Malignant primary tumors of scalp with cranial extension: multidisciplinary surgical strategies and outcomes.

OBJECTIVE: Malignant cancers arising in the scalp may exhibit calvarial invasion, dural extension, and rarely cerebral involvement. Typically, such lesions require a multidisciplinary approach involving both neurosurgery and plastic surgery for optimal resection and reconstruction. The authors present a retrospective analysis of patients with scalp malignancies who underwent resection and reconstruction. METHODS: Patients presenting with scalp malignancies (1993-2021, n = 84) who required neurosurgical assistance for tumor resection were prospectively entered into a database. These data were retrospectively reviewed for this case series. The extent of neurosurgical resection was classified into four levels of involvement: scalp (level I), calvarial (level II), dural (level III), or intraparenchymal (level IV). Complications and evidence of local, locoregional, or regional recurrence were documented. RESULTS: Patients underwent level I (n = 2), level II (n = 61), level III (n = 13), and level IV (n = 8) resections. Pathologies consisted of primarily squamous cell carcinoma (n = 50, 59.5%), basal cell carcinoma (n = 11, 13.1%), and melanoma (n = 9, 10.7%), with infrequent lesions including sarcoma, atypical fibroxanthoma, and malignant fibrous histiocytoma. For cases requiring a cranioplasty, 92.2% were done using titanium mesh and 7.8% with methylmethacrylate. At a mean follow-up of 35.5 ± 45.9 months, the overall survival was 48.8% (n = 41) and recurrence-free survival was 31.0% (n = 43). Scalp-based reconstruction involving plastic surgery was performed in 75 (89.3%) patients. The most commonly used free flap was a latissimus dorsi muscle flap (n = 46, 61.3%). One or more postoperative complications occurred in 21.4% of all patients, the most common being wound dehiscence or delayed wound healing in 13% (n = 11). CONCLUSIONS: A multidisciplinary approach with aggressive neurosurgical resection is associated with good outcomes in patients with primary malignant scalp tumors, despite invasive disease on presentation. This analysis suggests that aggressive resection (level II and higher) is effective at reducing locoregional recurrence and is not associated with a higher risk of complications relative to resection without craniectomy. As most patients require scalp reconstruction to close the postresection defect, usually with vascularized free tissue transfer, involving a plastic surgeon in the surgical planning and execution is essential.

Long-Term Reoperation Rates After Open versus Minimally Invasive Spine Surgery for Degenerative Lumbar Disease: Five Year Follow-Up of 2130 Patients.

BACKGROUND: Minimally Invasive Spine Surgery (MISS) is a growing alternative to Open Spine Surgery (OSS). The preservation of musculature and minimization of iatrogenic injury is hypothesized to decrease the need for reoperation by preserving normal anatomy. Our objective is to compare the relative long-term reoperation rates after MISS and OSS for the treatment of degenerative disease of the lumbar spine. METHODS: This retrospective analysis compares the long-term reoperation rates after MISS and OSS. Eligible patients were adults with a primary lumbar intervention carried out between 5/1/2004 and 1/31/2014 to allow for at least 5 years of follow up. Patients without sufficient descriptive metrics or follow-up data were excluded. The primary outcome was the rate of lumbar spine reoperation. RESULTS: A total of 2130 patients met the inclusion criteria-1895 underwent OSS and 235 underwent MISS. On average and across all surgery types (decompression and decompression with fusion), 28% of OSS patients required reoperation during the minimum 5-year follow up period while only 14% of MISS patients required reoperation (P = 0.001). The MISS group was statistically identical to the OSS group in all categories except that the MISS group was on average 1.8 years older (62.25 vs. 60.45, P = 0.039) and had a higher incidence of diabetes (26% vs. 17%, P = 0.000), but had a lower average body mass index than the OSS group (28.35 vs. 29.60, P = 0.002). CONCLUSIONS: In the setting of degenerative lumbar spine disease, MISS has the potential to reduce the long-term need for reoperation when compared with OSS.

The Addition of Radiofrequency Tumor Ablation to Kyphoplasty May Reduce the Rate of Local Recurrence in Spinal Metastases Secondary to Breast Cancer.

