Distance to first symptoms measured by the 6-min walking test differentiates between treatment success and failure in patients with degenerative lumbar disorders.

PURPOSE: The smartphone-based 6-min walking test (6WT) is an established digital outcome measure in patients undergoing surgery for degenerative lumbar disorders (DLD). In addition to the 6WTs primary outcome measure, the 6-min walking distance (6WD), the patient's distance to first symptoms (DTFS) and time to first symptoms (TTFS) can be recorded. This is the first study to analyse the psychometric properties of the DTFS and TTFS. METHODS: Forty-nine consecutive patients (55 ± 15.8 years) completed the 6WT pre- and 6 weeks (W6) postoperative. DTFS and TTFS were assessed for reliability and content validity using disease-specific patient-reported outcome measures. The Zurich Claudication Questionnaire patient satisfaction subscale was used as external criterion for treatment success. Internal and external responsiveness for both measures at W6 was evaluated. RESULTS: There was a significant improvement in DTFS and TTFS from baseline to W6 (p < 0.001). Both measures demonstrated a good test-retest reliability (ß = 0.86, 95% CI 0.81-0.90 and ß = 0.83, 95% CI 0.76-0.87, both p < 0.001). The DTFS exceeded the 6WD capability to differentiate between satisfied (82%) and unsatisfied patients (18%) with an AUC of 0.75 (95% CI 0.53-0.98) vs. 0.70 (95% CI 0.52-0.90). The TTFS did not demonstrate meaningful discriminative abilities. CONCLUSION: Change in DTFS can differentiate between satisfied and unsatisfied patients after spine surgery. Digital outcome measures on the 6WT metric provide spine surgeons and researchers with a mean to assess their patient's functional disability and response to surgical treatment in DLD.

Longitudinal smartphone-based self-assessment of objective functional impairment in patients undergoing surgery for lumbar degenerative disc disease: initial experience.

BACKGROUND: The worldwide spread of smartphone usage enables new possibilities for longitudinal monitoring of objective functional impairment (OFI) in patients undergoing surgery for lumbar degenerative disc disease (DDD). METHODS: Three patients, undergoing elective surgery for lumbar DDD, self-assessed OFI using a recently validated 6-min walking test (6WT) smartphone application. Results are presented as raw 6-min walking distance (6WD) as well as in reference to age- and sex-specific healthy population reference values using standardized z-scores (number of standard deviations). In parallel, patient-reported outcome measures (PROMs), including numeric rating scale (NRS) leg-pain and Core Outcome Measures Index (COMI) were obtained before (pre) and 6 weeks (6 W) as well as 3 months (3 M) after surgery. Descriptive analyses were used to compare PROMs with repeated 6WT measurements over time. The feasibility and benefits of the longitudinal OFI measurements using the 6WT app are discussed. RESULTS: One patient presented a favorable outcome, reflected by a clinically meaningful improvement in PROMs. Correspondingly, the 6WT distance gradually improved above the normal population values ((pre 399 m (z-score - 1.96) vs. 6 W 494 m (- 0.85) vs. 3 M 557 m (- 0.1)). One patient experienced initial improvement at 6 W, followed by a decline in 6WD at 3 M which promoted further interventions with subsequent recovery ((358 m (z-score - 3.29) vs 440 m (- 2.2) vs 431 m (- 2.32) vs 471 m (- 1.78)). The last patient showed a lack of improvement in PROMs as well as in OFI (360 m (z-score 0.0) vs 401 m (0.30) vs 345 m (- 0.11)) resulting in secondary surgery. CONCLUSION: The longitudinal assessment of OFI using the 6WT app was feasible and provided the physician with a detailed history of patients' postoperative walking capacity complementing commonly used PROMs.

Sexual and urinary function following anterior lumbar surgery in females.

AIMS: Anterior lumbar interbody fusion procedures (ALIF) and total disc replacement (TDR) with anterior exposure of the lumbar spine entail a risk of a vascular injury and dysfunction of the sympathetic and parasympathetic nerves due to disturbance of the inferior and superior hypogastric plexus. While retrograde ejaculation is a known complication of the anterior spinal approach in males, post-operative sexual as well as urinary function in females has not yet been thoroughly investigated and was hence the aim of this study. METHODS: Fifteen female patients documented their sexual and urinary function preoperatively, 3 months and 6 months postoperatively, using the validated questionnaires FSFI (Female Sexual Function Index) and ICIQ (International Consultation of Incontinence Questionnaire). Randomization tests were used to statistically analyze expectation values over time (two-sided, P < 0.05). RESULTS: While no statistically significant change in the total FSFI score occurred over time, a significant increase in FSFI desire score was noted between preoperative (2.95 ± 0.8) and 6 months follow-up (3.51 ± 0.6, P = 0.02). Urinary continence remained unchanged over time. CONCLUSION: In summary, ALIF and lumbar TDR do not seem to negatively influence sexual and urinary function in females. In contrast, increased sexual desire was noted, likely secondary to post-surgical pain relief.

