OBJECTIVE: To evaluate T2 relaxation time change using axial T2 mapping in a rabbit degenerated disc model and determine the most correlated variable with histologic score among T2 relaxation time, disc height index, and Pfirrmann grade. MATERIALS AND METHODS: Degenerated disc model was made in 4 lumbar discs of 11 rabbits (n = 44) by percutaneous annular puncture with various severities of an injury. Lumbar spine lateral radiograph, MR T2 sagittal scan and MR axial T2 mapping were obtained at baseline and 2 weeks and 4 weeks after the injury in 7 rabbits and at baseline and 2 weeks, 4 weeks, and 6 weeks after the injury in 4 rabbits. Generalized estimating equations were used for a longitudinal analysis of changes in T2 relaxation time in degenerated disc model. T2 relaxation time, disc height index and Pfirrmann grade were correlated with the histologic scoring of disc degeneration using Spearman's rho test. RESULTS: There was a significant difference in T2 relaxation time between uninjured and injured discs after annular puncture. Progressive decrease in T2 relaxation time was observed in injured discs throughout the study period. Lower T2 relaxation time was observed in the more severely injured discs. T2 relaxation time showed the strongest inverse correlation with the histologic score among the variables investigated (r = -0.811, p < 0.001). CONCLUSION: T2 relaxation time measured with axial T2 mapping in degenerated discs is a potential method to assess disc degeneration.
Animals ; Disease Models, Animal ; Intervertebral Disc/injuries/*pathology ; Intervertebral Disc Degeneration/*pathology ; Lumbar Vertebrae/*pathology ; Magnetic Resonance Imaging/*methods ; Male ; Punctures ; Rabbits

OBJECTIVE: To evaluate spine magnetic resonance imaging (MRI) inter-reader and intra-reader reliabilities using the thoracolumbar injury classification system and severity score (TLICS) and to analyze the effects of reader experience on reliability and the possible reasons for discordant interpretations. MATERIALS AND METHODS: Six radiologists (two senior, two junior radiologists, and two residents) independently scored 100 MRI examinations of thoracolumbar spine injuries to assess injury morphology and posterior ligamentous complex (PLC) integrity according to the TLICS. Inter-reader and intra-reader agreements were determined and analyzed according to the number of years of radiologist experience. RESULTS: Inter-reader agreement between the six readers was moderate (k = 0.538 for the first and 0.537 for the second review) for injury morphology and fair to moderate (k = 0.440 for the first and 0.389 for the second review) for PLC integrity. No significant difference in inter-reader agreement was observed according to the number of years of radiologist experience. Intra-reader agreements showed a wide range (k = 0.538-0.822 for injury morphology and 0.423-0.616 for PLC integrity). Agreement was achieved in 44 for the first and 45 for the second review about injury morphology, as well as in 41 for the first and 38 for the second review of PLC integrity. A positive correlation was detected between injury morphology score and PLC integrity. CONCLUSION: The reliability of MRI for assessing thoracolumbar spinal injuries according to the TLICS was moderate for injury morphology and fair to moderate for PLC integrity, which may not be influenced by radiologist' experience.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Humans ; *Injury Severity Score ; Ligamentum Flavum/pathology ; Lumbar Vertebrae/*injuries/pathology ; Magnetic Resonance Imaging/*methods ; Male ; Middle Aged ; Observer Variation ; Reproducibility of Results ; Retrospective Studies ; Spinal Injuries/*classification/*pathology ; Thoracic Vertebrae/*injuries/pathology ; Thoracic Wall/pathology ; Young Adult

Lumbar intervertebral disc herniation clinical symptoms and signs are very complicated, lumbocrural pain is the most characteristic clinical symptoms,and show the site (range or area), intensity, nature, evolution, influence factors and adjoint symptoms and so on has certain characteristics and rules. Among them, the dermatomal pain, kinesthetic dysesthesia, dynamic changing pain and lesions segment vertebral side deep tenderness are the most impotent characteristics and rules of pain, therefore, can be regarded as the main basis of clinical diagnosis of the disease, and also the core content of this article.
Back Pain ; diagnosis ; etiology ; pathology ; Humans ; Intervertebral Disc Displacement ; diagnosis ; pathology ; Lumbar Vertebrae ; injuries ; pathology

OBJECTIVETo compare the long-term influence of vertebral fixation through or across the affected vertebra on vertebral morphology.

METHODSClinical data of 48 patients with simple thoracic and lumbar spinal fractures who were admitted between Jan. 2008 and Dec. 2010 were analyzed retrospectively. Among them 36 cases (28 males and 8 females) were fixed through the injured vertebra (group A) and 12 cases (8 males and 4 females) were fixed across the injured vertebra (group B). All patients were followed up for 6-36 months (mean 11.5 months). The vertebral body height, endplate angle and neurofunction were compared between the two groups before surgery, a week after surgery and at the end of the follow-up period.