BACKGROUND: Approximately 10% of all cancer patients develop spinal metastases. When a symptomatic compression fracture occurs without associated deformity or neurologic deficit, it can be treated with kyphoplasty with or without radiofrequency ablation (RFA). Treatment with kyphoplasty is well established but does not address the underlying oncologic disease. METHODS: Retrospective medical chart analysis of breast cancer patients (n = 23) with metastatic spinal fractures (n = 50 vertebral levels) who underwent RFA and kyphoplasty was undertaken. Key variables of interest included: fracture location, pain levels, and local recurrence. Local recurrence data were compared to published rates of recurrence in breast cancer-related metastatic spinal fractures treated with vertebroplasty or kyphoplasty alone. Data were analyzed using χ2 and t test statistical analyses. RESULTS: The mean preoperative pain level for this cohort was 6.9 on a 10-point visual analogue scale. Significant reductions in pain levels were observed postoperatively, at discharge (3.5; P < 0.05), at 1-month follow-up (2.8; P < 0.05), at 3-month follow-up (1.1; P < 0.05), and at 6-month follow-up (0.7 P < 0.05). Compared with published data of breast cancer patients with metastatic spinal fractures treated with vertebroplasty or kyphoplasty alone, the addition of RFA resulted in reduced local tumor recurrence (2% vs. 14%; P < 0.05). Average length of follow-up was 39 months. CONCLUSIONS: The results suggest that the addition of RFA to kyphoplasty may reduce local tumor recurrence while providing similar pain relief benefits. The extrapolation of this added benefit to metastases from other primary cancers should be examined in future studies.

Anatomical Variations of the Recurrent Laryngeal Nerve and Implications for Injury Prevention during Surgical Procedures of the Neck.

Accurate knowledge of anatomical variations of the recurrent laryngeal nerve (RLN) provides information to prevent inadvertent intraoperative injury and ultimately guide best clinical and surgical practices. The present study aims to assess the potential anatomical variability of RLN pertaining to its course, branching pattern, and relationship to the inferior thyroid artery, which makes it vulnerable during surgical procedures of the neck. Fifty-five formalin-fixed cadavers were carefully dissected and examined, with the course of the RLN carefully evaluated and documented bilaterally. Our findings indicate that extra-laryngeal branches coming off the RLN on both the right and left side innervate the esophagus, trachea, and mainly intrinsic laryngeal muscles. On the right side, 89.1% of the cadavers demonstrated 2-5 extra-laryngeal branches. On the left, 74.6% of the cadavers demonstrated 2-3 extra-laryngeal branches. In relation to the inferior thyroid artery (ITA), 67.9% of right RLNs were located anteriorly, while 32.1% were located posteriorly. On the other hand, 32.1% of left RLNs were anterior to the ITA, while 67.9% were related posteriorly. On both sides, 3-5% of RLN crossed in between the branches of the ITA. Anatomical consideration of the variations in the course, branching pattern, and relationship of the RLNs is essential to minimize complications associated with surgical procedures of the neck, especially thyroidectomy and anterior cervical discectomy and fusion (ACDF) surgery. The information gained in this study emphasizes the need to preferentially utilize left-sided approaches for ACDF surgery whenever possible.

Cervical Spine and Craniocervical Junction Reconstruction with a Vascularized Fibula Free Flap.

BACKGROUND: Long-term stabilization of the cervical spine after extensive multilevel tumor resection is difficult to achieve. The current standard approach of instrumentation combined with allograft or nonvascularized autograft is limited in settings of increased risk of nonunion or delayed union (i.e., prior radiation therapy or poorly vascularized wound beds). CASE DESCRIPTION: We report the first time to our knowledge that a vascularized fibular free flap has been used to reconstruct the cervical column across 5 vertebral levels, from the craniocervical junction to the lower cervical spine. We describe a transoral approach to the area and compare this method with other reconstructive options. CONCLUSIONS: Vascularized bone grafting is a viable alternative to achieve lasting stability because of hastened fusion time, limited reliance on osseous remodeling, and incorporation into the axial skeleton with strut strength.

Histopathological Findings After Reirradiation Compared to First Irradiation of Spinal Bone Metastases With Stereotactic Body Radiotherapy: A Cohort Study.

