Excessive swelling of nerve roots : Important factor for recurring sciatica after lumbar surgery.

OBJECTIVE: The aim of the study was to investigate the occurrence of unexpectedly swollen nerve roots and to investigate the relationship between nerve root edema and recurrent radicular pain. METHODS: During the period from August 2010 to August 2015, a total of 462 patients with degenerative lumbar disease underwent surgery in this study group. Magnetic resonance imaging (MRI) was used to evaluate the details of the nerve root. Of the patients with recurring radiating pain 13 met the inclusion criteria of the study group and 24 patients without any complications volunteered as the control group. The visual analog scale (VAS), Oswestry Disability Index (ODI), and medical outcomes study item short form health survey (SF-36) were used to evaluate the clinical outcomes. RESULTS: The preoperative diameter of the nerve root showed no significant difference between the two groups (P = 0.28). The postoperative nerve diameter of the study group was larger than that of the control group (P < 0.01). The initial operation improved the symptoms and the VAS was significantly decreased (P < 0.01). After recurrence of the neuralgia, the VAS score significantly increased (P < 0.01). The pain of the study group improved to the same level as that of the control group 4 weeks after subsequent surgery (P = 0.47), while the quality of life was still lower than that of the control group (P < 0.05). The scores collected 3 months after surgery showed that the clinical outcomes were not different between the two groups (P > 0.05). CONCLUSION: In surgery for degenerative lumbar disease accompanied by nerve root edema, excessive nerve root swelling is an important factor for recurrent radiating pain. With a properly carried out intervention in the re-exploration, the recurrent symptoms can be gradually relieved.

Therapeutic effects analysis of percutaneous kyphoplasty for osteoporotic vertebral compression fractures: A multicentre study.

BACKGROUND: Percutaneous kyphoplasty (PKP), a minimally invasive treatment, has been widely used for osteoporotic vertebral compression fractures (OVCFs). OBJECTIVE: To retrospectively analyse the therapeutic effects of PKP using a series of key techniques in a multicentre study. METHODS: From May 2000 to December 2016, PKP was performed using a series of key techniques (puncture, reduction, and perfusion techniques) for the treatment of 4532 OVCF patients. The pain visual analog scale (VAS) and the Oswestry Disability Index (ODI) questionnaire prior to the operation, at postoperative Day 2, and at the last follow-up were analysed by paired t-test analysis. The leakage of bone cement was evaluated by postoperative radiography and/or computed tomography. Four-year survival was calculated at the last follow-up. RESULTS: The average follow-up was 63 months (1-116 months). The VAS score decreased from 8.9 (preoperative) to 2.3 (2 days postoperative) to 1.9 (last follow-up). The ODI score of the patients decreased from 86.7 (preoperative) to 31.6 (2 days postoperative) to 25.3 (last follow-up). Both VAS score and ODI score improved significantly. The bone cement leakage rate was 3.5%, with no clinical symptoms. The 4-year survival rate was 77.5%. CONCLUSION: This study suggests that PKP with key techniques would be an effective technique to treat OVCF with less risk and better therapeutic effect. Such diagnostic methods and surgical techniques lead to the development and progress of treatment for OVCF.The translational potential of this article: PKP with key techniques would be an effective technique to treat and lead to the development and progress of treatment for OVCF.

Treatment of Crowe Type-IV Hip Dysplasia Using Cementless Total Hip Arthroplasty and Double Chevron Subtrochanteric Shortening Osteotomy: A 5- to 10-Year Follow-Up Study.

BACKGROUND: The purpose of this study was to evaluate the functional and radiographic results of patients with Crowe type-IV hip dysplasia treated by cementless total hip arthroplasty and double chevron subtrochanteric osteotomy. METHODS: From January 2000 to February 2006, cementless total hip arthroplasty with a double chevron subtrochanteric shortening osteotomy was performed on 18 patients (22 hips) with Crowe type-IV dysplasia. The acetabular cup was placed in the position of the anatomic hip center, and subtrochanteric femoral shortening osteotomy was performed with the use of a double chevron design. The clinical and radiographic outcomes were reviewed with a mean follow-up of 6.5 years (5-10 years). RESULTS: The mean amount of femoral subtrochanteric shortening was 38 mm (25-60 mm). All osteotomy sites were healed by 3-6 months without complications. The mean Harris Hip Score improved significantly from 47 points (35-65 points) preoperatively to 88 points (75-97 points) at the final follow-up. The Trendelenburg sign was corrected from a positive preoperative status to a negative postoperative status in 12 of 22 hips. No acetabular and femoral components have loosened or required revision during the period of follow-up. CONCLUSION: Cementless total hip arthroplasty using double chevron subtrochanteric osteotomy allowed for restoration of anatomic hip center with safely functional limb lengthening, achieved correction of preoperative limp, and good functional and radiographic outcomes for 22 Crowe type-IV dislocation hips at the time of the 5- to 10-year follow-up.

