Guohua Lü

An evaluation of the learning curve for a complex surgical technique: the full endoscopic interlaminar approach for lumbar disc herniations

BACKGROUND CONTEXT Compared with conventional microsurgical technique, the full endoscopic (FE) interlaminar approach is a more minimally invasive technique for the surgical treatment of lumbar disc herniations. Its efficacy and safety have been confirmed by numerous studies. However, a steep learning curve with the use of such a complex technique is a major concern for the initial adoption of this technique. PURPOSE To evaluate the learning curve of using an FE interlaminar technique for the surgical treatment of lumbar disc herniation. STUDY DESIGN A prospective study of patients with lumbar disc herniation who underwent discectomy via interlaminar approach assisted by FE instruments. PATIENT SAMPLE Thirty patients with lumbar disc herniation underwent discectomy using an interlaminar endoscopic-only approach between 2008 and 2009. METHODS The patients were divided into three groups of 10 sequential cases each. Group A consisted of the first 10 cases, Group B the subsequent 10 cases, and Group C the last 10 cases. The clinical evaluation data included operative time, length of hospital stay, visual analog scale (VAS) leg and back pain scores, complications, and rate of conversion to an open. RESULTS All patients were observed prospectively for 1.61 ± 0.22 years (range, 1.2-2.0 years). There was no measurable intraoperative bleeding and postoperative infections in the three groups. Compared with Group A, the operative time in Group B was significantly decreased (p < .001). The patients in Group C had much less operative time than in Group B (p = .002). There was no significant difference with length of hospital stay in the three groups (p = .897). The improvement of VAS leg and back pain scores in each group was similar: there was a significant improvement (p < .01) at 3 months after surgery when compared with preoperative scores, but there was no statistical difference (p > .05) in the VAS leg and back pain scores between 3 months after surgery and final follow-up. The complication rate was 12.5% for Group A, 10% for Group B, and 0% for Group C. The need for conversion to an open procedure for Group A was 20% compared with zero cases in both Groups B and C. There were no symptomatic recurrences in our study. CONCLUSIONS Excellent clinical and minimally invasive outcomes can be obtained in the surgical treatment of lumbar disc herniation via the interlaminar approach assisted by FE technique. However, attention must be paid to the steep learning curve by using this complex technique. Imprecise anatomic orientation and manipulation inside the spinal canal are key factors in the steep learning curve. Obtaining microsurgical experience, attending workshops, and suitable patient selection can help shorten the learning curve and decrease the complications.

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.

Endoscopically Assisted Anterior Release and Reduction Through Anterolateral Retropharyngeal Approach for Fixed Atlantoaxial Dislocation

Study Design. A prospective study. Objective. To evaluate a novel technique involving an endoscopically assisted anterior release and reduction through an anterolateral retropharyngeal approach with minimum follow-up interval of 31 months. Summary of Background Data. Irreducible atlantoaxial dislocation is typically a chronic process that requires surgical treatment. However, the current literature does not agree on the single best method of treatment. Previously, the best outcomes have been reported with transoral reduction followed by anterior or posterior fixation. Despite recent innovations, numerous complications remain associated with this approach. Methods. About 21 consecutive irreducible atlantoaxial dislocation patients with mean age of 32 years underwent endoscopically assisted anterior release and reduction through the anterolateral retropharyngeal approach followed by posterior fixation. The primary pathologies included 8 late odontoid fractures, 7 cases of os odontoideum, 5 with laxity of the transverse ligament, and 1 with atlanto-occipital assimilation with a hypoplastic odontoid. Neurologic status was evaluated using the Japanese Orthopedic Association scoring system. Radiographic parameters including the atlantodental interval (ADI) and cervicomedullary angle were also measured. Follow-up data were obtained for a minimum of 31 months. Results. Anatomic reduction was achieved in 20 cases and near-anatomic reduction in 1 case. All patients had an uneventful recovery with significant improvement in neurologic function and radiographic parameters. No complications were seen. The atlantodental interval was corrected from an average 6.3 mm before surgery to 2.7 mm after surgery (P < 0.01). The cervicomedullary angle was also corrected from an average 109° before surgery to 152° after surgery (P < 0.01). Preoperative muscle strength was on average 3.5 (on scale from 1 to 5) and improved after surgery to 4.5 (P < 0.01). The average preoperative and postoperative Japanese Orthopedic Association scores were 9.6 and 15.5, respectively, indicating 82.8% improvement. Conclusion. Endoscopically assisted anterior retropharyngeal release combined with posterior fixation is a safe and effective alternative for the treatment of irreducible atlantoaxial dislocation.

Surgical treatment based on pedicle screw instrumentation for thoracic or lumbar spinal Langerhans cell histiocytosis complicated with neurologic deficit in children

