Chang Lu

Surgical treatment of cervical kyphosis

Cervical kyphosis is an uncommon but potentially debilitating and challenging condition. We reviewed the etiology, presentation, clinical and radiological evaluation, and treatment of cervical kyphosis. Based on the current controversy as to the ideal mode of surgical management, we paid particular attention to the available surgical strategies. There are three approaches for cervical kyphosis: the anterior, posterior or combined procedures. The principal indication for the posterior strategy is a flexible kyphosis or kyphosis caused by ankylosing spondylitis. The main point of debate is between the choice of the anterior or the combined strategy. The two strategies were compared with regard to clinical outcome, correction of deformity, rate of fusion, complications, revision surgery, and mortality. The combined strategy appears to result in a greater degree of correction than the anterior-alone strategy, and it is more likely to improve the cervical alignment to achieve a lordosis. However, the procedure carries a higher rate of postoperative neurological deterioration, complications, revision surgery, and mortality. Although the anterior-alone strategy achieves a smaller reduction of cervical kyphosis, it has a lower rate of postoperative neurological deterioration, complications, revision surgery, and mortality. We recommend that the surgical treatment of cervical kyphosis should be planned on an individual basis. A multicenter, prospective, randomized controlled study would be necessary to determine the ideal mode of treatment for complex cervical kyphosis.

Mucormycosis spondylodiscitis after lumbar disc puncture

Vertebral osteomyelitis due to mucormycosis is a rare but fulminant and fatal disease. Only one case has been reported in literature, with postmortem diagnosis. The present paper reports a female case of mucormycosis spondylodiscitis and vertebral osteomyelitis after lumbar disc puncture and radio frequency nucleoplasty. She subsequently underwent two surgical debridements, continuous local irrigation and drainage, together with local and systemic Amphotericin B treatments. The infection was controlled 4 months after the second debridement; however, there was no improvement in the neurological function at the most recent follow-up, 16 months after the surgery. The experience of this patient, though a single case, supports early recognition, surgical debridement, systemic and local antifungal treatment, closed irrigation and drainage as the keys to successful treatment.

LncRNA-RP11-296A18.3/miR-138/HIF1A Pathway Regulates the Proliferation ECM Synthesis of Human Nucleus Pulposus Cells (HNPCs)

During the process of Intervertebral disc degeneration (IDD), nucleus pulposus apoptosis increases, extracellular matrix (ECM) alters and/or degrades, abnormal proliferation of cells forms cell clusters, and the expression of various inflammatory factors increases. Thus, regulation of human nucleus pulposus cell (HNPC) proliferation and ECM synthesis present promising strategies for IDD treatment. Accumulating evidence indicates that non‐coding RNAs are involved in various cellular processes, including cell proliferation, differentiation, apoptosis, and metastasis. High expression of long non‐coding RNA (lncRNA) RP11‐296A18.3, as well as a low expression of miR‐138 during the IDD process has been reported; yet their functional roles in HNPC proliferation and ECM synthesis still remain unclear. MTT and BrdU assays showed that knockdown of RP11‐296A18.3 inhibited the proliferation of HNPC. The ECM marker, MMP‐13 and Collagen I expressions were also reduced. Bioinformatics target prediction, qPCR, and luciferase assays identified LncRNA‐RP11‐296A18.3 interacted with miR‐138. Moreover, RP11‐296A18.3 regulates HNPC proliferation and ECM synthesis through miR‐138. As the target gene of miR‐138, hypoxia‐inducible factor 1‐alpha (HIF1A) was closely associated with cell proliferation which was also regulated by RP11‐296A18.3 via miR‐138. Immunochemistry and qPCR results showed that miR‐138 expression was inversely correlated to RP11‐296A18.3 and HIF1A in IDD tissues, respectively; RP11‐296A18.3 was positively correlated to HIF1A. We revealed that RP11‐296A18.3 promote HIF1A expression through sponging miR‐138, thus to promote HNPC proliferation and ECM synthesis. Targeting RP11‐296A18.3 to rescue miR‐138 expression in HNPCs and IDD tissues presents a promising strategy for IDD improvement. J. Cell. Biochem. 118: 4862–4871, 2017.

Surgical management for thoracic spinal tuberculosis posterior only versus anterior video-assisted thoracoscopic surgery.