Three-Year Follow-up of Conservative Treatments of Shoulder Osteoarthritis in Older Patients.

Little is known about the mid-term results of nonsurgical treatment for shoulder osteoarthritis (OA), especially in a Chinese population. This study sought to determine the efficacy of nonsurgical management in older patients with shoulder OA. A total of 129 conservatively treated unilateral shoulder OA patients who were older than 65 years were evaluated prospectively at the initial office visit and then subsequently at 3, 6, 12, 18, 24, and 36 months later. During the 36-month follow-up period, all patients could receive conventional therapy, such as nonsteroidal anti-inflammatory medication, corticosteroid injection, sodium hyaluronate, and education, at the discretion of treating physicians. Some patients received physiotherapy, rehabilitation training, and a shoulder strap to improve the range of motion and muscular strength training from a physical therapist. Parameters measured included comparative effectiveness of each therapeutic method, visual analog scale (VAS), Simple Shoulder Test (SST), and Short Form (36) Health Survey (SF-36) scores. At 3-year follow-up, most patients had a significant increase from their pretreatment values in pain, self-assessed shoulder function, mental health, and 5 of 8 SF-36 domains. The study showed a decline in SST and VAS at 6 and 12 months after an initial ascent at 3 months, and then it was rescued and continued at 3-year follow-up. Combined therapy could improve symptoms significantly. This study suggests that a conservative approach may be more appropriate and can produce satisfactory mid-term outcomes in selected cases. The findings of this study suggest that conservative treatments should be extended for longer than 12 months before the decision regarding shoulder arthroplasty is made. [Orthopedics. 2016; 39(4):e634-e641.].

Restoration of the spinopelvic sagittal balance in isthmic spondylolisthesis: posterior lumbar interbody fusion may be better than posterolateral fusion.

BACKGROUND CONTEXT: More and more orthopedic surgeons recognize the importance of the sagittal balance of the spine. PURPOSE: To analyze the pre- and postoperative sagittal and deformity parameters of low-grade isthmic spondylolisthesis and evaluate the effect of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) on spinopelvic sagittal balance. STUDY DESIGN: Nonrandomized controlled prospective study with a historical control. PATIENT SAMPLE: A total of 99 patients with low-grade L5-S1 isthmic spondylolisthesis were treated surgically; 36 patients (mean age, 60.2±5.2 years) received the PLF operation, and 63 patients (mean age, 57.1±6.9 years) chose the PLIF operation. The healthy control group was composed of 60 volunteers (mean age, 44.5±8.4 years). OUTCOME MEASURES: The pre- and postoperative spinopelvic and deformity parameters. METHODS: All patients had radiographs that allowed measurement of spinopelvic parameters before and after the operation. All the spinopelvic and deformity parameters were measured. Two radiologists measured the parameters with the Cobb method. RESULTS: All of the preoperative spinopelvic parameters showed no difference between the PLIF and PLF groups in this study (p>.05). In both of the operation groups, the preoperative pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), and L5 incidence (L5I) were significantly higher than in the control group (p<.01); the height of the intervertebral disc (HOD) was significantly lower than the controls. There were no significant differences in PT among PLIF, PLF, and control groups after the operation (p>.05). LL increased in the PLIF group and decreased in the PLF group. The slip degree (SD) and L5I were restored significantly in both groups. The HOD of the PLIF group increased 5.04 mm, the postoperative HOD of the PLF group had no significant change. In both PLIF and PLF groups, the correction of SD was correlated with the change of LL (r=-0.398, p=.007; r=0.365, p=.022). The restoration of HOD in the PLIF group correlated with the change of LL (r=0.334, p=.011). No significant differences could be found between the short-term clinical outcomes of the PLF and PLIF. CONCLUSION: Either PLF or PLIF would lead a great change in spinopelvic parameters and deformity parameters. The decrease of PT may be an important role for the short-term surgical outcome. The PLIF could increase the LL and form a more reasonable sagittal alignment. From the point of the sagittal spinopelvic balance, the PLIF may be better than the PLF for patients with isthmic spondylolisthesis.

