Transmission of low-intensity vibration through the axial skeleton of persons with spinal cord injury as a potential intervention for preservation of bone quantity and quality

Abstract

Background/objective: Persons with spinal cord injury (SCI) develop marked bone loss from paralysis and immobilization. Low-intensity vibration (LIV) has shown to be associated with improvement in bone mineral density in post-menopausal women and children with cerebral palsy. We investigated the transmissibility of LIV through the axial skeleton of persons with SCI as an initial approach to determine whether LIV may be used as a clinical modality to preserve skeletal integrity.

Methods: Transmission of a plantar-based LIV signal (0.27 ± 0.11 g; 34 Hz) from the feet through the axial skeleton was evaluated as a function of tilt-table angle (15, 30, and 45°) in seven non-ambulatory subjects with SCI and ten able-bodied controls. Three SCI and five control subjects were also tested at 0.44 ± 0.18 g and 34 Hz. Transmission was measured using accelerometers affixed to a bite-bar to determine the percentage of LIV signal transmitted through the body.

Results: The SCI group transmitted 25, 34, and 43% of the LIV signal, and the control group transmitted 28, 45, and 57% to the cranium at tilt angles of 15, 30, and 45°, respectively. No significant differences were noted between groups at any of the three angles of tilt.

Conclusion: SCI and control groups demonstrated equivalent transmission of LIV, with greater signal transmission observed at steeper angles of tilt. This work supports the possibility of the utility of LIV as a means to deliver mechanical signals in a form of therapeutic intervention to prevent/reverse skeletal fragility in the SCI population.     

Transmission of low-intensity vibration through the axial skeleton of persons with spinal cord injury as a potential intervention for preservation of bone quantity and quality

Background/objective

Persons with spinal cord injury (SCI) develop marked bone loss from paralysis and immobilization. Low-intensity vibration (LIV) has shown to be associated with improvement in bone mineral density in post-menopausal women and children with cerebral palsy. We investigated the transmissibility of LIV through the axial skeleton of persons with SCI as an initial approach to determine whether LIV may be used as a clinical modality to preserve skeletal integrity.

Methods

Transmission of a plantar-based LIV signal (0.27 ± 0.11 g; 34 Hz) from the feet through the axial skeleton was evaluated as a function of tilt-table angle (15, 30, and 45°) in seven non-ambulatory subjects with SCI and ten able-bodied controls. Three SCI and five control subjects were also tested at 0.44 ± 0.18 g and 34 Hz. Transmission was measured using accelerometers affixed to a bite-bar to determine the percentage of LIV signal transmitted through the body.

Results

The SCI group transmitted 25, 34, and 43% of the LIV signal, and the control group transmitted 28, 45, and 57% to the cranium at tilt angles of 15, 30, and 45°, respectively. No significant differences were noted between groups at any of the three angles of tilt.

Conclusion

SCI and control groups demonstrated equivalent transmission of LIV, with greater signal transmission observed at steeper angles of tilt. This work supports the possibility of the utility of LIV as a means to deliver mechanical signals in a form of therapeutic intervention to prevent/reverse skeletal fragility in the SCI population.     

Hypothermia in patients with chronic spinal cord injury

DESIGN: Retrospective analysis of medical records. BACKGROUND/OBJECTIVES: To determine frequency and degree of hypothermic episodes in patients with chronic spinal cord injury (SCI). SETTING: Veterans Administration Medical Center. METHODS: Research involved analysis of body temperature records of 50 chronic patients with tetraplegia. All patients were men with a length of injury of 19 +/- 6 years. Mean age was 53 +/- 15 (SD) years. Data were derived from the computerized patient record database system of the Veterans Administration Medical Center. Results were classified into 3 groups: (a) hypothermia (< 95 degrees F), (b) subnormal temperature (< 97.7 degrees F), and normal temperatures (97.7 degrees F to 98.4 degrees F). Body temperature was recorded during hospitalization (minimum duration of 30 days) using an oral probe twice a day. Ambient temperature was controlled by a central air-conditioning system and maintained at 72 degrees F to 74 degrees F. RESULTS: A total of 867 measurements of body temperature were evaluated; normal temperature was recorded 298 times (35%), subnormal temperature was recorded 544 times (63%), and hypothermia was recorded 25 times (3%). There were 15 patients with 30 hypothermic episodes; subnormal temperature was found in all 50 patients from 1 to 47 times. Regression analysis of age and duration of SCI showed a nonsignificant relationship with body temperature. CONCLUSIONS: Our data suggest that patients with tetraplegia after SCI have significant dysfunction of thermoregulation associated with frequent episodes of subnormal body temperature in a normal ambient environment. Further studies are needed to evaluate possible consequences of low temperatures on the general health of patients and to develop preventive interventions.     

