Is Complete Correction of Cervical Sagittal Malalignment Necessary During 4-Level Anterior Cervical Discectomy and Fusion Surgery in Patients With Kyphosis?

STUDY DESIGN: Retrospective analysis. OBJECTIVE: We investigated whether complete correction of cervical sagittal malalignment is necessary during 4-level anterior cervical discectomy and fusion (ACDF) in patients with kyphosis. METHODS: This retrospective study included 84 patients who underwent 4-level ACDF surgery at a university hospital between January 2010 and December 2015. Based on the degree of cervical lordosis correction, patients were categorized into the following groups: mild (0-10°), moderate (10-20°), and complete correction (>20°). The clinical outcomes, radiological parameters, and functional outcomes were analyzed. RESULTS: We observed no significant intergroup differences in the baseline characteristics. The cervical sagittal vertical axis (CSVA) correction loss at the final follow-up was lesser in the mild- and moderate- than in the complete-correction group. The spinocranial angle (SCA) and T1 slope (T1 S) were significantly higher in the moderate- and complete-correction groups than in the mild-correction group, 3 days postoperatively. The cervical proximal junctional kyphosis (CPJK), adjacent segment degeneration (ASD), and ASD following CPJK rates were higher in the complete-correction group. We observed no significant intergroup differences in postoperative complications; however, 5 patients showed internal fixation failure in the complete-correction group; 4 of these patients required reoperation. No significant intergroup difference was observed in the Japanese Orthopedic Association and neck disability index scores at any time point. CONCLUSIONS: A mild-to-moderate correction of cervical lordosis is superior to complete correction in patients with kyphosis who undergo 4-level ACDF because this approach is associated with lesser axial stress and CSVA correction loss.

Polydatin induces apoptosis and autophagy via STAT3 signaling in human osteosarcoma MG-63 cells.

Polydatin, a natural product, is detected in many daily diets, such as grape juices and peanut. Autophagy regulation is recognized as a new potential strategy for cancer therapy, and previous studies demonstrated that polydatin showed remarkable anti-cancer ability. Nevertheless, the capability of polydatin to induce autophagy and its role in anti-osteosarcoma remains obscure. In this study, we investigated the anticancer effect of polydatin on human osteosarcoma cell line MG-63 and its underlying mechanism. Our results indicated that polydatin significantly inhibited proliferation of MG-63 cells in a dose- and time-dependent manner, and increased their apoptosis and autophagic flux. Further experiments showed that polydatin reduced the expression and phosphorylation (Y705) level of STAT3 (Signal transducer and activator of transcription 3), increased the expression of autophagy-related genes (Atg12, Atg14, BECN1, PIC3K3), and therewith triggered autophagic cell death in MG-63 cells. Of note, the cytotoxicity effect of polydatin was rescued by co-treatment with Colivelin (STAT3 activator), suggesting the dependency of MG-63 cells on STAT3 for survival in this process. Moreover, polydatin-triggered autophagy and apoptosis were remarkably reduced following exposure to autophagy inhibitor 3-methyladenine, while cell viability was increased. In conclusion, these data demonstrated that polydatin induced MG-63 cell death through inducing apoptosis, and autophagy which was mediated via the STAT3 signaling. Therefore, polydatin might be a potential clinical drug in the remedy of osteosarcoma.

miR-149-5p inhibits cell growth by regulating TWEAK/Fn14/PI3K/AKT pathway and predicts favorable survival in human osteosarcoma.

MicroRNAs (miRNAs) as small non-coding RNAs act as either tumor suppressors or oncogenes in human cancers, of which miR-149-5p (miR-149) is involved in tumor growth and metastasis, but its role and molecular mechanisms underlying osteosarcoma growth are poorly understood. The correlation of miR-149 expression with clinicopathological characteristics and prognosis in patients with sarcoma was analyzed by The Cancer Genome Atlas (TCGA) RNA-sequencing data. Osteosarcoma cell growth affected by miR-149 was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assays. As a result, we found that the expression level of miR-149 was markedly downregulated in human sarcoma samples and were negatively associated with tumor size, acting as an independent prognostic factor for overall survival of the sarcoma patients. Restoration of miR-149 expression suppressed osteosarcoma cell growth, while its knockdown reversed these effects. Furthermore, we identified TNFRSF12A (TNF receptor superfamily member 12A), also called fibroblast growth factor-inducible 14 (Fn14) as a direct target of miR-149, and TNFRSF12A and its ligand TNFSF12 (TNF superfamily member 12), also called tumor necrosis factor-related weak inducer of apoptosis (TWEAK), were both negatively correlated with miR-149 expression in sarcoma samples. Knockdown of TNFRSF12A suppressed cell growth, but its overexpression weakened the antiproliferative effects of miR-149 via the PI3K/AKT (AKT serine/threonine kinase) signaling pathway. Altogether, our findings show that miR-149 functions as a tumor suppressor in osteosarcoma via inhibition of the TWEAK-Fn14 axis and represents a potential therapeutic target in patients with osteosarcoma.