Changes in autophagy proteins in a rat model of spinal cord injury.

OBJECTIVE: Autophagy is involved in several neurodegenerative diseases and recently its role in acute brain injury has won increasing interest. Spinal cord injuries (SCIs) often lead to permanent neurological deficit. Therefore, in this study, we examined the pro?les of autophagy-linked proteins (MAP-LC3) after SCI to investigate whether the expression of autophagy contributes to neurological deficit after SCI. METHODS: Adult female Sprague-Dawley rats were used and randomly divided into control and SCI groups. All the rates received laminectomy at T8-T10 level. Those in the SCI group received additional exposure of the dorsal surface of the spinal cord, followed by a weight- drop injury. Thereafter we investigated the expression levels of MAP-LC3, beclin-1, Cathepsin D and the beclin-1-binding protein bcl-2 by western blot analysis at 12 h, 24 h, 3 d, 7 d, 21 d and 28 d. One-way ANOVA with Tukey post hoc test was used to compare data between groups. RESULTS: We observed significant increase in the level of LC3 (LC3-II/LC3-I) at 3 d and 7 d after SCI when compared with the sham group. While the level of beclin-1 and ratio of beclin-1/bcl-2 was found to have increased from 12 h to 24 h after injury. Cathepsin D expression was also elevated at 7 d (P<0.01). CONCLUSION: Based on the above mentioned data, we proposed that autophagy plays a role in the manifestation of cell injury following SCI.

Laminoplasty versus conservative treatment for acute cervical spinal cord injury caused by ossification of the posterior longitudinal ligament after minor trauma.

BACKGROUND CONTEXT: No reports to date have accurately evaluated the management for acute spinal cord injury (SCI) caused by ossification of the posterior longitudinal ligament (OPLL) after minor trauma. PURPOSE: To assess whether outcomes of laminoplasty is better than conservative treatment. STUDY DESIGN/SETTING: A retrospective study. PATIENT SAMPLE: Thirty-one patients underwent surgery (L group) and 29 patients underwent conservative treatment (C group). OUTCOME MEASURES: Disability, muscle strength, sensation, and general health status. METHODS: Patients were managed according to routine clinical practice and the results between groups were compared. Clinical and radiographic outcomes were assessed at admission, discharge, 6 months and at the final visit. Causes for trauma, duration of hospital stay, and complication were also evaluated. RESULTS: Causes for trauma included falling, traffic accidents and sports. Mixed and segmental types were the most frequent cause of OPLL resulting into SCI. Duration of hospital stay and complications were less in the L group. Motor and sensory scores increased in the L group at discharge (p<.05) and at 6 months (p<.05), and maintained thereafter (p>.05); scores improved significantly in the C group at 6 months (p<.05), with a slight deterioration with time (p>.05); scores in the L group were higher than in the C group at each time point after surgery (p<.05). Bodily pain and mental health in SF-36 improved at discharge in the L group (p<.05); all scores improved at 6 months in both the groups (p<.05), with better improvements in the L group (p<.05). The canal diameter increased and occupation ratio decreased in the L group (p<.05), and maintained thereafter (p<.05); a slight increase of occupation ratio was observed in the C group (p>.05). Lordotic angle and range of motion were maintained in both the groups, with no significance between groups (p>.05). High-signal intensity decreased at 6 months (p<.05) in the L group; no significant change was found in the C group during the follow-up (p>.05); Significant difference was detected between the groups at 6 months and at the final visit (p<.05). CONCLUSIONS: Most of the OPLL patients displayed as incomplete SCI after minor trauma. Although spontaneous improvement of SCI without surgery is often observed, laminoplasty has more satisfactory outcomes, prevents late compression of cord, and reduces perioperative complications, although with no significant benefit in cervical alignment and range of motion.

Influence of the posterior lumbar interbody fusion on the sagittal spino-pelvic parameters in isthmic L5-S1 spondylolisthesis.