Association of single and multiple aneurysms with tobacco abuse: an @neurIST risk analysis.

OBJECTIVE: Although several studies have suggested that the incidence of intracranial aneurysms (IAs) is higher in smokers, the higher prevalence of subarachnoid hemorrhage (SAH) in smokers remains uncertain. It is unclear whether smoking additionally contributes to the formation of multiple aneurysms and the risk of rupture. The aim of this study was to determine whether smoking is associated with IA formation, multiplicity, or rupture. METHODS: Patients from the prospective multicenter @neurIST database (n = 1410; 985 females [69.9%]) were reviewed for the presence of SAH, multiple aneurysms, and smoking status. The prevalence of smokers in the population of patients diagnosed with at least one IA was compared with that of smokers in the general population. RESULTS: The proportion of smokers was higher in patients with IAs (56.2%) than in the reference population (51.4%; p < 0.001). A significant association of smoking with the presence of an IA was found throughout group comparisons (p = 0.01). The presence of multiple IAs was also significantly associated with smoking (p = 0.003). A trend was found between duration of smoking and the presence of multiple IAs (p = 0.057). However, the proportion of smokers among patients suffering SAH was similar to that of smokers among patients diagnosed with unruptured IAs (p = 0.48). CONCLUSIONS: Smoking is strongly associated with IA formation. Once an IA is present, however, smoking does not appear to increase the risk of rupture compared with IAs in the nonsmoking population. The trend toward an association between duration of smoking and the presence of multiple IAs stresses the need for counseling patients with IAs regarding lifestyle modification.

Objective functional assessment using the "Timed Up and Go" test in patients with lumbar spinal stenosis.

OBJECTIVEPatient-reported outcome measures (PROMs) are standard of care for the assessment of functional impairment. Subjective outcome measures are increasingly complemented by objective ones, such as the "Timed Up and Go" (TUG) test. Currently, only a few studies report pre- and postoperative TUG test assessments in patients with lumbar spinal stenosis (LSS).METHODSA prospective two-center database was reviewed to identify patients with LSS who underwent lumbar decompression with or without fusion. The subjective functional status was estimated using PROMs for pain (visual analog scale [VAS]), disability (Roland-Morris Disability Index [RMDI] and Oswestry Disability Index [ODI]), and health-related quality of life (HRQoL; 12-Item Short-Form Physical Component Summary [SF-12 PCS] and the EQ-5D) preoperatively, as well as on postoperative day 3 (D3) and week 6 (W6). Objective functional impairment (OFI) was measured using age- and sex-standardized TUG test results.RESULTSSixty-four patients (n = 32 [50%] male, mean age 66.8 ± 11.7 years) were included. Preoperatively, they reported a mean VAS back pain score of 4.1 ± 2.7, VAS leg pain score of 5.4 ± 2.7, RMDI of 10.4 ± 5.3, ODI of 41.9 ± 16.2, SF-12 PCS score of 32.7 ± 8.3, and an EQ-5D index of 0.517 ± 0.226. The preoperative rates of severe, moderate, and mild OFI were 4.7% (n = 3), 12.5% (n = 8), and 7.8% (n = 5), respectively, and the mean OFI T-score was 116.3 ± 23.7. At W6, 60 (93.8%) of 64 patients had a TUG test result within the normal population range (no OFI); 3 patients (4.7%) had mild and 1 patient (1.6%) severe OFI. The mean W6 OFI T-score was significantly decreased (103.1 ± 13.6; p < 0.001). Correspondingly, the PROMs showed a decrease in subjective VAS back pain (1.6 ± 1.7, p < 0.001) and leg pain (1.0 ± 1.8, p < 0.001) scores, disability (RMDI 5.3 ± 4.7, p < 0.001; ODI 21.3 ± 16.1, p < 0.001), and increase in HRQoL (SF-12 PCS 40.1 ± 8.3, p < 0.001; EQ-5D 0.737 ± 0.192, p < 0.001) at W6. The W6 responder status (clinically meaningful improvement) ranged between 81.3% (VAS leg pain) and 29.7% (EQ-5D index) of patients.CONCLUSIONSThe TUG test is a quick and easily applicable tool that reliably measures OFI in patients with LSS. Objective tests incorporating longer walking time should be considered if OFI is suspected but fails to be proven by the TUG test, taking into account that neurogenic claudication may not clinically manifest during the brief TUG examination. Objective tests do not replace the subjective PROM-based assessment, but add valuable information to a comprehensive patient evaluation.