Effect of Asymmetric Tension on Biomechanics and Metabolism of Vertebral Epiphyseal Plate in a Rodent Model of Scoliosis.

OBJECTIVE: To investigate the effect of asymmetric tension on idiopathic scoliosis (IS) and to understand its pathogenic mechanism. METHODS: The rodent model of scoliosis was established using Sprague-Dawley rats with left rib-tethering from T6 to T12 , tail and shoulder amputation, and high-cage feeding. Vertebrae epiphyseal cartilage plates were harvested from the convex and concave sides. To analyze differences on the convex and concave sides, finite element analysis was carried out to determine the mechanical stress. Protein expression on epiphyseal cartilage was evaluated by western blot. Micro-CT was taken to evaluate the bone quality of vertebral on both sides. RESULTS: Scoliosis curves presented in X-ray radiographs of the rats. Finite element analysis was carried out on the axial and transverse tension of the spine. Stresses of the convex side were -170.14, -373.18, and -3832.32 MPa (X, Y, and Z axis, respectively), while the concave side showed stresses of 361.99, 605.55, and 3661.95 MPa. Collagen type II, collagen type X, Sox 9, RunX2, VEGF, and aggrecan were expressed significantly more on the convex side (P < 0.05). There was asymmetric expression of protein on the epiphyseal cartilage plate at molecular level. Compared with the convex side, the concave side had significantly lower value in the BV/TV and Tb.N, but higher value in the Tb.Sp (P < 0.05). There was asymmetry of bone quality in micro-architecture. CONCLUSIONS: In this study, asymmetric tension contributed to asymmetry in protein expression and bone quality on vertebral epiphyseal plates, ultimately resulting in asymmetry of anatomy. In addition, asymmetry of anatomy aggravated asymmetric tension. It is the first study to show that there is an asymmetrical vicious circle in IS.

The Effect of Estradiol on the Growth Plate Chondrocytes of Limb and Spine from Postnatal Mice in vitro: The Role of Estrogen-Receptor and Estradiol Concentration.

Objectives: Skeletal development is a complex process. Little is known about the different response of limb or spine growth plate chondrocytes (LGP or SGP) to the estrogen level and the role of estrogen receptor (ER) during postnatal stage. Methods: LGP and SGP chondrocytes were isolated from 50 one-week mice and treated with different concentrations of 17ß-estradiol. Cell viability was measured by cell counting kit-8 (CCK-8). The expression of collagen II and X were evaluated by real-time PCR and Western blotting. Then, the response of LGP or SGP chondrocyte after with or without estradiol and specific ER antagonists to block the effect of ERs were also measured by Western blotting and immunofluorescence. Results: Estradiol promoted the chondrogensis of the chondrocytes in vitro and achieved the maximal expression of type II collagen at the dose of 10-7 M. Additionally, the regulatory effect of estradiol on the chondrogenesis can be mainly relied on ERα. The LGP chondrocytes were more sensitive to the estradiol treatment than SGP in the expression of type II collagen. Conclusions: Estrogen at a pharmacological concentration (10-7 M) could stimulate the maximal production of type II collagen in the growth plate chondrocytes in vitro, which exerts its activity mainly through ERα in the chondrogenesis. Furthermore, the LGP chondrocytes were more sensitive to the estradiol treatment than SGP in the chondrogenesis.

Risk Factors for Dysphagia After Single-Level Anterior Cervical Decompression with Arthroplasty or Fusion: A Prospective Study Comparing 2 Zero-Profile Implants.

