Slow progress in the visibility of women in neurosurgery in the United States: opportunity for improvement.

OBJECTIVE: The goal of this study was to analyze the visibility of women within organized neurosurgery, including leadership positions, lectureships, and honored guest/award recipients at neurosurgical conferences. METHODS: A cross-sectional study was used to analyze the gender demographics within the five major national neurosurgical societies (Congress of Neurological Surgeons [CNS], American Association of Neurological Surgeons [AANS], Society of Neurological Surgeons [SNS], American Board of Neurological Surgery [ABNS], and Council of State Neurosurgical Societies [CSNS]) from 2000 to 2020. Data for top leadership positions, keynote speakers, honored guests, and invited lectureships at these neurosurgical societies were reviewed. Additionally, national neurosurgical residency match data from 2018 to 2020 were collected. For each aforementioned data point, gender was determined and confirmed via publicly available data. Data from the US News and World Report best hospitals publication for 2020 were applied for analyzing gender trends within neurosurgical residencies specifically. RESULTS: In the past 2 decades (2000-2020), top leadership positions across the neurosurgical organizations were held by 45 individuals, of whom 5 (11.1%) were women. Spanning from 2000 to 2018, just 8.1% (50 of 618) of guests/honored speakers on the national neurosurgical stage of the CNS, AANS, SNS, and CSNS meetings have been female. Excluding the Louise Eisenhardt Lecture (honoring women), the percentage of female guests/honored speakers at the AANS meeting was just 5% (17 of 367). For the CNS annual meetings, 13.4% (20 of 149) of the speakers were women from 2000 to 2018, whereas the CSNS annual meeting data from 2001 to 2018 found that 11.9% (7 of 59) of speakers were women. From 1952 to the present, there have been no female honored guests at the CNS annual meeting. Across the residency match cycles from 2018 to 2020, the percentages of matched applicants identifying as female have been 22.7%, 28.1%, and, most recently, 25.3%. The percentage of female residents is 28.5% (top 20 program) versus 24.3% (non-top 20 program) (p = 0.267). CONCLUSIONS: This study found that for all the data points surveyed, including leadership positions, invited lectureships at national neurosurgical meetings, and successful neurosurgical residency applicants, disproportionate female underrepresentation was evident. Consistent lack of visibility leads to a negative impact on progress in the recruitment and retention of women in neurosurgery. Visibility, mentorship, role models, and sponsorship are highly interrelated processes and are essential for meaningful progress.

Failures in Revascularization for Pediatric Moyamoya Disease and Syndrome: A Scoping Review.

BACKGROUND: Moyamoya disease (MMD) and moyamoya syndrome (MMS) are a rare cause of stroke commonly managed surgically. We conducted a scoping review to identify the current scope of the literature regarding factors associated with failure of revascularization surgery for MMD and MMS in pediatric patients and to catalyze future research. METHODS: A scoping review was conducted to explore failures of revascularization surgery for MMD and MMS in pediatric patients using the PubMed, Embase, and Scopus databases. Titles and abstracts returned from searches were screened for full-text review. Studies meeting inclusion criteria were reviewed in full, and relevant data were extracted. RESULTS: Of 2450 resultant articles, 15 were included. Angiographic outcomes were reported for 900 hemispheres, of which 442 (49.1%) were denoted as Matsushima grade A, 299 (33.2%) as Matsushima grade B, and 159 (17.7%) as Matsushima grade C. Patients with MMS had poorer angiographic outcomes than did patients with MMD. Patients with poor neovascularization had a greater degree of moyamoya vessels on follow-up angiogram. Suzuki stage was not associated with angiographic outcome in individual patients. Angiographic outcomes differed by surgical approach and were not associated with clinical outcomes. Literature identifying factors was sparse. CONCLUSIONS: The existing literature indicates that factors such as cause, degree of moyamoya vessels, and surgical approach may affect the likelihood of Matsushima grade C revascularization in pediatric patients with MMD and MMS. Future studies are necessary to definitively elucidate factors associated with failure of revascularization surgery for pediatric MMD.

