Surgery For Spinal Cord Injury Research Articles

Spinal cord injury in neonates alters respiratory motor output via supraspinal mechanisms

Upper cervical spinal cord injury (SCI) alters respiratory output and results in a blunted respiratory response to pH/CO 2. Many SCI studies have concentrated on respiratory changes in neural function caudal to injury; however few have examined whether neural plasticity occurs rostral to SCI. Golder et al. (2001a) showed that supraspinal changes occur to alter respiratory output after SCI. Furthermore, Brown et al. (2004) showed that neural receptors change rostral to a thoracic SCI. We hypothesized that SCI in neonates will alter supraspinal output, show a blunted response to pH and alter receptor protein levels in the medulla. On postnatal day 0/1, a C2 SCI surgery was performed. Two days later, neonates were anesthetized and brainstem-spinal cords removed. Respiratory-related activity was recorded using the in vitro brainstem-spinal cord preparation and the superfusate pH was changed (pH 7.2, 7.4 and 7.8). The respiratory-like frequency was significantly reduced in SCI rats indicating supraspinal plasticity. Increasing the pH decreased respiratory-like frequency and peak amplitude in injured and sham controls. Increasing the pH increased burst duration and area in sham controls, whereas in injured rats, the burst duration and area decreased. Western blot analysis demonstrated significant changes in glutamate receptor subunits (NR1, NR2B and GluR2), adenosine receptors (A1, A2A), glutamic acid decarboxylase (65) and neurokinin-1 receptors in medullary tissue ipsilateral and contralateral to injury. These data show that supraspinal plasticity in the respiratory system occurs after SCI in neonate rats. The mechanisms remain unknown, but may involve alterations in receptor proteins involved in neurotransmission.

Changes in Bone Mass, Bone Structure, Bone Biomechanical Properties, and Bone Metabolism after Spinal Cord Injury: A 6-Month Longitudinal Study in Growing Rats

Spinal cord injury (SCI) results in a great decline in bone mineral density (BMD) and deterioration of bone microarchitecture. The objective of this study was to investigate the time course of the changes in BMD, microarchitecture, biomechanical properties, and bone turnover in male growing rats following SCI. Sixty male growing Sprague-Dawley rats, 6 weeks of age, were randomly divided into SCI (lower thoracic cord transection) and sham-operated groups, and bone tissues and blood samples were examined at 3 weeks, 6 weeks, and 6 months after surgery. SCI rats had low bone weight (wet, dry, and ash weight) and BMD of the femora, tibiae, and third lumbar vertebrae at all time points compared to sham rats, while in forelimbs, there was a decrease of dry and ash weight compared to sham rats only at 3 weeks but not BMD. Bone microarchitecture and trabecular connectivity were deteriorated in SCI rats and remained so after. Bone formation rate and serum osteocalcin level in SCI rats were significantly increased 3 weeks after SCI surgery. However, eroded surface/bone surface and serum N-terminal telopeptide of type I collagen level remained elevated from 3 weeks to 6 months. In addition, SCI rats showed poor biomechanical properties in the proximal tibiae and femora but not in the humeri. In conclusion, SCI causes profound BMD loss, disturbances in bone microarchitecture, decreased mechanical strength in the lower extremity and lumbar spine, and high bone turnover. These findings will allow better understanding of osteoporosis following SCI.

Immune Regulatory Mechanisms Influence Early Pathology in Spinal Cord Injury and in Spontaneous Autoimmune Encephalomyelitis

Injuries to the central nervous system (CNS) trigger an inflammatory reaction with potentially devastating consequences. In this report we compared the characteristics of the inflammatory response on spinal cord injury (SCI) caused by a stab wound between the T7 and T9 vertebrae and spontaneous experimental autoimmune encephalomyelitis (EAE). SCI and EAE were compared in two types of myelin basic protein Ac1-11-specific T-cell receptor transgenic mice: T/R+ mice harbor regulatory T cells, and T/R- mice lack regulatory T cells. Our results show that 8 days after SCI, T/R- mice developed a strong T-cell infiltrate in the spinal cord, with remarkable down-modulation of CD4 expression that was accompanied by a local increase in Mac-3+ and F4/80+ reactivity and diffuse local and distal astrogliosis. In contrast, T/R+ mice exhibited a modest increase in CD4+ cells localized to the site of injury, without CD4 down-modulation; focal astrogliosis was restricted to the site of the lesion, although Mac-3+ and F4/80+ cells were also present. Similarly to T/R- mice that underwent SCI, T cells displaying down-modulated CD4 expression were found in the CNS of older T/R- mice afflicted by spontaneous EAE. Overall, our results suggest that common mechanisms regulate T-cell accumulation in CNS lesions of different causes, such as mechanic lesion or autoimmune-mediated damage.

