The Predictors of Incidental Durotomy in Patients Undergoing Pedicle Subtraction Osteotomy for the Correction of Adult Spinal Deformity.

Background: Pedicle subtraction osteotomy (PSO) is a powerful tool for sagittal plane correction in patients with rigid adult spinal deformity (ASD); however, it is associated with high intraoperative blood loss and the increased risk of durotomy. The objective of the present study was to identify intraoperative techniques and baseline patient factors capable of predicting intraoperative durotomy. Methods: A tri-institutional database was retrospectively queried for all patients who underwent PSO for ASD. Data on baseline comorbidities, surgical history, surgeon characteristics and intraoperative maneuvers were gathered. PSO aggressiveness was defined as conventional (Schwab 3 PSO) or an extended PSO (Schwab type 4). The primary outcome of the study was the occurrence of durotomy intraoperatively. Univariable analyses were performed with Mann-Whitney U tests, Chi-squared analyses, and Fisher's exact tests. Statistical significance was defined by p < 0.05. Results: One hundred and sixteen patients were identified (mean age 61.9 ± 12.6 yr; 44.8% male), of whom 51 (44.0%) experienced intraoperative durotomy. There were no significant differences in baseline comorbidities between those who did and did not experience durotomy, with the exception that baseline weight and body mass index were higher in patients who did not suffer durotomy. Prior surgery (OR 2.73; 95% CI [1.13, 6.58]; p = 0.03) and, more specifically, prior decompression at the PSO level (OR 4.23; 95% CI [1.92, 9.34]; p < 0.001) was predictive of durotomy. A comparison of surgeon training showed no statistically significant difference in durotomy rate between fellowship and non-fellowship trained surgeons, or between orthopedic surgeons and neurosurgeons. The PSO level, PSO aggressiveness, the presence of stenosis at the PSO level, nor the surgical instrument used predicted the odds of durotomy occurrence. Those experiencing durotomy had similar hospitalization durations, rates of reoperation and rates of nonroutine discharge. Conclusions: In this large multisite series, a history of prior decompression at the PSO level was associated with a four-fold increase in intraoperative durotomy risk. Notably the use of extended (versus) standard PSO, surgical technique, nor baseline patient characteristics predicted durotomy. Durotomies occurred in 44% of patients and may prolong operative times. Additional prospective investigations are merited.

Spine Surgery Under Spinal vs General Anesthesia: Prospective Analysis of Quality of Life, Fatigue, and Cognition.

BACKGROUND: There has recently been increasing interest in the use of spinal anesthesia (SA) for spine surgery. The literature that compared spine surgery under SA vs general anesthesia (GA) focused on safety, perioperative outcomes, and costs. OBJECTIVE: To test if SA is associated with less postoperative fatigue, cognitive dysfunction, and better quality of life in patients undergoing lumbar spine surgery compared with GA. METHODS: We conducted a prospective nonrandomized study in patients undergoing elective lumbar spine surgery under SA or GA by a single surgeon. Fatigue was assessed with the fatigue visual analog scale scale (0-10) and Chalder Fatigue Scale, quality of life with Medical Outcomes Study 12-item Short Form (SF-12), and differences in cognition with Mini-Mental State Examination. Patients were baselined before surgery and assessed again 1 mo after surgery. RESULTS: Fifty patients completed the study, 25 underwent surgery under SA and 25 under GA. The groups were homogeneous for baseline clinical characteristics, with no differences in preoperative fatigue, quality of life, and cognition. At 1 mo after surgery, SA compared with GA had better fatigue scores: fatigue visual analog scale (2.9 ± 1.5 vs 5.9 ± 2.3 [P < .0001]) and Chalder Fatigue Scale (11.2 ± 3.1 vs 16.9 ± 3.9 [P < .0001]). One month postoperatively, we observed a significant difference in the SF-12 physical component, with SA having 38.8 ± 8.9 vs 29.4 ± 10.3 (P = .002). We did not observe significant postoperative differences in the SF-12 mental component or Mini-Mental State Examination. CONCLUSION: Our study demonstrates that SA offers unique patient-centered advantages to GA for elective spine surgery. One month after surgery, patients who received SA had less postoperative fatigue and better quality of life.

Long-term clinical outcome of minimally invasive versus open single-level transforaminal lumbar interbody fusion for degenerative lumbar diseases: a meta-analysis.

