approach with control and sometimes transposition of the VA. It can be used at any level from C2 to T1 and on as many levels as required from 1 to 5. It was mostly applied on cervical spondylotic myelopathy (N=157) or radiculopathy (N=89) but also on hourglass tumours (neurinomas N=67, meningiomas N=7, hemangioblastoma N=1, paraganglioma N=1) and different tumours N=49 involving the lateral part of the vertebral body such as osteoid osteomas N=8, chordomas N=11, aneurysmal cyst N=3, sarcomas N=4. The total series includes 126 tumours. In most cases preservation of the main part of the vertebral bodies permitted to avoid bone grafting and plating. However stabilisation procedure is still necessary when more than one disc is resected and when the discs are soft and not collapsed. RESULTS: Excellent decompression was obtained in every case of spondylotic myelopathy and radiculopathy. Clinical results are similar to those obtained by any other techniques of decompression through anterior approach but without the complications related to grafting and plating. Improvement of the pre-operative score was noted in 79% of patients with myelopathy stabilisation in 13% and worsening in 8%. In patients with radiculopathy, good and excellent results were obtained in 85%. A better decompression of the intervertebral foramen is achieved through the oblique corpectomy since the whole length of the cervical nerve root from the dural sac to the
To assess the outcome and safety of transarticular C1–C2 screw fixation. The clinical and radiological outcomes of 15 patients treated with posterior atlanto-axial transarticular screw fixation and posterior wiring was assessed at a minimum follow up of 6 months. Indications for fusion were rheumatoid arthritis in 8 (instability in 6 and secondary degenerative changes in 2), non-union odontoid fracture 4, symptomatic os-odontoideum one, C1–C2 arthrosis one and irreducible odontoid fracture one. Fusion was assessed with plain x-rays including flexion extension films. Twenty nine screws were placed under fluoroscopic guidance. Bilateral screws were placed in 14 patients and a single screw in one patient. This patient had a single screw placed due to the erosion of the contralateral C2 pars by an anomalous
To assess the outcome and safety of transarticular C1-C2 screw fixation. The clinical and radiological outcomes of 15 patients treated with posterior atlantoaxial transarticular screw fixation and posterior wiring was assessed at a minimum follow up of six months. Indications for fusion were rheumatoid arthritis in eight (instability in six and secondary degenerative changes in two), non union odontoid fracture four, symptomatic osodontoideum one, C1-C2 arthrosis one and irreducible odontoid fracture one. Fusion was assessed with plain x-rays including flexion – extension films. Twenty nine screws were placed under fluroscopic guidance. Bilateral screws were placed in 14 patients and a single screw in one patient. This patient had a single screw placed due to the erosion of the controlateral C2 pars by an anomolous
Atlanto-axial rotatory fixation (AARF) is uncommon and is usually associated with a history of trauma to the neck or an upper respiratory tract infection. In patients who present early, correction of the deformity with traction and orthoses has been reported. Owing to failure of reduction, patients presenting late (more than a month after the condition developed) have been treated with an in situ C1/C2 fusion. Follow-up of in situ fusions has shown both progression of the deformity and correction through compensatory mechanisms. Over a five-year period seven AARF patients (16%), ranging in age from 5 to 11 years, presented more than three months after injury. All patients had a ‘cock robin’ posture and were neurologically intact. In three patients the injury was sustained in a fall from a tree and in four it was due to a motor vehicle accident. Two patients sustained additional fractures. All patients had CT scans. In four patients MR scans and MR angiography were used to evaluate the pathology in the atlanto-axial complex, including the
Purpose: Upper cervical spine stabilization in children can be challenging due to anatomic abnormalities such as incomplete posterior elements,
Introduction and Aims: C1 lateral mass screw fixation offers a powerful alternative biomechanical fixaion for upper cervical disorders. The anatomical constraints to this fixation have not been described yet and are essential to ensure avoidance of neurovascular damage. Method: Fifty patients (including five patients with rheumatoid arthritis) underwent upper cervical CT scans. Analysis of these CT scans involved use of calibrated scan measurements to identify the midpoint of the posterior lateral mass, the dimensions of the lateral mass, the direction of optimum screw passage, the position of the vertebral foramen at C1 and the ideal entry point for lateral mass screw fixation. Results: The average length of screw within the lateral mass was 20mm with 13.5mm of screw not in bone, behind the lateral mass, but necessary to allow rod placement posteriorly adjacent to other fixation points. The safest entry point was directly beneath the medial edge of the lamina origin. The ideal direction of screw angulation is parallel with the posterior arch, in the saggital plane. This entry point was on average 8.8mm from the
