Electrophysiologic Findings in Post-Traumatic Syringomyelia: Implications for Clinical Management

ABSTRACT

Traumatic spinal cord injured (SCI) patients may develop pain, new weakness and/or sensory loss due to an enlarging fluid-filled cyst in the spinal cord. The clinical history and physical exam are nonspecific and insensitive, particularly for diagnosing and monitoring recurrent or progressive post-traumatic syringomyelia (PTS). We compare the sensitivity and specificity of three electrodiagnostic tests, median and ulnar F waves, electromagnetic motor evoked potentials (MEP), and needle electromyography, with respect to syrinx by imaging (MRI or CT scan) and neurologic progression on serial clinical exams. Central motor conduction time (CMCT) calculated from scalp and spine MEP was the most sensitive diagnostic test. F waves were less sensitive and less specific than the CMCT, and did not provide evidence of syrinxes in the mid or upper cervical cord. Positive sharp wave and fibrillation potentials were the least sensitive and least specific. The CMCT is a useful adjunct to imaging studies for diagnosing and monitoring PTS.     

Fertility of Spinal Cord Injured Males: Effect of Genitourinary Infection and Bladder Management on Results of Electroejaculation

ABSTRACT

Thirty-eight men undergoing electroejaculation (EEJ) procedures for anejaculatory infertility were examined for the presence or absence of infection in urine and semen. In 29 spinal cord injury patients, a high incidence of infected urine and infected semen (41% and 56%, respectively) was seen, in contrast to patients with normal bladder function (0% and 11 %).

Urinary infection was associated with slightly lower sperm quality and lower pregnancy rates (10% vs 30% in the presence of sterile urine). Semen infection had no effect on sperm counts or pregnancy rates. If intermittent self-catheterization (ISC) was used to empty the neurogenic bladder, slightly better sperm quality was seen, the total failure rate was less, and much better pregnancy rates (44%) resulted than for patients using an alternative bladder management (7%).

Antibiotics did not reduce the incidence of urine or semen infection, but did improve sperm counts slightly. Continuous prophylaxis was associated with bacterial resistance to many oral antibiotics and had no advantage over a short course of antibiotics prior to the procedure.

Despite the above associations, the sperm quality in our patient population was never normal compared with that of men who ejaculate normally. We conclude that the low sperm quality seen in electroejaculation specimens from spinal cord injured males is not due entirely to infection or to the type of bladder management. Short courses of antibiotics, instead of continuous antibiotic prophylaxis, may be beneficial. Intermittent catheterization is superior to other methods of neurogenic bladder management in maintaining the fertility of spinal cord injured men.     

Altered resting hemodynamics in lower-extremity arteries of individuals with spinal cord injury

Abstract

Objective

To investigate lower-extremity arterial hemodynamics in individuals with spinal cord injury (SCI). We hypothesized that oscillatory shear index would be altered and resting mean shear would be higher in the lower-extremity arteries of SCI.

Research

Cross-sectional study of men and women with SCIs compared to able-bodied controls.

Subjects

Subjects included 105 ages 18–72 years with American Spinal Injury Association (ASIA) Impairment Scale grades A, B, or C and injury duration at least 5 years. Subjects were matched for age and cardiovascular disease risk factors with 156 able-bodied controls.

Methods

Diameter and blood velocity were determined with subject at rest via ultrasound in superficial femoral, popliteal, brachial, and carotid arteries. Mean shear, antegrade shear, retrograde shear, and oscillatory shear index were calculated.

Results

Oscillatory shear index was lower in SCI compared to controls for superficial femoral (0.16 ± 0.10 vs. 0.26 ± 0.06, P < 0.01) and popliteal arteries (0.20 ± 0.11 vs. 0.26 ± 0.05, P < 0.01). Mean shear rate was higher in SCI compared to controls for superficial femoral (43.54 ± 28.0 vs. 20.48 ± 13.1/second, P < 0.01) and popliteal arteries (30.43 ± 28.1 vs. 11.68 ± 9.5/second, P < 0.01).

Conclusions

The altered resting hemodynamics in SCI are consistent with an atheroprotective hemodynamic environment.     