STUDY DESIGN: Prospective study of the sagittal spino-pelvic parameters and deformity parameters in low-grade isthmic spondylolisthesis preoperation and postoperation. OBJECTIVE: To better understand how the surgery influences sagittal spino-pelvic alignment in low-grade spondylolisthesis. SUMMARY OF BACKGROUND DATA: Over the past decade, the importance of the sagittal spino-pelvic parameters was recognized. However, the postoperative change of sagittal balance parameters in low-grade spondylolisthesis was still unclear. METHODS: Forty-nine patients (mean age, 53.2±7.2 y) with low-grade L5-S1 isthmic spondylolisthesis and 60 normal volunteers (mean age, 44.5±8.4 y) were included in the study. Each subject had a radiograph that allowed measurement of sagittal spino-pelvic parameters before and after surgery. The follow-up duration was at least 2 years. Sagittal spino-pelvic parameters and deformity parameters were measured for comparison. RESULTS: Pelvic incidence, pelvic tilt (PT), sacral slope, lumbar lordosis (LL), lumbar 5 incidence, and lumbosacral angle of normal volunteers were smaller than those of spondylolisthesis patients. All of the parameters changed significantly after the posterior lumbar interbody fusion. Postoperative PT reduced by 4.9 degrees, which had no significant difference compared with the control group (P=0.601). The changes of slip degree and height of the intervertebral disk revealed correlation with the increase of LL (r=-0.483, P=0.003; r=0.365, P=0.010). CONCLUSION: The improvement of PT may play an important role in the reconstruction of the sagittal alignment and therapeutic outcome. The restoration of the slip degree and height of the intervertebral disk would increase the LL with a wedged cage. To get a better LL, the size and geometry of the cage was recommended to be evaluated before surgical treatment.

Cementless total hip arthroplasty with a double chevron subtrochanteric shortening osteotomy in patients with Crowe type-IV hip dysplasia.

The authors describe a modified double chevron subtrochanteric shortening osteotomy combined with cementless total hip arthroplasty for Crowe type-IV hip dysplasia. Shortening the femur allows to relax the shortened musculature. This operation was performed in 18 patients (22 hips) between January 2000 and February 2006. The mean follow-up period was 5.6 years (range: 3 to 8 years). The mean amount of femoral subtrochanteric shortening was 38 mm (range: 25 to 60 mm). The mean Harris hip score improved from 47 (range: 35 to 65) preoperatively to 88 points (range: 75 to 97) at final follow-up. The Trendelenburg sign was corrected from positive to negative in 12 of 22 hips. No acetabular or femoral components loosened or required revision during the follow-up period. All osteotomy sites healed in 3 to 6 months without complications. Cementless total hip arthroplasty using the modified double chevron subtrochanteric osteotomy provided good short- to midterm results in all 22 Crowe type-IV hip dislocations. Moreover, it restored the anatomic hip center and the limb length, which contributed to correction of the preoperative limp.

A clinical morphologic study of the C2 pedicle and isthmus.

PURPOSE: This anatomic, radiographic study investigated locational differences in the C2 pedicle and isthmus [pediculoisthmic component (PIC)] and characterized its narrowest section for clinical application in posterior C2 screw fixation. METHODS: Structures surrounding the transverse foramina of 30 dry C2s and 10 C3s were compared morphologically. Spinal CT scans of 32 Chinese adults were subjected to volume rendering and multiplanar reconstruction to identify the narrowest C2 PIC, and correlative parameters were measured and analyzed. RESULTS: Inferior C2 and C3 structures were morphologically similar. In superior view, the C2 superior facets lay on the transverse foramen and the upper portion between superior and inferior facets was flat (average mediolateral angle, 11.1° ± 2.4°). In inferior view, the posteroinferomedial portion of the C2 transverse foramen displayed a partially tubular structure (average mediolateral angle of projection, 42.6° ± 4.9°). Average height and width were 11.6 and 6.9 mm. The inner medullary cavity was elliptical and the middle site of endosteal diameter was 3.3 ± 1.9 mm. Medial internal cortical bone was significantly thicker than lateral bone (P < 0.01). CONCLUSIONS: The PIC is located between superior and inferior C2 facets. The superior flat area is the isthmus and the inferomedial area connecting the inferior facet and vertebral body is the pedicle. The pedicle is partially tubular and projects posteromedially to the transverse foramen. The narrowest PIC section is the narrowest point of the C2 pedicle. Considering its thin lateral cortical bone, medial and superior pedicle screw placement and preoperative CT reconstruction are recommended.

