Pedicle versus lateral mass screws
Alexander R. Vaccaro
Risheng Xu, Daniel M. Sciubba, Ziya L. Gokaslan and Ali Bydon
Abnormal ossification of spinal ligaments is a well-known cause of myelopathy in East Asian populations, with ossification of the ligamentum flavum (OLF) and the posterior longitudinal ligament being the most prevalent. In Caucasian populations, OLF is rare, and there has been only 1 documented case of the disease affecting more than 5 spinal levels. In this report, the authors describe the clinical presentation, imaging characteristics, and management of the second published case of a Caucasian man with OLF affecting almost the entire thoracic spine. The literature is then reviewed with regard to OLF epidemiology, pathogenesis, presentation, and treatment.
Risheng Xu, Mohamad Bydon, Ziya L. Gokaslan, Jean-Paul Wolinsky, Timothy F. Witham and Ali Bydon
Epidural steroid injections are relatively safe procedures, although the risk of hemorrhagic complications in patients undergoing long-term anticoagulation therapy is higher. The American Society for Regional Anesthesia and Pain Medicine has specific guidelines for treatment of these patients when they undergo neuraxial anesthetic procedures. In this paper, the authors present a case in which the current American Society for Regional Anesthesia and Pain Medicine guidelines were strictly followed with respect to withholding and reintroducing warfarin and enoxaparin after an epidural steroid injection, but the patient nevertheless developed a spinal epidural hematoma requiring emergency surgical evacuation. The authors compare the case with the 8 other published cases of postinjection epidural hematomas in patients with coagulopathy, and the specific risk factors that may have contributed to the hemorrhagic complication in this patient is analyzed.
Scott L. Parker, Risheng Xu, Matthew J. McGirt, Timothy F. Witham, Donlin M. Long and Ali Bydon
The most common spinal procedure performed in the US is lumbar discectomy for disc herniation. Longterm disc degeneration and height loss occur in many patients after lumbar discectomy. The incidence of mechanical back pain following discectomy varies widely in the literature, and its associated health care costs are unknown. The authors set out to determine the incidence of and the health care costs associated with mechanical back pain attributed to segmental degeneration or instability at the level of a prior discectomy performed at their institution.
The authors retrospectively reviewed the data for 111 patients who underwent primary, single-level lumbar hemilaminotomy and discectomy for radiculopathy. All diagnostic modalities, conservative therapies, and operative treatments used for the management of postdiscectomy back pain were recorded. Institutional billing and accounting records were reviewed to determine the billed costs of all diagnostic and therapeutic measures.
At a mean follow-up of 37.3 months after primary discectomy, 75 patients (68%) experienced minimal to no back pain, 26 (23%) had moderate back pain requiring conservative treatment only, and 10 (9%) suffered severe back pain that required a subsequent fusion surgery at the site of the primary discectomy. The mean cost per patient for conservative treatment alone was $4696. The mean cost per patient for operative treatment was $42,554. The estimated cost of treatment for mechanical back pain associated with postoperative same-level degeneration or instability was $493,383 per 100 cases of first-time, single-level lumbar discectomy ($4934 per primary discectomy).
Postoperative mechanical back pain associated with same-level degeneration is not uncommon in patients undergoing single-level lumbar discectomy and is associated with substantial health care costs.
Andrew C. Vivas, Nir Shimony, Eric M. Jackson, Risheng Xu, George I. Jallo, Luis Rodriguez, Gerald F. Tuite and Carolyn M. Carey
Hydrocephalus associated with subdural hygromas is a rare complication after decompression of Chiari malformation type I (CM-I). There is no consensus for management of this complication. The authors present a series of 5 pediatric patients who underwent CM-I decompression with placement of a dural graft complicated by posterior fossa hygromas and hydrocephalus that were successfully managed nonoperatively.
A retrospective review over the last 5 years of patients who presented with hydrocephalus and subdural hygromas following foramen magnum decompression with placement of a dural graft for CM-I was conducted at 2 pediatric institutions. Their preoperative presentation, perioperative hospital course, and postoperative re-presentation are discussed with attention to their treatment regimen and ultimate outcome. In addition to reporting these cases, the authors discuss all similar cases found in their literature review.