BACKGROUND CONTEXT: Minimally invasive surgical transforaminal lumbar interbody fusion (MIS-TLIF) was developed in addition to open-TLIF to minimize iatrogenic soft-tissue damage. A potential disadvantage of MIS-TLIF is inadequate visualization, which may lead to incomplete neural decompression and a less robust arthrodesis. This may cause long-term problems and result in decreased patient satisfaction. PURPOSE: To evaluate the long-term clinical outcome, measured by patient-reported outcomes (PROMs), of patients with degenerative lumbar diseases treated with single-level TLIF (open vs. minimally invasive) with a minimum follow-up of 2-years. STUDY DESIGN: Meta-analysis. METHODS: The systematic review was conducted according to the PRISMA guidelines. Relevant studies were identified from Pubmed, MEDLINE, EMBASE, Scopus, Web of Science, and CENTRAL from the date of inception to August 2019. The inclusion criteria were (1) longitudinal comparative studies of MIS-TLIF versus open-TLIF approach for degenerative spine disease (2) outcomes reported as PROMs, (3) minimum follow-up of 2-years. RESULTS: Sixteen studies were included in the analysis. In total, 1,321 patients were included (660 MIS-TLIF& 661 open-TLIF). The following PROMS were analyzed: EQ-5D, SF, ODI, and VAS. Both techniques resulted in significant improvement in PROM, which remained significant at 2-years follow-up. However, no significant differences were found in all PROMs at 2-years follow-up. Both treatments resulted in a high rate of spinal fusion (80.5% vs. 91.1%; p=.29) and low rate of reoperation (3.0% vs. 2.4%; p=.50) or adjacent segment disease (12.6% vs. 12.40%; p=.50). CONCLUSIONS: MIS-TLIF and open-TLIF have comparable long-term clinical outscomes. Both operations can significantly reduce pain and positively improve PROMs. No significant differences were found between both treatments in clinical outcomes at a follow-up of minimal 2-years. Therefore, MIS-TLIF seems to be an effective and safe alternative to traditional open-TLIF in the long-term.

Volume of Brain Herniation After Decompressive Craniectomy in Patients with Traumatic Brain Injury.

BACKGROUND: The decompressive hemicraniectomy operation is highly effective in relieving refractory intracranial hypertension. However, one limitation of this treatment strategy is the requirement to perform a subsequent cranioplasty operation to reconstruct the skull defect-an expensive procedure with high complication rates. An implant that is capable of accommodated post-hemicraniectomy brain swelling, but also provides acceptable skull defect coverage after brain swelling abates, would theoretically eliminate the need for the cranioplasty operation. In an earlier report, the concept of using a thin, moveable plate implant for this purpose was introduced. METHODS: Measurements were obtained in a series of stroke patients to determine whether a plate offset from the skull by 5 mm would accommodate the observed post-hemicraniectomy brain swelling. The volume of brain swelling measured in all patients in the stroke series would be accommodated by a 5-mm offset plate. In the current report, we expanded our analysis to study brain swelling patterns in a different population of patients requiring a hemicraniectomy operation: those with traumatic brain injuries (TBI). RESULTS: We identified 56 patients with TBI and measured their postoperative brain herniation volumes. A moveable plate offset by 5 mm would create sufficient additional volume to accommodate the brain swelling measured in all but one patient. That patient had malignant intraoperative brain swelling and died the following day. CONCLUSIONS: These data suggest that a 5 mm offset plate will provide sufficient volume for brain expansion for almost all hemicraniectomy operations.

Deep brain stimulation hardware-related infections: 10-year experience at a single institution.