Pain reduction following vertebroplasty and kyphoplasty.

PURPOSE: To evaluate the clinical efficacy, especially the pain reduction, of vertebroplasty and balloon kyphoplasty in the treatment of osteoporotic vertebral compression fractures (OVCFs). METHODS: Eighty-six patients with OVCFs were treated with vertebroplasty or balloon kyphoplasty. All patients were followed up for seven-36 months. Visual analog scale (VAS), vertebral height, and local kyphotic angle were evaluated at pre-operation, postoperation, and final follow-up. RESULTS: The VAS pain score decreased significantly after surgery in both kyphoplasty and vertebroplasty groups (p < 0.001), and the improvement of VAS score had no significant difference between the two groups (p = 0.826). There was a significant difference in the improvement of vertebral height (p < 0.001) and local kyphotic angle (p < 0.001) between the two groups. Improvement of VAS score had no correlation with improvement of vertebral height (vertebroplasty: r = -0.029, p = 0.869; kyphoplasty: r = 0.175, p = 0.219) or local kyphotic angle (vertebroplasty: r = 0.159, p = 0.361; kyphoplasty: r = 0.144, p = 0.312) in either group. CONCLUSION: Vertebroplasty and kyphoplasty are effective procedures for the reduction of pain in OVCFs, and they have the same efficient effect on pain reduction. Correction of vertebral height and local kyphosis may have minimal effect on pain reduction.

[SOX9 enhanced chondrogenic differentiation potential of human umbilical cord mesenchymal stem cells through cellular aggregation].

OBJECTIVE: To explore the effects of transcription factor SOX9 on chondrogenic differentiation potential of human umbilical cord mesenchymal stem cells (hUC-MSCs). METHODS: hUC-MSCs were harvested from human umbilical cord and their phenotypic characteristics identified by flow cytometry. To confirm their multipotency, hUC-MSCs were induced to differentiate toward adiposity and osteogenesis. After transfection with the packaging lentivirus vectors containing SOX9 in vitro, the expression of green fluorescent protein (GFP) and the efficiency of transfection were detected by fluorescence microscopy. Their cellular proliferation capacity was detected by thiazolyl blue tetrazolium bromide (MTT) assay.hUC-MSCs modified with SOX9 were seeded into monolayer and cultured for 21 days in a defined, serum-free medium supplemented with transforming growth factor (TGF)-ß1. The untransduced cells or those transduced with GFP served as the controls. Morphologic changes of hUC-MSCs were observed daily and their chondrogenic differentiation was evaluated by reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunofluorescent staining. And the accumulation of sulfated glycosaminoglycans was detected by Alcian blue staining. Meanwhile, the expressions of collagen I, X and cell adhesion molecule N-cadherin were assayed. RESULTS: The hUC-MSCs isolated from human umbilical cord stromas exhibited fibroblastic morphology and they were positive for CD29 (95.9%), CD44 (96.5%), CD90 (98.9%), CD105 (94.3%) and negative for hematopoietic stem cells surface markers CD34 (3.0%) and CD45 (2.6%). At Day 21, hUC-MSCs differentiated toward adiposity and osteogenesis. Both oil red O and alkaline phosphatase stains were intensely positive and it confirmed the multilineage potential of hUC-MSCs. An intense expression of GFP was observed under flourescence microscope and the transfection efficiency of cells with Lenti-GFP-SOX9 or Lenti-GFP was more than 90% respectively. SOX9 gene was over-expressed in hUC-MSCs at 48 h post-transduction. The proliferation of hUC-MSCs had no significant effect after the transfection of lentivirus vectors (P > 0.05). In vitro high-density monolayer culture of these SOX9-transfected hUC-MSCs demonstrated that spontaneous cell aggregation appeared at Day 14 of culturing and subsequently generated large cartilage nodules. However there was no phenomenon of cell aggregation occurring in the cells transducted by Lenti-GFP or untransduced vectors. The expressions of collagen II and Aggrecan were higher in SOX9 transducted cells than those in the controls. Alcian blue staining also showed abundant accumulation of sulfated glycosaminoglycans in the SOX9-induced cartilage nodules. The expression of collagen I had no difference in all groups and collagen X was inhibited in SOX9 transduced cells. N-cadherin was strongly up-regulated by SOX9 and might result in cellular aggregation and formation of large cartilage nodules. CONCLUSION: SOX9 may enhance the chondrogenic differentiation potential of human umbilical cord mesenchymal stem cells through cellular aggregation.