Surgical versus conservative treatment of unilateral subaxial non-subluxed facet fractures: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Unilateral subaxial non-subluxed facet fractures (USNSFF) are a pathology seen in traumatic events such as motor vehicle accidents. Management involves either rigid collar bracing or surgical intervention. There currently is no consensus on the treatment of these injuries; this review aims to examine the extant data for recommendations as to which treatment is more effective. METHODS: MEDLINE, Scopus, and the Cochrane trial register were all searched on January 16, 2020, comparing outcomes for surgical and conservative therapy for USNSFF. The meta-analysis examined rates of treatment failure (need for subsequent operative management) in conservative versus surgical management. The meta-analysis was performed using a random effects model, with visualization in forest and L'Abbé plots. RESULTS: We identified six retrospective studies describing 270 patients, with three studies describing 137 patients used in the meta-analysis. Overall, a surgical success rate of 97.7 % and a non-operative success rate of 79.7 % was observed. A random effects model risk ratio of 1.66 (95 % CI: 0.61-4.52) was obtained, suggesting efficacy of surgical management over conservative management. CONCLUSION: The need for surgical intervention subsequent to initial management in the treatment of USNSFF was found to be lower in surgical treatment in contrast to conservative management. However, the studies that were included in the meta-analysis had patient cohorts with much higher rates of neurological deficit and ligamentous injury on presentation, indicating that these may be prognostic indicators of conservative management failure. Furthermore, those that did fail conservative management did not develop severely debilitating conditions. Accordingly, conservative treatment is generally sufficient as a first step in a majority of cases of USNSFF lacking neurological deficit or ligamentous involvement.

Suicide and traumatic spinal cord injury-a cohort study.

STUDY DESIGN: Retrospective and prospective observational. OBJECTIVE: The main objective of this study was to analyse suicide attempt as a cause of traumatic spinal cord injury (tSCI) and suicide as a cause of death after tSCI. SETTING: This study was conducted at two British spinal centres, Stoke Mandeville and Southport. METHODS: Long-term survival of patients who were newly admitted between 1991 and 2010, had survived the first post-injury year and had neurological deficit on discharge. Follow-up was discontinued on 31 December 2014. RESULTS: Among the 2304 newly admitted cases of tSCI, suicide attempt was the cause of injury in 63 cases (2.7%). By the end of 2014 there were 533 deaths of which 4.2% deaths were by suicide, with 91% of suicides happening in the first 10 years post injury. Multiple logistic regression analyses showed a higher mortality odds ratio (OR=4.32, P<0.001) and a much higher suicide OR (9.46, P<0.001) for persons injured in suicide attempts when compared with all other SCI aetiologies. The overall age-standardised suicide mortality rate was 62.5 per 100 000 persons per year (95% confidence interval=36.4-88.6), five times higher than the general population suicide rate for England and Wales in 2014 (12.2 per 100 000). CONCLUSIONS: Suicide attempt was the cause of tSCI in 2.7% of the sample and suicide was the cause of death in 4.2% of all deaths. The overall mortality and death by suicide were significantly higher in persons whose tSCI was caused by an attempted suicide when compared with the rest of the sample. Continued psychological attention following SCI, especially to those who were injured by suicide attempt, is warranted.

Causes of death after traumatic spinal cord injury-a 70-year British study.

DESIGN: Retrospective and prospective observational. OBJECTIVE: Analyse causes of death after traumatic spinal cord injury (tSCI) in persons surviving the first year post injury, and establish any trend over time. SETTING: Two spinal centres in Great Britain. METHODS: The sample consisted of 5483 patients with tSCI admitted to Stoke Mandeville and Southport spinal centres who were injured between 1943 and 2010, survived first year post injury, had residual neurological deficit on discharge and were British residents. Mortality information, including causes of death, was collected up to 31 December 2014. Age-standardised cause-specific mortality rates were calculated for selected causes of death, and included trends over time and comparison with the general population. RESULTS: In total, 2322 persons (42.3% of the sample) died, with 2170 (93.5%) having a reliable cause of death established. The most frequent causes of death were respiratory (29.3% of all certified causes), circulatory, including cardiovascular and cerebrovascular diseases (26.7%), neoplasms (13.9%), urogenital (11.5%), digestive (5.3%) and external causes, including suicides (4.5%). Compared to the general population, age-standardised cause-specific mortality rates were higher for all causes, especially skin, urogenital and respiratory; rates showed improvement over time for suicides, circulatory and urogenital causes, no significant change for neoplasms, and increase for skin and respiratory causes. CONCLUSIONS: Leading causes of death after tSCI in persons surviving the first year post injury were respiratory, circulatory, neoplasms and urogenital. Cause-specific mortality rates showed improvement over time for most causes, but were still higher than the general population rates, especially for skin, urinary and respiratory causes.

Long-term survival after traumatic spinal cord injury: a 70-year British study.