Central nervous system microbleeds in the acute phase are associated with structural integrity by DTI one year after mild traumatic brain injury: A longitudinal study.

INTRODUCTION: Several imaging modalities are under investigation to unravel the pathophysiological mystery of delayed performance deficits in patients after mild traumatic brain injury (mTBI). Although both imaging and neuropsychological studies have been conducted, only few data on longitudinal correlations of diffusion tensor imaging (DTI), susceptibility weighted imaging (SWI) and extensive neuropsychological testing exist. METHODS: MRI with T1- and T2-weighted, SWI and DTI sequences at baseline and 12 months of 30 mTBI patients were compared with 20 healthy controls. Multiparametric assessment included neuropsychological testing of cognitive performance and post-concussion syndrome (PCS) at baseline, 3 and 12 months post-injury. Data analysis encompassed assessment of cerebral microbleeds (Mb) in SWI, tract-based spatial statistics (TBSS) and voxel-based morphometry (VBM) of DTI (VBM-DTI). Imaging markers were correlated with neuropsychological testing to evaluate sensitivity to cognitive performance and post-concussive symptoms. RESULTS: Patients with Mb in SWI in the acute phase showed worse performance in several cognitive tests at baseline and in the follow-ups during the chronic phase and higher symptom severity in the post concussion symptom scale (PCSS) at twelve months post-injury. In the acute phase there was no statistical difference in structural integrity as measured with DTI between mTBI patients and healthy controls. At twelve months post-injury, loss of structural integrity in mTBI patients was found in nearly all DTI indices compared to healthy controls. CONCLUSIONS: Presence of Mb detected by SWI was associated with worse cognitive outcome and persistent PCS in mTBI patients, while DTI did not prove to predict neuropsychological outcome in the acute phase.

The usefulness of radiological grading scales to predict pain intensity, functional impairment, and health-related quality of life after surgery for lumbar degenerative disc disease.

PURPOSE: The goal of this study is to determine the relationship of radiological grading scales of lumbar degenerative disc disease (DDD) with postoperative pain intensity, functional impairment, and health-related quality of life (HRQoL). METHODS: Response to surgical treatment at 6 weeks (W6) on the visual analogue scale (VAS) for back and leg pain, Oswestry-Disability (ODI) and Roland-Morris Disability Index (RMDI), Timed Up and Go (TUG) test, EuroQol (EQ) 5D, and Short-Form Health-Survey (SF-12) physical component summary (PCS) was compared between patients with different Modic (MOD) and Pfirrmann (PFI) grades. Longitudinal outcomes at day 3 (D3), W6, 6 months (M6), and 1 year (Y1) were compared. RESULTS: The study included 338 patients (mean age, 58.6 years), of which n = 202 (59.8%) had MOD 1-3 and n = 217 (64.2%) PFI 4-5 changes. Patients with MOD 1-3 were as likely as patients without MOD changes to be treatment-responders at W6 in terms of VAS leg pain, ODI, RMDI, TUG, EQ5D, and SF-12 PCS. Similarly, patients with PFI 4-5 were as likely as patients with PFI 1-3 changes to be treatment-responders at W6. Longitudinal outcomes were similar at D3, W6, M6, and Y1 between patients with and without MOD changes. Patients with PFI 4-5 fared similar to those with PFI 1-3 except for inferior HRQoL on the SF-12 PCS metric at Y1. CONCLUSIONS: There was no distinct relationship between commonly used radiological grading scales of lumbar DDD with clinical outcome. Therefore, no prognosis should be made on the grounds of preoperative PFI and MOD classifications for patients undergoing spine surgery for lumbar DDD.

Three versus seven days to return-to-work after mild traumatic brain injury: a randomized parallel-group trial with neuropsychological assessment.

Although most patients with a mild traumatic brain injury (mTBI) recover within days to weeks, some experience persistent physical, cognitive and emotional symptoms, often described as post-concussion syndrome (PCS). The optimal recovery time including return-to-work (RTW) after mTBI is unclear. In this single-centre parallel-group trial, patients assigned three days (3D-group) or seven days (7D-group) sick leave were compared with a comprehensive neuropsychological test battery including the Post-Concussion Symptom Scale (PCSS) within one week, after three and 12 months post-injury. The influence of the effective time until RTW on post-concussional symptoms and cognitive performance was analysed. The 3D-group rated significantly higher mean scores in some PCSS symptoms, tended to fulfil diagnosis criteria of PCS more often and showed better cognitive performance in several neuropsychological test scores than the 7D-group at all three time-points of follow-up. Overall, patients returned to work 11.35 d post-injury, thus distinctly above both recommended sick leaves. There was a trend for longer sick leave in patients randomized into the 3D-group. Further analyses revealed that the group with an absolute RTW within one week showed lower symptom severity in fatigue at 3 and 12 months, less PCS and faster performance in fine motor speed at 12 months than the group with an absolute RTW after one week. Our data underline the heterogeneity of mTBI and show that acute and sub-acute symptoms are not prognostic factors for neuropsychological outcome at one year. Later, ability to work seems to be prognostic for long-term occurrence of PCS.