Acute effect of Ghrelin on ischemia/reperfusion injury in the rat spinal cord.

Ghrelin, a 28-amino acid peptide, is mainly secreted by the stomach. Ghrelin has been shown to have neuroprotective effects. However, whether ghrelin protects the spinal cord from ischemia/reperfusion (I/R) injury is unknown. To investigate this, 60 rats were randomly divided into three different groups: the sham group (n = 20), the vehicle group (n = 20), and the Ghrelin group (100 µg/kg, n = 20). Rats were sacrificed 12, 24, 48 and 72 h after ischemia. After the evaluation of neurologic function (48 h), the spinal cords were immediately removed for the determination of myeloperoxidase (MPO) activity (12-72 h). Apoptosis was quantitatively measured using the terminal transferase UTP nick end-labeling (TUNEL) method (24 h). The expression of bax and bcl-2 were evaluated by Western blot analysis (1 h), and GHSR-1a mRNA expression was detected using reverse transcriptase polymerase chain reaction (24 h). The neurological motor function was evaluated by 'Tarlov's score'. The neurologic outcomes in the ghrelin-group were significantly better than those in the vehicle group (p < 0.05). Serum tumor necrosis factor (TNF-α) levels were assessed in the peripheral venous blood. Ghrelin decreased the serum TNF-α levels and ameliorated the down regulation of spinal cord MPO activity. The expression of ghrelin receptors (GHSR-1a) in the rat spinal cord was decreased by I/R injury and increased by ghrelin. Ghrelin reduced the TUNEL-positive rate. Greater bcl-2, HSP27, HSP70, and attenuated bax expression were observed in the ghrelin-treated rats. Our results suggest that ghrelin administration may inhibit spinal I/R injury. Moreover, the improvement of neurologic function in rats was increased after the ghrelin treatment.

Comparison of kyphoplasty and vertebroplasty for treatment of painful osteoporotic vertebral compression fractures: twelve-month follow-up in a prospective nonrandomized comparative study.

STUDY DESIGN: A prospective nonrandomized comparative study. OBJECTIVE: To compare the efficacy and safety of kyphoplasty and vertebroplasty for treatment of painful osteoporotic vertebral compression fractures (VCFs) with respect to pain, functional outcome, radiomorphology, cement leakage, and incidence of new adjacent vertebral fracture. SUMMARY OF BACKGROUND DATA: Kyphoplasty and vertebroplasty have become common treatments for painful osteoporotic VCFs. Although the benefits of either kyphoplasty or vertebroplasty compared with conservative treatment have been frequently discussed, few clinical studies are available that directly compare the 2 procedures. METHODS: Ninety-six patients with painful osteoporotic VCFs less than 4 weeks old were included and nonrandomly assigned to undergo kyphoplasty or vertebroplasty treatment. Clinical outcomes were assessed using the visual analog scale and the Oswestry Disability Index. Plain radiographs were analyzed to quantify spinal deformity correction (vertebral body height and kyphotic angle), and evaluate cement leakage and new adjacent vertebral fractures. The follow-up time was 12 months. RESULTS: The baseline clinical and radiological characteristics of both groups were comparable. There were no significant differences between the 2 groups with regard to improvement in pain and functional scores at all postoperative intervals. Vertebral height restoration and kyphotic angle reduction were achieved in both groups, but the correction of spinal deformity was more significant in the kyphoplasty group. Asymptomatic cement leakage occurred in 9.1% and 34.6% of treated vertebrae for the kyphoplasty and vertebroplasty groups, respectively. Three adjacent fractures in the kyphoplasty group and 2 in the vertebroplasty group were identified during the follow-up time, and no major adverse events were observed. CONCLUSIONS: Kyphoplasty and vertebroplasty demonstrated similar good clinical outcomes during the 12-month follow-up. Kyphoplasty offers a higher degree of spinal deformity correction and results in less cement leakage than vertebroplasty. The benefits of these relative merits need to be ascertained in future long-term studies.