Introduction: C1 lateral mass screw fixation offers a powerful alternative biomechanical fixation for upper cervical disorders. The anatomical constraints to this fixation have not been described yet and are essential to ensure avoidance of neurovascular damage. Methods: 50 patients (including 5 patients with rheumatoid arthritis) underwent upper cervical CT scans. Analysis of these CT scans involved use of calibrated scan measurements to identify the midpoint of the posterior lateral mass, the dimensions of the lateral mass, the direction of optimum screw passage, the position of the vertebral foramen at C1 and the ideal entry point for lateral mass screw fixation. Results: The average length of screw within the lateral mass was 20 mm with 13.5mm of screw not in bone, behind the lateral mass, but necessary to allow rod placement posteriorly adjacent to other fixation points. The safest entry point was directly beneath the medial edge of the lamina origin. The ideal direction of screw angulation is parallel with the posterior arch, in the saggital plane. This entrypoint was on average 8.8 mm from the
Background: A 9- year-old child with osteogenesis imperfecta and severe cervical kyphosis associated with wedged vertebrae and progressive neurological deterioration is presented. There is no report of upper cervical kyphosis associated with wedged vertebrae in osteogenesis imperfecta in the literature. We discuss the methods and difficulties in the surgical management of this condition and to highlight the appropriate surgical approach. Methods: Methods:A 9-year-old girl presented with progressive cervical kyphosis and quadriparesis. At the age of 3 years she underwent posterior cervical fusion (C1–C6) for instability and deformity. Radiological and laboratory investigations confirmed the diagnosis of osteogenesis imperfecta. Radiographs of the cervical spine revealed a kyphotic deformity of 120° Magnetic Resonance Imaging (MRI) and Computerised Tomography (CT) scans showed anterior cord compression due to wedged vertebrae at C3 and C4. MRI-Angiography was performed pre-operatively to identify the anatomical position of the
Objective:. To observe the incidence of intra-operative vascular injuries during anterior cervical decompression and fusion (ACDF). Secondly, management and monitoring of the outcome post vascular injury during ACDF. Methods:. This a prospective study. A review of all spinal patients' records was performed from June 2006 to April 2011. A comprehensive literature review was also utilized. Inclusion criteria – all patients had ACDF post trauma. All non-traumatic cases were excluded. Results:. The study consisted of 55 patients; 15 were females and 40 were males. The age distribution was 23–65 years. Two patients were excluded due to non-traumatic causes. Of the remaining 53 patients, four sustained intra-operative vascular injuries during ACDF surgery. All 4 patients had corpectomies, and one case was an iatrogenic injury. The commonly injured vessel during the ACDF surgery was the left
To describe a modification of the existing technique for C2 translaminar screw fixation that can be used for salvage in difficult cases. Bilateral crossing C2 laminar screws have recently become popular as an alternative technique for C2 fixation. This technique is particularly useful in patients with anomalous anatomy, as a salvage technique where other modes of fixation have failed or as a primary procedure. However, reported disadvantages of this technique include breach of the dorsal lamina and spinal canal, early hardware failure and difficulty in bone graft placement due to the position of the polyaxial screw heads. To address some of these issues, a modified technique is described. In this technique, the upper part of the spinous process of C2 is removed and the entry point of the screw is in the base of this removed spinous process. From October 2008 to March 2009, 6 patients underwent insertion of unilateral translaminar screws using our technique. The indications were: basilar invagination(three cases), C1/C2 fracture (two cases), tumour (one case). Age varied from 22 to 81 years (mean 48 years). All patients had post-operative x-ray and CT scan to assess position of the screws. Mean follow-up was 6 months. The screw position was satisfactory in all patients. There were no intraoperative or early postoperative complications. Our modification enables placement of bone graft on the C2 lamina and is also less likely to cause inadvertent cortical breach. Because of these advantages, it is especially suitable for patients with advanced rheumatoid arthritis with destruction of the lateral masses of C2 or as part of a hybrid construct in patients with unilateral high riding
Purpose of study. Transarticular screw fixation offers acceptably high fusion rates but is not possible in 18% of patients due to a high riding
Purpose: The purpose of the study is to access the efficacy of CT angiogram evaluation of the
