| Spinal Cord 2004 Abstracts （www.nature.com/sc ） （Jan-June 2004） |
■ March 2004, Volume 42, Number 3
1Department of Kinesiology, McMaster University, Ontario, Canada 2Department of Nuclear Medicine, Hamilton Health Sciences, Hamilton, Ontario, Canada
Speed of sound in bone at the tibia: is it related to lower limb bone mineral density in spinal-cord-injured individuals? L M Giangregorio1 and C E Webber2
Study design: A cross-sectional study evaluating BMD at the hip and tibia, and SOS at the radius and mid-tibia in individuals with spinal cord injury (SCI) and a subgroup of non-SCI individuals.
Objectives: To investigate the speed of sound (SOS) in bone in relation to bone mineral density (BMD).
Setting: Kinesiology Department, McMaster University, Ontario, Canada.
Methods: In 14 individuals with SCI and 10 non-SCI individuals, proximal femur and tibia BMD were measured using dual energy X-ray absorptiometry, and radius and tibia SOS were measured with an ultrasonometer. T-scores were calculated using healthy reference databases. Inter-relationships between measurement techniques were determined using Pearson's correlation coefficients. P-values less than 0.05 were considered statistically significant.
Results: The average ages of the SCI and non-SCI groups were 33±9 and 27±6 years, respectively. Lesion level ranged from C4 to T12 and average time postinjury was 12 years, with a range of 1.6±25 years. Using the WHO criteria for osteoporosis, nine of 14 SCI subjects were osteoporotic at the hip, with the remainder in the osteopenic range. Tibia SOS T-scores were in the osteoporotic range for one subject with SCI, and two were in the osteopenic range. Among non-SCI individuals, one male had a tibia SOS T-score of -1.4, all others were within the normal range. Hip BMD and tibia SOS were significantly correlated (r=0.46, P<0.01). Hip BMD and tibia BMD were more strongly correlated (r=0.80, P<0.0005). Tibia BMD was not significantly correlated with SOS at the tibia (r=0.35, P=0.09). Radius SOS T-scores were positive and not significantly correlated with any lower limb variable.
Conclusion: Lower-limb bone mass is reduced in spinal cord-injured individuals, but SOS at the mid-tibia is not. It remains to be determined whether ultrasound measurements can predict fracture in the SCI population.
1Shriners Hospitals for Children, Philadelphia, PA, USA
Implantation of the Freehand SystemO during initial rehabilitation using minimally invasive techniques M J Mulcahey1, R R Betz1, S H Kozin1, B T Smith1, D Hutchinson1 and C Lutz1
Study design: Series of four single subjects with and without intervention design.
Objectives: To describe a minimally invasive surgical technique used to implant the Freehand SystemR) during initial spinal cord injury (SCI) rehabilitation and to report rehabilitation outcomes of four recently injured adolescents using the Freehand SystemR).
Setting: Nonprofit children's hospital specializing in orthopedic and SCI care.
Methods: Four subjects with C5 tetraplegia between 13 and 16 years of age and between 9 and 16 weeks following traumatic SCI underwent implantation of the Freehand SystemR) using minimally invasive surgical techniques. Outcomes on muscle strength, pinch force, hand function, performance of activities of daily living and satisfaction with and without the Freehand SystemR) were collected.
Results: Each subject was successfully implanted with the Freehand SystemR) without perioperative complications and employed the Freehand SystemR) during therapy services and ad lib on the rehabilitation floor. At the last follow-up, every subject remained a motor candidate for the Freehand SystemR). With the Freehand SystemR), average lateral and palmar pinch force was 1.8 and 1.6 kg respectively; average pinch force without functional electrical stimulation (FES) was 0.29 kg. With the Freehand SystemR), three subjects improved their rate of performance on The Upper Extremity Capabilities Questionnaire. All subjects increased their level of independence on The Quadriplegia Index of Function. On the Canadian Occupational Performance Measure (COPM) with the Freehand SystemR), average performance and satisfaction scores improved for every patient. Three of the four subjects continued to use the system at home.
Conclusion: This case series demonstrates that the Freehand SystemR) can vastly improve hand function and performance of rehabilitation activities within days after a minimally invasive implant procedure during initial SCI rehabilitation. Satisfaction with the Freehand SystemR) beyond initial rehabilitation is evidenced by continued use at home.
Sponsorship: Shriners Hospitals for Children.
1Rehabilitation Research Laboratory, GF Strong Rehab Centre, Vancouver, BC, Canada 2School of Rehabilitation Sciences, University of British Columbia, Vancouver, BC, Canada 3International Collaboration on Repair Discoveries, Vancouver, BC, Canada 4Spinal Cord Injury Program, GF Strong Rehab Centre, Vancouver, BC, Canada
Level walking and ambulatory capacity in persons with incomplete spinal cord injury: relationship with muscle strength C M Kim1,2, J J Eng1,2,3 and M W Whittaker1,4
Study design: Prospective analysis of relationships.
