Pain After Anterior Vertebral Body Tethering: Incidence, Risk Factors, and Timing.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To examine the incidence and risk factors for postoperative pain following anterior vertebral body tethering (AVBT) for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Up to 78% of patients with AIS report preoperative pain; it is the greatest patient concern surrounding surgery. Pain significantly decreases following posterior spinal fusion, but pain following AVBT is poorly understood. MATERIALS AND METHODS: We retrospectively reviewed 279 patients with a two-year follow-up after AVBT for AIS. We collected demographic, radiographic, and clinical data pertinent to postoperative pain at each time interval of preoperative and postoperative visits (6 wk, 6 mo, 1 y, and annually thereafter). RESULTS: Within our cohort, 68.1% of patients reported preoperative pain. Older age ( P =0.014) and greater proximal thoracic ( P =0.013) and main thoracic ( P =0.002) coronal curve magnitudes were associated with preoperative pain. Pain at any time point > 6 weeks postoperatively was reported in 41.6% of patients; it was associated with the female sex ( P =0.032), need for revision surgery ( P =0.019), and greater lateral displacement of the apical lumbar vertebrae ( P =0.028). The association between preoperative and postoperative pain trended toward significance ( P =0.07). At 6 months postoperatively, 91.8% had pain resolution; the same number remained pain-free at the time of last follow-up. The presence of a postoperative complication was associated with new-onset postoperative pain that resolved ( P =0.009). Only 8.2% had persistent pain, although no risk factors were found to be associated with persistent pain. CONCLUSION: In our cohort of 279 patients with a minimum 2-year follow-up after AVBT, 68.1% reported preoperative pain. Nearly 42% reported postoperative pain at any time point, but only 8.2% had persistent pain. Postoperative pain after AVBT was associated with female sex, revision surgery, and Lenke lumbar modifier. AVBT is associated with a significant reduction in pain, and few patients report long-term postoperative pain.

Autofusion With Magnetically Controlled Growing Rods: A Case Report.

Magnetically controlled growing rods (MCGRs) are an effective alternative to traditional growing rods (TGRs) in the treatment of early-onset scoliosis (EOS), with comparable deformity correction despite fewer planned reoperations. This case report presents a unique case of autofusion in a patient with tetraplegic cerebral palsy, thoracic myelomeningocele, and EOS who was treated with dual MCGR instrumentation and underwent serial lengthening procedures for four years. We detail the operative and radiographic findings in a novel case of autofusion encountered after MCGR placement to treat EOS. An eight-year-old female with tetraplegic cerebral palsy causing a 94° right thoracic neuromuscular scoliosis was treated with dual MCGRs; she then underwent serial lengthenings every four months. At 12 years of age, during MCGR explantation and posterior spinal fusion, dense heterotopic autofusion was encountered around the MCGR instrumentation, limiting further deformity correction. The benefits of MCGRs make them an appealing alternative to TGRs for the treatment of EOS. Although the theoretical risk of autofusion in MCGRs is low, recent case reports propose autofusion as a possible reason for MCGRs' failure to lengthen.

What Happens After a Vertebral Body Tether Break? Incidence, Location, and Progression With Five-year Follow-up.

STUDY DESIGN: Retrospective review. OBJECTIVE: To study risk factors for anterior vertebral body tether (VBT) breakage. SUMMARY OF BACKGROUND DATA: VBT is used to treat adolescent idiopathic scoliosis in skeletally immature patients. However, tethers break in up to 48% of cases. MATERIALS AND METHODS: We reviewed 63 patients who underwent thoracic and/or lumbar VBT with a minimum five-year follow-up. We radiographically characterized suspected tether breaks as a change in interscrew angle >5°. Demographic, radiographic, and clinical risk factors for presumed VBT breaks were evaluated. RESULTS: In confirmed VBT breaks, the average interscrew angle change was 8.1°, and segmental coronal curve change was 13.6°, with a high correlation ( r =0.82). Our presumed VBT break cohort constituted 50 thoracic tethers, four lumbar tethers, and nine combined thoracic/lumbar tethers; the average age was 12.1±1.2 years and the mean follow-up was 73.1±11.7 months. Of 59 patients with thoracic VBTs, 12 patients (20.3%) had a total of 18 breaks. Eleven thoracic breaks (61.1%) occurred between two and five years postoperatively, and 15 (83.3%) occurred below the curve apex ( P <0.05). The timing of thoracic VBT breakage moderately correlated with more distal breaks ( r =0.35). Of 13 patients who underwent lumbar VBT, eight patients (61.5%) had a total of 12 presumed breaks. Six lumbar breaks (50%) occurred between one and two years postoperatively, and seven (58.3%) occurred at or distal to the apex. Age, sex, body mass index, Risser score, and curve flexibility were not associated with VBT breaks, but the association between percent curve correction and thoracic VBT breakage trended toward significance ( P =0.054). Lumbar VBTs were more likely to break than thoracic VBTs ( P =0.016). Seven of the patients with presumed VBT breaks (35%) underwent revision surgery. CONCLUSIONS: Lumbar VBTs broke with greater frequency than thoracic VBTs, and VBT breaks typically occurred at levels distal to the curve apex. Only 15% of all patients required revision. LEVEL OF EVIDENCE: 3.