BACKGROUND: Stereotactic body radiotherapy (SBRT) of the spine provides superior tumor control, but vertebral compression fractures are increased and the pathophysiological process underneath is not well understood. Data on histopathological changes, particularly after salvage SBRT (sSBRT) following conventional irradiation, are scarce. OBJECTIVE: To investigate surgical specimens after sSBRT and primary SBRT (pSBRT) regarding histopathological changes. METHODS: We assessed 704 patients treated with spine SBRT 2006 to 2012. Thirty patients underwent salvage surgery; 23 histopathological reports were available. Clinical and histopathological findings were analyzed for sSBRT (69.6%) and pSBRT (30.4%). RESULTS: Mean time to surgery after sSBRT/pSBRT was 8.3/10.3 mo (P = .64). Reason for surgery included pain (sSBRT/pSBRT: 12.5%/71.4%, P = .25), fractures (sSBRT/pSBRT: 37.5%/28.6%, P = .68), and neurological symptoms (sSBRT/pSBRT: 68.8%/42.9%, P = .24). Radiological tumor progression after sSBRT/pSBRT was seen in 71.4%/42.9% (P = .2). Most specimens displayed viable/proliferative tumor (sSBRT/pSBRT: 62.5%/71.4%, P = .68 and 56.3%/57.1%, P = .97). Few specimens showed soft tissue necrosis (sSBRT/pSBRT: 20%/28.6%, P = .66), osteonecrosis (sSBRT/pSBRT: 14.3%/16.7%, P = .89), or bone marrow fibrosis (sSBRT/pSBRT: 42.9%/33.3%, P = .69). Tumor bed necrosis was more common after sSBRT (81.3%/42.9%, P = .066). Radiological tumor progression correlated with viable/proliferative tumor (P = .03/P = .006) and tumor bed necrosis (P = .03). Fractures were increased with bone marrow fibrosis (P = .07), but not with osteonecrosis (P = .53) or soft tissue necrosis (P = .19). Neurological symptoms were common with radiological tumor progression (P = .07), but not with fractures (P = .18). CONCLUSION: For both, sSBRT and pSBRT, histopathological changes were similar. Neurological symptoms were attributable to tumor progression and pathological fractures were not associated with osteonecrosis or tumor progression.

Safety and efficacy of balloon kyphoplasty at 4 or more levels in a single anesthetic session.

OBJECTIVE In this case series, the authors evaluated the safety of balloon kyphoplasty at 4 or more vertebral levels in a single anesthetic session. The current standard is that no more than 3 levels should be cemented at one time because of a perceived risk of increased complications. METHODS A retrospective chart review was performed for 19 consecutive patients who underwent ≥ 4-level balloon kyphoplasty between July 1, 2011, and December 31, 2015. Outcomes documented included kyphoplasty-associated complications and incidences of subsequent vertebral fracture. RESULTS Nineteen patients aged 22 to 95 years (mean 66.1 years, median 66 years; 53% male, 47% female) had 4 or more vertebrae cemented during the same procedure (mean 4.6 levels [62 thoracic, 29 lumbar]). No postoperative anesthetic complication, infection, extensive blood loss, symptomatic cement leakage, pneumothorax, or new-onset anemia was observed. Five patients experienced new compression fracture within a mean of 278 days postoperatively. One patient with metastatic cancer suffered bilateral pulmonary embolism 19 days after surgery, but no evidence of cement in the pulmonary vasculature was found. CONCLUSIONS In this case series, kyphoplasty performed on 4 or more vertebral levels was not found to increase risk to patient safety, and it might decrease unnecessary risks associated with multiple operations. Also, morbidity associated with leaving some fractures untreated because of an unfounded fear of increased risk of complications might be decreased by treating 4 or more levels in the same anesthetic session.

Risk for surgical complications after previous stereotactic body radiotherapy of the spine.

OBJECT: Stereotactic body radiotherapy (SBRT) for vertebral metastases has emerged as a promising technique, offering high rates of symptom relief and local control combined with low risk of toxicity. Nonetheless, local failure or vertebral instability may occur after spine SBRT, generating the need for subsequent surgery in the irradiated region. This study evaluated whether there is an increased incidence of surgical complications in patients previously treated with SBRT at the index level. METHODS: Based upon a retrospective international database of 704 cases treated with SBRT for vertebral metastases, 30 patients treated at 6 different institutions were identified who underwent surgery in a region previously treated with SBRT. RESULTS: Thirty patients, median age 59 years (range 27-84 years) underwent SBRT for 32 vertebral metastases followed by surgery at the same vertebra. Median follow-up time from SBRT was 17 months. In 17 cases, conventional radiotherapy had been delivered prior to SBRT at a median dose of 30 Gy in median 10 fractions. SBRT was administered with a median prescription dose of 19.3 Gy (range 15-65 Gy) delivered in median 1 fraction (range 1-17) (median EQD2/10 = 44 Gy). The median time interval between SBRT and surgical salvage therapy was 6 months (range 1-39 months). Reasons for subsequent surgery were pain (n = 28), neurological deterioration (n = 15) or fracture of the vertebral body (n = 13). Open surgical decompression (n = 24) and/or stabilization (n = 18) were most frequently performed; Five patients (6 vertebrae) were treated without complications with vertebroplasty only. Increased fibrosis complicating the surgical procedure was explicitly stated in one surgical report. Two durotomies occurred which were closed during the operation, associated with a neurological deficit in one patient. Median blood loss was 500 ml, but five patients had a blood loss of more than 1 l during the procedure. Delayed wound healing was reported in two cases. One patient died within 30 days of the operation. CONCLUSION: In this series of surgical interventions following spine SBRT, the overall complication rate was 19%, which appears comparable to primary surgery without previous SBRT. Prior spine SBRT does not appear to significantly increase the risk of intra- and post-surgical complications.