Deep venous thrombosis in patients with chronic spinal cord injury

Context/Objective: Deep venous thrombosis (DVT) is a well-known complication of an acute spinal cord injury (SCI). However, the prevalence of DVT in patients with chronic SCI has only been reported in a limited number of studies. The aim of our study was to examine the prevalence of DVT in patients with SCI beyond three months after injury.

Design: Cross-sectional study.

Setting: Rehabilitation Department at the Bydgoszcz University Hospital in Poland.

Participants: Sixty-three patients with SCI that were more than 3 months post injury. The patients, ranging in age from 13 to 65 years, consisted of 15 women and 48 men; the mean age of the patients was 32.1 years. The time from injury varied from 4 to 124 months.

Outcome measures: Clinical assessment, D-dimer and venous duplex scan.

Results: The venous duplex scan revealed DVT in 5 of the 63 patients. The post-injury time in four of the patients varied between 4 and 5 months; one patient was 42 months post-injury.

Conclusion: DVT occurred in patients with chronic SCI, mainly by the 6th post injury month.     

Modification of spasticity by transcutaneous spinal cord stimulation in individuals with incomplete spinal cord injury

Context/objective

To examine the effects of transcutaneous spinal cord stimulation (tSCS) on lower-limb spasticity.

Design

Interventional pilot study to produce preliminary data.

Setting

Department of Physical Medicine and Rehabilitation, Wilhelminenspital, Vienna, Austria.

Participants

Three subjects with chronic motor-incomplete spinal cord injury (SCI) who could walk ≥10 m.

Interventions

Two interconnected stimulating skin electrodes (Ø 5 cm) were placed paraspinally at the T11/T12 vertebral levels, and two rectangular electrodes (8 × 13 cm) on the abdomen for the reference. Biphasic 2 ms-width pulses were delivered at 50 Hz for 30 minutes at intensities producing paraesthesias but no motor responses in the lower limbs.

Outcome measures

The Wartenberg pendulum test and neurological recordings of surface-electromyography (EMG) were used to assess effects on exaggerated reflex excitability. Non-functional co-activation during volitional movement was evaluated. The timed 10-m walk test provided measures of clinical function.

Results

The index of spasticity derived from the pendulum test changed from 0.8 ± 0.4 pre- to 0.9 ± 0.3 post-stimulation, with an improvement in the subject with the lowest pre-stimulation index. Exaggerated reflex responsiveness was decreased after tSCS across all subjects, with the most profound effect on passive lower-limb movement (pre- to post-tSCS EMG ratio: 0.2 ± 0.1), as was non-functional co-activation during voluntary movement. Gait speed values increased in two subjects by 39%.

Conclusion

These preliminary results suggest that tSCS, similar to epidurally delivered stimulation, may be used for spasticity control, without negatively impacting residual motor control in incomplete SCI. Further study in a larger population is warranted.     

Age-related prevalence of low testosterone in men with spinal cord injury

Objective

To describe the relationship of advancing age in persons with chronic spinal cord injury (SCI) on the prevalence of low testosterone in men with SCI compared to historical normative data from able-bodied men in the general population.

Design

Retrospective, cross-sectional study. Two hundred forty-three healthy, non-ambulatory outpatient men with chronic SCI from age of 21 to 78 years were included in this retrospective analysis.