Pre- and postoperative correlation of patient-reported outcome measures with standardized Timed Up and Go (TUG) test results in lumbar degenerative disc disease.

BACKGROUND: The Timed Up and Go (TUG) test is a reliable tool for evaluating objective functional impairment (OFI) in patients with degenerative disc disease before a surgical intervention. The aim of this study is to assess the validity of the TUG test to measure change in function postoperatively. METHODS: In a prospective two-center study, OFI was assessed by the TUG test in patients scheduled for lumbar spine surgery, as well as 3 days (D3) and 6 weeks (W6) postoperatively. At each time point, the TUG test results were correlated with established subjective measures of pain intensity (visual analogue scale (VAS) for back and leg pain), functional impairment (Oswestry Disability Index (ODI)) and health-related quality of life (HRQoL; Short Form-12 (SF12)). RESULTS: The patient cohort comprised 136 patients with a mean age of 57.7 years; 76 were males, 54 had a microdiscectomy for lumbar disc herniation, 58 a decompression for a lumbar spinal stenosis, 24 had a surgical fusion procedure. The mean OFI t-score was 125.1 before surgery, and as patients improved on the subjective measures in the postoperative interval, the OFI t-score likewise decreased to 118.8 (D3) and 103.4 (W6). The Pearson correlation coefficient (PCC) between the OFI t-score and VAS leg pain was 0.187 preoperatively (p = 0.029) and 0.252 at W6 (p = 0.003). The PCC between OFI t-score and the ODI was 0.324 preoperatively (p < 0.001) and 0.413 at W6 (p < 0.001). The PCC between OFI t-score and physical HRQoL (SF12) was -0.091 preoperatively (p = 0.293) and -0.330 at W6 (p < 0.001). CONCLUSIONS: The TUG test is sensitive to change, and reflects the postoperative functional outcome even more exact than preoperatively, as indicated by better correlation coefficients of the OFI t-score with subjective measures of pain intensity, functional impairment and HRQoL.

Residency program trainee-satisfaction correlate with results of the European board examination in neurosurgery.

INTRODUCTION: Substantial country differences in neurosurgical training throughout Europe have recently been described, ranging from subjective rating of training quality to objective working hours per week. The aim of this study was to analyse whether these differences translate into the results of the written and oral part of the European Board Examination in Neurological Surgery (EBE-NS). METHODS: Country-specific composite scores for satisfaction with quality of theoretical and practical training, as well as working hours per week, were obtained from an electronic survey distributed among European neurosurgical residents between June 2014 and March 2015. These were related to anonymous country-specific results of the EBE-NS between 2009 and 2016, using uni- and multivariate linear regression analysis. RESULTS: A total of n = 1025 written and n = 63 oral examination results were included. There was a significant linear relationship between the country-specific EBE-NS result in the written part and the country-specific composite score for satisfaction with quality of theoretical training [adjusted regression coefficient (RC) -3.80, 95 % confidence interval (CI) -5.43-7 -2.17, p < 0.001], but not with practical training or working time. For the oral part, there was a linear relationship between the country-specific EBE-NS result and the country-specific composite score for satisfaction with quality of practical training (RC 9.47, 95 % CI 1.47-17.47, p = 0.021), however neither with satisfaction with quality of theoretical training nor with working time. CONCLUSION: With every one-step improvement on the country-specific satisfaction score for theoretical training, the score in the EBE-NS Part 1 increased by 3.8 %. With every one-step improvement on the country-specific satisfaction score for practical training, the score in the EBE-NS Part 2 increased by 9.47 %. Improving training conditions is likely to have a direct positive influence on the knowledge level of trainees, as measured by the EBE-NS. The effect of the actual working time on the theoretical and practical knowledge of neurosurgical trainees appears to be insignificant.

Neurosurgical resident education in Europe--results of a multinational survey.