Auditory P3 Event Related Potentials (ERP) and Brainstem Auditory Evoked Responses (BAER) after Spinal Cord Injury in Humans

Abstract

Previous studies have observed altered somatotopic sensory fields after experimental deafferentation in animals as well as enhanced somatosensory evoked potentials and altered cortical motor pathways following spinal cord injury (SCI) in humans. These observations indicate that cortical reorganization may occur subsequent to SCI. In earlier work, we have observed attenuated amplitudes for both tactile P3 and auditory N1/P2 orienting event-related potentials (ERP) in spinal cord injured groups. These results suggest that the reorganization process may have functional perceptual and cognitive consequences. In an effort to determine if deafferentation affects the P3 ERP using stimuli other than somatosensory, we measured brain activity from central recording sites during an auditory “oddball” task. Additionally, we obtained brainstem auditory evoked responses (BAER) in order to assess subcortical primary auditory pathways as well. Results show that the SCI groups produced significantly attenuated N1/P2 complexes and P3 when compared to controls. Also, the quadriplegic group exhibited increased latencies of the P3 at frontal and central sites. There were no differences between groups in BAER results. These findings suggest that primary subcortical auditory information processing stages remain intact after SCI although later stages may be significantly altered. (J Spinal Cord Meet, 18:208–215)     

Diagnostic Pitfalls: Case Report Of Scurvy In A Man With Spinal Cord Injury

Abstract

Background: A 49-year-old man with spinal cord injury (SCI) developed a progressive purpuric rash and painful swelling of the lower extremities, in addition to chronic purpura over the ischial tuberosities.

Design: Case report

Findings: Following an extensive workup for presumed vasculitis, a skin biopsy showed evidence of scurvy. Risk facto rs for scurvy included limited means of transportation, living alone, and alcohol abuse.

Conclusions: Scurvy can be confused with disorders common among SCI patients, such as vasculitis, venous thrombosis, occult trauma, and pressure injury. Scurvy should be considered in the differential diagnosis of skin lesions, especially in individuals who abuse alcohol and live alone.     

Spinal Cord Injuries in Children and Adolescents: A Review

Abstract

This introductory review provides an overview of pediatric-onset spinal cord injury, emphasizing unique clinical and epidemiologic features, pathophysiology, medical and musculoskeletal complications, and psychosocial and management issues. Developmental factors influence the approach to bowel and bladder programs, mobility, patient education, and management of complications. Rehabilitation goals must be set for each developmental stage, with the final goal being that of a satisfying and productive adult life.     

Reliability Of Arm Wingate Anaerobic Testing In Persons With Complete Paraplegia

Abstract

Background: Accurate, reliable assessment of upper extremity muscular power in persons with paraplegia caused by spinal cord injury (SCI) would provide an objective indication of their ability to generate the forces necessary for the performance of daily activities. Wingate Anaerobic Testing (WAnT) consists of a 30-second sprint test on a cycle ergometer and has been used widely in both athletic and research settings.

Purpose: To examine test-retest reliability of arm WAnT performance in persons with complete SCI and paraplegia.

Methods: Forty-three participants with thoracic-level paraplegia (T2 through T12) performed 2 trials of arm WAnT with 2 to 7 days between each trial. Testing was performed using a Monarch 834E ergometer with participants seated in their wheelchairs. Participants were directed to crank at maximal pace for 30 seconds against a resistance load equivalent to 3.5% of their body mass. The SMI OptoSensor 2000 system was used to determine values of peak power (P_peak), mean power (P_mean), minimum power, and rate of fatigue, which were compared between trials using 1-way analysis of variance for repeated measures. Coeffi cients of determination (r₂) were calculated between trials for P_peak and P_mean.

Results: No significant diffe rence was found between trials for any of the power output variables. Regression analysis ind icat ed that P_peak and P_mean were closely associated between the 2 trials (r₂= 0.92 and 0.94, respectively).

Conclusion: Arm WAnT is a reliable measurement tool for the assessment of upper extremity muscular power in persons with complete paraplegia.     

Low-Frequency Fatigue in Individuals With Spinal Cord Injury

Abstract

Background/Objective: This study examined magnitude and recovery of low-frequency fatigue (LFF) in the quadriceps after electrically stimulated contractions in spinal cord-injured (SCI) and able-bodied subjects.

Subjects: Nine SCI (ASIA A-C, levels C5-T9, injured 13.6 ± 12.2 years) and 9 sedentary able-bodied subjects completed this study.