Chronic Instrumentation With Model Microstimulators in an Animal Model of the Lower Urinary Tract

Background: Microstimulators are a new type of neuroprosthetic device that should be considered for applications such as micturition control after spinal cord injury (SCI). These devices are small (less than 25 mm by 5 mm) and the electrodes are located on the ends of the stimulator. The aim of the current study was to develop methods for chronic implantation of model microstimulators (M–Micro) on the bladder wall and pelvic plexus of female cats. A postmortem evaluation of the effects of 3 months of implantation is reported.Methods: Techniques to produce the M–Micro are described. Four of these devices were implanted in 4 female cats and maintained after the initial instrumentation surgery and a second survival surgery for SCI (at Tl 0). Using a single suture tied around the M–Micro,these deviceswere secured to the bladder wall or the fat pads adjacent to the pelvic plexus. Additional instrumentationwas implanted, including 2 catheters in the bladder, 1 abdominal balloon,and electromyography electrodes in the urethral and anal sphincters. Postmortem observations of the location of the M–Micro on the bladder wall were conductedafter fixation.Results: The animals´ conditions were good. One animal was sacrificed early because of a skin infection. A single suture was sufficient to anchor the M-Micro. However, during thesurgical implantation the pelvic plexus M–Micro ended up close to the bladder neck.Extensive fibrous connective tissue formed around the M-Micro and implanted catheterson the bladder wall. This appeared to result, in part, from multiple devices implanted onor nearthe bladder wall.Conclusions: These pilot studies showed that the M–Micro could be easily constructed and secured to the bladder wall or fat pads close to the pelvic plexus. There was a concern that the pelvic plexus location for the M–Micro ended near the bladder neck during the surgical implantation; however, these devices did not appear to migrate over this short, 3–month implantation period. The extensive connective tissue responses of the bladder wall to the tubes, wires, and M-Micro was a major concern. The M–Micro appears to be a good device to assess the potential of commercial microstimulators for use in micturition control.

Occurrence of limb movement during sleep in rats with spinal cord injury

Several studies have shown the occurrence of Periodic Leg Movement (PLM) in spinal cord injury patients. The aim of this study was to identify the occurrence of limb movements during sleep in spinal cord injury rats and the possible involvement of the spinal cord in causing these movements. The animals were allocated to spinal cord injury (SCI) and SHAM groups. The two groups were submitted to surgery and electrodes inserted to analyze sleep patterns (electroencephalogram—ECoG) and muscular activity patterns (eletromyogram—EMG). After baseline sleep recording (24 h), the spinal cord injury surgery (level T9) was performed on the SCI group rats and sleep was recorded for seven consecutive days. After spinal cord injury, 10 of the 11 rats began to present limb movements during sleep, while the SHAM group showed no limb movements during the 8-day sleep-recording period. In relation to sleep efficiency, the SCI group presented alterations during the first few days after spinal cord injury but returned to normal values at the end of the 7-day experimental period. The data suggest that spinal cord injury rats may be used as models to study PLM in paraplegic patients, and that these movements may be generated in the spinal cord itself, without the involvement of the cortical structures.