The use of intra-operative navigation during complex lumbar spine surgery under spinal anesthesia.

BACKGROUND: Spinal anesthesia is a safe and effective alternative to general anesthesia in both simple and complex lumbar surgery with numerous reported advantages leading to increased recent utilization. One potential barrier to the use of spinal anesthesia in lumbar surgery is the popularity of intraoperative computed tomography (CT) imaging. Intraoperative CT necessitates motionless patients and adds time to procedures, issues that may make surgeons hesitant to use concomitant spinal anesthesia. To date, the use of both techniques simultaneously has not been well described. OBJECTIVE: We propose that single-level lumbar fusions utilizing intraoperative CT scan acquisition and navigated instrumentation are feasible under single-dose spinal anesthesia without detrimental effect on image quality and navigation accuracy or need for spinal anesthetic re-dosing due to the additional time necessary. METHODS: We describe operative characteristics and intra-operative timing for our first five cases of transforaminal lumbar interbody fusion (TLIF) completed with intraoperative CT scan acquisition and navigated instrumentation performed under spinal anesthesia. RESULTS: The five patients ranged in age from 59 to 79 years, with an average body mass index of 27.0 kg/m2. The average total operative time for each surgery 109.2 min, including approximately 6.3 min required for CT scan acquisition. There were no complications and post-operative imaging demonstrated no malpositioned pedicle screws. CONCLUSION: Single-level TLIF procedures utilizing intraoperative CT acquisition and navigated instrumentation can be feasibly completed under single-dose spinal anesthesia without need for intraoperative apneic periods and without deleterious effect on instrumentation accuracy.

Post-operative quadriparesis following posterior cervical laminectomy and fusion: A case-series of incidence, risk factors, and management.

OBJECTIVE: Post-operative quadriparesis following posterior cervical decompression and fusion is a rare but devastating complication. Unless rapidly identified and treated, it can cause permanent injury and disability. Given the sparse literature on this topic we intend to report on its incidence, to identify potential predisposing risk factors, and to discuss management considerations. METHODS: We retrospectively reviewed a series of 301 patients who underwent posterior cervical decompressive laminectomies and instrumented fusion performed by the senior author between 2006 and 2020. We describe the clinical courses and interventions for the seven of these 301 patients who developed post-operative quadriparesis. RESULTS: The incidence of post-operative quadriparesis following cervical spine decompressive laminectomies and instrumented fusion was 2.3% (7/301) in our study. The mean time-to-onset was 2 days, and the most common pathology was post-operative hematoma. We did not identify any statistically significant risk factors that predispose patients to post-operative quadriparesis. In our series, the patients with post-operative quadriparesis without profound hypotension who underwent emergent surgical decompression demonstrated improved neurologic outcomes compared to those who underwent interval imaging prior to decompression. CONCLUSION: Post-operative quadriparesis following cervical spine surgery is a catastrophic complication that is poorly reported and under-studied in current literature. In this study, we found a 2.3% incidence of post-operative quadriparesis with no obvious risk factors predisposing patients to this adverse outcome. We advocate that post-operative quadriparesis following cervical spine surgery, in the absence of profound hypotension, warrants emergent surgical site exploration without delay for interval imaging.

Spinal anesthesia in contemporary and complex lumbar spine surgery: experience with 343 cases.