INTRODUCTION: Neurosurgical training aims at educating future generations of specialist neurosurgeons and at providing the highest-quality medical services to patients. Attaining and maintaining these highest standards constitutes a major responsibility of academic or other training medical centers. METHODS: An electronic survey was sent to European neurosurgical residents between 06/2014 and 03/2015. Multiple logistic regression analysis was used to assess the effect size of the relationship between responder-specific variables (e.g., age, gender, postgraduate year (PGY), country) and the outcomes (e.g., satisfaction). RESULTS: A total of 652 responses were collected, of which n = 532 were taken into consideration. Eighty-five percent were 26-35 years old, 76 % male, 62 % PGY 4 or higher, and 73.5 % working at a university clinic. Satisfaction rates with theoretical education such as clinical lectures (overall: 50.2 %), anatomical lectures (31.2 %), amongst others, differed largely between the EANS member countries. Likewise, satisfaction rates with practical aspects of training such as hands-on surgical experience (overall: 73.9 %), microsurgical training (52.5 %), simulator training (13.4 %), amongst others, were highly country-dependant. In general, 89.1 % of European residents carried out the first surgical procedure under supervision within the first year of training. Supervised lumbar-/cervical spine surgeries were performed by 78.2 and 17.9 % of European residents within 12 and 24 months of training, respectively, and 54.6 % of European residents operate a cranial case within the first 36 months of training. Logistic regression analysis identified countries where residents were much more or much less likely to operate as primary surgeons compared to the European average. The caseload of craniotomies per trainee (overall: 30.6 % ≥10 craniotomies/month) and spinal procedures (overall: 29.7 % ≥10 spinal surgeries/month) varied throughout the countries and was significantly associated with more advanced residency (craniotomy: OR 1.35, 95 % CI 1.18-1.53, p < 0.001; spinal surgery: OR 1.37, 95 % CI 1.20-1.57, p < 0.001). CONCLUSIONS: Theoretical and practical aspects of neurosurgical training are highly variable throughout European countries, despite some efforts within the last two decades to harmonize this. Some countries are rated significantly above (and others significantly below) the current European average for several analyzed parameters. It is hoped that the results of this survey should provide the incentive as well as the opportunity for a critical analysis of the local conditions for all training centers, but especially those in countries scoring significantly below the European average.

Working time of neurosurgical residents in Europe--results of a multinational survey.

INTRODUCTION: The introduction of the European Working Time directive 2003/88/EC has led to a reduction of the working hours with distinct impact on the clinical and surgical activity of neurosurgical residents in training. METHODS: A survey was performed among European neurosurgical residents between 06/2014 and 03/2015. Multiple logistic regression was used to assess the relationship between responder-specific variables (e.g., age, gender, country, postgraduate year (PGY)) and outcome (e.g., working time). RESULTS: A total of 652 responses were collected, of which n = 532 responses were taken into consideration. In total, 17.5, 22.1, 29.5, 19.5, 5.9, and 5.5 % of European residents indicated to work <40, 40-50, 51-60, 61-70, 71-80, or >80 h/week, respectively. Residents from France and Turkey (OR 4.72, 95 % CI 1.29-17.17, p = 0.019) and Germany (OR 2.06, 95 % CI 1.15-3.67, p = 0.014) were more likely to work >60 h/week than residents from other European countries. In total, 29 % of European residents were satisfied with their current working time, 11.3 % indicated to prefer reduced working time. More than half (55 %) would prefer to work more hours/week if this would improve their clinical education. Residents that rated their operative exposure as insufficient were 2.3 times as likely as others to be willing to work more hours (OR 2.32, 95 % CI 1.47-3.70, p < 0.001). Less than every fifth European resident spends >50 % of his/her working time in the operating room. By contrast, 77.4 % indicate to devote >25 % of their daily working time to administrative work. For every advanced PGY, the likelihood to spend >50 % of the working time in the OR increases by 19 % (OR 1.19, 95 % CI 1.02-1.40, p = 0.024) and the likelihood to spend >50 % of the working time with administrative work decreases by 18 % (OR 0.84, 95 % CI 0.76-0.94, p = 0.002). CONCLUSIONS: The results of this survey on >500 European neurosurgical residents clearly prove that less than 40 % conform with the 48-h week as claimed by the WTD2003/88/EC. Still, more than half of them would chose to work even more hours/week if their clinical education were to improve; probably due to subjective impression of insufficient training.

Diagnostic approaches to predict persistent post-traumatic symptoms after mild traumatic brain injury - a literature review.