Assessment of Quality of Life and Psychological Status in Spinal Cord Injury after Spinal Fracture

Study design: A retrospective study Objectives: To study the socio-psychological adaptation through the psychoanalysis in the patients with spinal cord injury. Materials and Methods : From May 1998 to Aug. 2003 we chose the 15 patients who have been undergone surgery for spinal cord injury after spinal fracture. Psycological analysis were based on the Korean version of Beck Depression Index(K-BDI), Hamilton Anxiety Scale, and the Minnesota Multiphasic Personality Inventory(MMPI), and valuation of quality of life. R e s u l t s: K-BDI applied results showed an average of 33.5±10.3, having a higher average than normal. Hamilton Anxiety Scale resulted with an average of 32.4±9.4. 4 patients were taken intensive care psychologically beause of depression. The Lie score out of the MMPI’s suitability scale showed 43.3±9.7, Validity score as 75.4±23.6, and Defensiveness score with 47.7± 10.6 as average and standard deviation, resulting a higher as to normal. Further more, clinical scales of Hypochondriasis scale was 69.9±12.6, Depression as 65.5±15.3, Hysteria scale as 67.9±11.5, Psychopathic deviate as 65.6±12.1, Paranonia as 71.9± 17.6, Psychasthenia scale as 67.9±12.3, Schizophrenia as 70.4±17.8, Hypomania scale as 54.0±11.3, and social introversion scale as much as 60.1±15.0 higher than normal. In evaluation the quality of life, there was a prominent issue in the occupation(0.1) and economic independence(0.5) out of the total 6 items, difference was 0.6, social adaptation was 0.8, physical independence was 0.7 and orientation(1.6) was similar to normal person. Conclusion: As the physical and the psychological changes abrupt at the same time with the spinal cord injury, it is important to encourage the patients to have a strong ego to have an optimistic confidence of recuperation.

Bladder Stones Following Sci In The Sprague-Dawley Rat

Objective: To develop a spinal cord injury (SCI) animal model for the study of bladder stones and compare this model with a non-SCI animal model.Methods: Small pieces of catheters were implanted into the bladders of Sprague-Dawley rats as a nidus for bladder stone formation. Three weeks later, the rats underwent an SCI surgery (SCI transection or sham SCI). Control rats had SCI surgery, but no catheters were implanted into their bladders.Main Outcome Measures: Bladder stone number, weight, and composition were determined in two groups of SCI and sham SCI animals: Group A (recent spinal shock: 2 weeks post-SCI/sham SCI surgery) and Group B(out of spinal shock: 3 weeks to 3 months post-SCI/sham SCI surgery). AX2 test was used to compare the incidence of bladder stones in SCI vs sham SCI animals. AStudent t test was used to compare the weight of bladder stones in the 2 groups.Results: Group A(recent spinal shock): Of the 20 SCI rats, 8 (40%) had stones. None of the sham SCI rats with implanted catheters (n = 5) had stones (0%). Group B(out of spinal shock): All 6 of the SCI rats with implanted catheters had stones (100%). Of the 10 sham SCI animals with implanted catheters, 3 (30%) had stones. Stones were more common in the SCI rats than in the sham SCI rats (X2., = 4.9, P < 0.05). The mean weight of the bladder stones in SCI rats (42.2 ± 16.3 mg) was greater than that in sham SCI rats (5.4 ± 1.5 mg) (P < 0.01). Group C (controls: SCI surgery, but no catheter implanted): At 3 weeks post-SCI, control rats had no stones (n = 7); control rats at 3 months post-SCI also had no stones (n = 9). Stone composition in the 3 sham SCI animals was calcium apatite (90%) and calcium oxylate (10%). In the 14 SCI rats, 10 had struvite stones (1 00%), 1 had struvite (70%) and carbonate apatite (30%) stones, 1 had brushite (100)% stones, and 2 had carbonate apatite (>90%) stones.Conclusion: Bladder stones occurred earlier and more frequently and attained a larger size in SCI rats with catheters compared with sham SCI rats with catheters. There were no stones in SCI rats without catheter implants, even at 3-month follow-up. The bladder stone composition in SCI rats was similar to that in humans with SCI. The Sprague-Dawley rat model appears to be an excellent animal model for the study of bladder stones following SCI.J Spinal Cord Med. 2003;26:65-68

EFFECTS OF TESTOSTERONE REPLACEMENT THERAPY ON RAT SKELETAL MUSCLE AFTER SPINAL CORD INJURY.