OBJECTIVE: To determine any differences in self-reported dysphagia in patients treated with single-level anterior cervical decompression with different zero-profile implants (arthroplasty vs. arthrodesis) and identify risk factors for postoperative dysphagia. METHODS: A total of 112 patients with 1-level cervical degenerative disc disease were included in the prospective study. The dysphagia conditions and radiologic results were assessed using Bazar dysphagia scoring system, the Swallowing Quality of Life scores, cervical alignment (CA), segmental angle, and prevertebral soft tissues swelling (PSTS). All these parameters were compared before and after surgery in the respective group, which were also compared between the 2 groups. Correlations between the confounding factors and postoperative dysphagia were analyzed. RESULTS: No significant differences existed in preoperative or initially postoperative dysphagia rate and scores between the 2 groups (P > 0.05). However, the dysphagia rate and scores of cervical disc arthroplasty was better than those of fusion at postoperative day 7. Heavy smoker, PSTS change (≥5 mm), or CA change (≥5 degrees) was prone to have postoperative dysphagia. CONCLUSIONS: Postoperative dysphagia remains a common incidence, despite advances in instrumentation technologies. However, cervical disc arthroplasty is superior to anterior cervical discectomy and fusion in ameliorating the symptom of dysphagia in the early postoperative term. Heavy smoker, PSTS change (≥5 mm), and CA change (≥5 degrees) were important predictors of postoperative dysphagia.

Comparison of 2 Zero-Profile Implants in the Treatment of Single-Level Cervical Spondylotic Myelopathy: A Preliminary Clinical Study of Cervical Disc Arthroplasty versus Fusion.

OBJECTIVES: Cervical disc arthroplasty (CDA) with Discover prosthesis or anterior cervical discectomy and fusion (ACDF) with Zero-P cage has been widely used in the treatment of cervical spondylotic myelopathy (CSM). However, little is known about the comparison of the 2 zero-profile implants in the treatment of single-level CSM. The aim was to compare the clinical outcomes and radiographic parameters of CDA with Discover prosthesis and ACDF with Zero-P cage for the treatment of single-level CSM. METHODS: A total of 128 consecutive patients who underwent 1-level CDA with Discover prosthesis or ACDF with Zero-P cage for single-level CSM between September 2009 and December 2012 were included in this study. Clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) score and Neck Disability Index (NDI). For radiographic assessment, the overall sagittal alignment (OSA), functional spinal unit (FSU) angle, and range of motion (ROM) at the index and adjacent levels were measured before and after surgery. Additionally, the complications were also recorded. RESULTS: Both treatments significantly improved all clinical parameters (P < 0.05), without statistically relevant differences between the 2 groups. The OSA and FSU angle increased significantly in both groups (P <0.05). Compared with Zero-P group, ROMs at the index levels were well maintained in the Discover group (P < 0.05). However, there were no statistical differences in the ROMs of adjacent levels between the 2 groups (P > 0.05). Besides, no significant differences existed in dysphagia, subsidence, or adjacent disc degeneration between the 2 groups (P > 0.05). However, significant differences occurred in prosthesis migration in CDA group. CONCLUSIONS: The results of this study showed that clinical outcomes and radiographic parameters were satisfactory and comparable with the 2 techniques. However, more attention to prosthesis migration of artificial cervical disc should be paid in the postoperative early-term follow-up.

Comparison of a Stand-Alone Anchored Spacer Versus Plate-Cage Construct in the Treatment of Two Noncontiguous Levels of Cervical Spondylosis: A Preliminary Investigation.

OBJECTIVE: The application of stand-alone anchored spacer (SAAS) in anterior cervical discectomy and fusion (ACDF) has been proven to be safe and effective to treat cervical spondylosis. Skip-level ACDF with SAAS, fusing only the involved levels without anterior plates, may be the optimal treatment. The aim of the study was to compare the clinical outcomes, radiologic results of SAAS, and plate-cage construct in the treatment of 2 noncontiguous levels of cervical spondylosis. METHODS: A total of 65 patients with 2 noncontiguous levels of cervical spondylosis were included in the retrospective review of prospective collected data. The clinical and radiologic outcomes were assessed with the Japanese Orthopaedic Association score, Neck Disability Index, cervical alignment, and range of motion and disc height of intermediate segment, respectively. All the aforementioned parameters were compared before and after surgery in the respective group, which also were compared between the 2 groups. Complications also were recorded, and correlations between the surgical outcome and various factors were analyzed. RESULTS: No significant differences existed in clinical results between the 2 groups (P > 0.05). In addition, no statistical significance was observed in fusion rate, cervical alignment, and range of motion and disc height of intermediate segment, dysphagia, and hoarseness (P > 0.05). Preoperative Japanese Orthopaedic Association score and high-intensity signal in T2-weighted images were important predictors for surgical outcome. CONCLUSIONS: Skip-level ACDF with SAAS is a safe and effective treatment of 2 noncontiguous levels of cervical spondylosis without obvious contraindications, which can keep the IS intact, and have a low impact on the IS.