Mild traumatic brain injury (mTBI) is one of the most frequently diagnosed neurological disorders in emergency departments. Although there are established recommendations for the diagnosis and treatment in the acute stage, there is an on-going debate in which diagnostic methods and risk factors predict unfavourable long-term outcome after mTBI. This literature review addresses the question, which diagnostic approaches may best predict persistent post-traumatic symptoms (pPTS). A literature search for experimental studies from January 2000 to September 2014 evaluating the following diagnostic approaches (1) susceptibility weighted imaging (SWI), (2) diffusion tensor imaging (DTI), (3) magnetic resonance spectroscopy (MRS), (4) functional magnetic resonance imaging (fMRI), as predictive factors of pPTS or unfavourable cognitive outcome in adult populations with mTBI was performed. DTI has been proved to be a valuable tool to identify diffuse axonal injury (DAI) after mTBI. Additionally, some studies showed associations between DAI and unfavourable cognitive outcome. SWI has shown to be a highly sensitive imaging method to identify microbleeds. The presence and quantity of microbleeds in this imaging technique can further provide aetiological evidence for pPTS. MRS provides information about local neurons metabolism and preliminary data show that creatine-phosphocreatine levels measured after mTBI are predictive of cognitive outcome and emotional distress. The results of one study have shown fMRI as a useful tool to differentiate mTBI patients with pPTS from controls and mTBI patients without pPTS in a resting-state condition. From the evaluated diagnostic approaches to predict pPTS after mTBI, DTI, SWI, MRS, and fMRI seem to have adequate sensitivity and specificity as predictive diagnostic tools for pPTS. Large longitudinal clinical trials are warranted to validate the prognostic applicability and practicability in daily clinical practice.

Extreme lateral interbody fusion (XLIF®): how I do it.

BACKGROUND: First introduced by Pimenta et al. in 2001, the extreme lateral interbody fusion (XLIF®) approach is a safe and effective alternative to anterior or posterior approaches to lumbar fusion, avoiding the large anterior vessels and posterior structures including the paraspinous muscles, facet joint complexes and tension bands. METHOD: The authors provide a detailed description of the surgically relevant anatomy focusing on the close relationship among the lumbar plexus, psoas muscle and lateral spinal column. The surgical technique is detailed step by step, stressing how to avoid complications. A video clip of an XLIF is provided, and important perioperative considerations are listed in detail. CONCLUSION: The XLIF® approach is a safe procedure allowing an approach to the lateral lumbar spine. Nevertheless, the surgeon's knowledge of anatomical landmarks, response to visual and tactile cues, and intraoperative decision-making skills remain of paramount importance. KEY POINTS: • Correct lateral positioning with an orthogonal orientation of the corresponding lumbar vertebral body is of key importance. • Subsequent table repositioning for every level is advised in multilevel cases. • Posterior structures including the paraspinous muscles, facet joint complexes and tension bands are mostly preserved. • Meticulous preoperative planning of the psoas docking point, considering all level-specific vascular and neuronal elements, is of paramount importance. • In general, concavity is recommended for the selection of the approach side. • A careful endplate and contralateral preparation and release are mandatory in order to allow bony fusion and maximum indirect foraminal decompression. • Using a perioperative dexamethasone bolus seems to be effective at the L4/5 level to reduce postoperative plexopathy. • Overdistraction should be avoided in order to prevent cage subsidence. • A major disadvantage is the relatively high, but mostly only transient, incidence of psoas weakness as well as hip-groin-thigh pain, dysaesthesia and/or numbness. • Major advantages include indirect neurological decompression, minimal blood loss, shorter operation times, decreased overall infection rates and more surface for bony fusion.

Anterior cervical discectomy and fusion: is surgical education safe?

BACKGROUND: Operative skills are key to neurosurgical resident training. They should be acquired in a structured manner and preferably starting early in residency. The aim of this study was to test the hypothesis that the outcome and complication rate of anterior cervical discectomy and fusion with or without instrumentation (ACDF(I)) is not inferior for supervised residents as compared to board-certified faculty neurosurgeons (BCFN). METHODS: This was a retrospective single-center study of all consecutive patients undergoing ACDF(I)-surgery between January 2011 and August 2014. All procedures were dichotomized into two groups according to the surgeon's level of experience: teaching cases (postgraduate year (PGY)-2 to PGY-6 neurosurgical residents) and non-teaching cases operated by BCFN. The primary study endpoint was patients' clinical outcome 4 weeks after surgery, categorized into a binary responder and non-responder variable. Secondary endpoints were complications, need for re-do surgery, and clinical outcome until the last follow-up. RESULTS: After exclusion of six cases because of incomplete data, a total of 287 ACDF(I) operations were enrolled into the study, of which 82 (29.2 %) were teaching cases and 199 (70.8 %) were non-teaching cases. Teaching cases required a longer operation time (131 min (95 % confidence interval (CI) 122-141 min) vs. 102 min (95-108 min; p < 0.0001) and were associated with a slightly higher estimated blood loss (84 ml (95 % CI 56-111 ml) vs. 57 ml (95 % CI 47-66 ml); p = 0.0017), while there was no difference in the rate of intraoperative complications (2.4 vs. 1.5 %; p = 0.631). Four weeks after surgery, 92.7 and 93 % of the patients had a positive response to surgery (p = 1.000), respectively. There was no difference in the postoperative complication rate (4.9 vs. 3.0 %; p = 0.307). Around 30 % of the study patients were followed up in outpatient clinics for more than once up until a mean period of 6.4 months (95 % CI 5.3-7.6 months). At the last follow-up, the clinical outcome was similar with a 90 % responder rate for both groups (p = 0.834). In total, five patients from the teaching group and eight patients from the non-teaching group required re-do surgery (p = 0.602). CONCLUSIONS: Short- and mid-term outcomes and complication rates following microscopic ACDF(I) were comparable for patients operated on by supervised neurosurgical residents or by senior surgeons. Our data thus indicate that a structured neurosurgical education of operative skills does not lead to worse outcomes or increase the complication rates after ACDF(I). Confirmation of the results by a prospective study is desired.