Prognostic Factors and Survival Outcome in Patients with Chordoma in the United States: A Population-Based Analysis.

OBJECTIVE: To evaluate prognostic factors of patients with chordoma through a population-based analysis. METHODS: Surveillance, Epidemiology, and End Results (SEER) database was queried for patients with chordoma from 1973 to 2013. Kaplan-Meier univariate analysis and Cox regression multivariate analysis were performed to examine prognostic factors in overall survival (OS) and disease-specific survival (DSS). RESULTS: One thousand five hundred ninety-eight patients with chordoma are identified. Kaplan-Meier analysis showed that OS and DSS were 61% and 71% at 5 years and 41% and 57% at 10 years. Multivariate Cox regression analysis demonstrated that independent predictors of OS and DSS are age at diagnosis (hazard ratio [HR]= 2.80 [95% confidence interval {CI}, 2.12-3.70], P < 0.001; HR = 1.60 [95% CI, 1.18-2.16], P = 0.002), surgical treatment (HR = 0.62 [95% CI, 0.52-0.73], P < 0.001; HR = 0.64 [95% CI, 0.52-0.79], P < 0.001), radiation therapy (HR = 1.23 [95% CI, 1.07-1.42], P = 0.004; HR = 1.29 [95% CI, 1.09-1.54], P = 0.004), tumor size (HR = 1.53 [95% CI, 1.32-1.78], P < 0.001; HR = 1.62 [95% CI, 1.35-1.94], P < 0.001) and distant metastasis (HR = 3.40 [95% CI, 2.45-4.71], P < 0.001; HR = 3.77 [95% CI, 2.61-5.45], P < 0.001). CONCLUSION: We report the largest study to date to evaluate prognostic factors of patients with chordoma. Multivariate analysis demonstrated that older age, greater tumor size, and distant metastasis were correlated with decreased survival, whereas surgical resection was correlated with increased survival. Patients receiving radiation therapy also showed decreased survival, likely an indication of the patients' advanced stage of disease, making them poor surgical candidates.

Re-irradiation stereotactic body radiotherapy for spinal metastases: a multi-institutional outcome analysis.

OBJECTIVE This study is a multi-institutional pooled analysis specific to imaging-based local control of spinal metastases in patients previously treated with conventional external beam radiation therapy (cEBRT) and then treated with re-irradiation stereotactic body radiotherapy (SBRT) to the spine as salvage therapy, the largest such study to date. METHODS The authors reviewed cases involving 215 patients with 247 spinal target volumes treated at 7 institutions. Overall survival was calculated on a patient basis, while local control was calculated based on the spinal target volume treated, both using the Kaplan-Meier method. Local control was defined as imaging-based progression within the SBRT target volume. Equivalent dose in 2-Gy fractions (EQD2) was calculated for the cEBRT and SBRT course using an α/ß of 10 for tumor and 2 for both spinal cord and cauda equina. RESULTS The median total dose/number of fractions of the initial cEBRT was 30 Gy/10. The median SBRT total dose and number of fractions were 18 Gy and 1, respectively. Sixty percent of spinal target volumes were treated with single-fraction SBRT (median, 16.6 Gy and EQD2/10 = 36.8 Gy), and 40% with multiple-fraction SBRT (median 24 Gy in 3 fractions, EQD2/10 = 36 Gy). The median time interval from cEBRT to re-irradiation SBRT was 13.5 months, and the median duration of patient follow-up was 8.1 months. Kaplan-Meier estimates of 6- and 12-month overall survival rates were 64% and 48%, respectively; 13% of patients suffered a local failure, and the 6- and 12-month local control rates were 93% and 83%, respectively. Multivariate analysis identified Karnofsky Performance Status (KPS) < 70 as a significant prognostic factor for worse overall survival, and single-fraction SBRT as a significant predictive factor for better local control. There were no cases of radiation myelopathy, and the vertebral compression fracture rate was 4.5%. CONCLUSIONS Re-irradiation spine SBRT is effective in yielding imaging-based local control with a clinically acceptable safety profile. A randomized trial would be required to determine the optimal fractionation.