Objectives: (1) To quantify the relationship between individual lower extremity muscle strength and functional walking measures and (2) to determine whether a multiple regression model incorporating lower extremity muscle strength could predict the performance of functional walking measures in persons with incomplete spinal cord injury (ISCI) living in the community.
Setting: Tertiary rehabilitation center, Vancouver, Canada.
Methods: In all, 22 subjects with ISCI participated. The relationship between functional walking measures (gait speed, 6-min-walk distance, and ambulatory capacity) and muscle strength (manual tests of hip flexors/extensors/abductors, knee flexors/extensors, ankle dorsiflexors/plantarflexors, and great toe extensors) were measured by Pearson's correlation and regression procedures.
Results: For both the more and less affected sides, hip flexors, hip extensors, and hip abductors produced the highest correlations with the three functional measures. The less affected hip flexor strength explained more than 50% of the variance in gait speed and 6-min-walk distance while the less affected hip extensor strength explained up to 64% of the variance in ambulatory capacity. For all three functional measures, the strength of the less affected limb was more important than that of the more affected limb.
Conclusions: Lower extremity muscle strength, in particular that of hip flexors, hip extensors, and hip abductors, is an important determinant of functional walking performance.
1Departments of Pediatrics and Pathology, University of Virginia, Charlottesville, VA, USA 2Department of Urology, Children's Medical Center, Seattle, WA, USA
Bladder epithelium is abnormal in patients with neurogenic bladder due to myelomeningocele T A Schlager1, R Grady2, S E Mills1 and J O Hendley1
Objective: To describe the urothelium of the neurogenic bladder in patients with myelomeningocele on clean intermittent catheterization.
Setting:Outpatient practice.
Methods: Samples of bladder wall obtained from two groups of patients were examined for urothelium. The first group included 12 children and young adults with myelomeningocele and neurogenic bladder on intermittent catheterization for bladder emptying. The second group included eight children with vesicoureteral reflux and non-neurogenic bladder. Nine patients from the first group and four patients from the second group had urothelium. A contiguous section of each of the 13 samples with urothelium was stained for uroplakin expression, a marker of superficial bladder urothelium by immunohistochemistry.
Results: Samples from children with reflux revealed normal bladder epithelium and a uniform layer of umbrella cells (95% CI: 0-60%). In contrast, the epithelium from all patients with myelomeningocele was abnormal (95% CI: 66-100%). Epithelium from five patients (four children, one adult) revealed chronic inflammation. Three patients (two children, one adult) had squamous metaplasia. The apical surface of the epithelium in all patients with chronic inflammation had some reactivity with anti-uroplakin antibody, but the cells staining positive for uroplakin were scattered along the lumenal surface of the epithelium. The apical surface of patients with squamous metaplasia was negative for uroplakin.
Conclusion: The urothelium of the neurogenic bladder in young patients with myelomeningocele is abnormal, with loss of uroplakin expression and altered urothelial proliferation.
1The Cleveland Functional Electrical Stimulation Center, Louis B Stokes Veterans Affairs Medical Center, Cleveland, OH, USA 2MetroHealth Medical Center, Cleveland, OH, USA 3Case Western Reserve University, Cleveland, OH, USA
Perceived outcomes and utilization of upper extremity surgical reconstruction in individuals with tetraplegia at model spinal cord injury systems A M Bryden1, K S Wuolle1, P K Murray2 and P Hunter Peckham1,2,3
Study design: Survey.
Objective: To measure the utilization of upper extremity reconstructive surgery and the clinicians' perceptions of the outcomes provided for persons with tetraplegia across the Model Spinal Cord (SCI) Injury Systems.
Setting: Model SCI Systems.
Methods: Participants: A clinician from each of the Model Centers. Main outcome measure: A mailed survey eliciting responses with respect to: (1) utilization of upper extremity reconstructive procedures and (2) the clinicians' perceived outcomes of these procedures.
Results: In all, 76% responded positively about the availability and appropriateness of upper extremity surgical reconstruction at their center. Of the respondents, 75% felt that surgery recipients were generally satisfied with their surgeries, 80% felt that the surgery made a positive impact on recipients' lives, 81% felt that recipients showed increased independence, and 70% reported a positive impact on recipients' occupation. In all, 93% felt insurance companies should pay for the procedures. Compared to the satisfaction of surgery recipients using a similar instrument, clinicians anticipated slightly greater improvements in all areas except occupation.