Spinal cord injury (SCI) is associated with increased risks for development of several diseases, for example diabetes, that are probably linked to the extreme atrophy of affected skeletal muscle. If testosterone replacement therapy (TRT) alone or as an adjunct to other therapies could attenuate the atrophy, these risks might be reduced. PURPOSE: To examine the effects of TRT on rat skeletal muscle 11 weeks after SCI. METHODS: The soleus (SOL) was taken from twelve young male Charles River rats 11 weeks after SCI (T-9 laminectomy, n = 8) or sham surgery (n = 4). Rats received either testosterone (2, 5 cm testosterone capsules, n = 4), or saline implantation (n = 8) at the time of surgery. Muscle samples were sectioned and fibers analyzed qualitatively for myosin ATPase and quantitatively for succinate dehydrogenase (SDH) and α -glycerol-phosphate dehydrogenase (GPDH) activities using standard techniques. RESULTS: SCI decreased (P < 0.05) average fiber size 49 ± 4% and the percentage of slow fibers from 93 ± 3 to 17 ± 2%These responses were accompanied by a decrease in SDH and an increase in GPDH activities. TRT after SCI attenuated the fiber atrophy, the slow to fast fiber conversion as well as the changes in SDH and GPDH activity. Average fiber size was decreased by only 30% in TRT SCI animals and their soleus had 39 ± 2% slow fibers. CONCLUSIONS: TRT was effective in attenuating alterations in myofibrillar proteins during 11 weeks of SCI. Supported by NIH HD-33738

Alteration of follicle-stimulating hormone and testosterone regulation of messenger ribonucleic acid for Sertoli cell proteins in the rat during the acute phase of spinal cord injury.

The detrimental effects of spinal cord injury (SCI) on spermatogenesis in the rat can be attenuated by exogenous testosterone (T) but enhanced by exogenous follicle-stimulating hormone (FSH). These results suggest that T-dependent cellular events may be involved in testicular injury after SCI and that such events may be associated with modification of FSH effects on Sertoli cell function. The current study compared the responses of Sertoli cells to exogenous T and FSH after SCI or sham surgery using steady-state levels of Sertoli cell protein mRNA transcripts as markers of responsiveness. Rats underwent sham surgery or SCI and then were treated for 7 or 14 days with T-filled silastic capsules (2 x 5 cm) and/or daily injections of 0.1 units of porcine FSH. Vehicle-treated control rats received 5-cm empty capsules and daily injections of saline vehicle. Two weeks after sham surgery, levels of mRNA for the androgen receptor (AR), FSH receptor (FSHR), androgen-binding protein (ABP), or sulfated glycoprotein (SGP)-2 in the testis were unaffected by T or FSH alone. Testosterone alone, however, significantly decreased transferrin (Trf) mRNA levels in the testis (P: < 0.01). The combination of T and FSH treatments resulted in significant decreases in levels of the above transcripts (P: < 0.05; P: < 0.01). Seven days after SCI, the testes of vehicle-treated SCI rats had higher levels of AR and SGP-2 mRNA than did those of sham control rats (P: < 0.01); such effects were transient and disappeared by Day 14 post-SCI. Testosterone treatment of SCI rats for 7 days resulted in decreases in mRNA levels for AR and Trf in the testes (P: < 0.01) but increased testicular levels of mRNAs for FSHR and SGP-2 in SCI rats. Follicle-stimulating hormone treatment for 7 days prevented the increase in AR mRNA that was seen in the testis of untreated SCI rats and increased levels of ABP and SGP-2 mRNAs in SCI rats (P: < 0.01). Follicle-stimulating hormone treatment of SCI rats did not affect FSHR mRNA levels by itself, but it blocked the stimulatory effect of T on FSHR and SGP-2 mRNAs. Fourteen days after SCI, testicular AR mRNA levels were not affected by T alone, but they increased in those rats that received FSH with or without concurrent T treatments (P: < 0.05). In contrast to their effects in sham control rats, T or FSH alone or in combination resulted in significant increases in testicular levels of ABP, SGP-2, and FSHR mRNAs (P: < 0.05). At this time, Trf mRNA in the testis of SCI rats was also suppressed by T (P: < 0.05), as it did in sham control rats, but Trf mRNA was increased by the FSH (P: < 0.01) that had inhibited this transcript in the testes of sham control rats. The effects of FSH on the Sertoli cell transcripts in SCI rats were either attenuated or blocked when T was given concurrently. In addition, testicular and serum T levels in those SCI rats that received FSH (alone or in combination with T) for 14 days were significantly increased, an effect that was not seen after sham surgery. These findings demonstrate that hormonal regulation of both Sertoli and Leydig cells was altered during the acute phase of SCI. Such changes may modify the functions of both cell types, thereby affecting the endocrine and/or paracrine microenvironment within the seminiferous epithelium. These effects could impair the functional capacity of Sertoli cells and contribute to impairment of spermatogenesis after SCI.