Application of a stand-alone anchored spacer in noncontiguous anterior cervical arthrodesis with radiologic analysis of the intermediate segment.

The purpose of this study was to describe the clinical features of noncontiguous cervical degenerative disc disease (cDDD), investigate the efficacy and complications of a stand-alone anchored spacer (SAAS) for patients with noncontiguous cDDD, and present radiologic analysis of the intermediate segment (IS) after skip-level fusion. Nineteen consecutive patients with noncontiguous cDDD who underwent skip-level anterior cervical discectomy and fusion (ACDF) with SAAS from January 2010 to December 2012 were enrolled in this study. Clinical outcomes were assessed preoperatively and at 24 months postoperatively using the Japanese Orthopaedic Association score, Neck Disability Index, and Visual Analog Scale. Overall cervical alignment (OCA) of the cervical spine, and the range of motion (ROM), intervertebral disc height (IDH), disc signal intensity and disc protrusion of IS were measured and compared before and after surgery. Clinical outcomes significantly improved compared to preoperative scores. The OCA was corrected and maintained at 24 months postoperatively compared with preoperative values (p<0.05). There were no significant differences in the ROM and IDH of the IS at each follow-up (p>0.05). However, decreased signal intensity on T2-weighted MRI was evidenced in three mobile IS at final follow-up (20.0%). Skip-level ACDF with SAAS may be an efficacious option for the treatment of noncontiguous cDDD.

Comparison of plate-cage construct and stand-alone anchored spacer in the surgical treatment of three-level cervical spondylotic myelopathy: a preliminary clinical study.

BACKGROUND CONTEXT: Although stand-alone cages were advocated to be superior to plate-cage construct (PCC) because of comparable clinical outcomes and fewer plate-related complications, cage dislocation and subsidence were frequently mentioned in multilevel fusion. There are some concerns about whether these issues can be effectively prevented in multilevel anterior cervical discectomy and fusion (ACDF) by stand-alone anchored spacer (SAAS). PURPOSE: The aim was to compare clinical outcomes, radiologic parameters, and complications of PCC and SAAS in the treatment of three-level cervical spondylotic myelopathy (CSM). STUDY DESIGN/SETTING: This was a retrospective comparative study. PATIENT SAMPLE: A total of 38 consecutive patients with three-level CSM (ACDF with PCC, 20 patients; ACDF with SAAS, 18 patients) were reviewed. OUTCOME MEASURES: Clinical outcomes were assessed using Japanese Orthopaedic Association and Neck Disability Index. The radiologic evaluations included cervical alignment (CA), segmental angle (SA), postoperative curvature loss (PCL), and incidence of subsidence. METHODS: All the aforementioned parameters were compared before and after surgery between two groups. Besides, the aforementioned results were also compared between the two groups. The complications were also recorded. RESULTS: The mean follow-up period was 30.3 months. No significant differences were observed in clinical outcomes between the two groups (p>.05). Additionally, no significant differences existed in fusion rate between the two groups. There were significant differences in PCL of SA and CA and correction of SA between the two groups (p<.05). Besides, the incidence of subsidence (9 of 54 levels, 16.7%) was recorded in the SAAS group, and the potential of SAAS to reduce the incidence of postoperative dysphagia was not proven. No other complications were observed in this study. CONCLUSIONS: In the surgical treatment of three-level CSM, PCC is superior to SAAS in correction and maintenance of SA and avoiding cage subsidence, although the technique of ACDF with SAAS yielded encouraging clinical outcomes and high fusion rate.

Lever reduction using polyaxial screw and rod fixation system for the treatment of degenerative lumbar spondylolisthesis with spinal stenosis: technique and clinical outcome.