Using Provocative Discography and Computed Tomography to Select Patients with Refractory Discogenic Low Back Pain for Lumbar Fusion Surgery.

Background Context Controversy remains over the use of provocative discography in conjunction with computed tomography (CT) to locate symptomatic intervertebral discs in patients with chronic, low back pain (LBP). The current study explores the relationship between discogenic pain and disc morphology using discography and CT, respectively, and investigates the efficacy of this combined method in identifying surgical candidates for lumbar fusion by evaluating outcomes. Methods 43 consecutive patients between 2006 and 2013 who presented with refractory low back pain and underwent discography and CT were enrolled in the study. For this study, "refractory LBP" was defined as pain symptoms that persisted or worsened after 6 months of non-operative treatments. Concordant pain was defined as discography-provoked LBP of similar character and location with an intensity of ≥ 8/10. Fusion candidates demonstrated positive-level discography and concordant annular tears on CT at no more than two contiguous levels, and at least one negative control disc with intact annulus. Surgical outcomes were statistically analyzed using Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Short Form-36 (SF-36) for back-related pain and disability preoperatively, and 2 weeks, 3, 6, 12, and 24 months postoperatively. Results Annular tears were found in 87 discs. Concordant pain was reported by 9 (20.9%) patients at L3-L4, 21 (50.0%) at L4-L5, and 34 (82.9%) at L5-S1; pain occurred significantly more often in discs with annular tears than those without (p<0.001). Painless discs were independent of annulus status (p=0.90). 18 (42%) of the original 43 patients underwent lumbar fusion at L3-L4 (n=1(6%)), L4-L5 (n=6 (33%)), L5-S1 (n=5 (28%)), and two-level L4-S1 (n=6 (33%)) via a minimally invasive transforaminal lumbar interbody fusion (MITLIF) approach with the aim to replace the nucleus pulposus with bone graft material. Median follow-up time was 18 months (range: 12-78 months). VAS, ODI, and SF-36 scores demonstrated significant improvements at 10 out of 12 postoperative time points compared with preoperative baseline. Conclusions Lumbar discography with post-discography CT can be an effective method to evaluate patients with discogenic back pain refractory to non-operative treatments. Those patients with one- or two-level high concordant pain scores with associated annular tears and negative control disc represent good surgical candidates for lumbar interbody spinal fusion.

Vertebral compression fractures after stereotactic body radiation therapy: a large, multi-institutional, multinational evaluation.

OBJECTIVE The purpose of this study was to identify factors contributing to an increased risk for vertebral compression fracture (VCF) following stereotactic body radiation therapy (SBRT) for spinal tumors. METHODS A total of 594 tumors were treated with spinal SBRT as primary treatment or re-irradiation at 8 different institutions as part of a multi-institutional research consortium. Patients underwent LINAC-based, image-guided SBRT to a median dose of 20 Gy (range 8-40 Gy) in a median of 1 fraction (range 1-5 fractions). Median patient age was 62 years. Seventy-one percent of tumors were osteolytic, and a preexisting vertebral compression fracture (VCF) was present in 24% of cases. Toxicity was assessed following treatment. Univariate and multivariate analyses were performed using a logistic regression method to determine parameters predictive for post-SBRT VCF. RESULTS At a median follow-up of 10.1 months (range 0.03-57 months), 80% of patients had local tumor control. At the time of last imaging follow-up, at a median of 8.8 months after SBRT, 3% had a new VCF, and 2.7% had a progressive VCF. For development of any (new or progressive) VCF following SBRT, the following factors were predictive for VCF on univariate analysis: short interval from primary diagnosis to SBRT (less than 36.8 days), solitary metastasis, no additional bone metastases, no prior chemotherapy, preexisting VCF, no MRI used for target delineation, tumor volume of 37.3 cm(3) or larger, equivalent 2-Gy-dose (EQD2) tumor of 41.8 Gy or more, and EQD2 spinal cord Dmax of 46.1 Gy or more. Preexisting VCF, solitary metastasis, and prescription dose of 38.4 Gy or more were predictive on multivariate analysis. The following factors were predictive of a new VCF on univariate analysis: solitary metastasis, no additional bone metastases, and no MRI used for target delineation. Presence of a solitary metastasis and lack of MRI for target delineation remained significant on multivariate analysis. CONCLUSIONS A VCF following SBRT is more likely to occur following treatment for a solitary spinal metastasis, reflecting a more aggressive treatment approach in patients with adequately controlled systemic disease. Higher prescription dose and a preexisting VCF also put patients at increased risk for post-SBRT VCF. In these patients, pre-SBRT cement augmentation could be considered to decrease the risk of subsequent VCF.