Study Design A comparable retrospective study. Object To compare the clinical outcomes of surgical treatment by posterior only and anterior video-assisted thoracoscopic surgery for thoracic spinal tuberculosis (TSTB). Method 145 patients with TSTB treated by two different surgical procedures in our institution from June 2001 to June 2014 were studied. All cases were retrospectively analyzed and divided into two groups according to the given treatments: 75 cases (32F/43M) in group A performed single-stage posterior debridement, transforaminal thoracic interbody fusion and instrumentation, and 70 cases (30F/40M) in group B underwent anterior video-assisted thoracoscopic surgery (VATS). Clinical and radiographic results in the two groups were analyzed and compared. Results Patients in group A and B were followed up for an average of 4.6±1.8, 4.4±1.2 years, respectively. There was no statistically significant difference between groups in terms of the operation time, blood loss, bony fusion, neurological recovery and the correction angle of kyphotic deformity (P>0.05). Fewer pulmonary complications were observed in group A. Good clinical outcomes were achieved in both groups. Conclusions Both the anterior VATS and posterior approaches can effectively treat thoracic tuberculosis. Nevertheless, the posterior approach procedure obtained less morbidity and complications than the other.

Surgical treatment of large abdominally involved primary dumbbell tumor in the lumbar region.

Study Design: This was a retrospective clinical study. Objective: The aim of this study was to assess the efficacy of a combined anterior and posterior approach, or single-stage posterior extensive approach for resection of large abdominally involved dumbbell tumor in the lumbar region. Background: Resection of the large spinal-retroperitoneal involved dumbbell tumor is particularly controversial and challenging because of unique exposure requirements. Methods: From June 2006 to October 2011, 18 consecutive patients suffering from large dumbbell tumors in the lumbar region were involved. In the initial 8 patients, a combined posterior and anterior surgical approach was applied. The remaining 10 patients were surgically treated with a single posterior extensive approach to excise both the intraspinal and intra-abdominal tumors. Reconstruction with bone or mesh grafts was also performed simultaneously in 3 of the 10 patients in this group. Results: The perioperative period was uneventful for 7 of 8 patients who underwent combined surgery. However, 1 patient encountered right nephrectomy because of a ruptured renal vein and refractory bleeding during anterior tumor exposure. Histopathology revealed the presence of schwannoma (n=4), neurofibroma (n=3), and neuroblastoma (n=1). With the mean of 52 months of follow-up, metastasis occurred in 1 patient with neuroblastoma. In the 10 patients with only the posterior approach, histopathology demonstrated schwannoma (n=5), neurofibroma (n=3), small round cell mesenchymal tumor (n=1), and benign fibrous histiocytoma (n=1). No recurrence was detected at the mean follow-up of 24 months. Conclusions: The posterior extensive approach is safe and effective to remove the large abdominally involved dumbbell tumors, and also facilitates simultaneously reconstruction of the vertebral body, as compared with the combined posterior and anterior approach.

Thoracolumbar fracture dislocations treated by posterior reduction, interbody fusion and segmental instrumentation.

Background: Literature describing the application of modern segmental instrumentation to thoracic and lumbar fracture dislocation injuries is limited and the ideal surgical strategy for this severe trauma remains controversial. The purpose of this article was to investigate the feasibility and efficacy of single-stage posterior reduction with segmental instrumentation and interbody fusion to treat this type of injury. Materials and Methods: A retrospective review of 30 patients who had sustained fracture dislocation of the spine and underwent single stage posterior surgery between January 2007 and December 2011 was performed. All the patients underwent single stage posterior pedicle screw fixation, decompression and interbody fusion. Demographic data, medical records and radiographic images were reviewed thoroughly. Results: Ten females and 20 males with a mean age of 39.5 years were included in this study. Based on the AO classification, 13 cases were Type B1, 4 cases were B2, 4 were C1, 6 were C2 and 3 cases were C3. The average time of the surgical procedure was 220 min and the average blood loss was 550 mL. All of the patients were followed up for at least 2 years, with an average of 38 months. The mean preoperative kyphosis was 14.4° and reduced to -1.1° postoperatively. At the final followup, the mean kyphosis was 0.2°. The loss of correction was small (1.3°) with no significant difference compared to postoperative kyphotic angle (P = 0.069). Twenty seven patients (90%) achieved definitive bone fusion on X-ray or computed tomography imaging within 1 year followup. The other three patients were suspected possible pseudarthrosis. They remained asymptomatic without hardware failure or local pain at the last followup. Conclusion: Single stage posterior reduction using segmental pedicle screw instrumentation, combined with decompression and interbody fusion for the treatment of thoracic or lumbar fracture-dislocations is a safe, less traumatic and reliable technique. This procedure can achieve effective reduction, sagittal angle correction and solid fusion.

Pedicle screw implantation in the thoracic and lumbar spine of 1-4-year-old children: evaluating the safety and accuracy by a computer tomography follow-up.