STUDY DESIGN: Retrospective and prospective observational. OBJECTIVES: Analyse long-term survival after traumatic spinal cord injury (SCI) in Great Britain over the 70-year study period, identify mortality risk factors and estimate current life expectancy. SETTING: Two spinal centres in Great Britain. METHODS: The sample consisted of patients with traumatic SCI injured 1943-2010 who survived the first year post-injury, had residual neurological deficit on discharge and were British residents. Life expectancy and trends over time were estimated by neurological grouping, age and gender, using logistic regression of person-years of follow-up combined with standard life table calculations. RESULTS: For the 5483 cases of traumatic SCI the mean age at injury was 35.1 years, 79.7% were male, 31.1% had tetraplegia AIS/Frankel ABC, 41.2% paraplegia ABC,and 27.7% functionally incomplete lesion (all Ds). On 31 December 2014, 54% were still alive, 42.3% had died and 3.7% were lost to follow-up. Estimated life expectancies improved significantly between the 1950s and 1980s, plateaued during the next two decades, before slightly improving again since 2010. The estimated current life expectancy, compared with the general British population, ranged from 18.1 to 88.4% depending on the ventilator dependency, level and completeness of injury, age and gender. CONCLUSIONS: Life expectancy after SCI improved significantly between the 1950s and 1980s, plateaued during the 1990s and 2000s, before slightly improving again since 2010, but still remains well below that of the general British population. SPONSORSHIP: Buckinghamshire Healthcare NHS Trust Charitable Spinal Fund and Ann Masson Legacy for Spinal Research Fund, UK.

Different effects of BCG strains - A natural experiment evaluating the impact of the Danish and the Russian BCG strains on morbidity and scar formation in Guinea-Bissau.

BACKGROUND: Different Bacillus Calmette-Guerin (BCG) vaccine strains may have different non-specific effects. We assessed the effect of two BCG strains (Danish and Russian) on childhood morbidity and BCG scarification in Guinea-Bissau. METHODS: During 2011-2013, infants in the Bandim Health Project's urban study area received the Danish or Russian BCG in a natural experiment. Health center consultations were registered at point of care and scar status and size at age 4½ months. We assessed the effect of strain on consultation rates between vaccination and age 45days in Cox proportional hazards models. Scar prevalence and size were compared using binomial regression and ranksum tests. RESULTS: Among 1206 children, 18% received Danish BCG (n=215) and 82% Russian BCG (n=991). The adjusted hazard ratio (aHR) for consultations was 0.94 (95% CI 0.60-1.46) for Danish BCG compared with Russian BCG. Girls vaccinated with Danish BCG tended to have lower consultation rates compared with girls vaccinated with Russian BCG (aHR 0.56 (0.25-1.24)), whereas the effect was opposite for boys (aHR 1.24 (0.74-2.11)), p=0.09. Children vaccinated with Danish BCG were more likely to develop a scar (97%) than children vaccinated with Russian BCG (87%), the relative risk (RR) being 1.11 (1.06-1.16). The effect was stronger in girls, and BCG scar size was larger among infants vaccinated with the Danish strain. CONCLUSION: BCG strain influences scar prevalence and scar size, and may have sex differential effects on morbidity. BCG strains are currently used interchangeably, but BCG scarring has been linked to subsequent survival. Hence, more research into the health effects of different BCG strains is warranted. Small adjustments of BCG production could potentially lower childhood morbidity and mortality at low cost.

Trauma-Related Critical Care.

BACKGROUND: Post-trauma resuscitation has evolved based on civilian and wartime experiences over the last decade. Similarly, data from large multicenter randomized trials have changed the management of critically ill trauma patients in the intensive care unit. METHODS: This is a review of the literature focusing on areas relevant to the management of trauma patients in the intensive care unit. RESULTS: The following topics are included: (1) ventilator management, (2) trauma sepsis, (3) use of vasopressors in hemorrhage, (4) glucose control, (5) nutrition, and (6) hemodynamic monitoring. CONCLUSION: This review demonstrated the most recent data of trauma-related critical care. Further studies will be needed to settle growing controversies in the management of critically injured patients.

The Sir Ludwig Guttmann lecture 2012: the contribution of Stoke Mandeville Hospital to spinal cord injuries.