Utility of Preoperative Magnetic Resonance Imaging Coregistered with Intraoperative Computed Tomographic Scan for the Resection of Complex Tumors of the Spine.

BACKGROUND: Complete surgical resection is known to provide the best prognosis when treating complex tumors of the spine. The anatomy of the cervical spine and the extensive involvement often present by the time these lesions are discovered can make total resection challenging. A novel technique combining preoperative and intraoperative imaging for intraoperative navigation can serve as an additional tool for facilitating tumor resection. METHODS: Preoperative MRI was coregistered with intraoperative CT for accurate, real-time, intraoperative navigation for complete resection of complex tumors of the cervical spine. This new technique is demonstrated. The potential advantages and challenges are discussed. RESULTS: Preoperative MRI coregistered and merged with intraoperative CT allows for accurate visualization of tumor boundaries, osseous anatomy, and surrounding soft tissue structures. Total resection of extensive spinal tumors involving the anterior and posterior elements can be facilitated with this technique. CONCLUSIONS: Preoperative MRI coregistered and merged with intraoperative CT may serve as a useful intraoperative imaging modality for facilitating safe and complete resection of complex spine tumors.

Factors affecting survival in 43 consecutive patients after surgery for spinal metastases from thyroid carcinoma.

OBJECT: Spinal metastases account for the majority of bone metastases from thyroid cancer. The objective of the current study was to analyze a series of consecutive patients undergoing spinal surgery for thyroid cancer metastases in order to identify factors that influence overall survival. METHODS: The authors retrospectively reviewed the records of all patients who underwent surgery for spinal metastases from thyroid cancer between 1993 and 2010 at the University of Texas MD Anderson Cancer Center. RESULTS: Forty-three patients met the study criteria. Median overall survival was 15.4 months (95% CI 2.8-27.9 months) based on the Kaplan-Meier method. The median follow-up duration for the 4 patients who were alive at the end of the study was 39.4 months (range 1.7-62.6 months). On the multivariate Cox analysis, progressive systemic disease at spine surgery and postoperative complications were associated with worse overall survival (HR 8.98 [95% CI 3.46-23.30], p < 0.001; and HR 2.86 [95% CI 1.30-6.31], p = 0.009, respectively). Additionally, preoperative neurological deficit was significantly associated with worse overall survival on the multivariate analysis (HR 3.01 [95% CI 1.34-6.79], p = 0.008). Conversely, preoperative embolization was significantly associated with improved overall survival on the multivariate analysis (HR 0.43 [95% CI 0.20-0.94], p = 0.04). Preoperative embolization and longer posterior construct length were significantly associated with fewer and greater complications, respectively, on the univariate analysis (OR 0.24 [95% CI 0.06-0.93] p = 0.04; and OR 1.24 [95% CI 1.02-1.52], p = 0.03), but not the multivariate analysis. CONCLUSIONS: Progressive systemic disease, postoperative complications, and preoperative neurological deficits were significantly associated with worse overall survival, while preoperative spinal embolization was associated with improved overall survival. These factors should be taken into consideration when considering such patients for surgery. Preoperative embolization and posterior construct length significantly influenced the incidence of postoperative complications only on the univariate analysis.

Definitive single-stage posterior surgical correction of complete traumatic spondyloptosis at the thoracolumbar junction.

Complete dislocation at the thoracolumbar junction is a rare occurrence, with only 4 previously reported cases in 3 separate series. Surgical procedures in the reported cases of spondyloptosis at the thoracolumbar junction have been described using instrumentation, reduction, decompression, and stabilization techniques. In this report the authors' patient presented with spondyloptosis at the thoracolumbar junction, resulting in a T-11 American Spinal Injury Association Grade A injury. The authors corrected the patient's thoracolumbar spondyloptosis with surgical reconstruction without the use of leveraged instrumented reduction. They describe a single-stage, posterior-only spinal realignment, reconstruction, and stabilization. Within months of beginning postoperative therapy, the patient enrolled and attended courses at a local college and regained personal independence by learning to drive a motor vehicle with a hand control. Two-year radiographic and clinical follow-up confirms solid fusion across the reconstruction.