Study Design: This was a retrospective clinical study. Objective: To evaluate the safety and accuracy of pedicle screw placement in very young children and to observe its influence on vertebral and spinal canal growth. Summary of Background Data: Although widely used, it is not known if pedicle screw fixation is safe and effective in very young children. Methods: Sixteen children, with an average age of 34 months, had received pedicle screw fixation from January 2003 to January 2010. Candidates for surgery were those patients who had hemivertebra deformity (11 patients), eosinophilic granuloma disease with spinal cord compression, and neurological deficit (2 patients), or spinal tuberculosis accompanied with kyphotic deformity (3 patients). The location of involved vertebrae was between T2 and L5. A total of 74 pedicle screws were implanted using a modified free-hand technique. The safety and accuracy of this method, and the influence on vertebral growth, was evaluated using postoperative x-ray and computer tomography scans. Result: The average follow-up was 30.6 months. No patient had any neurological or radicular symptoms related to the placement of pedicle screws. Postoperative computer tomography scans demonstrated a malposition of 5 of the 74 pedicle screws (6.8%). Two screws breached the anterolateral cortical bone of the vertebral body. One screw breached the lateral cortical bone of the pedicle, 1 passed through the anterior vertebral margin by 3 threads, and a third was so laterally placed that it entered into disk space. There was no vessel, visceral complications, or any other adverse effects resulting from these misplacements. No screw was placed so medially that injured the spinal cord. No retardation of vertebral growth was observed in 7 patients who were followed up for at least 3 and up to 7 years. Conclusions: The results indicate that in very young children, pedicle screws can be safely implanted using a modified free-hand implantation technique.

Posterior Distraction and Instrumentation Cannot Always Reduce Displaced and Rotated Posterosuperior Fracture Fragments in Thoracolumbar Burst Fracture.

Study Design: A retrospective clinical study. Objective: To determine the imaging features that can be used to predict failure of reduction of a retropulsed fracture fragment by posterior ligamentotaxis in thoracolumbar burst fractures. Summary of Background Data: Posterior instrumentation and distraction with ligamentotaxis has been successfully used to shift retropulsed fragments anteriorly in thoracolumbar burst fractures. However, posterior longitudinal ligament rupture can lead to treatment failure. The exact preoperative radiographical parameters associated with failure of reduction remain unknown. Materials and Methods: A total of 85 patients who suffered from thoracolumbar burst fractures with significant retropulsion of fragments into the spinal canal, as confirmed by preoperative computed tomography and followed by postoperative computed tomography, were retrospectively analyzed. Seventy-three patients (85.9%) in whom the fragments were reduced by ligamentotaxis were included in the reduced group. In 12 patients (14.1%), the fracture fragment in the spinal canal was not reduced, and these patients were included in the nonreduced group. Neurologic status was classified according to the scoring system of the American Spinal Injury Association (ASIA). The displaced distance and rotation angle of the fracture fragment were measured at the fractured segment. Results: Preoperatively,the average displacement distances into the spinal canal of rotated posterosuperior fragments was 0.53 cm in the reduced group and 0.94 cm in the nonreduced group (P=0.002). The average rotation angles of the fracture fragments were 43.2 degrees in the reduced group and 61.7 degrees in the nonreduced group (P=0.012). “Double cortical surfaces” of the fragment were observed in the nonreduced patients. Neurological function was evaluated and recorded at the 2-year follow-up examination. There was no significant difference in the ASIA recovery grade between the 2 groups (P=0.668). Conclusions: Displaced and rotated posterosuperior fracture fragments in thoracolumbar burst fracture cannot always be reduced by posterior ligamentotaxis. The 2 criteria for treatment failure that were most consistently present in our series were a displacement distance greater than 0.85 cm and a rotation angle greater than 55 degrees.

Modified Pedicle Subtraction Osteotomy as a Salvage Method for Failed Short-Segment Pedicle Instrumentation in the Treatment of Thoracolumbar Fracture.