Results

Forty-six percent of men with SCI were identified as having low serum total testosterone concentrations (total testosterone <11.3 nmol/l). The age-related decline in SCI for total serum testosterone concentration was 0.6%/year compared to 0.4%/year in the Massachusetts Male Aging Study. Between the third and eighth decade of life, men with SCI had a 15, 39, 50, 53, 58, and 57% prevalence rate of low serum total testosterone, which is higher than values reported for each decade of life for able-bodied men in the Baltimore Longitudinal Study on Aging.

Conclusion

Compared with the general population, low serum total testosterone concentration occurs earlier in life in men with SCI, at a higher prevalence by decade of life, and their age-related decline in circulating total testosterone concentration is greater. Studies of T replacement therapy in men with SCI should assist in determining the possible functional and clinical benefits from reversing low serum total testosterone concentration.     

Breaking the news in spinal cord injury

Breaking the bad news in terms of prognosis for significant motor recovery following a neurologically complete spinal cord injury (SCI) is one of the most difficult tasks for the spinal cord medicine specialist. Learning the skills to facilitate this communication is extremely important to better assist patients to understand their prognosis as well as foster hope for their future. If bad news is delivered poorly it can cause confusion and long-lasting distress and resentment; if done well, it may assist understanding, adjustment, and acceptance. This article provides the physician who cares for patients with SCI with some concepts to consider when discussing prognosis with patients and their families.     

Survey of use of the insufflator-exsufflator in patients with spinal cord injury

BACKGROUND/OBJECTIVE: The insufflator-exsufflator has been shown to be effective in assisting cough in individuals with spinal cord injury. However, many institutions do not use this device. The study was performed to assess use of the device and attitudes among health care providers. METHODS: We developed a questionnaire with 4 categories of questions: knowledge of the device, type of facility, clinical practice with the device, and patient and provider satisfaction. The questionnaire was mailed to members of the American Paraplegia Society. RESULTS: Eighty-six questionnaires (16%) were returned. The device was being used in 49% of the institutions. The device was most commonly used with a tracheostomy; use did not correlate with size or type of facility. Patient and provider satisfaction with the insufflator-exsufflator was high. CONCLUSIONS: The insufflator-exsufflator is used as a means of removal of secretions in approximately one half of institutions polled. Satisfaction with the device is high.     

Psychosocial outcomes among youth with spinal cord injury by neurological impairment

Objective

Examine psychosocial outcomes of youth with spinal cord injury (SCI) as a function of neurological level (paraplegia/tetraplegia) and severity (American Spinal Injury Association (ASIA) Impairment Scale (AIS)).

Design

Survey research.

Setting

Three pediatric SCI specialty centers in the USA.

Participants

Youth with SCI ages 5–18 with neurological impairment classifications of: tetraplegia AIS ABC (tetraplegia ABC), paraplegia AIS ABC (paraplegia ABC), or AIS D.

Outcome Measures

Children''s Assessment of Participation and Enjoyment, Pediatric Quality of Life Inventory, Revised Children''s Manifest Anxiety Scale, and Children''s Depression Inventory.

Results

Three hundred and forty youth participated; 57% were male; 60% were Caucasian, 21% Hispanic, 7% African-American, 2% Native American, and 3% reported “other”. Their mean age was 8.15 years (standard deviation (SD) = 5.84) at injury and 13.18 years (SD = 3.87) at interview. Ninety-six youth (28%) had tetraplegia ABC injuries, 191 (56%) paraplegia ABC injuries, and 53 (16%) AIS D injuries. Neurological impairment was significantly related to participation and quality of life (QOL). Specifically, youth with paraplegia ABC and AIS D injuries participated in more activities than youth with tetraplegia ABC (P = 0.002; P = 0.018, respectively) and youth with paraplegia ABC participated more often than youth with tetraplegia ABC (P = 0.006). Youth with paraplegia ABC reported higher social QOL than youth with tetraplegia ABC (P = 0.001) and AIS D injuries (P = 0.002). Groups did not differ regarding mental health.

Conclusion

Interventions should target youth with tetraplegia ABC, as they may need support in terms of participation, and both youth with tetraplegia ABC and AIS D injuries in terms of social integration.     