BACKGROUND: The management for degenerative lumbar spondylolisthesis with spinal stenosis remains controversial. Reduction of lumbar spondylolisthesis has been performed via numerous techniques. Most of them need extra reduction assembly. METHODS: In this retrospective analysis, 27 patients of degenerative lumbar spondylolisthesis with spinal stenosis underwent reduction using polyaxial screw and rod constructs and posterolateral fusion. The average age at the time of surgery was 53 ± 3.23 years. The outcome measures consisted of a radiographic assessment of deformity and fusion rate and a clinical assessment of perioperative improvement in low back pain and function. Preoperative and postoperative radiographic evaluation included the percent slip, slip angle, and the lumbar lordosis between L1 and the sacrum measured using the Cobb method. Before surgery and at the final follow-up, the Oswestry Disability Index (ODI) and the visual pain analog scale (VPAS) between 0 (no pain) and 10 (maximal pain) were quantified. RESULTS: The average follow-up period more than 5 years was available. The mean operative time was 90.19 ± 14.51 min, and the mean blood loss during surgery was 152.59 ± 45.71 ml. The mean length of incision was 4.83 ± 0.63 cm. The average percent slippage and the mean slip angle were, respectively, 19.8 ± 4.49% and 9.69 ± 3.79° before surgery, 5.09 ± 3.40% and 6.39 ± 3.16° after surgery, and 5.67 ± 3.92% and 7.21 ± 3.05° at the last follow-up. The average lumbar lordosis was 36.88 ± 2.64° before surgery, 41.96 ± 1.64° after surgery, and 40.27 ± 1.19° at the final follow-up. No neurologic deficit occurred. Solid fusion was achieved for all cases. Compared with the outcome preoperation, the data improved from 6.56 ± 1.40 to 2.48 ± 1.16 for VPAS pain scores and from 32.22 ± 3.57 to 10.93 ± 4.93 for the ODI at the final follow-up. CONCLUSIONS: Lever slip reduction maneuver techniques using polyaxial screw and rod fixation system was simple and practicable. The treatment outcomes showed satisfactory radiographic characteristics and clinical results. The length of the incision was relatively small with a low intraoperative blood loss and short operation time.

Kinetic magnetic resonance imaging analysis of spinal degeneration: a systematic review.

OBJECTIVE: To evaluate the clinical use of kinetic magnetic resonance imaging (kMRI) in spinal degenerative diseases. METHODS: A systematic search of PubMed, EMBASE and ISI databases for articles that had been published between January 1978 and February 2013 concerning patients who had undergone kMRI for spinal problems was performed. All selected patients had undergone kMRI in neutral, flexion, and extension weight-bearing positions. Evaluation of cervical and lumbar degeneration by kMRI was analyzed. kMRI showed significant reduction of mobility in cervical segments of patients with severe disc degeneration; in addition, it was more severely reduced in patients with severe cord compression than in those without it. In the cervical spine, it was found that although disc height, translational motion, and angular variation were significantly affected at the level of disc herniation, no significant changes were apparent in adjacent segments. kMRI also showed that lumbar degeneration is closely associated with disc degeneration, facet joint osteoarthritis and the pathological characteristics of the interspinous ligaments, ligamentum flavum and paraspinal muscles. RESULTS: Eleven articles (4162 patients) fulfilled the inclusion criteria and were reviewed. It was found that kMRI is more specific and sensitive than conventional MRI regarding relating patients' symptoms to objective findings on imaging that demonstrate pathology and biomechanics. In the kinetic position, kMRI improves detection of disc herniation by 5.78%-19.46% and thus provides a new means of studying the biomechanical mechanism(s) in degenerative spines. CONCLUSION: Kinetic MRI is effective for diagnosing, evaluating, and managing degenerative disease within the spine; however, it still has some limitations.

Estrogen receptor expression in lumbar intervertebral disc of the elderly: gender- and degeneration degree-related variations.

