Imaging guidance using intraoperative CT (O-arm surgical imaging system) combined with a navigation system has been shown to increase accuracy in the placement of spinal instrumentation. The authors describe 4 complex upper cervical spine cases in which the O-arm combined with the StealthStation surgical navigation system was used to accurately place occipital screws, C-1 screws anteriorly and posteriorly, C-2 lateral mass screws, and pedicle screws in C-6. This combination was also used to navigate through complex bony anatomy altered by tumor growth and bony overgrowth. The 4 cases presented are: 1) a developmental deformity case in which the C-1 lateral mass was in the center of the cervical canal causing cord compression; 2) a case of odontoid compression of the spinal cord requiring an odontoidectomy in a patient with cerebral palsy; 3) a case of an en bloc resection of a C2–3 chordoma with instrumentation from the occiput to C-6 and placement of C-1 lateral mass screws anteriorly and posteriorly; and 4) a case of repeat surgery for a non-union at C1–2 with distortion of the anatomy and overgrowth of the bony structure at C-2.
Kern H. Guppy, Indro Chakrabarti and Amit Banerjee
Kern H. Guppy, Mark Hawk, Indro Chakrabarti and Amit Banerjee
The authors present 2 cases involving patients who presented with myelopathy. Magnetic resonance imaging of the cervical spine showed spinal cord signal changes on T2-weighted images without any spinal cord compression. Flexion-extension plain radiographs of the spine showed no instability. Dynamic MR imaging of the cervical spine, however, showed spinal cord compression on extension. Compression of the spinal cord was caused by dynamic anulus bulging and ligamentum flavum buckling. This report emphasizes the need for dynamic MR imaging of the cervical spine for evaluating spinal cord changes on neutral position MR imaging before further workup for other causes such as demyelinating disease.
Kern H. Guppy, James W. Silverthorn and Paul T. Akins
Intrathecal spinal catheters (lumbar drains) are indicated for several medical and surgical conditions. In neurosurgical procedures, they are used to reduce intracranial and intrathecal pressures by diverting CSF. They have also been placed for therapeutic access to administer drugs, and more recently, vascular surgeons have used them to improve spinal cord perfusion during the treatment of thoracic aortic aneurysms. Insertion of these lumbar drains is not without attendant complications. One complication is the shearing of the distal end of the catheter with a resultant retained fragment. The authors report the case of a 65-year-old man who presented with a subarachnoid hemorrhage due to the migration of a retained lumbar drain that sheared off during its removal. To the best of the authors' knowledge, this is the first case of rostral migration of a retained intrathecal catheter causing subarachnoid hemorrhage. The authors review the literature on retained intrathecal spinal catheters, and their findings support either early removal of easily accessible catheters or close monitoring with serial imaging.
Case report and review of the literature
Kern H. Guppy, Franklin Wagner, Rabih Tawk and Lisbeth Gallagher
✓ The authors present the rare case of a myxoma, a benign soft-tissue tumor of mesenchymal origin noted for occurring in the left atrium of the heart, which was found in the lumbar paraspinal muscles of an 80-year-old woman. This patient experienced low-back pain for over 20 years and had noted its increasing severity with the development of an L-5 radiculopathy over a 3-month period. Magnetic resonance imaging of the lumbar spine revealed a large paraspinal mass that invaded the L-5 vertebral body and the left foramen of L5—S1. A computerized tomography—guided biopsy sampling procedure was performed, and examination of the specimen revealed an intramuscular myxoma. The patient underwent resection of the tumor and nerve root decompression. The diagnosis of intramuscular myxoma was confirmed, and the patient experienced complete resolution of her presenting symptoms. This patient represents the third reported case (the first in the English-language literature) of an intramuscular (paraspinal) myxoma presenting with lumbar nerve root compression.
Kern H. Guppy, Indro Chakrabarti, Richard S. Isaacs and Jae H. Jun
En bloc resection of cervical chordomas has led to longer survival rates but has resulted in significant morbidities from the procedure, especially when the tumor is multilevel and located in the high-cervical (C1–3) region. To date, there have been only 5 reported cases of multilevel en bloc resection of chordomas in the high-cervical spine. In this technical report the authors describe a sixth case. A complete spondylectomy was performed at C-2 and C-3 with spinal reconstruction and stabilization, using several new modalities that were not used in the previous cases. The use of 1) preoperative endovascular sacrificing of the vertebral artery, 2) CT image-guidance, 3) an ultrasonic aspirator for skeletonizing the vertebral artery, and 4) the custom design of an anterior cage all contributed to absence of intraoperative or long-term (20 months) hardware failure and pseudarthrosis.