RESULTSThere was no statistically significant difference in vertebral body height,endplate angle and neurofunction before operation between group A and B (P > 0.05). Vertebral body height and endplate angle improved in both groups a week after operation and at the end of the follow-up period as compared with those before operation (P < 0.05), and the efficacy in group B was significantly better than that in group A (P < 0.05). There was no significant difference in neurofunction between the two groups (P > 0.05).

CONCLUSIONThe fixation method through the injured vertebra had a better reduction effect, more stable fixation, and a better long-term effect on vertebral morphology than that across the injured vertebra in the treatment of thoracolumbar vertebral fractures.

Adult ; Female ; Humans ; Lumbar Vertebrae ; injuries ; pathology ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Spinal Fractures ; surgery ; Thoracic Vertebrae ; injuries ; pathology ; surgery

OBJECTIVETo evaluate the biomechanical properties of geneX cements for use in vertebroplasty in a calf osteoporotic vertebral compression fracture model.

METHODSThirty vertebral bodies (T(9)-L(4)) were harvested from 4 fresh calf spines. The bone mineral density was measured with dual-energy radiographic absorption. Osteoporotic vertebral model was induced in each vertebra using decalcifying chemical agents, and was then compressed to determine their initial strength and stiffness before injecting the cement. Thirty vertebral bodies were divided randomly into geneX(®) cement group, CSC group, and PMMA group. The fractures were repaired using a transpedicular injection of cements and re-compressed to measure posttreatment strength and stiffness.

RESULTSThe normal mean BMD of the calf vertebra was 1.425∓0.072 g/cm(2), which was reduced significantly to 1.074∓0.065 g/cm(2) after decalcification. The mean injected volume was similar between geneX(®) (4.5∓0.7 ml), CSC (4.3∓0.8 ml) and PMMA (3.8∓0.4 ml) groups. The vertebral strength was restored after the treatment to 1198∓529 N in geneX(®) group, 1212∓430 N in CSC group and 1672∓704 N in PMMA group. All the cements produced significantly greater strength than the initial strength (P<0.05). The augmented strength in geneX(®) and CSC groups were similar (P>0.05), but both were significantly less than that in PMMA group (P<0.05). The stiffness in geneX(®), CSC, and PMMA groups was 233∓130, 242∓191, and 323∓145 N/mm, respectively, showing no significant difference between them (P>0.05). No significant difference was found in the augmented stiffness among the 3 cements (P>0.05).

CONCLUSIONgeneX(®) cement is a useful alternative to PMMA in vertebroplasty for osteoporotic vertebral compression fractures, but further study is needed to evaluate its biosorption in vivo.

Animals ; Biomechanical Phenomena ; Bone Cements ; therapeutic use ; Cattle ; Disease Models, Animal ; Fractures, Compression ; etiology ; surgery ; Lumbar Vertebrae ; injuries ; Osteoporosis ; complications ; pathology ; Thoracic Vertebrae ; injuries ; Vertebroplasty

OBJECTIVESTo evaluate and analyze the role of posterior ligament complex (PLC) in determining therapeutic principle for traumatic thoracic-lumbar fracture.

METHODSFrom August 2005 to May 2008, 60 patients (38 male, 22 female) who suffered from the traumatic thoracic-lumbar fracture were carried out posterior operations. According to the Magerl traumatic thoracic-lumbar fracture classification system, these cases were classified to subtype A, B and C. The average age was 34 years (21 - 65 years). Magnetic resonance imaging (MRI) scan, which including both T1/T2 weight and fat-stir sequence, as well as the MRI negative film reading technique were used to evaluate the state of PLC. Furthermore, related physical or neurological examinations (such as severe skin bruising and sinking, broadening spinous process gap and tenderness, spinal cord or nerve root injury) and another X-ray or CT reconstruction films were taken to evaluate the the state of PLC synthetically. Above-mentioned results were compared with the final exploration results during operation and some parameters were analyzed.

RESULTSThe sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), misdiagnosis rate and rate of missed diagnosis of these sixty patients were 85.3%, 80.8%, 83.3%, 85.3%, 80.8%, 19.2%, 14.7% respectively. After 13 cases of thoracic-lumbar fracture-dislocation were eliminated, the sensitivity, specificity, accuracy, PPV, NPV, misdiagnosis rate and rate of missed diagnosis of remaining 47 cases were 81.0%, 80.8%, 80.9%, 77.3%, 84.0%, 19.2%, 19.0% respectively. There were 5 cases with MRI negative results before operation but positive results during operation. Contrarily, 5 cases with MRI positive results before operation but negative results during operation occurred.