This Ludwig Guttmann Lecture was presented at the 2012 meeting of the International Spinal Cord Society in London. It describes the contribution of Stoke Mandeville Hospital to the field of spinal cord injuries. Dr Ludwig Guttmann started the Spinal Unit at Stoke Mandeville Hospital in 1944 and introduced a novel, comprehensive method of care, which included early admission, prevention and treatment of spinal cord injury related complications, active rehabilitation and social reintegration. Soon a dedicated specialist team was assembled and training of visitors was encouraged, some of whom went on to start their own spinal units. Research went hand in hand with clinical work, and over the years more than 500 scientific contributions from Stoke Mandeville have been published in peer reviewed journals and books. Guttmann introduced sport as a means of physical therapy, which soon lead to organised Stoke Mandeville Games, first national in 1948, then international in 1952 and finally the Paralympic Games in 1960. Stoke Mandeville is regarded as the birthplace of the Paralympic movement, and Guttmann was knighted in 1966. Stoke Mandeville is also the birthplace of the International Medical Society of Paraplegia, later International Spinal Cord Society, which was formed during the International Stoke Mandeville Games in 1961, and of the Society's medical journal Paraplegia, later Spinal Cord, first published in 1963. Guttmann's followers have continued his philosophy and, with some new developments and advances, the present day National Spinal Injuries Centre at Stoke Mandeville Hospital provides comprehensive, multidisciplinary acute care, rehabilitation and life-long follow-up for patient with spinal cord injuries of all ages.

Sensitivity to change of the cutaneous electrical perceptual threshold test in longitudinal monitoring of spinal cord injury.

STUDY DESIGN: Prospective longitudinal experimental study. OBJECTIVES: The aim of this study was to assess the sensitivity to change of the electrical perceptual threshold (EPT) test during the longitudinal monitoring of neurological changes in patients with incomplete spinal cord injury (SCI). SETTING: National Spinal Injuries Centre, Stoke Mandeville Hospital, Buckinghamshire Hospitals NHS Trust, Buckinghamshire, UK. METHODS: Perceptual threshold to 3 Hz cutaneous electrical stimulation was measured in 11 patients with incomplete SCI at selected American Spinal Injuries Association (ASIA) sensory key points on four occasions. The first three measurements were performed within a 5-day period (baseline) and the fourth measurement (follow-up) at least 9 months later. The results were tested for statistical significance and the effect sizes were calculated. RESULTS: There were no significant differences between the EPT results of the three baseline assessments. When the mean baseline and follow-up EPT results were compared, there were no significant differences in EPT values above the sensory level of lesion, but a significant difference (reduction in threshold values) was found at and below the level of SCI, with medium and large effect sizes, respectively. CONCLUSION: The EPT test showed good sensitivity to change in dermatomes at and directly below the sensory level of the SCI. This makes it a potentially useful quantitative sensory instrument for detecting changes in sensory function during longitudinal monitoring of patients with SCI.

Ethical considerations in the collection of genetic data from critically ill patients: what do published studies reveal about potential directions for empirical ethics research?

Critical illness trials involving genetic data collection are increasingly commonplace and pose challenges not encountered in less acute settings, related in part to the precipitous, severe and incapacitating nature of the diseases involved. We performed a systematic literature review to understand the nature of such studies conducted to date, and to consider, from an ethical perspective, potential barriers to future investigations. We identified 79 trials enrolling 24 499 subjects. Median (interquartile range) number of participants per study was 263 (116.75-430.75). Of these individuals, 16 269 (66.4%) were Caucasian, 1327 (5.4%) were African American, 1707 (7.0%) were Asian Pacific Islanders and 139 (0.6%) were Latino. For 5020 participants (20.5%), ethnicity was not reported. Forty-eight studies (60.8%) recruited subjects from single centers and all studies examined a relatively small number of genetic markers. Technological advances have rendered it feasible to conduct clinical studies using high-density genome-wide scanning. It will be necessary for future critical illness trials using these approaches to be of greater scope and complexity than those so far reported. Empirical research into issues related to greater ethnic inclusivity, accuracy of substituted judgment and specimen stewardship may be essential for enabling the conduct of such trials.

Inter-rater reliability of motor and sensory examinations performed according to American Spinal Injury Association standards.

