The role of imaging in the pre- and postoperative evaluation of posterior occipito-cervical fusion (original) (raw)
Related papers
Occipitocervical Fixation: Long-Term Results
Spine, 2005
The study is a retrospective review of 58 patients who underwent occipitocervical fusion between 1997 and 2001. Objectives. Our objective is to study the clinical results after occipitocervical fixation with long-term follow-up and assess factors contributing to clinical success. Methods. Data from patient charts, operative notes, physician office notes, and imaging studies were incorporated in the study. Myelopathy was assessed using a Nurick scale for preoperative and postoperative evaluation. Fusion was assessed using cervical plane films with flexion and extension views. Results. Mean follow-up was 36 months, with all patients having a greater than 1-year follow-up. The most common pathology was congenital cranial settling (41%) followed by trauma (22%) and rheumatoid arthritis (17%). Myelopathy was the most common presentation (62%) followed by pain (28%). A successful fusion occurred in 48 out of 51 patients (94%). Symptoms improved in 86% of patients, whereas 35% improved 1 Nurick grade. Complications occurred in 30% of patients. The cervical wound infection rate was 5%. The rate of adjacent level degeneration was 7%. The mortality rate was 1.7%. Conclusions. Occipitocervical instrumentation allows for very high fusion rates without the need for halo vest immobilization. All patients with successful fixation have pain resolution. Myelopathy improves in most patients, whereas one-third of patients demonstrate dramatic improvement.
Biomechanical evaluation of occipitocervicothoracic fusion: impact of partial or sequential fixation
The spine journal : official journal of the North American Spine Society
Surgical instrumentation used for posterior craniocervical instability has evolved from simple wiring techniques to sophisticated implant systems that incorporate multiple means of rigid fixation for the cervical spine. Polyaxial screws and lamina hooks in conjunction with occipital plating and transitional rods for caudal fixation theoretically allow for fixation points at each vertebra along the posterior aspect of the cervical spine. However, the potential for anatomical constraints to prevent intraoperative instrumentation at the desired vertebral level exists. The biomechanical implications of such "skipped segments" have not been well documented. The purpose of this study was to determine the biomechanical effects of partial three-point fixation versus sequential fixation at all levels of the cervical spine from the occiput to T1. Fresh frozen human cadaveric cervical spines from the occiput (CO) to T1 were prepared and mounted on a spine simulator. Motion was assess...
The cervical end of an occipitocervical fusion: a biomechanical evaluation of 3 constructs
Journal of Neurosurgery: Spine, 2008
Object Stabilization with rigid screw/rod fixation is the treatment of choice for craniocervical disorders requiring operative stabilization. The authors compare the relative immediate stiffness for occipital plate fixation in concordance with transarticular screw fixation (TASF), C-1 lateral mass and C-2 pars screw (C1L-C2P), and C-1 lateral mass and C-2 laminar screw (C1L-C2L) constructs, with and without a cross-link. Methods Ten intact human cadaveric spines (Oc–C4) were prepared and mounted in a 7-axis spine simulator. Each specimen was precycled and then tested in the intact state for flexion/extension, lateral bending, and axial rotation. Motion was tracked using the OptoTRAK 3D tracking system. The specimens were then destabilized and instrumented with an occipital plate and TASF. The spine was tested with and without the addition of a cross-link. The C1L-C2P and C1L-C2L constructs were similarly tested. Results All constructs demonstrated a significant increase in stiffness...
Surgical Neurology International, 2014
Background: Occipital-cervical fusion (OCF) has been used to treat instability of the occipito-cervical junction and to provide biomechanical stability after decompressive surgery. The specific areas that require detailed morphologic knowledge to prevent technical failures are the thickness of the occipital bone and diameter of the C2 pedicle, as the occipital midline bone and the C2 pedicle have structurally the strongest bone to provide the biomechanical purchase for cranio-cervical instrumentation. The aim of this study was to perform a quantitative morphometric analysis using computed tomography (CT) to determine the variability of the occipital bone thickness and C2 pedicle thickness to optimize screw placement for OCF in a South East Asian population. Methods: Thirty patients undergoing cranio-cervical junction instrumentation during the period 2008-2010 were included. The thickness of the occipital bone and the length and diameter of the C2 pedicle were measured based on CT. Results: The thickest point on the occipital bone was in the midline with a maximum thickness below the external occipital protuberance of 16.2 mm (±3.0 mm), which was thicker than in the Western population. The average C2 pedicle diameter was 5.3 mm (±2.0 mm). This was smaller than Western population pedicle diameters. The average length of the both pedicles to the midpoint of the C2 vertebral body was 23.5 mm (±3.3 mm on the left and ±2.3 mm on the right). Conclusions: The results of this first study in the South East Asian population should help guide and improve the safety in occipito-cervical region instrumentation. Thus reducing the risk of technical failures and neuro-vascular injury.