OBJECTIVEDeep brain stimulation is an effective surgical treatment for managing some neurological and psychiatric disorders. Infection related to the deep brain stimulator (DBS) hardware causes significant morbidity: hardware explantation may be required; initial disease symptoms such as tremor, rigidity, and bradykinesia may recur; and the medication requirements for adequate disease management may increase. These morbidities are of particular concern given that published DBS-related infection rates have been as high as 23%. To date, however, the key risk factors for and the potential preventive measures against these infections remain largely uncharacterized. In this study, the authors endeavored to identify possible risk factors for DBS-related infection and analyze the efficacy of prophylactic intrawound vancomycin powder (VP).METHODSThe authors performed a retrospective cohort study of patients who had undergone primary DBS implantation at a single institution in the period from December 2005 through September 2015 to identify possible risk factors for surgical site infection (SSI) and to assess the impact of perioperative (before, during, and after surgery) prophylactic antibiotics on the SSI rate. They also evaluated the effect of a change in the National Healthcare Safety Network's definition of SSI on the number of infections detected. Statistical analyses were performed using the 2-sample t-test, the Wilcoxon rank-sum test, the chi-square test, Fisher's exact test, or logistic regression, as appropriate for the variables examined.RESULTSFour hundred sixty-four electrodes were placed in 242 adults during 245 primary procedures over approximately 10.5 years; most patients underwent bilateral electrode implantation. Among the 245 procedures, 9 SSIs (3.7%) occurred within 90 days and 16 (6.5%) occurred within 1 year of DBS placement. Gram-positive bacteria were the most common etiological agents. Most patient- and procedure-related characteristics did not differ between those who had acquired an SSI and those who had not. The rate of SSIs among patients who had received intrawound VP was only 3.3% compared with 9.7% among those who had not received topical VP (OR 0.32, 95% CI 0.10-1.02, p = 0.04). After controlling for patient sex, the association between VP and decreased SSI risk did not reach the predetermined level of significance (adjusted OR 0.32, 95% CI 0.10-1.03, p = 0.06). The SSI rates were similar after staged and unstaged implantations.CONCLUSIONSWhile most patient-related and procedure-related factors assessed in this study were not associated with the risk for an SSI, the data did suggest that intrawound VP may help to reduce the SSI risk after DBS implantation. Furthermore, given the implications of SSI after DBS surgery and the frequency of infections occurring more than 90 days after implantation, continued follow-up for at least 1 year after such a procedure is prudent to establish the true burden of these infections and to properly treat them when they do occur.

Risk factors for surgical site infections and assessment of vancomycin powder as a preventive measure in patients undergoing first-time cranioplasty.

OBJECTIVE Craniectomy is often performed to decrease intracranial pressure following trauma and vascular injuries. The subsequent cranioplasty procedures may be complicated by surgical site infections (SSIs) due to prior trauma, foreign implants, and multiple surgeries through a common incision. Several studies have found that intrawound vancomycin powder (VP) is associated with decreased risk of SSIs after spine operations. However, no previously published study has evaluated the effectiveness of VP in cranioplasty procedures. The purpose of this study was to determine whether intrawound VP is associated with decreased risk of SSIs, to evaluate VP's safety, and to identify risk factors for SSIs after cranioplasty among patients undergoing first-time cranioplasty. METHODS The authors conducted a retrospective cohort study of adult patients undergoing first-time cranioplasty for indications other than infections from January 1, 2008, to July 31, 2014, at an academic health center. Data on demographics, possible risk factors for SSIs, and treatment with VP were collected from the patients' electronic health records. RESULTS During the study period, 258 patients underwent first-time cranioplasties, and 15 (5.8%) of these patients acquired SSIs. Ninety-two patients (35.7%) received intrawound VP (VP group) and 166 (64.3%) did not (no-VP group). Patients in the VP group and the no-VP group were similar with respect to age, sex, smoking history, body mass index, and SSI rates (VP group 6.5%, no-VP group 5.4%, p = 0.72). Patients in the VP group were less likely than those in the no-VP group to have undergone craniectomy for tumors and were more likely to have an American Society of Anesthesiologists physical status score > 2. Intrawound VP was not associated with other postoperative complications. Risk factors for SSI from the bivariable analyses were diabetes (odds ratio [OR] 3.65, 95% CI 1.07-12.44), multiple craniotomy procedures before the cranioplasty (OR 4.39, 95% CI 1.47-13.18), prior same-side craniotomy (OR 4.73, 95% CI 1.57-14.24), and prosthetic implants (OR 4.51, 95% CI 1.40-14.59). The multivariable analysis identified prior same-side craniotomy (OR 3.37, 95% CI 1.06-10.79) and prosthetic implants (OR 3.93, 95% CI 1.15-13.40) as significant risk factors for SSIs. After adjusting for potential confounders, patients with SSIs were more likely than those without SSIs to be readmitted (OR 7.28, 95% CI 2.07-25.60). CONCLUSIONS In this study, intrawound VP was not associated with a decreased risk of SSIs or with an increased risk of complications. Prior same-side craniotomy and prosthetic implants were risk factors for SSI after first-time cranioplasty.

Effect of Surgery on Gait and Sensory Motor Performance in Patients With Cervical Spondylotic Myelopathy.