Conclusions: There is a positive perception of the benefits of reconstructive surgery for tetraplegia; however, procedures are not routinely offered at all centers. The primary reasons reported for this include the misconception that insurance does not remit payment, that a surgeon is not available, and that surgical candidates are referred to another center.
Sponsorship: Support was provided by the United States Department of Education, National Institute on Disability and Rehabilitation Research. Award # H133N50018, Rehabilitation Research and Development Center of Excellence in Functional Electrical Stimulation Department of Veterans Affairs.
1Centre for Rehabilitation, University Hospital Groningen, Groningen, The Netherlands 2Northern Centre for Health Care Research, University of Groningen, The Netherlands
Vocational reintegration following spinal cord injury: expectations, participation and interventions M C Schonherr,2, J W Groothoff2, G A Mulder1, T Schoppen1,2 and W H Eisma1,2
Study design: Survey.
Objectives: To explore the process of reintegration in paid work following a traumatic spinal cord injury (SCI), including the role of early expectations of individual patients regarding return to work, indicators of success of job reintegration and a description of reintegration interventions and barriers.
Setting: Dutch rehabilitation centre with special department for patients with spinal cord injuries.
Methods: Descriptive analysis of data gathered by a mailed questionnaire, which was returned by 57 persons (response 83%) with traumatic SCI, aged 18-60 years, and data of earlier expectations reported by the individual patients during the rehabilitation admission following SCI from 1990 to 1998.
Results: Of 49 respondents who were employed at the moment of the SCI, 45% expected to be able to resume work. These positive expectations were associated with a higher educational level. In 67%, return to work was successful. The chance to reintegrate successfully was better if the patient expected to resume work. Logistic regression analysis did not reveal other significant indicators. About one-third of the 49 respondents working preinjury followed vocational retraining, which was successful for most of them so far. In the majority of work situations modifications have been made, such as job adaptations and reduction of working hours. Several unmet needs regarding reintegration interventions were also reported.
Conclusions: Positive expectations regarding resumption of work after a SCI are an important indicator of successful reintegration in work. An active role of the rehabilitation team is recommended in drawing up a vocational reintegration plan to prepare the patient, the employer and professionals involved in the reintegration process.
1Department of Anatomy and Physiology, Research Centre of the Laval University Medical center, Laval University, Quebec, Canada
Role of NMDA receptor activation in serotonin agonist-induced air-stepping in paraplegic mice P A Guertin1
Study design: Experimental laboratory investigation of the effects of serotonergic and glutamatergic drugs in early paraplegic mice.
Objectives: To examine whether NMDA and 5-HT receptors synergistically participate to generate basic stepping movements in paraplegic mice.
Setting: Laval University Medical Center, Quebec, Canada.
Methods: Adult mice completely spinalized at the low-thoracic level 1 week earlier were suspended in harnesses for experiments. Acute drug-induced effects were examined on hindlimb movements filmed with a digital video camera. Detailed kinematic analyses included stick diagrams reconstructions of hindlimb movements and analysis of bilateral coordination, angular excursion, stepping amplitude and frequency.
Results: A single treatment with the 5-HT2 agonist quipazine (>0.7 mg/kg, i.p.) induced episodes of air-stepping movements in the hindlimbs of paraplegic mice. In contrast, injection of the glutamatergic agonist NMDA (1-45 mg/kg i.p.) failed to induce rhythmicity, although nonlocomotor rhythmic movements were observed with higher doses (45-60 mg/kg i.p.). Subthreshold doses of NMDA (22-30 mg/kg) could induce episodes of hindlimb air-stepping if combined with subthreshold doses of quipazine (0.3-0.7 mg/kg). Air-stepping was entirely blocked by administration of the selective NMDA antagonist MK-801.
Conclusion: A single treatment with quipazine can trigger episodes of locomotor-like movements in early chronic spinal mice. Even though NMDA alone could not generate bilaterally coordinated air-stepping, NMDA receptor activation was nonetheless critical for spinal locomotor rhythmogenesis induced by 5-HT agonists in awake behaving animals.
1National Spinal Injuries Centre, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, UK 2Formerly at: Top Grade Biochemist, Ulster Hospital (Retired), 219 Orby Drive, Belfast BT5 6BE, Northern Ireland
Reduced sodium output following acute spinal injury J R Silver1 and J R Doggart1,2
Study design: Assessment of sodium output in spinal injury patients.
Objectives: The purpose was to examine the effects of sodium loading acutely by an infusion, long term by sodium supplements, to acutely injured spinal patients on a fixed sodium intake. This was compared with another group of acutely injured patients who were on a hospital diet of between 50 and 150 mmol of sodium daily.
Setting: The National Spinal Injuries Centre, Stoke Mandeville Hospital, Aylesbury, Bucks HP21 8AL, UK.