The posterior midline approach used in spinal surgery has been associated with a significant rate of wound dehiscence. This study investigates anatomical study of the arterial supply of the cervical and thoracic spinal muscles and overlying skin at each vertebral level. It aimed to provide possible anatomical basis for such wound complications. A dissection and angiographic study was undertaken on 8 cadaveric neck and posterior torso from 6 embalmed and 2 fresh human cadavers. Harvested cadavers were warmed and hydrogen peroxide was injected into the major arteries. Lead oxide contrast mixture was injected in stepwise manner into the subclavian and posterior intercostal arteries of each specimen. Specimens were subsequently cross-sectioned at each vertebral level and bones elevated from the soft tissue. Radiographs were taken at each stage of this process and analysed. The cervical paraspinal muscles were supplied by the deep cervical arteries, transverse cervical
Introduction. To introduce a new classification method and analyze related risk factor about lateral wall perforation associated with lower cervical pedicle screw and free-hand insertion technique. Methods. A Retrospective study was made to analyze 214 patients (1024 screws) with various cervical spine disorders, involved in pedicle screw instrumentation at C3-7 from July 2004 to July 2009. Researchers assessed the position of the screws in the pedicle by carefully probing intraoperatively and studying postoperative thin-slice computed tomography scan. Perforation of lateral wall was classified into two phases. Phase I refers to the burst of the pedicle by screw, which means that the length of screw threads penetrating the external cortex of pedicles on CT scan is 2 mm, whereas in Phase, the length is >2 mm. The Penetrated screws and related factors were analyzed though Backward Stepwise (Wald) Logistic regression. Results. During the follow-up, 2 screws were reported to be broken and 1 screw loosened. Of the screws inserted, total of 129 screws 12.60% have shown violated of lateral pedicle walls, included 101 screws (9.86%) causative of Phase I and 28 screws (2.73%) of Phase II. Two variance were deduced in the regression analysis, which concerned to ratio variance between inner and lateral walls, PRC 0.695, OR value = 2.003and angle difference variance between screws implanted and measurements preoperativePRC −1.542, OR value = 0.214). Conclusions. Free-hand lower cervical pedicle screw insertion in this series was comparatively safety. Phase I Penetration was believed to be safe of
Objective: To review the clinical outcome of 37 consecutive patients undergoing C1– C2 transarticular fixation for patients with Rheumatoid Arthritis. Design: Prospective Observational Study. Methods: There were 37 patients at 2 centres. Age range was 37– 82 years. The time since diagnosis to treatment was 2– 23 years. Clinical presentation included suboccipital pain in 26/ 37 patients and neck pain in 29/37 patients. 22 patients had presented with myelopathy ( Ranawat grade II or III A). The preoperative imaging included Plain X Rays, CT scans and MRI scans. All patients underwent C1/ C2 transarticular screws ( Stealth guided) except 4 patients in which an aberrant course of the
Introduction: The efficacy and complications of the transarticular screw procedure have been reported by many authors. However, few have reported this procedure for child younger than 10 years old. We have treated two children for atlantoaxial subluxation with transarticular screws, using a soft collar without a halo-vest, and have achieved bone union in good reduced position. Methods/results. Case 1: a 5-year-old boy with mental retardation and cerebellar infarction due to an insufficiency of the
Neck pain can be caused by pressure on the spinal cord or nerve roots from bone or disc impingement. This can be treated by surgically decompressing the cervical spine, which involves excising the bone or disc that is impinging on the nerves or widening the spinal canal or neural foramen. Conventional practise is to fuse the adjacent intervertebral joint after surgery to prevent intervertebral motion and subsequent recompression of the spinal cord or nerve root. However fusion procedures cause physiological stress transfer to adjacent segments which may cause Adjacent Segment Degeneration (ASD), a rapid degeneration of the adjacent discs due to increased stress. ASD is more likely to occur in fusions of two or more levels than single level fusions and is more common where there is existing degeneration of the adjacent discs, which is not unusual in people over 30 years of age. Partial dynamic stabilisation, which generally involves a semi-rigid spinal fixation, allows a controlled amount of intervertebral motion (less than physiological, but more than fusion) to prevent increased stress on the adjacent segments (potentially preventing ASD) whilst still preventing neural recompression. Partial dynamic stabilisation is suitable for treating spinal instability after decompression as well as certain degenerative instabilities and chronic pain syndromes. Dynamic stabilisation and semi-rigid fixation systems for the spine are typically fixated posteriorly. However, choice of posterior surgical stabilisation techniques in the cervical spine is limited due to the size of the osseous material available for fixation and the close proximity of the neural structures and the