Incidental durotomy in lumbar spine surgery--a three-nation survey to evaluate its management.

BACKGROUND: Although it is generally accepted that incidental durotomies (ID) should be primarily repaired, the current literature shows no consensus regarding the peri- and postoperative management in case of ID during lumbar spine surgery. Because ID is a rather frequent complication and may be associated with significant disability, we were interested to analyze the current handling of ID in three European countries. METHODS: In March 2014, members of the Swiss, German, and Austrian neurosurgical and spine societies were asked to complete an online questionnaire regarding the management of ID during and after lumbar spine surgery. Two, respectively 4 weeks after the first invitation, reminder requests were sent to all invitees, who had not already responded at that time. RESULTS: There were 175 responses from 397 requests (44.1 %). Responders were predominantly neurosurgeons (89.7 %; 10.3 % were orthopedic surgeons), of which 45.7, 40.0, and 17.8 % work in a non-university hospital, university hospital, and private clinic, respectively. As for the perioperative management of ID, 19.4 % of the responders suggest only bed rest, while, depending on the extent of the ID, 84.0 % suggest additional actions, TachoSil/Spongostan with fibrin glue or a similar product and single suture repair being the most mentioned. Concerning epidural wound drainage in case of ID, 37.2 % desist from placing an epidural wound drainage with or without aspiration, 30.9 % place it sometimes, and 33.7 % place it regularly, but only without aspiration. Most responders prescribe bed rest for 24 (34.9 %) or 48 h (28.0 %), with much fewer prescribing bed rest for 72 h (6.3 %) and none more than 72 h, and 14.9 % of participants never prescribe bed rest. The vast majority of physicians (82.9 %, n = 145) always inform their patients after the operation in case of ID. CONCLUSIONS: There is substantial heterogeneity in the management of incidental durotomies. The majority of spine surgeons today aim at complete/sufficient primary repair of the ID with varying recommendations concerning postoperative bed rest. Still, there is a trend towards early mobilization if the incidental durotomy has been closed completely/sufficiently with no participant favoring bed rest for more than 72 h.

Early surgical education of residents is safe for microscopic lumbar disc surgery.

INTRODUCTION: It is a well-established dogma that many surgeons do not reach a quintessential level of their technical operative skills until successful completion of their training program. The aim of this study was to test the hypothesis that early introduction of supervised residents to non-complex spinal surgical procedures within a structured and supervised educational program does not harm the patient in terms of higher complication rates or worse pain- and health-related quality of life (HrQOL) outcomes. METHODS: A prospective study on 102 patients undergoing surgery for lumbar disc herniation (LDH) was performed. The procedures were dichotomized into two groups according to the surgeon's level of experience: teaching cases (neurosurgical residents in the 1st to 4th year of training) and non-teaching cases (experienced board-certified faculty neurosurgeons). Pain levels (VAS) and the HrQOL using the 12-item short-form health survey (SF-12) were measured at baseline, at 4 weeks and as a survey at 1 year postoperatively. In addition, data concerning the operation and the postoperative course including common complications were assessed. RESULTS: Intraoperative blood loss, length of surgery, as well as intra- and postoperative complications were similar between the study groups. Patients in both groups achieved equal results in terms of pain reduction after 4 weeks [mean VAS change -3.8 (teaching cases) vs. -3.1 (non-teaching cases), p = 0.25] and 1 year postoperatively [mean change in VAS -3.5 (teaching cases) vs. -3.37 (non-teaching cases), p = 0.84]. Teaching cases were 100 % (odds ratio of 1.00) as likely as non-teaching cases to achieve a favorable HrQOL response to surgery (p = 0.99). CONCLUSIONS: Early introduction of resident surgeons to lumbar microdiscectomy can be conducted safely within a structured and supervised educational program as it neither harms the patient nor leads to worse 1-year results. Surgical resident education may thus be implemented safely in times of rigorous working laws. However, a structured education program in which the senior surgeon gives advice, guidance and communicates cautions during each resident surgery is of paramount importance to provide high-quality patient care.