Protective effects of two constituents of Chinese herbs on spinal motor neurons from embryonic rats with hypoxia injury.

Neuroprotective agents are becoming significant tools in the repair of central nervous system injuries. In this study, we determined whether ginkgolides (Gin, extract of GinkgoBiloba) and Acanthopanax senticosus saponins (ASS, flavonoids extracted from Acanthopanax herbal preparations) have protective effects on rat spinal cords exposed to anoxia and we explored the mechanisms that underlie the protective effects. Spinal motor neurons (SMNs) from rat spinal cords were obtained and divided into five groups with 10 wells in each group. In control group, SMNs suffered no injury under normal oxygen; in hypoxia- inducible (HI) group, SMNs suffered injury from hypoxia; in Gin group, 37.5µg/ml Gin were used before 24 hrs of hypoxia; in ASS group, 50µg/ml ASS were used before 24 hrs of hypoxia;in glial cell-lined derived neurotrophic factor (GDNF) group, 0.1µg/ml GDNF were used before 24 hrs of hypoxia. Changes in morphology, neuron viability, and lactate dehydrogenase (LDH) release were observed. In addition, the expression of HIF-1α induced by hypoxia was measured. The neuronal viability in the Gin, ASS, and GDNF pretreated groups was higher than that in the HI group (P<0.05). The viability in the Gin group was better than that in the ASS group (P<0.05), but there was no significant difference between the ASS and GDNF groups (P>0.05). The quantity of LDH released in the three pretreated groups was lower than that in the HI group (P<0.05). The expression of HIF-1α in the HI group was greater than that in the control group (P<0.05), and the expression in the three pretreated groups was greater than that in the HI and the control groups (P<0.05). Our results indicate that Gin and ASS which was not as effective as Gin, but its effects were similar to those of GNDF could all enhance the viability of SMNs and have protective effects on hypoxic neurons.

Evaluation of an injectable silk fibroin enhanced calcium phosphate cement loaded with human recombinant bone morphogenetic protein-2 in ovine lumbar interbody fusion.

The objective of this study was to investigate the efficacy of an injectable calcium phosphate cement/silk fibroin/human recombinant bone morphogenetic protein-2 composite (CPC/SF/rhBMP-2) in an ovine interbody fusion model. Twenty-four mature sheep underwent anterior lumbar interbody fusion at the levels of L1/2, L3/4, and L5/6 with random implantation of CPC/SF, CPC/rhBMP-2, CPC/SF/rhBMP-2, or autogenous iliac bone. After the sheep were sacrificed, the fusion segments were evaluated by manual palpation, CT scan, undestructive biomechanical testing, undecalcified histology, and histomorphology. The fusion rates of CPC/SF/rhBMP-2 were 55.56% and 77.78% at 6 and 12 months, respectively. The fusion was superior to all the biomaterial grafts in stiffness, and reached the same stiffness as the autograft at 12 months. The new bone formation was less than autograft at 6 months, but similar with that at 12 months. However, the ceramic residue volume of CPC/SF/rhBMP-2 was significantly decreased compared with CPC/SF and CPC/rhBMP-2 at both times. The results indicated that CPC/SF/rhBMP-2 composite had excellent osteoconduction and osteoinduction, and balanced degradation and osteogenesis.

Post-traumatic osteoporotic vertebral osteonecrosis treated using balloon kyphoplasty.

Nineteen patients with post-traumatic osteoporotic vertebral osteonecrosis were treated using percutaneous balloon kyphoplasty. The anterior and middle vertebral heights, as well as the kyphotic angle, were measured using a standing lateral radiograph before surgery, 2 days after surgery and at the final follow-up. At the same time points, a visual analog scale and the Oswestry Disability Index were used to evaluate pain status and functional activity, respectively. The mean follow-up was 24.7 months (range: 7-36 months). Statistically significant improvements were observed between the preoperative and postoperative assessments for each evaluated measure (p<0.05). There were no statistically significant differences between the postoperative and final follow-up assessments (p>0.05). Asymptomatic cement leakage into the intervertebral disc occurred in three patients. This study suggests that balloon kyphoplasty is a safe and effective procedure for treating this disease entity.