Study Design:Retrospective study. Summary of Background Data:Short-segment pedicle instrumentation (SSPI) is widely used to treat thoracolumbar junction fracture. Implant failure is the most common complication of SSPI and often necessitates revision surgery. The stand-alone anterior technique for failed SSPI provides excellent decompression and anterior column reconstruction, but it is incapable of restoring normal stability. High rate of complications is solely attributable to the anterior approach. Thus, the reconstruction of the anterior column with posterior compression instrumentation is the strategy of choice. In this study, we use a modified pedicle subtraction osteotomy (PSO) technique through a single posterior approach as the salvage method for the failed SSPI. Materials and Methods:Thirteen patients with failed SSPI after thoracolumbar fracture were included and followed up at regular intervals. Revision indications include intractable pain, deteriorating neurological deficits, and progressive deformity. The modified PSO was performed. After osteotomy, the anterior cortex was thinned and the anterior longitudinal ligament was also preserved to maintain stability during correction. Autograft was inserted into the osteotomy gap to increase stability and fusion rate. The correction had been achieved with closure. We evaluated the patients’ clinical symptoms, segmental kyphosis correction, bony fusion time, and complications. Results:Segmental kyphosis correction was from preoperative average 20.9 degrees (range, 9.5–38.5 degrees) to 3.0 degrees (range, 1–5.5 degrees) immediately after operation and 6.1 degrees (range, 3–8 degrees at the last follow-up). Bony fusion was confirmed on radiographs in all patients at an average of 9.9 months (range, 7.5–12 mo) after revision surgery. There was no implant failure in any of the 13 patients. Average preoperative visual analog scale was 6.5 (range, 5–9) and reduced to 3.7 (range, 2–5) at the last follow-up. There was also a significant decrease in mean preoperative Oswestry Disability Index from 55.2 (range, 38–76) to 32.8 (range, 16–56). No patients suffered any neurological deterioration related to revision surgery. Complications were encountered in 6 patients (46.1%), including 4 with cerebrospinal fluid leak and 2 with superficial wound infection. All these complications were managed conservatively and none of them underwent reoperation. Conclusion:We conclude that modified PSO possesses the advantages of excellent kyphosis correction, a safe and reliable salvage alternative for the revision of SSPI failure.

Treatment of Lumbar Split Fracture-dislocation with Short- or Long-segment Posterior Fixation and Anterior Fusion.

Study Design: Retrospective analysis of 16 patients. Summary of Background Data: The lumbar split fracture-dislocation is a rare but severe injury, which is type C1.2.1 fracture in the Association for the Study of Internal Fixation spine fracture classification. The axial compressive and torsional force shattered the vertebral body into 2 halves and displaced them rotationally. This kind of fracture is so highly unstable that the treatment is very challenging. Purpose: The purpose of this study was to report and compare on clinical outcome and complications of patients with lumbar split fracture-dislocation which had been treated either short-segment or long-segment posterior fixation and anterior fusion. Materials and Methods: A total of 16 patients with acute, split fracture-dislocation of the lumbar spine from March 2000 to May 2009 in our department were recruited. Seven patients (group I) treated by long-segment posterior fixation (2 levels above and 2 below the fracture) and anterior corpectomy and strut grafting. With the improvement of surgical technique and instrument, 9 patients after August 2004 were treated by short-segment posterior fixation (1 level above and 1 below, and included the fractured vertebrae itself) and anterior discectomy and strut grafting. The intraoperative blood loss, operation time, complications of operation, time to achieve bony fusion, Frankel scale, Oswestry Disability index, and Visual Analogue Pain Scale the Cobb angle were collected and compared. Results: The mean follow-up was 33.4 months for group I and 36.2 months for group II. The operation time was 457.1 minutes in group I which was significantly longer than 240.0 minutes in group II. The total blood loss was for group I was 2001.4 mL (range, 1580–2500 mL) and for group II was 730.6 mL (range, 430–950 mL). There was no neurological deterioration after surgery in both group and no difference in neurological outcome between the 2 groups. The loss of correction in Cobb angle averaged at the final evaluation was 2 and 5 degrees for groups I and II, respectively. There was no radiologically visible pseudarthrosis. The postoperative Visual Analogue Pain Scale score was 3.3 and 2.7 for groups I and II, respectively. In the SF-36 survey, after surgery the domains Role physical and Bodily pain improved significantly only in group B (P<0.05 and P=0.06, respectively). Time to achieve bony fusion in group I was 7.9 months which was significantly longer than 3.8 months in group II. Complications included 3 urinary infections, 1 decubitus ulcer, and 1 superficial infection that were cured by antibiotics. Screw breakage was found in 1 patient in the group II. Conclusions: The lumbar sagittal split fracture-dislocation is a rare but severe injury, which can be treated either with short-segment or long-segment posterior fixation and anterior fusion. The short construct with pedicle screws in the fractured vertebrae followed by the maneuver of rod derotation can obtain anatomic reduction, restoration of 3-column alignment, and decompress the affected neural elements by restoration of the normal canal dimension. It may be a better therapeutic option for the highly unstable lumbar fracture of C1.2.1.