Non-assisted versus neuro-navigated and XperCT-guided external ventricular catheter placement: a comparative cadaver study.

BACKGROUND AND PURPOSE: Accurate placement of an external ventricular drain (EVD) for the treatment of hydrocephalus is of paramount importance for its functionality and in order to minimize morbidity and complications. The aim of this study was to compare two different drain insertion assistance tools with the traditional free-hand anatomical landmark method, and to measure efficacy, safety and precision. METHODS: Ten cadaver heads were prepared by opening large bone windows centered on Kocher's points on both sides. Nineteen physicians, divided in two groups (trainees and board certified neurosurgeons) performed EVD insertions. The target for the ventricular drain tip was the ipsilateral foramen of Monro. Each participant inserted the external ventricular catheter in three different ways: 1) free-hand by anatomical landmarks, 2) neuronavigation-assisted (NN), and 3) XperCT-guided (XCT). The number of ventricular hits and dangerous trajectories; time to proceed; radiation exposure of patients and physicians; distance of the catheter tip to target and size of deviations projected in the orthogonal plans were measured and compared. RESULTS: Insertion using XCT increased the probability of ventricular puncture from 69.2 to 90.2 % (p = 0.02). Non-assisted placements were significantly less precise (catheter tip to target distance 14.3 ± 7.4 mm versus 9.6 ± 7.2 mm, p = 0.0003). The insertion time to proceed increased from 3.04 ± 2.06 min. to 7.3 ± 3.6 min. (p < 0.001). The X-ray exposure for XCT was 32.23 mSv, but could be reduced to 13.9 mSv if patients were initially imaged in the hybrid-operating suite. No supplementary radiation exposure is needed for NN if patients are imaged according to a navigation protocol initially. CONCLUSION: This ex vivo study demonstrates a significantly improved accuracy and safety using either NN or XCT-assisted methods. Therefore, efforts should be undertaken to implement these new technologies into daily clinical practice. However, the accuracy versus urgency of an EVD placement has to be balanced, as the image-guided insertion technique will implicate a longer preparation time due to a specific image acquisition and trajectory planning.

Isolated cerebral metastasis of a triceps muscle leiomyosarcoma: a case report.

Leiomyosarcomas are rare malignant neoplasms. Intracranial metastases of this tumour are even less frequently observed and have mostly been described from uterine leiomyosarcomas. In this article, we describe the case of a single right frontal subcortical cerebral metastasis in a patient with a right triceps muscle leiomyosarcoma. A right-sided frontal craniotomy with macroscopically complete tumour removal was performed, followed by combined radio-chemotherapy. The patient died 10 months after the initial diagnosis of the intracranial metastasis due to systemic tumour progression, without any evidence of intracranial recurrence.

Incidence and relative survival of chordomas: the standardized mortality ratio and the impact of chordomas on a population.

BACKGROUND: Chordomas are rare bone tumors arising from remnants of the embryonic notochord. METHODS: Data for this study were obtained from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute (1973-2009) to calculate the incidence, relative survival (RS), and standardized mortality ratio (SMR) of patients diagnosed with intracranial and extracranial chordomas and to assess the effects of age and sex on this disease. RESULTS: The overall incidence of extracranial and intracranial chordomas was 8.4 per 10 million population. The median overall survival of patients with chordoma patients was 7.7 years. The median survival was 7.7 years for male patients and 7.8 years for female patients. Younger patients (aged <40 years) survived longer compared with older patients (10-year RS, 68% vs 43%). The estimated age-standardized 5-year, 10-year, and 20-year RS rates was 72%, 48%, and 31%, respectively. The SMR in the overall cohort was 4.6 (95% confidence interval, 4.22-5.0) or 21.0 (95% confidence interval, 16.6-27.2) in young adult patients and 3.0 (95% confidence interval, 2.6-3.4) in elderly patients. CONCLUSIONS: The elderly had a more aggressive form of this disease; and, other than the incidence, sex did not influence outcome in this disease. The study of chordomas presents a good case for the contribution that the SMR can have on measuring the impact of a disease on a population of patients. Although the younger population has better survival rates, the impact (SMR) in the younger age groups is much higher than in older populations.