Over the last 5 years, the authors have encountered 194 pediatric cases of CM-I decompression with duraplasty equally distributed at the 2 institutions. Of those cases, 5 pediatric patients with a delayed postoperative complication involving hydrocephalus and subdural hygromas were identified. The 5 patients were managed nonoperatively with acetazolamide and high-dose dexamethasone; dosages of both drugs were adjusted to the age and weight of each patient. All patients were symptom free at follow-up and exhibited resolution of their pathology on imaging. Thirteen similar pediatric cases and 17 adult cases were identified in the literature review. Most reported cases were treated with CSF diversion or reoperation. There were a total of 4 cases previously reported with successful nonoperative management. Of these cases, only 1 case was reported in the pediatric population.
De novo hydrocephalus, in association with subdural hygromas following CM-I decompression, is rare. This presentation suggests that these complications after posterior fossa decompression with duraplasty can be treated with nonoperative medical management, therefore obviating the need for CSF diversion or reoperation.
Mohamad Bydon, Risheng Xu, Kyriakos Papademetriou, Daniel M. Sciubba, Jean-Paul Wolinsky, Timothy F. Witham, Ziya L. Gokaslan, George Jallo and Ali Bydon
Unintended durotomies are a common complication of spine surgery and are often correlated with increased postoperative morbidity. Recently, ultrasonic bone curettes have been introduced in spine surgery as a possible alternative to the conventional high-speed drill, offering the potential for greater bone-cutting precision and less damage to surrounding soft tissues. To date, however, few studies have investigated the safety and efficacy of the ultrasonic bone curette in reducing the rates of incidental durotomy compared with the high-speed drill.
The authors retrospectively reviewed the records of 337 consecutive patients who underwent posterior cervical or thoracic decompression at a single institution between January 2009 and September 2011. Preoperative pathologies, the location and extent of spinal decompression, and the use of an ultrasonic bone curette versus the high-speed drill were noted. The rates of incidental durotomy, as well as hospital length of stay (LOS) and perioperative outcomes, were compared between patients who were treated using the ultrasonic bone curette and those treated using a high-speed drill.
Among 88 patients who were treated using an ultrasonic bone curette and 249 who were treated using a high-speed drill, 5 (5.7%) and 9 (3.6%) patients had an unintentional durotomy, respectively. This finding was not statistically significant (p = 0.40). No patients in either cohort experienced statistically higher rates of perioperative complications, although patients treated using an ultrasonic bone curette tended to have a longer hospital LOS. This difference may be attributed to the fact that this series contained a statistically higher number of metastatic tumor cases (p < 0.0001) in the ultrasonic bone curette cohort, likely increasing the LOS for that patient population. In 13 patients, the dural defect was repaired intraoperatively. No patients who experienced an incidental durotomy had new-onset or permanent neurological deficits postoperatively.
The safety and efficacy of ultrasonic bone curettes in spine surgery has not been well established. This study shows that the ultrasonic bone curette has a similar safety profile compared with the high-speed drill, although both are capable of causing iatrogenic dural tears during spine surgery.