Methods: A total of 53 studies were carried out on 52 patients between 1962 and 1964. In all, 49 patients were studied during the first 10 days after injury as follows: a control group of 39 patients received no supplementary sodium, two received NaCl infusion, two NaCl tablets orally, and six received NaCl infusion followed by NaCl tablets orally. Four patients were studied for more than 15 days after injury (one of these had been studied in the acute stage); they received NaCl infusion and one (42d) received in addition NaCl tablets for four subsequent days.
Results: In all patients urinary sodium excretion was minimal on day 2 and increased thereafter. On days 2?6, it was significantly lower in patients with a complete transection of the cervical cord than in patients with lower lesions. In the early studies, nine patients excreted less than 40% of the administered load within 24 h. In four of these patients excretion was 10% or less. In the later studies, three of the four patients excreted at least 80% of the infused Na+ on the same day.
Conclusion: Sodium retention in the patient with cord injury is a response to trauma. The different responses seen in patients with different levels of cord transection are not due to direct changes in the innervation of the kidney but to compensation for sympathetic insufficiency, blood pressure being maintained by the secretion of aldosterone, vasopressin and other hormones. The decreased urinary output seen acutely after cord transection is not due to renal failure and the patient's condition can be made dangerously worse by attempts to create a diuresis.
1Department of Orthopaedic Surgery, Kagoshima Graduate School of Medical and Dental Sciences, Kagoshima, Japan 2Department of Pediatrics, Kagoshima Graduate School of Medical and Dental Sciences, Kagoshima, Japan
Primary malignant peripheral nerve sheath tumor of the cauda equina in a child case report K Yone1, K Ijiri1, K Hayashi1, M Yokouchi1, T Takenouchi1, K Manago2, Y Nerome2, O Ijichi2, N Ikarimoto2 and S Komiya1
Study design: A case report of primary malignant peripheral nerve sheath tumor (MPNST) of the cauda equina in a child is presented, and the literature is reviewed.
Objective: To discuss the problems involved in the treatment of primary intradural MPNSTs.
Setting: A department of orthopaedic surgery in Japan.
Methods: A 4-year-old boy complained of low-back pain radiating to the left calf. MRI revealed an intradural tumor at L3-L5 level. Following laminectomy of L3, L4 and L5, the tumor was removed en bloc. Based on pathological and immunohistological findings, the tumor was diagnosed as an MPNST.
Results: Although adjuvant chemotherapy was administered local recurrence and cerebral and spinal metastases of the tumor were found 6 months after the operation. Following additional incomplete removal of the recurrent tumor, radiation therapy was administered. Although recurrent and metastatic tumors disappeared or diminished in size by radiation, tumors increased in size thereafter, despite additional adjuvant chemotherapy. At 21 months after the first operation, he died of pneumonia.
Conclusions: Reported clinical outcomes for patients with primary intradural MPNST are very poor. Although no gold standard for the treatment of tumors has been established yet, surgical removal of tumors combined with postoperative high-dose radiation may be recommended.
1Spinal Cord Injury Unit, Institution of Clinical Neuroscience, Sahlgrenska Academy, Goteborg, Sweden 2ICORD, Division of Physical Medicine and Rehabilitation, University of BC, Vancouver, Canada
Hyponatremia-induced transient visual disturbances in acute spinal cord injury A-K Karlsson1 and A V Krassioukov2
Study design: Case report and literature review.
Objective: To report an unusual case of prolonged hyponatremia in acute cervical spinal cord injury complicated by visual disturbances and to review the literature regarding the issue.
Settings: Spinal Cord Injury Unit in Goteborg, Sweden.
Methods: Retrospective analysis of clinical charts of an individual with traumatic spinal cord injury.
Results: A previously healthy 28-year-old man sustained a C7 injury in a motor vehicle accident. His injury was managed surgically and he was overhydrated during the acute management and postoperatively. When weaned off the respirator he was confused and anxious and showed a S-Na of 127 mmol/1 and complained of visual disturbances. The hyponatremia was treated by extra sodium and fluid restriction but fell to a lowest value of 121 mmol/l (Day 14 post injury). Visual acuity was 0.2 on right eye and 0.06 on left eye and the eye examination revealed signs of fundus hypertonicus. CT scans and MRI revealed no signs of brain edema. The patient was further treated by mineral corticoids and fluid restriction for 4 months and his vision improved slightly, but on a final examination 125 days post injury he was found to have an afferent pupillary defect on his left eye, and bilateral atrophy of the visual nerves. The hyponatremia resolved and 6 months post injury he showed a normal S-Na.
Conclusions: SCI individuals are at increased risk of developing hyponatremia. The reported complication of visual disturbances further stresses the importance of prevention of overhydration and of timely management of hyponatremia in this group of patients.