Low-frequency fatigue in individuals with spinal cord injury

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 (P100), 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.     

Preinjury alcohol and drug use among persons with spinal cord injury: implications for rehabilitation

Context/objective

To describe preinjury alcohol and drug use and opportunities for secondary prevention among persons with recent spinal cord injury (SCI).

Design

Survey.

Setting

Acute inpatient rehabilitation program.

Participants

Participants were 118 (84.8%) of 139 consecutive admissions who met inclusion criteria and were screened for preinjury alcohol and drug use.

Interventions

None.

Outcome measures

Alcohol and drug use, toxicology results, alcohol problems, readiness to change, and treatment preferences.

Results

Participants were on average 37 years old, 84% were men, and 85% were white. Fifty-one percent of the sample was considered ‘at-risk’ drinkers. Significant lifetime alcohol-related problems were reported by 38% of the total sample. Thirty-three percent reported recent illicit drug use and 44% of the 82 cases with toxicology results were positive for illicit drugs. Seventy-one percent of at-risk drinkers reported either considering changes in alcohol use or already taking action. Forty-one percent reported interest in trying substance abuse treatment or Alcoholics Anonymous (AA). Motivation to change alcohol use was significantly and positively associated with self-reported indicators of alcohol problem severity.

Conclusion

Preinjury alcohol and drug abuse are common among persons with recent SCI. Substance abuse screening is feasible and detects not only salient clinical problems but also significant motivation to change and interest in AA or treatment, all of which represent an important window of opportunity for appropriate brief interventions and referrals. In contrast with the idea that alcoholism is a ‘disease of denial’, the majority of at-risk drinkers with new onset SCI indicate they are considering making changes.     

Evaluation of bone mineral loss in patients with chronic traumatic spinal cord injury in Iran

Objectives

We described the associations between demographic and injury-related factors on bone mineral density (BMD) of the spine and the hip among adult patients with chronic spinal cord injury (SCI).

Design

BMD in spinal and femoral bone sites were assessed. Multivariate analysis was performed to evaluate the relationship between anthropometric and injury-related factors with BMD. Serum level and amount of dietary intake of calcium, phosphor, and 25-hydroxy vitamin D were measured.

Setting

A referral tertiary rehabilitation center in Iran.

Participants

Patients with SCI who had no previous history of endocrine disorders and were not on specific medications entered the investigation. Those with non-traumatic SCI, pregnant, or with substance dependency were excluded as well.

Interventions

No interventions were applied.

Main study outcome measures

Dual X-ray absorptiometry was performed to estimate BMD. Body mass index was positively associated with higher femoral (P < 0.01, r = 0.56) and hip (P < 0.0001, r = 0.82) BMD only in female participants. The high prevalence of vitamin D deficiency (60%) was noticeable.

Results

Older male patients revealed lower BMD only in spinal vertebrae (P < 0.02, r = −0.21). A significant higher BMD loss in lumbar vertebras in male patients with complete spinal cord lesion (P < 0.009) was detected. Spinal reduction of BMD was more severe when the level of injury was above T6 (P < 0.02).

Conclusion

Along with the clarification of age, gender, post injury duration, and the other factors'' effect on the BMD in the SCI patients, here we have also shown the noticeable prevalence of the 25-hydoxy vitamin D deficiency in these patients which needs attention.     

Evaluation of bone mineral loss in patients with chronic traumatic spinal cord injury in Iran

Abstract

Objectives

We described the associations between demographic and injury-related factors on bone mineral density (BMD) of the spine and the hip among adult patients with chronic spinal cord injury (SCI).

Design

BMD in spinal and femoral bone sites were assessed. Multivariate analysis was performed to evaluate the relationship between anthropometric and injury-related factors with BMD. Serum level and amount of dietary intake of calcium, phosphor, and 25-hydroxy vitamin D were measured.

Setting

A referral tertiary rehabilitation center in Iran.

Participants

Patients with SCI who had no previous history of endocrine disorders and were not on specific medications entered the investigation. Those with non-traumatic SCI, pregnant, or with substance dependency were excluded as well.