BACKGROUND: Cervical spondylotic myelopathy (CSM) is a common disease of aging that leads to gait instability resulting from loss of leg sensory and motor functions. The results of surgical intervention have been studied using a variety of methods, but no test has been reported that objectively measures integrative leg motor sensory functions in CSM patients. OBJECTIVE: To determine the feasibility of using a novel single leg squat (SLS) test to measure integrative motor sensory functions in patients with CSM before and after surgery. METHODS: Fifteen patients with CSM were enrolled in this prospective study. Clinical data and scores from standard outcomes questionnaires were obtained before and after surgery. Patients also participated in experimental test protocols consisting of standard kinematic gait testing, the Purdue pegboard test, and the novel SLS test. RESULTS: The SLS test protocol was well tolerated by CSM patients and generated objective performance data over short test periods. In patients who participated in postoperative testing, the group measures of mean SLS errors decreased following surgery. Gait velocity measures followed a similar pattern of group improvement postoperatively. Practical barriers to implementing this extensive battery of tests resulted in subject attrition over time. Compared with kinematic gait testing, the SLS protocol required less space and could be effectively implemented more efficiently. CONCLUSIONS: The SLS test provides a practical means of obtaining objective measures of leg motor sensory functions in patients with CSM. Additional testing with a larger cohort of patients is required to use SLS data to rigorously examine group treatment effects. ABBREVIATIONS: BW, body weightCSM, cervical spondylotic myelopathymJOA, modified Japanese Orthopedic AssociationSLS, single leg squat.

Volume of Brain Herniation in Patients with Ischemic Stroke After Decompressive Craniectomy.

BACKGROUND: Decompressive craniectomy procedures are performed in patients with malignant intracranial hypertension. A bone flap is removed to relieve pressure. Later, a second operation is performed to reconstruct the skull after brain swelling has resolved. This surgical treatment would be improved if it were possible to perform a single operation that decompressed the brain acutely and eliminated the need for a second operation. To design a device and procedure that achieve this objective, it is essential to understand how the brain swells after a craniectomy procedure. METHODS: We identified 20 patients with ischemic stroke who underwent a decompressive hemicraniectomy operation. Skull defect morphology and postoperative brain swelling were measured using computed tomography scan data. Additional intracranial volume created by placing a hypothetical cranial plate implant offset from the skull surface by 5 mm was measured for each patient. RESULTS: The average craniectomy area and brain herniation volume was 9999 ± 1283 mm2 and 30.48 ± 23.56 mL, respectively. In all patients, the additional volume created by this hypothetical implant exceeded the volume of brain herniation observed. CONCLUSIONS: These findings show that a cranial plate with a 5-mm offset accommodates the brain swelling that occurs in this patient population.

Rathke's cleft cyst: A case report of recurrence and spontaneous involution.

Rathke's cleft cysts (RCC) are sellar lesions that typically remain asymptomatic throughout life. Symptomatic patients present with headache, visual disturbance and/or pituitary dysfunction and are treated with resection. We present a 61-year-old woman diagnosed with RCC which was resected twice then recurred before undergoing spontaneous resolution. RCC are often managed without surgical intervention. Some of these lesions may spontaneously resolve without surgical intervention while others may become symptomatic. In patients with asymptomatic recurrent RCC conservative management is recommended. Spontaneous involution may occur following initial resection and recurrence of RCC.

Risk factors associated with distal catheter migration following ventriculoperitoneal shunt placement.

Ventriculoperitoneal (VP) shunt placement is used to treat hydrocephalus. Shunt migration following VP shunt placement has been reported. The risk factors related to this complication have not been previously evaluated to our knowledge. In this retrospective cohort study, we aimed to determine risk factors leading to distal catheter migration and review the literature on the current methods of management and prevention. Adult patients undergoing VP shunt placement from June 2011 to December 2013 at a single institution were identified using electronic health records. The records were reviewed for demographic and procedural information, and subsequent treatment characteristics. The parameters of patients with distal shunt migration were compared to those undergoing new VP shunt placement for the same time period. We identified 137 patients undergoing 157 new VP shunt procedures with an average age of 57.7 ± standard deviation of 18.4 years old. There were 16 distal shunt migrations. Body mass index >30 kg/m(2) and number of previous shunt procedures were found to be independent risk factors for distal catheter migration. Obesity and number of previous shunt procedures were factors for distal catheter migration. Providers and patients should be aware of these possible risk factors prior to VP shunt placement.

Management of spinal fractures in patients with ankylosing spondylitis.