OBJECTIVES: Sexual dimorphism does occur in intervertebral disc (IVD) degeneration. The involvement of estrogen on IVD health has been well reported in recent years. The estrogen receptors (ER) are the main mediators of estrogen action. ER might play specific roles in the sexual variations of the IVD degeneration. METHODS: Thirty-six elderly patients with lumbar disc degeneration were selected and graded using Pfirrmann's system based on MRI images. Differences of ERα and ERß immunoreactivity staining in nucleus pulposus of each sex and degeneration degree were recorded and compared. RESULTS: Both cytoplasmic and nuclear staining of ERα and ERß immunoreactivity were observed in the nucleus pulposus cells. ERα and ERß expression significantly decreased along with the aggravation of IVD degeneration both in males and females. Expression of ERα and ERß protein in nucleus pulposus of males was significantly higher than that of females. CONCLUSIONS: Gender-specific expression of ER might play a part in sexual dimorphism of IVD degeneration. Gender and degeneration condition differences should be taken into account when the effects of estrogen on IVD metabolism are studied further.

Effective reinnervation of the quadriceps femoris by spinal ventral root cross-anastomosis in rats.

PURPOSE: To study the effective recovery of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. METHODS: End-to-end anastomosis was performed between the left L(1) and L(3) ventral roots using autogenous nerve graft, and the right L(1) and L(3) roots were left intact. In control animals, the left L(3) ventral root was cut and shortened, and anastomosis was not performed. Six months postoperatively, the movement of low extremities was detected by electrophysiological examination, hindlimb locomotion and basso, beattie and bresnahan (BBB) scoring at one, three, seven, 14, 21 and 28 days after SCI. Fluorescence retrograde tracing with TRUE BLUE (TB) and HE staining were performed to observe the nerve regeneration. RESULTS: Six months after surgery, the anastomotic nerve was smooth and not atrophic. The amplitudes of action potential were 7.63 ± 1.86 mV and 6.0 ± 1.92 mV respectively before and after the spinal cord hemisection. The contraction of left quadriceps femoris was induced by a single stimulation of the anastomotic nerve. The locomotion of left hindlimb was partially restored after spinal cord hemisection while creeping and climbing. In addition, there was significant difference in the BBB score at one, three and seven days after SCI. TB retrograde tracing and neurophysiologic observation indicated efficient reinnervation of the quadriceps femoris. CONCLUSION: The cross-anastomosis between spinal ventral root can partially reconstruct the function of quadriceps femoris following SCI and may have clinical implication for the treatment of human SCI.

Effective reinnervation of the quadriceps femoris by spinal ventral root cross-anastomosis in rats / Reinervação efetiva do quadríceps femoral pela anastomose cruzada via raiz espinhal ventral em ratos

PURPOSE: To study the effective recovery of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. METHODS: End-to-end anastomosis was performed between the left L1 and L3 ventral roots using autogenous nerve graft ,and the right L1 and L3 roots were left intact. In control animals, the left L3 ventral root was cut and shortened, and anastomosis was not performed. Six months postoperatively, the movement of low extremities was detected by electrophysiological examination, hindlimb locomotion and basso, beattie and bresnahan (BBB) scoring at one, three, seven, 14, 21 and 28 days after SCI. Fluorescence retrograde tracing with TRUE BLUE (TB) and HE staining were performed to observe the nerve regeneration. RESULTS: Six months after surgery, the anastomotic nerve was smooth and not atrophic. The amplitudes of action potential were 7.63±1.86 mV and 6.0±1.92 mV respectively before and after the spinal cord hemisection. The contraction of left quadriceps femoris was induced by a single stimulation of the anastomotic nerve. The locomotion of left hindlimb was partially restored after spinal cord hemisection while creeping and climbing. In addition, there was significant difference in the BBB score at one, three and seven days after SCI. TB retrograde tracing and neurophysiologic observation indicated efficient reinnervation of the quadriceps femoris. CONCLUSION: The cross-anastomosis between spinal ventral root can partially reconstruct the function of quadriceps femoris following SCI and may have clinical implication for the treatment of human SCI.