Interventions

No interventions were applied.

Main study outcome measures

Dual X-ray absorptiometry was performed to estimate BMD. Body mass index was positively associated with higher femoral (P < 0.01, r = 0.56) and hip (P < 0.0001, r = 0.82) BMD only in female participants. The high prevalence of vitamin D deficiency (60%) was noticeable.

Results

Older male patients revealed lower BMD only in spinal vertebrae (P < 0.02, r = ?0.21). A significant higher BMD loss in lumbar vertebras in male patients with complete spinal cord lesion (P < 0.009) was detected. Spinal reduction of BMD was more severe when the level of injury was above T6 (P < 0.02).

Conclusion

Along with the clarification of age, gender, post injury duration, and the other factors' effect on the BMD in the SCI patients, here we have also shown the noticeable prevalence of the 25-hydoxy vitamin D deficiency in these patients which needs attention.     

Preinjury alcohol and drug use among persons with spinal cord injury: Implications for rehabilitation

Abstract

Context/objective

To describe preinjury alcohol and drug use and opportunities for secondary prevention among persons with recent spinal cord injury (SCI).

Design

Survey.

Setting

Acute inpatient rehabilitation program.

Participants

Participants were 118 (84.8%) of 139 consecutive admissions who met inclusion criteria and were screened for preinjury alcohol and drug use.

Interventions

None.

Outcome measures

Alcohol and drug use, toxicology results, alcohol problems, readiness to change, and treatment preferences.

Results

Participants were on average 37 years old, 84% were men, and 85% were white. Fifty-one percent of the sample was considered ‘at-risk’ drinkers. Significant lifetime alcohol-related problems were reported by 38% of the total sample. Thirty-three percent reported recent illicit drug use and 44% of the 82 cases with toxicology results were positive for illicit drugs. Seventy-one percent of at-risk drinkers reported either considering changes in alcohol use or already taking action. Forty-one percent reported interest in trying substance abuse treatment or Alcoholics Anonymous (AA). Motivation to change alcohol use was significantly and positively associated with self-reported indicators of alcohol problem severity.

Conclusion

Preinjury alcohol and drug abuse are common among persons with recent SCI. Substance abuse screening is feasible and detects not only salient clinical problems but also significant motivation to change and interest in AA or treatment, all of which represent an important window of opportunity for appropriate brief interventions and referrals. In contrast with the idea that alcoholism is a ‘disease of denial’, the majority of at-risk drinkers with new onset SCI indicate they are considering making changes.     

Associations between vitamin D and pulmonary function in chronic spinal cord injury

Context/Objective: Individuals with chronic spinal cord injury (SCI) have an increased risk of morbidity and mortality attributable to respiratory diseases. Previous studies in non-SCI populations suggest that vitamin D may be a determinant of respiratory health. Therefore, we sought to assess if lower vitamin D levels were associated with decreased pulmonary function in persons with chronic SCI.

Design: Cross-sectional study.

Setting: Veterans Affairs Medical Center.

Participants: 312 participants (260 men and 52 women) with chronic SCI recruited from VA Boston and the community participating in an epidemiologic study to assess factors influencing respiratory health.

Methods: Participants provided a blood sample, completed a respiratory health questionnaire, and underwent spirometry. Linear regression methods were used to assess cross-sectional associations between plasma 25-hydroxyviatmin D and spirometric measures of pulmonary function.

Outcome Measures: Forced expiratory volume in one second (FEV₁), forced vital capacity (FVC), and FEV₁/FVC.

Results: Adjusted and unadjusted for a number of confounders, there was no significant association between plasma vitamin D levels and FEV₁, FVC, or FEV₁/FVC. For example, in fully adjusted models, each 10?ng/ml increase in vitamin D was associated with a 4.4?ml (95%CI ?64.4, 73.2, P?=?0.90) ml change in FEV_1.

Conclusion: There was no significant cross-sectional association between plasma vitamin D and FEV₁, FVC, or FEV₁/FVC in this cohort of individuals with chronic SCI.