Ankylosing spondlylitis is a seronegative spondyloarthropathy that primarily affects the spinal column and sacroiliac joints. With disease progression autofusion of the spinal column takes place. This combined with the brittle bone quality make patients prone to fractures and spinal cord injury. The typical fracture pattern is extension type and involves all three columns. These fractures and injuries may involve the craniovertebral junction, the subaxial cervical spine, and the thoracolumbar spine. While at times these fractures are challenging to manage especially when they affect the elderly, there is evidence that supports long segment fixation and fusion. This article presents a narrative review on managing spinal fractures in patients with ankylosing spondylitis.

Isolated Supratentorial Intraventricular Recurrence of Medulloblastoma.

Medulloblastoma is a common pediatric tumor typically diagnosed before the age of fifteen. Initial therapy includes surgical resection and radiation of the entire neuro-axis. Recurrence is common and typically occurs within 2 years of initial diagnosis. Those fitting Collin's Law is considered tumor-free. We report a case of single supratentorial recurrence 13 years after initial diagnosis. Here we present a 22 year old male presenting 13 years after initial diagnosis with isolated septum pellucidum recurrence. He underwent complete resection of the tumor. Medulloblastoma is a common in the pediatric population. Late recurrence to the ventricular system is uncommon. Long term follow-up is recommended in these patients.

Cervical decompression and reconstruction without intraoperative neurophysiological monitoring.

OBJECT: The primary goal of this study was to review the immediate postoperative neurological function in patients surgically treated for symptomatic cervical spine disease without intraoperative neurophysiological monitoring. The secondary goal was to assess the economic impact of intraoperative monitoring (IOM) in this patient population. METHODS: This study is a retrospective review of 720 consecutively treated patients who underwent cervical spine procedures. The patients were identified and the data were collected by individuals who were not involved in their care. RESULTS: A total of 1534 cervical spine levels were treated in 720 patients using anterior, posterior, and combined (360°) approaches. Myelopathy was present preoperatively in 308 patients. There were 185 patients with increased signal intensity within the spinal cord on preoperative T2-weighted MR images, of whom 43 patients had no clinical evidence of myelopathy. Three patients (0.4%) exhibited a new neurological deficit postoperatively. Of these patients, 1 had a preoperative diagnosis of radiculopathy, while the other 2 were treated for myelopathy. The new postoperative deficits completely resolved in all 3 patients and did not require additional treatment. The Current Procedural Terminology (CPT) codes for IOM during cervical decompression include 95925 and 95926 for somatosensory evoked potential monitoring of the upper and lower extremities, respectively, as well as 95928 and 95929 for motor evoked potential monitoring of the upper and lower extremities. In addition to the charge for the baseline [monitoring] study, patients are charged hourly for ongoing electrophysiology testing and monitoring using the CPT code 95920. Based on these codes and assuming an average of 4 hours of monitoring time per surgical case, the savings realized in this group of patients was estimated to be $1,024,754. CONCLUSIONS: With the continuing increase in health care costs, it is our responsibility as providers to minimize expenses when possible. This should be accomplished without compromising the quality of care to patients. This study demonstrates that decompression and reconstruction for symptomatic cervical spine disease without IOM may reduce the cost of treatment without adversely impacting patient safety.

Complications associated with recombinant human bone morphogenetic protein use in pediatric craniocervical arthrodesis.

OBJECT: Management of pediatric occipitocervical instability remains especially challenging. The off-label use of recombinant human bone morphogenetic protein (rhBMP)-2 for spinal fusion has increased with a well-documented increase in fusion rate in many case series. Unfortunately, recent reports have documented complications associated with rhBMP use in adult spinal fusions. Complications associated with the use of rhBMP in pediatric spinal surgery is less well understood. In this study the authors report on the fusion rate and complications associated with rhBMP in pediatric occipitocervical arthrodesis. METHODS: The authors reviewed the medical records of those patients 18 years old and younger who underwent dorsal occipitocervical fusion from January 2004 to December 2007 at the University of Iowa Hospitals and Clinics. Forty-eight patients were identified who received rhBMP-augmented fusion. The clinical outcome and complications of these fusions were analyzed. RESULTS: All 48 patients had fusion confirmed on lateral radiographs within 4-14 months with an average fusion time of 6.7 months. There were 6 complications, 5 of which included seroma formation. Two of 5 patients who developed postoperative seroma presented with symptoms suggesting brainstem compression and obstructive hydrocephalus requiring emergency reoperation. One patient developed heterotopic bone formation causing cervicomedullary compression requiring reoperation. CONCLUSIONS: The use of rhBMP to augment autograft in occipitocervical fusion allows for a high rate of successful arthrodesis, but is associated with potentially life-threatening complications in pediatric patients.