OBJETIVO: Investigar a recuperação efetiva do músculo quadríceps femoral pela anastomose cruzada via raiz espinhal ventral em ratos. MÉTODOS: Anastomose término-terminal foi realizada entre as raízes ventrais L1 e L3 à esquerda usando enxerto autógeno de nervo e, à direita, as raízes L1 e L3 foram mantidas intactas. Nos animais controles, à esquerda, a raiz ventral de L3 foi cortada e encurtada sem realização de anastomose. Após seis meses, o movimento das extremidades posteriores foi estudado por exame eletrofisiológico, e pelo escore de basso, beattie e bresnahan (BBB) com um, três, sete, 14, 21 e 28 dias após SCI. Fluorescência retrograde feita com TRUE BLUE (TB) e coloração com HE foram realizadas para observar a regeneração do nervo. RESULTADOS: Seis meses após a cirurgia, a anastomose do nervo estava lisa e sem atrofia. As amplitudes dos potenciais de ação foram 7,63±1,86 mV e 6,0±1,92 mV respectivamente antes e após a hemisecção da medula espinhal. A contração do músculo quadríceps femoral foi induzida por um único estímulo do nervo anastomosado. A locomoção do membro posterior esquerdo foi parcialmente restaurada após hemisecção da medula espinhal ao rastejar e escalar. Ademais, houve diferença significante no escore BBB nos dias um, três e sete após SCI. O traçado da TB retrógrada e a observação neurofisiológica indicaram reinervação eficiente do quadríceps femoral. CONCLUSÃO: A anastomose cruzada entre as raízes espinhais ventrais podem reconstruir parcialmente a função do quadríceps femoral após SCI e pode ter implicação clínica para o tratamento da SCI.

Posterior unilateral pedicle subtraction osteotomy of hemivertebra for correction of the adolescent congenital spinal deformity.

BACKGROUND CONTEXT: The treatment of adolescent congenital deformity (late-diagnosed congenital deformity) is still unknown. The best candidates for hemivertebra excision are young patients, typically between 4 and 6 years of age. Partial excision may be feasible for older children. PURPOSE: The purpose of this study was to assess the effect of unilateral pedicle subtraction osteotomy of hemivertebra for correction of the adolescent congenital spinal deformity. STUDY DESIGN: Retrospective analysis. PATIENT SAMPLE: Twelve patients with adolescent congenital deformity who underwent posterior unilateral pedicle subtraction osteotomy and correction were evaluated. Mean age at the time of surgery was 17 years. OUTCOME MEASURES: The charts, standing full-length posteroanterior and lateral view radiographs, and functional measures were reviewed. METHODS: For evaluation of surgical effectiveness, comparative analysis of the parameters of the total main curve, the segmental curve, the compensatory cranial and caudal curves, the segmental kyphosis, and the trunk shift before and after operation and at the most recent follow-up was done. RESULTS: The mean follow-up period was 40.5 months. Mean Cobb angles of the total main curve and the segmental curve were, respectively, 47.5° and 43.8° before surgery, 23.7° and 16.5° after surgery, and 22.6° and 17° at the last follow-up. The angle of segmental kyphosis was 11.8° before surgery, 6.2° after surgery, and 7.8° (range, -30° to 26°) at the final follow-up. The mean final global lordosis was within the normal range. No neurologic deficit occurred. Solid fusion was achieved for all cases. CONCLUSIONS: Unilateral pedicle subtraction osteotomy with instrumentation from a posterior-only approach is indicated in older teenagers for an adolescent congenital spinal deformity. Compared with hemivertebra excision, corrective surgery with hemivertebra osteotomy has a lower intraoperative blood loss and shorter operation time.

Surgical treatment of scoliosis associated with Marfan syndrome by using posterior-only instrumentation.

Surgical treatment of scoliosis associated with Marfan syndrome poses a challenge to spine surgeons. This retrospective study was undertaken to determine whether posterior-only surgery with instrumented fixation and fusion addresses the correction of scoliosis and maintains curve correction. Twelve consecutive patients with Marfan syndrome were treated between 2002 and 2007 for scoliosis by posterior segmental instrumentation using pedicle screws or hybrid thoracic-hook and lumbar-screw constructs. Their preoperative Cobb angle averaged 66 ± 10° (range: 55-90°). The average operation time was 252 ± 36 min (range: 200-300 min) and the average blood loss was 690 ± 117 ml (range: 550-920 ml). No significant complications were found. All the patients were followed for a minimum of 2 years (range: 2.4-6.8 years). The average Cobb angle was corrected to 23 ± 8° (range: 13-35°) immediately after surgery and 28 ± 9° (range: 14-43°) with a correction rate of 58 ± 13% at final follow-up. The results indicate that posterior-only surgery with instrumented fixation and fusion is effective and safe for the treatment of scoliosis in selected patients with Marfan syndrome.