Geoffrey P. Colby, Bowen Jiang, Matthew T. Bender, Narlin B. Beaty, Erick M. Westbroek, Risheng Xu, Li-Mei Lin, Jessica K. Campos, Rafael J. Tamargo, Judy Huang, Alan R. Cohen and Alexander L. Coon
Intracranial aneurysms in the pediatric population are rare entities. The authors recently treated a 9-month-old infant with a 19-mm recurrent, previously ruptured, and coil-embolized left middle cerebral artery (MCA) pseudoaneurysm, which was treated definitively with single-stage Pipeline-assisted coil embolization. The patient was 5 months old when she underwent resection of a left temporal Grade 1 desmoplastic infantile ganglioglioma at an outside institution, which was complicated by left MCA injury with a resultant 9-mm left M1 pseudoaneurysm. Within a month, the patient had two aneurysmal rupture events and underwent emergency craniectomy for decompression and evacuation of subdural hematoma. The pseudoaneurysm initially underwent coil embolization; however, follow-up MR angiography (MRA) revealed aneurysm recanalization with saccular enlargement to 19 mm. The patient underwent successful flow diversion–assisted coil embolization at 9 months of age. At 7 months after the procedure, follow-up MRA showed complete aneurysm occlusion without evidence of in-stent thrombosis or stenosis. Experience with flow diverters in the pediatric population is still in its early phases, with the youngest reported patient being 22 months old. In this paper the authors report the first case of such a technique in an infant, whom they believe to be the youngest patient to undergo cerebral flow diversion treatment.
Rafael De la Garza-Ramos, Risheng Xu, Seba Ramhmdani, Thomas Kosztowski, Mohamad Bydon, Daniel M. Sciubba, Jean-Paul Wolinsky, Timothy F. Witham, Ziya L. Gokaslan and Ali Bydon
The purpose of this study was to report the long-term clinical outcomes following 3- and 4-level anterior cervical discectomy and fusion (ACDF).
A retrospective review of all adult neurosurgical patients undergoing elective ACDF for degenerative disease at a single institution between 1996 and 2013 was performed. Patients who underwent first-time 3- or 4-level ACDF were included; patients with previous cervical spine surgery, those undergoing anterior/posterior approaches, and those with corpectomy were excluded. Outcome measures included perioperative complication rates, fusion rates, need for revision surgery, Nurick Scores, Odom's criteria, symptom resolution, neck visual analog scale (VAS) pain score, and persistent narcotics usage.
Seventy-one patients who underwent 3-level ACDF and 26 patients who underwent 4-level ACDF were identified and followed for an average of 7.6 ± 4.2 years. There was 1 case (3.9%) of deep wound infection in the 4-level group and 1 case in the 3-level group (1.4%; p = 0.454). Postoperatively, 31% of patients in the 4-level group complained of dysphagia, compared with 12.7% in the 3-level group (p = 0.038). The fusion rate was 84.6% after 4-level ACDF and 94.4% after 3-level ACDF (p = 0.122). At last follow-up, a significantly higher proportion of patients in the 4-level group continued to have axial neck pain (53.8%) than in the 3-level group (31%; p = 0.039); the daily oral morphine equivalent dose was significantly higher in the 4-level group (143 ± 97 mg/day) than in the 3-level group (25 ± 10 mg/day; p = 0.030). Outcomes based on Odom's criteria were also different between cohorts (p = 0.044), with a significantly lower proportion of patients in the 4-level ACDF group experiencing an excellent/good outcome.
In this study, patients who underwent 4-level ACDF had significantly higher rates of dysphagia, postoperative neck pain, and postoperative narcotic usage when compared with patients who underwent 3-level ACDF. Pseudarthrosis and deep wound infection rates were also higher in the 4-level group, although this did not reach statistical significance. Additionally, a smaller proportion of patients achieved a good/excellent outcome in the 4-level group than in the 3-level group. These findings suggest a significant increase of perioperative morbidity and worsened outcomes for patients who undergo 4- versus 3-level ACDF.
Mohamad Bydon, Risheng Xu, David Santiago-Dieppa, Mohamed Macki, Daniel M. Sciubba, Jean-Paul Wolinsky, Ali Bydon, Ziya L. Gokaslan and Timothy F. Witham
The aim of this study was to study the long-term outcomes of patients undergoing instrumented posterior fusion of the lumbar spine.
The authors present 511 patients who underwent instrumented arthrodesis for lumbar degenerative disease over a 23-year period at a single institution. Patients underwent follow-up for an average of 39.73 ± 46.52 months (± SD) after the index lumbar arthrodesis procedure.