Methods: Fatigue was evoked in 1 thigh, and the nonfatigued leg served as a control. The fatigue test for able-bodied subjects lasted 15 minutes. For SCI, stimulation was adjusted so that the relative drop in force was matched to the able-bodied group. Force was assessed at 20 (P20) and 100 Hz (PI 00), and the ratio of P20/P100 was used to evaluate LFF in thighs immediately after, at 10, 20, and 60 minutes, and at 2, 4, 6, and 24 hours after a fatigue test.

Results: The magnitude of LFF (up to 1 hour after fatigue) was not different between able-bodied and patients with SCI. However, recovery of LFF over 24 hours was greater in able-bodied compared with patients with SCI in both the experimental (P < 0.001) and control legs (P < 0.001). The able-bodied group showed a gradual recovery of LFF over time in the experimental leg, whereas the SCI group did not.

Conclusions: These results show that individuals with SCI are more susceptible to LFF than able-bodied subjects. In SCI, simply assessing LFF produced considerable LFF and accounted for a substantial portion of the response. We propose that muscle injury is causing the dramatic LFF in SCI, and future studies are needed to test whether “fatigue” in SCI is actually confounded by the effects of muscle injury.     

Acute Outcomes of Cervical Spine Injuries in the Elderly: Atlantaxial vs Subaxial Injuries

Abstract

Background/Objective: Recent studies have reported on the outcomes of spinal cord injuries in the elderly. Our aim was to identify acute survival differences between elderly patients with atlantoaxial injuries relative to subaxial injuries at our institution and to determine whether operative treatment is associated with improved survival rates in either population.

Study Design: Retrospective database review of all traumatic cervical spine injuries in patients at least 65 years of age at a single tertiary care center.

Methods: A total of 193 consecutive patients at least 65 years of age treated at a single tertiary care center over a 12-year period were identified. Initial hospitalization records were reviewed. Patients were divided by anatomic level of injury: atlantoaxial (C1 or C2) and subaxial (C3 or below). Demographics, mechanism, and mortality rates were compared. Each group was further divided by treatment (operative or nonoperative), and inpatient survival rates were compared.

Results: Statistically similar survival rates were observed among patients with atlantoaxial and subaxial injuries (P= 0.10). Patients with nonoperatively treated subaxial injuries died at significantly higher rates than did their operatively treated peers (P < 0.05).

Conclusions: In this large comprehensive series of elderly patients with cervical spine injuries, survival rates were comparable regardless of anatomic level of injury. The operative treatment of subaxial injuries was associated with an improved acute survival rate vs nonoperative management. Further prospective study is needed to better assess this relationship.     

Reliability and validity of the capabilities of upper extremity test (CUE-T) in subjects with chronic spinal cord injury

Abstract

Objective

To determine the reliability and validity of the capabilities of upper extremity test (CUE-T), a measure of functional limitations, in patients with chronic tetraplegia.

Design

Repeated measures.

Setting

Outpatient rehabilitation center.

Participants

Fifty subjects (36 male/14 female) with spinal cord injury (SCI) of ≥1-year duration participated. Subjects were 17–81 years old (mean 48.1 ± 18.2); neurological levels ranged from C2 through T6, American Spinal Injury Association Impairment Scale grades A–D.

Interventions

Not applicable.

Outcome measures

Intraclass correlation coefficients (ICC), weighted kappa and repeatability values for CUE-T; Spearman correlations of CUE-T with upper extremity motor scores (UEMS), and self-care and mobility portions of the Spinal Cord Independence Measure, vIII (SCIM III).

Results

Score ranges for UEMS were 8–50, CUE-T 7–135, self-care SCIM 0–20, and mobility SCIM 0–40. The ICC values for total, right, and left side scores were excellent (0.97–0.98; 95% confidence interval 0.96–0.99). Item weighted kappa values were ≥0.60 for all but five items, four of which were right and left pronation and supination. Repeatability of total score was 10.8 points, right and left sides 6.3 and 6.1 points. Spearman correlations of the total CUE-T with the UEMS and SCIM self-care and mobility scores were 0.83, 0.70, and 0.55 respectively.

Conclusions

The CUE-T displays excellent test–retest reliability, and good–excellent correlation with impairment and capacity measures in persons with chronic SCI. After revising pronation and supination test procedures, the sensitivity to change should be determined.