STUDY DESIGN: Prospective observational. AIM: To examine inter-rater reliability of motor and sensory examinations performed according to American Spinal Injury Association (ASIA) standards. SETTING: National Spinal Injuries Centre, Stoke Mandeville Hospital, Buckinghamshire Hospitals NHS Trust, UK. MATERIAL AND METHOD: Results of ASIA motor and sensory examinations performed by two experienced examiners on 45 patients with spinal cord injury (SCI) were compared. RESULTS: Total ASIA scores showed very strong correlation between the two examiners, with Pearson correlation coefficients and intraclass correlation coefficients exceeding 0.96, P<0.01 for total motor, light touch and pin prick scores. The agreement for individual muscle testing of the 10 ASIA key muscles showed substantial agreement for majority of muscles, with the weighted Kappa coefficient range 0.649-0.993, P<0.05. The overall agreement in assignment of manual muscle testing grades (0-5) was 82% on the right and 84% on the left, with the strongest agreement for grade '0' and the weakest for grade '3'. The unweighted Kappa coefficient for agreement in motor and sensory levels ranged from 0.68 to 0.78 (P<0.01). There was no difference in ASIA impairment grades derived from the two examiners' results. CONCLUSIONS: Our study results showed very good levels of agreement in ASIA clinical examinations between two experienced examiners. The established degree of variability due to inter-rater differences should be taken into account in study design of clinical trials with more than one assessor..

Perceptual threshold to cutaneous electrical stimulation in patients with spinal cord injury.

STUDY DESIGN: Prospective experimental. OBJECTIVES: The aim of this study was to develop a quantitative sensory test (QST) that could be used for assessing the level and the density (degree of impairment) of spinal cord injury (SCI) and for monitoring neurological changes in patients with SCI. SETTING: National Spinal Injuries Centre, Stoke Mandeville Hospital, Buckinghamshire Hospitals NHS Trust, UK. METHODS: Perceptual threshold to 3 Hz cutaneous electrical stimulation was measured in 30 control subjects and in 45 patients with SCI at American Spinal Injuries Association (ASIA) sensory key points for selected dermatomes between C3 and S2 bilaterally. Electrical perceptual threshold (EPT) was recorded as the lowest ascending stimulus intensity out of three tests at which the subject reported sensation. The level of SCI according to EPT results was established for right and left sides as the most caudal spinal segment at which patient's EPT was within the control range (mean +/- 2 standard deviation (SD)). The level of SCI, according to EPT, was then compared with clinical sensory level derived according to ASIA classification. RESULTS: In the control group, EPT depended on the dermatome tested and was lowest for T1 (1.01 +/- 0.23 mA, mean +/- SD) and highest for L5 (3.32 +/- 1.14 mA). There was strong correlation between corresponding right and left dermatomes and between repeated assessments. In the SCI group, the level of lesion according to EPT and clinical testing was the same in 43 of the 90 tests (48%). In 37 cases (41%), the EPT level was higher than the clinical level, and in 10 cases (11%), it was lower. Below the level of lesion in incomplete SCI and in the zone of partial preservation in complete SCI, the EPT values in most dermatomes were raised compared with the control group. CONCLUSIONS: EPT is a simple, reproducible QST that can assess both the level and the density of SCI. It seems to add sensitivity and resolution to the standard clinical testing and could be a useful adjunct in longitudinal monitoring of patients with SCI for research purposes during natural recovery and therapeutic interventions. SPONSORSHIP: International Spinal Research Trust (ISRT), UK, Grant CLI001.

Magnetic brain stimulation can improve clinical outcome in incomplete spinal cord injured patients.

STUDY DESIGN: Preliminary longitudinal clinical trial. OBJECTIVES: To test the efficacy of repetitive transcranial magnetic stimulation (rTMS) in modulating corticospinal inhibition and improving recovery in stable incomplete spinal cord injury (iSCI). SETTING: National Spinal Injuries Centre, Stoke Mandeville Hospital, Bucks, UK and Division of Neuroscience, Imperial College Faculty of Medicine, Charing Cross Hospital, London, UK. METHODS: Four stable iSCI patients were treated with rTMS over the occipital cortex (sham treatment) and then over the motor cortex (real treatment). Patients were assessed using electrophysiological, clinical and functional measures before treatment, during sham treatment, during the therapeutic treatment and during a 3-week follow-up period. RESULTS: Cortical inhibition was reduced during the treatment week. Perceptual threshold to electrical stimulation of the skin, ASIA clinical measures of motor and sensory function and time to complete a peg-board improved and remained improved into the follow-up period. CONCLUSION: In this preliminary trial, rTMS has been shown to alter cortical inhibition in iSCI and improve the clinical and functional outcome. SPONSORSHIP: This work was supported by the International Spinal Research Trust.

Towards improved clinical and physiological assessments of recovery in spinal cord injury: a clinical initiative.