OBJECTIVE: Spinal anesthesia (SA) is an alternative to general anesthesia (GA) for lumbar spine surgery, including complex instrumented fusion, although there are relatively few outcome data available. The authors discuss their experience using SA in a modern complex lumbar spine surgery practice to describe its utility and implementation. METHODS: Data from patients receiving SA for lumbar spine surgery by one surgeon from March 2017 to December 2020 were collected via a retrospective chart review. Cases were divided into nonfusion and fusion procedure categories and analyzed for demographics and baseline medical status; pre-, intra-, and postoperative events; hospital course, including Acute Pain Service (APS) consults; and follow-up visit outcome data. RESULTS: A total of 345 consecutive lumbar spine procedures were found, with 343 records complete for analysis, including 181 fusion and 162 nonfusion procedures and spinal levels from T11 through S1. The fusion group was significantly older (mean age 65.9 ± 12.4 vs 59.5 ± 15.4 years, p < 0.001) and had a significantly higher proportion of patients with American Society of Anesthesiologists (ASA) Physical Status Classification class III (p = 0.009) than the nonfusion group. There were no intraoperative conversions to GA, with infrequent need for a second dose of SA preoperatively (2.9%, 10/343) and rare preoperative conversion to GA (0.6%, 2/343) across fusion and nonfusion groups. Rates of complications during hospitalization were comparable to those seen in the literature. The APS was consulted for 2.9% (10/343) of procedures. An algorithm for the integration of SA into a lumbar spine surgery practice, from surgical and anesthetic perspectives, is also offered. CONCLUSIONS: SA is a viable, safe, and effective option for lumbar spine surgery across a wide range of age and health statuses, particularly in older patients and those who want to avoid GA. The authors' protocol, based in part on the largest set of data currently available describing complex instrumented fusion surgeries of the lumbar spine completed under SA, presents guidance and best practices to integrate SA into contemporary lumbar spine practices.

C1-2 cyst presenting with syringobulbia: a case report.

Extradural atlantoaxial cysts are typically related to C1-2 degeneration. Intradural cysts may cause secondary syringobulbia depending on the size and cerebrospinal fluid flow obstruction. However, medullary syrinxes have not been previously described with extradural cysts. Treatment of symptomatic lesions involves surgical resection, often via a far-lateral approach, with consideration of fusion if C1-2 instability is present. We present a case of an extradural C1-2 cyst with intradural extension causing syringobulbia. Effective surgical resection was accomplished via a far-lateral, partial transcondylar approach without fusion. It is important to recognize that cysts of extradural origin may exhibit intradural extension and compress critical neurovascular structures.

Left Parietal Tumors Presenting with Smartphone Icon Visual Agnosia: Two Cases of a Modern Presentation of Gerstmann Syndrome.

BACKGROUND: Gerstmanns syndrome-a clinical constellation of left-right confusion, finger agnosia, agraphia, and acalculia-is frequently attributed to pathology in the dominant inferior parietal lobe or temporo-occipital region. However, these unique clinical findings are often accompanied by more subtle signs, including aphasias, neglect, and agnosias. Associative visual agnosia, in which a patient is able to accurately perceive and describe but not recognize an object or symbol, is a well-documented but infrequently observed clinical entity. CASE DESCRIPTION: Here we detail 2 unique cases of patients who presented with the inability to recognize and use smartphone application icons. Both were found to have left temporo-occipital tumors displacing the left temporo-parietooccipital cortex. CONCLUSIONS: In the era of pervasive technology, we emphasize that smartphone icon associative visual agnosias may be recognized by discerning physicians in the clinical diagnosis of dominant parietal lobe pathology.

Tumor-to-Tumor Metastasis of Hepatocellular Carcinoma to Vestibular Schwannoma.

BACKGROUND: Intracranial metastasis is a common complication of systemic malignancy. A rare subset of intracranial masses constitutes tumor-to-tumor metastasis, in which an extracranial neoplasm hematogenously spreads to an existing intracranial lesion. CASE DESCRIPTION: Here we present the unique case of a 59-year-old man with known hepatocellular carcinoma who presented with acute headaches, double vision, vertigo, and gait instability in the context of 2 years of right-sided hearing loss. Head imaging showed a heterogeneous right cerebellopontine angle mass extending into the porus acousticus with adjacent cerebellar edema. Histopathologic analysis after resection found coexisting hepatocellular carcinoma within a vestibular schwannoma. CONCLUSIONS: Tumor-to-tumor metastasis is an important consideration in the diagnostic work-up and treatment of patients with known systemic malignancy who present with a new intracranial lesion. This pathologic entity could be missed if this patient were treated with single-fraction radiosurgery such as Gamma Knife.

Intracranial Ewing sarcoma: four pediatric examples.