CONCLUSIONSMRI is a main means for evaluating the state of PLC. Although the MRI fat-stir sequence as well as the MRI negative film reading technique are adopted, the state of PLC can not be estimated exactly before operation (especially for those unfracture dislocation cases). In order to estimate the state of PLC exactly, the related local physical examination and image technology as well as the location of the abnormal image signal in MRI film and time of injury must be analyzed synthetically.

Adult ; Aged ; Female ; Humans ; Ligaments ; pathology ; Lumbar Vertebrae ; injuries ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Spinal Fractures ; pathology ; surgery ; Thoracic Vertebrae ; injuries ; Young Adult

Humans ; Lumbar Vertebrae ; diagnostic imaging ; pathology ; physiopathology ; surgery ; Postoperative Complications ; etiology ; Soft Tissue Injuries ; etiology ; Spondylolisthesis ; complications ; diagnostic imaging ; physiopathology ; surgery ; Tomography, X-Ray Computed

OBJECTIVETo study the correlation between intrusion of nucleus gelatinosus into vertebral body and low back pain after thoracolumbar fractures.

METHODSOne hundred and two patients who were treated in Peking university third hospital from January 2005 to September 2007 were evaluated retrospectively and included into this study. They were followed up for an average of 18 months and complete data were kept. Fifty-four patients were treated operatively and forty-eight patients were treated conservatively. VAS questionnaire was applied to evaluate the low back pain. Spearman Correlation Coefficients module and Wilcoxon 2-Sample Test module of SAS software were used to analyze the relation between intrusion of nucleus gelatinosus, different treatments, kyphotic Cobb angles and VAS.

RESULTSThere were strong correlations between intrusion of nucleus gelatinosus and VAS in both operative group, P < 0.01 and non-operative group, P < 0.01; there were poor correlations between different treatments and VAS in both intrusion group, P > 0.05 and non-intrusion group, P > 0.05; and there were also poor correlations between Cobb angles and VAS, gamma = 0.2584, P > 0.05.

CONCLUSIONThere is correlation between the intrusion of nucleus gelatinosus into vertebral body and the low back pain after thoracolumbar fractures.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Back Pain ; etiology ; Female ; Humans ; Intervertebral Disc ; pathology ; Lumbar Vertebrae ; injuries ; Male ; Middle Aged ; Spinal Fractures ; complications ; pathology ; Thoracic Vertebrae ; injuries ; Young Adult

Adult ; Cauda Equina ; injuries ; physiopathology ; surgery ; Female ; Follow-Up Studies ; Humans ; Intervertebral Disc Displacement ; complications ; physiopathology ; surgery ; Lumbar Vertebrae ; pathology ; surgery ; Male ; Middle Aged ; Recovery of Function

OBJECTIVETo observe degenerative intervertebral disc and to examine innervation of degenerative discs in the rabbit anular-injury model.

METHODSTwo different magnitudes of anular injury at 5 mm depth were performed by 11 blade or 16 gauge needle at the L3-L4 or L5-L6 discs in New Zealand white rabbits (n=48, 2.5-3.0 kg). Disc degeneration was evaluated by radiographic, MRI and histological examination at different time points after surgery. To identify nerve ingrowth into disc, two general markers PGP 9.5 and GAP 43, for nerve fibers were examined by immunohistochemistry.

RESULTSignificant decreases in disc height and signal intensity in magnetic resonance imaging were observed in 11 blade group and 16 G puncture group (P<0.01). 16 G puncture group induced slower and more progressive disc degeneration companed with the stab group and control group. At the 12-week time point, nucleus pulposus tissues were extruded and scar tissues formed outside the disc. In stab discs, nerve ingrowth was scattered on the surface of injury site and in the deeper part of the scar tissues, more than 1 mm from the surface. However, in punctured discs, PGP 9.5 and GAP 43-immunoreative fibers were only observed in the outmost part of the scar tissues and superficial area. More nerve fibers were observed in stab group.

CONCLUSIONInnervation may act as a source of discogenic pain which is associated with intervertebral disc degeneration caused by disc anular injury.

Animals ; GAP-43 Protein ; metabolism ; Intervertebral Disc ; injuries ; innervation ; pathology ; Intervertebral Disc Degeneration ; diagnosis ; diagnostic imaging ; etiology ; Low Back Pain ; etiology ; Lumbar Vertebrae ; Male ; Nerve Fibers ; pathology ; Rabbits ; Radiography ; Random Allocation ; Ubiquitin Thiolesterase ; metabolism