The average patient age was 59.45 ± 13.48 years. Of the 511 patients, 502 (98.24%) presented with back pain, 379 (74.17%) with radiculopathy, 76 (14.87%) with motor weakness, and 32 (6.26%) with preoperative bowel/bladder dysfunction. An average of 2.04 ± 1.03 spinal levels were fused. Postoperatively, patients experienced a significant improvement in back pain (p < 0.0001) and radiculopathy (p < 0.0001). Patients with fusions excluding the sacrum (floating fusions) were statistically more likely to develop adjacent-segment disease (ASD) than those with fusion constructs ending at S-1 distally (p = 0.030) but were less likely to develop postoperative radiculopathy (p = 0.030). In the floating fusion cohort, 31 (12.11%) of 256 patients had cephalad ASD, whereas 39 (15.29%) of 255 patients in the lumbosacral cohort had cephalad ASD development; this was not statistically different (p = 0.295). This suggests that caudad ASD development in the floating fusion cohort is due to the added risk of an unfused L5–S1 vertebral level. Because of the elevated risk of symptomatic radiculopathy but lower risk of ASD, patients in the lumbosacral fusion cohort had a reoperation rate similar to those undergoing floating fusions (p = 0.769).
In this paper, the authors present one of the largest cohorts in the Western literature of patients undergoing instrumented fusion for degenerative lumbar spine disease. Patients who had floating lumbar fusions were statistically more likely to develop ASD over time than those who had lumbosacral fusions incorporating the S-1 spinal segment, but were less likely to experience postoperative radicular symptoms. Additional prospective studies may more clearly delineate the long-term risks of instrumented posterolateral fusions of the lumbar spine.
Matthew T. Bender, Geoffrey P. Colby, Li-Mei Lin, Bowen Jiang, Erick M. Westbroek, Risheng Xu, Jessica K. Campos, Judy Huang, Rafael J. Tamargo and Alexander L. Coon
Flow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The existing literature on aneurysm occlusion is limited by heterogeneous follow-up, variable antiplatelet regimens, noninvasive imaging modalities, and nonstandard occlusion assessment. Using a large, single-center cohort with low attrition and standardized antiplatelet tapering, the authors evaluated outcomes after flow diversion of anterior circulation aneurysms to identify predictors of occlusion and aneurysm persistence.
Data from a prospective, IRB-approved database was analyzed for all patients with anterior circulation aneurysms treated by flow diversion with the Pipeline embolization device (PED) at the authors’ institution. Follow-up consisted of catheter cerebral angiography at 6 and 12 months postembolization. Clopidogrel was discontinued at 6 months and aspirin was reduced to 81 mg daily at 12 months. Occlusion was graded as complete, trace filling, entry remnant, or aneurysm filling. Multivariate logistic regression was performed to identify predictors of aneurysm persistence.
Follow-up catheter angiography studies were available for 445 (91%) of 491 PED procedures performed for anterior circulation aneurysms between August 2011 and August 2016. Three hundred eighty-seven patients accounted for these 445 lesions with follow-up angiography. The population was 84% female; mean age was 56 years and mean aneurysm size was 6.6 mm. Aneurysms arose from the internal carotid artery (83%), anterior cerebral artery (13%), and middle cerebral artery (4%). Morphology was saccular in 90% of the lesions, and 18% of the aneurysms has been previously treated. Overall, complete occlusion was achieved in 82% of cases at a mean follow-up of 14 months. Complete occlusion was achieved in 72%, 78%, and 87% at 6, 12, and 24 months, respectively. At 12 months, adjunctive coiling predicted occlusion (OR 0.260, p = 0.036), while male sex (OR 2.923, p = 0.032), aneurysm size (OR 3.584, p = 0.011), and incorporation of a branch vessel (OR 2.206, p = 0.035) predicted persistence. Notable variables that did not predict aneurysm occlusion were prior treatments, vessel of origin, fusiform morphology, and number of devices used.
This is the largest single-institution study showing high rates of anterior circulation aneurysm occlusion after Pipeline embolization. Predictors of persistence after flow diversion included increasing aneurysm size and incorporated branch vessel, whereas adjunctive coiling predicted occlusion.