An evidence-based review of surgical decompression for acute spinal cord injury: rationale, indications, and timing based on experimental and clinical studies

The authors conducted an evidence-based review of the literature to evaluate critically the rationale and indications for and the timing of decompressive surgery for the treatment of acute, nonpenetrating spinal cord injury (SCI). The experimental and clinical literature concerning the role of, and the biological rationale for surgical decompression for acute SCI was reviewed. Clinical studies of nonoperative management of SCI were also examined for comparative purposes. Evidence from clinical trials was categorized as Class I (well-conducted randomized prospective trials), Class II (well-designed comparative clinical studies), or Class III (retrospective studies). Studies in which animal models of SCI were used consistently demonstrated a beneficial effect of early surgical decompression, although it is difficult to apply these data directly to the clinical setting. The clinical studies provided suggestive (Class III and limited Class II) evidence that decompressive procedures improve neurological recovery after SCI. However, no clear consensus can be inferred from the literature as to the optimum timing of decompressive surgery. Many authors have advocated delayed treatment to avoid medical complications, although there is good evidence from recent Class II trials that early decompressive surgery can be performed safely without added morbidity or mortality. There is biological evidence from experimental studies in animals that early surgical decompression may improve neurological recovery after SCI, although the relevant interventional timing in humans remains unclear. To date, the role of surgical decompression in patients with SCI is only supported by Class III and limited Class II evidence. Accordingly, decompressive surgery for SCI can only be considered a practice option. Furthermore, analysis of the literature does not allow definite conclusions to be drawn regarding appropriate timing of intervention. Hence, there is a need to conduct well-designed experimental and clinical studies of the timing and neurological results of surgical decompression for the treatment of acute SCI.

Fundamental and applied aspects of space - time organisation of iron metabolism in pregnancy

Upper cervical spinal cord injury (SCI) alters respiratory output and results in a blunted respiratory response to pH/CO2. Many SCI studies have concentrated on respiratory changes in neural function caudal to injury; however few have examined whether neural plasticity occurs rostral to SCI. Golder et al. (2001a) showed that supraspinal changes occur to alter respiratory output after SCI. Furthermore, Brown et al. (2004) showed that neural receptors change rostral to a thoracic SCI. We hypothesized that SCI in neonates will alter supraspinal output, show a blunted response to pH and alter receptor protein levels in the medulla. On postnatal day 0/1, a C2 SCI surgery was performed. Two days later, neonates were anesthetized and brainstem-spinal cords removed. Respiratory-related activity was recorded using the in vitro brainstem-spinal cord preparation and the superfusate pH was changed (pH 7.2, 7.4 and 7.8). The respiratory-like frequency was significantly reduced in SCI rats indicating supraspinal plasticity. Increasing the pH decreased respiratory-like frequency and peak amplitude in injured and sham controls. Increasing the pH increased burst duration and area in sham controls, whereas in injured rats, the burst duration and area decreased. Western blot analysis demonstrated significant changes in glutamate receptor subunits (NR1, NR2B and GluR2), adenosine receptors (A1, A2A), glutamic acid decarboxylase (65) and neurokinin-1 receptors in medullary tissue ipsilateral and contralateral to injury. These data show that supraspinal plasticity in the respiratory system occurs after SCI in neonate rats. The mechanisms remain unknown, but may involve alterations in receptor proteins involved in neurotransmission.

Surgery for Spinal Cord Injuries. (Principles and Techniques in Spine Surgery Series)

Surgery for Spinal Cord Injuries. (Principles and Techniques in Spine Surgery Series)

Surgery for Spinal Cord Injuries. Principles and Techniques in Spine Surgery.

Surgery for Spinal Cord Injuries. Principles and Techniques in Spine Surgery.