Kern H. Guppy, Jessica Harris, Jason Chen, Elizabeth W. Paxton and Johannes A. Bernbeck
Fusions across the cervicothoracic junction have been challenging because of the large biomechanical forces exerted resulting in frequent reoperations for nonunions. The objective of this study was to investigate a retrospective cohort using chart review of posterior cervicothoracic spine fusions with and without bone morphogenetic protein (BMP) and to determine the reoperation rates for symptomatic nonunions in both groups.
Between January 2009 and September 2013, posterior cervicothoracic spine fusion cases were identified from a large spine registry (Kaiser Permanente). Demographics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was used to estimate odds ratios and 95% confidence intervals. Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test.
In this cohort there were 450 patients (32.7% with BMP) with a median follow-up of 1.4 years (interquartile range [IQR] 0.5–2.7 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.088). In a subset of patients with more than 1 year of follow-up, 260 patients were identified (43.1% with BMP) with a median follow-up duration of 2.4 years (IQR 1.6–3.3 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervicothoracic fusions with and without BMP (0.0% vs 2.7%, respectively; p = 0.137) for more than 1 year of follow-up.
This study presents the largest series of patients using BMP in posterior cervicothoracic spine fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were 0% with BMP and 2.7% without BMP. No statistically significant difference in the reoperation rates for symptomatic nonunions with or without BMP was found.
Kern H. Guppy, Jessica Harris, Jason Chen, Elizabeth W. Paxton, Julie Alvarez and Johannes Bernbeck
Bone morphogenetic protein (BMP) was first approved in 2002 for use in single-level anterior lumbar fusions as an alternative to iliac crest grafts. Subsequent studies have concluded that BMP provides superior fusions rates and therefore reduces reoperations for nonunions. The purpose of this study was to determine the reoperation rates for symptomatic nonunions in posterior cervical (subaxial) spinal fusions with and without the use of BMP and to determine if the nonunion rates are statistically significantly different between the two groups.
Between January 2009 and September 2013, the authors identified 1158 posterior cervical spinal fusion cases in the subaxial spine (C2–7) from a large spine registry (Kaiser Permanente). Patient characteristics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was conducted to produce estimates of odds ratios (OR) and 95% confidence intervals (CIs). Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test.
In this cohort there were 1158 patients (19.3% with BMP) with a median follow up of 1.7 years (interquartile range [IQR] 0.7–2.9 years) and median duration to operative nonunion of 0.63 years (IQR 0.44–1.57 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.179). In a subset of patients with more than 1 year of follow-up, 788 patients were identified (22.5% with BMP) with a median follow-up duration of 2.5 years (IQR 1.7–3.4 years) and a median time to operative nonunion of 0.73 years (IQR 0.44–1.57 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervical (subaxial) fusions with BMP compared with non-BMP (1.1% vs 0.7%; crude OR 1.73, 95% CI 0.32–9.55, p = 0.527) for more than 1 year of follow-up.
This study presents the largest series of patients using BMP in posterior cervical (subaxial) spinal fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were found to be 1.1% with BMP and 0.7% without BMP. There was no significant difference in the reoperation rates for symptomatic nonunions with or without BMP.
Kern H. Guppy, Paul T. Akins, Gregory S. Moes and Michael D. Prados
Oligodendroglioma of the spinal cord is a rare tumor that most often presents with spinal cord symptoms. The authors present a case of spinal cord oligodendroglioma that was associated with cerebral rather than spinal cord symptoms. A 30-year-old woman developed nausea, vomiting, and severe headaches. Magnetic resonance imaging of the brain showed meningeal enhancement. The patient underwent a craniotomy with biopsies of the meninges and brain. The biopsy findings revealed an abnormal arachnoid thickening without tumor cells. The patient later developed hydrocephalus and underwent shunt placement. Cerebrospinal fluid cytological findings were negative for tumor cells or infection. She was found to have a cervical cord lesion at C3–4 that was initially nonenhancing but later enhanced after Gd administration. Biopsy of the cord lesion with partial resection showed a WHO Grade II oligodendroglioma with 1p and 19q deletions determined by fluorescence in situ hybridization. Neurooncological treatment with tumor radiation and temozolomide (Temodor) resulted in improvement in radiographic findings, symptoms, and long-term survival. This paper presents an extensive review of the literature, which revealed only 2 other reported cases of cerebral symptoms in adults that preceded spinal cord symptoms in a patient with oligodendroglioma of the spinal cord. It is also the first reported case of oligodendrogliomatosis due to a cervical spinal cord oligodendroglioma with 1p and 19q deletions.