Clinical practice and scientific research may soon lead to treatments designed to repair spinal cord injury. Repair is likely to be partial in the first trials, extending only one or two segments below the original injury. Furthermore, treatments that are becoming available are likely to be applied to the thoracic spinal cord to minimise loss of function resulting from damage to surviving connections. These provisos have prompted research into the improvement of clinical and physiological tests designed (1) to determine the level and density of a spinal cord injury, (2) to provide reliable monitoring of recovery over one or two spinal cord segments, and (3) to provide indices of function provided by thoracic spinal root innervation, presently largely ignored in assessment of spinal cord injury. This article reviews progress of the Clinical Initiative, sponsored by the International Spinal Research Trust, to advance the clinical and physiological tests of sensory, motor and autonomic function needed to achieve these aims.

Charcot joint of the spine, a cause of autonomic dysreflexia in spinal cord injured patients.

STUDY DESIGN: Case report of two subjects. OBJECTIVE: Charcot joints of the spine as a cause of Autonomic Dysreflexia in spinal cord lesions. SETTING: Stoke Mandeville Hospital, UK. METHOD: Two patients with long standing spinal cord lesions developed symptoms of headaches and sweating associated with sitting up and transfers. In both cases no other cause was found to account for Autonomic Dysreflexia. RESULT: Charcot Joints of the spine below the level of injury were demonstrated in both cases and symptoms resolved with prolonged bed rest. CONCLUSION: As care of spinally injured patients continues to improve, they live longer and lead a more active lifestyle, it is expected that the incidence and prevalence of Charcot's joints will increase. Therefore the knowledge and heightened awareness of this entity, early diagnosis and detection with plain X-rays for urinary surveillance, may reduce the morbidity in spinal cord injured patients.

Decreased cutaneous sensory axon-reflex vasodilatation below the lesion in patients with complete spinal cord injury.

The histamine-induced skin flare response has been considered of practical value in determining the level of a spinal cord lesion, but clinical observations have varied widely with regard to the nature and degree of change below the lesion. We have quantified cutaneous sensory axon-reflex vasodilatation in patients with complete spinal cord injury (SCI) above and below the lesion, and compared the findings with normal subjects. Axon-reflex vasodilatation was induced by intradermal histamine injection, and measured by (a) laser Doppler fluxmetry and (b) tracing the surface area of the flare. Axon-reflex vasodilatation was present in all SCI patients above and below the lesion, but was significantly diminished below the lesion by both measures (pflux rise = 0.0008; pflare = 0.023), and in comparison with controls (by 39%). The flux increase was significantly correlated with the area of flare (r = 0.82; p = 0.02). Axon-reflex vasodilatation and visual analogue scale (VAS) pain scores on histamine injection were not significantly different above the lesion in SCI patients from controls. Baseline laser Doppler flux was not different at any test site in SCI and normal subjects. The cutaneous sensory axon-reflex is thus significantly diminished in SCI patients below the level of the lesion, but the underlying mechanism is unclear. A possible explanation under investigation is that increased basal or reflex sympathetic vasoconstriction mediated via the isolated spinal cord may counteract the vasodilatation produced by the cutaneous sensory terminals.

Organisation of the sympathetic skin response in spinal cord injury.

OBJECTIVES: The sympathetic skin response (SSR) is a technique to assess the sympathetic cholinergic pathways, and it can be used to study the central sympathetic pathways in spinal cord injury (SCI). This study investigated the capacity of the isolated spinal cord to generate an SSR, and determined the relation between SSR, levels of spinal cord lesion, and supraspinal connections. METHODS: Palmar and plantar SSR to peripheral nerve electrical stimulation (median or supraorbital nerve above the lesion, and peroneal nerve below the lesion) were recorded in 29 patients with SCI at various neurological levels and in 10 healthy control subjects. RESULTS: In complete SCI at any neurological level, SSR was absent below the lesion. Palmar SSR to median nerve stimuli was absent in complete SCI with level of lesion above T6. Plantar SSR was absent in all patients with complete SCI at the cervical and thoracic level. In incomplete SCI, the occurrence of SSR was dependent on the preservation of supraspinal connections. For all stimulated nerves, there was no difference between recording from ipsilateral and contralateral limbs. CONCLUSIONS: No evidence was found to support the hypothesis that the spinal cord isolated from the brain stem could generate an SSR. The results indicate that supraspinal connections are necessary for the SSR, together with integrity of central sympathetic pathways of the upper thoracic segments for palmar SSR, and possibly all thoracic segments for plantar SSR.