BACKGROUND: Ewing sarcoma typically arises in bone and is unrelated to intraparenchymal small blue cell embryonal central nervous system (CNS) tumors previously designated primitive neuroectodermal tumors (PNETs). When the CNS is impacted, it is usually secondary to local extension from either the epidural space, skull, or intracranial or spinal metastases. Primary examples within the cranial vault are rare, usually dural-based, and are largely case reports in the literature. We detail four pediatric patients with solitary, primary intracranial Ewing sarcoma, all manifesting the archetypal EWRS1 gene rearrangement that confirms diagnosis. PROCEDURE: Neurosurgical Department records, spanning 21 years (1995-2016), were reviewed to identify patients. Demographics, clinical history, pathological/genetic features, and clinical course were retrieved from the medical record and personal files of the authors. RESULTS: Four patients, one male and three females, age 5 to 16 years, were identified. One presented in extremis from a large lesion, two with soft tissue masses, and the fourth as an incidental finding after being involved in a motor vehicle collision. Three had clear bony involvement: a 10-year-old girl with a large left temporal lesion had clear origin in the skull, with spiculated calcified striations throughout the mass; a 9-year-old girl presented with a bony left petrous apex mass; and a 16-year-old girl presented with a left temporal mass with extension to the dura and underlying bone erosion. Only the 5-year-old boy had a large left frontoparietal mass traversing the falx with no bony contact. All four tumors manifested the diagnostic EWSR1 mutation and were treated with an Ewing sarcoma regimen. Outcomes were variable, with one patient showing progressive metastatic disease and death 3 years after presentation, one patient with disease-free survival 10.5 years after completion of therapy, and one alive and well at the completion of therapy 1 year after diagnosis. One patient completed therapy recently with post-therapy scans showing no evidence of disease. CONCLUSION: Testing for the EWSR1 mutation confirms the diagnosis of Ewing sarcoma and excludes other types of embryonal CNS tumors. Long-term disease-free survival is possible with adherence to the appropriate therapeutic regimen after gross surgical resection.

Isolated Great Saphenous Vein Thrombus Is Associated with High Rates of Complications regardless of Management.

BACKGROUND: Isolated great saphenous vein thrombus (GSVT) is generally regarded as benign, and treatment is heterogeneous. Complications include thrombus propagation, new saphenous vein thrombosis, deep vein thrombosis (DVT), pulmonary embolism (PE), and symptom persistence. Our objective was to review our institution's experience with isolated GSVT to understand its natural history, the frequency of complications, real-world treatment, and the impact of proximity to the saphenofemoral junction (SFJ), on the rate of complications. METHODS: Records of patients who had lower extremity venous duplex (LEVD) demonstrating GSVT without concomitant DVT between July 2008 and June 2014 were reviewed. Demographic, medical, management, outcomes, and follow-up LEVD data were collected. RESULTS: Of 605 patients with acute GSVT, 67 limbs in 61 patients with isolated GSVT were the study group; 14.8% of patients had a hypercoagulable state, 31.1% had prior GSVT or DVT, and 23.0% of patients had malignancy; 28.4% of GSVT were observed, 13.4% were treated with aspirin/NSAIDs, and 58.2% were anticoagulated; 38.8% of limbs remained symptomatic following treatment at a mean follow-up period of 761 days; 37 limbs had GSVT <5 cm of the SFJ (group 1), and 30 had GSVT >5 cm from the SFJ (group 2). Seven patients developed PE, all in group 1 (P = 0.02). Twenty-nine limbs (43.3%) had follow-up LEVD at a mean of 23 days. In this subset, 13 patients at the initial scan (44.8%) had thrombus <5 cm of the SFJ (group 1) and 16 (55.2%) had thrombus >5 cm from the SFJ (group 2). Five limbs (17.2%) had GSVT propagation/new superficial vein thrombosis (SVT), and 6 (20.7%) developed new DVT. There was no GSVT propagation/new SVT in group 1, whereas 5 limbs (31.2%) had GSVT propagation/new SVT in group 2 (P = 0.048). DVT occurred in 2 limbs (15.3%) in group 1 and 4 limbs (25%) in group 2. CONCLUSIONS: Isolated GSVT tends to affect patients with hypercoagulable states, prior venous thromboembolism, malignancy, or recent surgery. Management is heterogeneous, and type of treatment does not seem to affect outcomes. Patients with GSVT have significant risk of persistent symptoms, recurrence, DVT, and PE. GSVT within 5 cm of the SFJ seemed to be associated with an increased rate of PE. GSVT more than 5 cm from the SFJ seemed to be associated with propagation/new SVT. Proximity to the SFJ did not impact occurrence of DVT.