A rare case of giant cell tumor involving the clivus resected through Le Fort I Osteotomy and median maxillotomy.

BACKGROUND: Giant cell tumors (GCTs) are bone tumors that seldom involve the skull. Skull GCTs preferentially occur in the sphenoid and temporal bones with few reported cases involving the clivus. Due to the rarity and complex location, surgical management is not well established for clival GCTs. CASE DESCRIPTION: A 49-year-old male presented with headaches and blurred vision in the right eye for 2 weeks. Computed tomography (CT) with contrast revealed a sellar mass eroding through the sphenoid sinuses with compression of optic chiasm. Biopsy was consistent with GCT. Patient underwent tumor resection by Le Fort I Osteotomy and median maxillotomy for an extended transsphenoidal approach. Upon discharge, patient showed no neurological deficits and intact cranial nerves. CONCLUSION: This case contributes to the limited amount of skull-based GCT cases worldwide. Additionally, the extended transoral approach can be performed safely in the context of a GCT within the clivus with acceptable morbidity and cosmesis.

Safety and efficacy of stereotactic body radiotherapy as primary treatment for vertebral metastases: a multi-institutional analysis.

PURPOSE: To evaluate patient selection criteria, methodology, safety and clinical outcomes of stereotactic body radiotherapy (SBRT) for treatment of vertebral metastases. MATERIALS AND METHODS: Eight centers from the United States (n=5), Canada (n=2) and Germany (n=1) participated in the retrospective study and analyzed 301 patients with 387 vertebral metastases. No patient had been exposed to prior radiation at the treatment site. All patients were treated with linac-based SBRT using cone-beam CT image-guidance and online correction of set-up errors in six degrees of freedom. RESULTS: 387 spinal metastases were treated and the median follow-up was 11.8 months. The median number of consecutive vertebrae treated in a single volume was one (range, 1-6), and the median total dose was 24 Gy (range 8-60 Gy) in 3 fractions (range 1-20). The median EQD210 was 38 Gy (range 12-81 Gy). Median overall survival (OS) was 19.5 months and local tumor control (LC) at two years was 83.9%. On multivariate analysis for OS, male sex (p<0.001; HR=0.44), performance status <90 (p<0.001; HR=0.46), presence of visceral metastases (p=0.007; HR=0.50), uncontrolled systemic disease (p=0.007; HR=0.45), >1 vertebra treated with SBRT (p=0.04; HR=0.62) were correlated with worse outcomes. For LC, an interval between primary diagnosis of cancer and SBRT of ≤ 30 months (p=0.01; HR=0.27) and histology of primary disease (NSCLC, renal cell cancer, melanoma, other) (p=0.01; HR=0.21) were correlated with worse LC. Vertebral compression fractures progressed and developed de novo in 4.1% and 3.6%, respectively. Other adverse events were rare and no radiation induced myelopathy reported. CONCLUSIONS: This multi-institutional cohort study reports high rates of efficacy with spine SBRT. At this time the optimal fractionation within high dose practice is unknown.

Impact of preoperative functional magnetic resonance imaging during awake craniotomy procedures for intraoperative guidance and complication avoidance.

BACKGROUND: We wanted to study the role of functional MRI (fMRI) in preventing neurological injury in awake craniotomy patients as this has not been previously studied. OBJECTIVES: To examine the role of fMRI as an intraoperative adjunct during awake craniotomy procedures. METHODS: Preoperative fMRI was carried out routinely in 214 patients undergoing awake craniotomy with direct cortical stimulation (DCS). RESULTS: In 40% of our cases (n = 85) fMRI was utilized for the intraoperative localization of the eloquent cortex. In the other 129 cases significant noise distortion, poor task performance and nonspecific BOLD activation precluded the surgeon from using the fMRI data. Compared with DCS, fMRI had a sensitivity and specificity, respectively, of 91 and 64% in Broca's area, 93 and 18% in Wernicke's area and 100 and 100% in motor areas. A new intraoperative neurological deficit during subcortical dissection was predictive of a worsened deficit following surgery (p < 0.001). The use of fMRI for intraoperative localization was, however, not significant in preventing worsened neurological deficits, both in the immediate postoperative period (p = 1.00) and at the 3-month follow-up (p = 0.42). CONCLUSIONS: The routine use of fMRI was not useful in identifying language sites as performed and, more importantly, practiced tasks failed to prevent neurological deficits following awake craniotomy procedures.