Occipitocervical Fusion Surgery: Review of Operative Techniques and Results
Journal of Neurological Surgery Part B: Skull Base, 2015
Objective Varying types of clinicoradiologic presentations at the craniovertebral junction (CVJ) influence the decision process for occipitocervical fusion (OCF) surgery. We discuss the operative techniques and decision-making process in OCF surgery based on our clinical experience and a literature review. Material and Methods A total of 49 consecutive patients who underwent OCF participated in the study. Sagittal computed tomography images were used to illustrate and measure radiologic parameters. We measured Wackenheim clivus baseline (WCB), clivus-canal angle (CCA), atlantodental distance (ADD), and Powers ratio (PR) in all the patients. Results Clinical improvement on Nurick grading was recorded in 36 patients. Patients with better preoperative status (Nurick grades 1-3) had better functional outcomes after the surgery (p ¼ 0.077). Restoration of WCB, CCA, ADD, and PR parameters following the surgery was noted in 39.2%, 34.6%, 77.4%, and 63.3% of the patients, respectively. Complications included deep wound infections (n ¼ 2), pseudoarthrosis (n ¼ 2), and deaths (n ¼ 4). Conclusion Conventional wire-based constructs are superseded by more rigid screwbased designs. Odontoidectomy is associated with a high incidence of perioperative complications. The advent of newer implants and reduction techniques around the CVJ has obviated the need for this procedure in most patients.
Surgical outcome of Occipitocervical Fixation for Craniocervical Instability
Journal of Saidu Medical College, Swat, 2022
Background: The occipitocervical junction is a unique area between the cranium and the upper cervical spine. Treating pathologies of this region require a good knowledge and understanding of the anatomy, biomechanics of this region and nature of the disease. Objective: To evaluate the efficacy of Occipitocervical Fixation (OCF) in patients with craniocervical instability in two tertiary care hospitals. Metrial and Methods: This study was conducted at Combined Military Hospital Rawalpindi and Hayatabad Medical Complex, Peshawar from April 2005 to December 2016. All patients with craniocervical instability were included in our study, and those having occipital bone fractures or previously operated patients with same technique were excluded from this study. The patients were compared using lateral static and dynamic X-ray taken before the operation, after the operation, and during last follow-up. The Nurick score was used to assess neurological function pre and postoperatively. Results...
European Spine Journal, 2013
Introduction Surgical management of upper cervical spine (UCS) unstable injuries may be challenging as the number of cases requiring this surgery collected in every single center is small. This retrospective study was conducted to analyze the radiographic and clinical results in 12 patients undergoing a posterior occipito-cervical fusion by a polyaxial screws-rod-plate system. Methods There were eight male and four female patients with a mean age of 73.7 years (range 32-89 years). Six patients presented neurologic deficits at admission. Six patients had sustained major trauma. The remaining six patients had suffered a minor trauma. Results Two patients died postoperatively in Intensive Care Unit. All surviving patients achieved solid fusion at 6 months. No surviving patient had neurological deterioration postoperatively. There were no instrumentation failures or revision required. Two patients suffered from superficial occipital wound infection. Conclusions Although the indication to occipito-cervical fusion decreased since the new C1-C2 posterior fixation techniques were described, it remains a valid and reliable option in UCS post-traumatic instability to be applied even in emergency especially in the elderly.
European Spine Journal, 2001
The authors report on 32 consecutive patients with instability at the craniocervical, cervical and cervicothoracic regions suffering from various pathologies, who were treated with posterior instrumentation and fusion using the posterior hooks-rods-plate cervical compact Cotrel-Dubousset (CCD) instrumentation alone or, in three patients, in combination with anterior operation. The patients were observed postoperatively for an average of 31 months (range 25-44 months) and evaluated both clinically and radiographically using the following parameters: spine anatomy and reconstruction, sagittal profile, neurologic status, functional level, complications and status of arthrodesis. All patients but one (who died) achieved a solid arthrodesis based on plain and flexion/extension roentgenograms. Cervical lordosis (skull-C7) and cervicothoracic kyphosis (C7-T2) was improved by instrumentation towards a physiological lateral curve by an average of 33% (P<0.05) and 28% (P<0.05) respectively. Anterior vertebral olisthesis was reduced in the craniocervical and cervicothoracic region, by 73% and 90% respectively. At final follow-up there was an improvement of the neurologic Frankel status by an average of 1.2 grades and of myelo-
Egyptian Spine Journal
Background Data: Occipitocervical junction instability has always been a challenging surgical problem owing to the unique anatomical and biomechanical characteristics of this region. Purpose: To detect the safety, efficacy and related complications using polyaxial screw-based constructs with rod / plate system for occipitocervical instability. Study design: This is a retrospective study for 14 patients underwent occipitocervical fusion for instability using polyaxial screw-based constructs with rod / plate system during the period from
Advances in Orthopedics
Background. Despite the research progress in the thoraco-lumbo-pelvic balance, cervical spine balance has only recently gained increasing interest. To our knowledge, there is a lack of research regarding sagittal occipitocervical spine balance restoration following posterior occipitocervical fusion (POCF). Purpose. The primary outcome measure is the evaluation of sagittal cervical alignment roentgenographic parameters and the secondary is the functional outcome (NDI), following POCF for upper (C1 & C2) cervical trauma (UCT) in coexistence with upper cervical spine degeneration. Patients and Methods. Twenty old and elderly patients aged 62 ± 12 years with evident upper cervical degeneration, who received POCF for upper C1 & C2 unstable cervical spine injuries, were included. C2-C7 lordosis, C2-C7 SVA, spinocranial angle (SCA), T1-slope, neck tilt (NT), thorax inlet angle (TIA), cervical tilt (CT), cranial tilt (CrT), and C0-C1 angle were measured. The subfusion angle was used to stud...