Orthotopic murine model of a primary malignant bone tumor in the spine: functional, bioluminescence, and histological correlations.

OBJECT: There is currently no reproducible animal model of human primary malignant bone tumors in the spine to permit laboratory investigation of the human disease. Therefore, the authors sought to adapt their previously developed orthotopic model of spinal metastasis to a model for primary malignant bone tumors of the spine. METHODS: A transperitoneal surgical approach was used to implant osteosarcoma (Krib-1) into the L-3 vertebral body of nude mice via a drill hole. Motor function was evaluated daily using the previously validated qualitative key milestones of tail dragging, dorsal stepping, hindlimb sweeping, and paralysis. A subset of these animals was euthanized upon reaching the various milestones, and the spines were removed, sectioned, and stained. The degree of spinal cord compression was correlated with the occurrence of milestones and assessed by a ratio between the neural elements divided by the area of the spinal canal. Another subset of animals received stably transfected Krib-1 cells with the luciferase gene, and bioluminescence was measured at 10, 20, and 30 days postimplantation. RESULTS: Osteosarcoma xenografts grew in all animals according to a reliable and reproducible time course; the mean time for development of behavioral milestones was noted in relation to the day of implantation (Day 1). Tail dragging (Milestone 1) occurred on Day 19.06 (95% CI 16.11-22.01), dorsal stepping (Milestone 2) occurred on Day 28.78 (95% CI 26.79-30.77), hindlimb sweeping (Milestone 3) occurred on Day 35.61 (95% CI 32.9-38.32), and paralysis of the hindlimb (Milestone 4) occurred on Day 41.78 (95% CI 39.31-44.25). These clinically observed milestones correlated with increasing compression of the spinal cord on histological sections. The authors observed a progressive increase in the local bioluminescence (in photons/cm²/sec) of the implanted level over time with a mean of 2.17 (range 0.0-8.61) at Day 10, mean 4.68 (range 1.17-8.52) at Day 20, and mean 5.54 (range 1.22-9.99) at Day 30. CONCLUSIONS: The authors have developed the first orthotopic murine model of a primary malignant bone tumor in the spine, in which neurological decline reproducibly correlates with tumor progression as evidenced by pathological confirmation and noninvasive bioluminescence measurements. Although developed for osteosarcoma, this model can be expanded to study other types of primary malignant bone tumors in the spine. This model will potentially allow animal testing of targeted therapies against specific primary malignant tumor types.

Quality-of-life outcomes with minimally invasive transforaminal lumbar interbody fusion based on long-term analysis of 304 consecutive patients.

STUDY DESIGN: This was a prospective clinical study that took place in an outpatient spine clinic. OBJECTIVE: To demonstrate the short-/long-term outcomes from a large cohort of patients undergoing minimally invasive transforaminal lumbar interbody fusion (MITLIF). SUMMARY OF BACKGROUND DATA: Long-term prospective outcomes in patients undergoing minimally invasive spinal fusion for debilitating back pain has not been well studied. METHODS: Presenting diagnosis was determined from clinical findings and radiographical (radiograph, magnetic resonance image, computed tomographic scan) evaluations preoperatively. Patients were assessed with outcome measures preoperatively, and postoperatively at 2 weeks, 3 months, 6 months, 12 months, 24 months, and annually 2 to 7 years (mean follow-up: 47 mo) final follow-up. The rate of postoperative complications and reoperations at the initial level of MITLIF and adjacent level(s) were followed. Fusion rates were assessed blinded and independently by radiograph. RESULTS: Visual analogue scale scores decreased significantly from 7.0 preoperatively to 3.5 at mean 47-month follow-up. Oswestry Disability Index scores declined from 43.1 preoperatively to 28.2 at mean 47-month follow-up. Short-Form 36 mental component scores increased from 43.8 preoperatively to 49.7 at 47-month follow-up. Short-Form 36 physical component scores increased from 30.6 preoperatively to 39.6 at 47-month follow-up (P < 0.05). CONCLUSION: This prospectively collected outcomes study shows long-term statistically significant clinical outcomes improvement after MITLIF in patients with clinically symptomatic spondylolisthesis and degenerative disc disease with or without stenosis. MITLIF resulted in a high rate of spinal fusion and very low rate of interbody fusion failure and/or adjacent segment disease requiring reoperation while reducing postoperative complications. LEVEL OF EVIDENCE: 3.