BACKGROUND CONTEXT Surgical indications and procedures for spinal Langerhans cell histiocytosis (LCH) in children are still controversial. Reports containing large samples of surgically treated patients are few in the currently available literature, and the reported operative procedures were also somewhat obsolete. So, further investigation based on large-sample cases and using improved surgical techniques is beneficial and helpful to refine the treatment strategy. PURPOSE To recommend a reasonable treatment strategy for thoracic or lumbar spine LCH in children complicated with neurologic deficit. STUDY DESIGN/SETTING Retrospective/academic medical center. PATIENT SAMPLE Twelve children aged from 2 to 16 years old with the diagnosis of thoracic or lumbar spinal LCH accompanied by neurologic deficit received surgical treatment from January 2005 to January 2010. OUTCOME MEASURES Frankel scale for neurologic function, fusion of the mass, and recurrence of the lesion. METHODS All 12 patients presented initially with local pain and progressive neurologic detriment. Neurologic evaluation revealed two patients with Frankel Grade B, eight with Grade C, and two with Grade D. Radiographic features were positive for typical vertebra plana, a space-occupying mass in the spinal canal compressing neural elements, and a spinal canal encroachment rate more than 50%. Posterior instrumentation with pedicle screw combined with anterior corpectomy, decompression, and support bone graft was performed in the first seven patients as a one-stage procedure. In the remaining five patients, posterior pedicle screw fixation, laminectomy for decompression (via excision of the tumor-like mass), and repair of laminae with allograft bone block were performed. The collapsed vertebral body was left untouched. No chemotherapy or radiotherapy was administrated postoperatively in any of the cases. RESULTS The mean follow-up duration was 43.3 months. The mean operation time was 330 minutes with combined procedure and 142 minutes with single posterior approach (p=.000). The average blood loss was 933 mL with combined procedure and 497 mL with single posterior approach (p=.039). Three of seven patients who received combined surgery encountered approach-related complications, that is, one with intercostal neuralgia and two with pleural effusion. No severe neurologic deteriorate, instrumentation failure, or disease recurrence was detected at follow-up. Neurologic function completely recovered in all 12 patients from 2 to 12 weeks after surgery. The anterior bone graft fused and shaped well in all seven patients, and allograft bone block for lamina repair also achieved complete fusion in the remaining five patients. The internal fixator was removed at 3 to 5 years (average 4.1 years) after initial operation in six patients. No deformity, including scoliosis and kyphosis, has been identified during follow-up period in both procedures. CONCLUSIONS For spinal LCH patients, neurologic deficit is a main indication for operative treatment to prevent permanent and serious consequences. Surgery provides an opportunity for rapid recovery of neurologic function. Both combined and single-stage posterior approaches based on pedicle screw instrumentation techniques are similarly effective in relieving neurologic compression. However, single-stage posterior approach is more favorable with less complications, and preserving involved vertebral body is not a latent hazard of recurrence.

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.

LncRNA H19 targets miR-22 to modulate H2O2-induced deregulation in nucleus pulposus cell senescence, proliferation, and ECM synthesis through Wnt signaling

Intervertebral disc (IVD) degeneration (IDD) is a major contributor to low back pain. During IDD progression, ROS can be produced in the form of H2O2 in nucleus pulposus cells (NPCs) in response to elevated cytokines, leading to subsequent alternations of cell fate and metabolic processes. Genetic factors are considered as main contributors to IDD pathopoiesis. Herein, we investigated the detailed function and mechanism of H19, one of the most up‐regulated lncRNAs in IDD specimens, in H2O2‐induced cell senescence model in NPCs. H19 could accelerate H2O2‐induced degenerative changes by promoting cell senescence, increasing ADAMTS‐5 and MMPs protein levels and Collagen I content, as well as suppressing NPC proliferation through activating Wnt/β‐catenin signaling. Moreover, miR‐22, a direct target of H19, could bind to the 3′UTR of LEF1 to inhibit its expression and reverse the effect of H19 on NPCs, thus inhibiting Wnt/β‐catenin signaling. Taken together, H19 acts as a ceRNA to compete with LEF1 for miR‐22, thus modulating downstream Wnt/β‐catenin signaling in NPCs; H19/miR‐22/LEF1 might be a novel target for improving H2O2‐induced NPC senescence and treatment for IDD.

Cervical Disk Arthroplasty Versus Anterior Cervical Decompression and Fusion for the Treatment of 2-Level Cervical Spondylopathy: A Systematic Review and Meta-analysis.

Study Design:Systematic review and meta-analysis. Objective:To assess the safety and efficacy of cervical disk arthroplasty (CDA) compared with anterior cervical decompression and fusion (ACDF) for the treatment of 2-level cervical spondylopathy. Summary of Background Data:CDA has emerged as a potential alternative to ACDF in patients with cervical disk degeneration. But there are no published systematic reviews and meta-analyses comparing CDA with ACDF for the treatment of 2-level cervical spondylopathy. Methods:The Pubmed, Embase, Web of science, Scopus, and Cochrane library databases were searched comparing CDA to ACDF in patients with 2-level cervical spondylopathy. Outcome measures were neck disability index, visual analog scale (VAS) of arm and neck pain, range of movement (ROM) at C2–C7, functional segment unit ROM, ROM at the operated level, and incidence of radiologic changes at adjacent levels approximately 2 years after surgery, as well as operating time and incidence of surgery-related complications. Mean difference (MD), odds ratios (OR), and their corresponding 95% confidence intervals (95% CIs) were calculated. Results:Six studies involving 646 patients were included. There were no significant differences in neck disability index (MD, −1.53; 95% CI −3.80 to 0.73), VAS neck pain (MD, −0.19; 95% CI −0.71 to 0.33), and VAS arm pain (MD, −0.23; 95% CI −0.61 to 0.16) between 2-level CDA and 2-level ACDF cases. ROM at C2–C7 (MD, 15.82; 95% CI, 10.66–20.99), functional segment unit ROM (MD, 8.58; 95% CI, 7.93–9.23), and ROM at the operated level (MD, 9.54; 95% CI, 7.73–11.35) were greater, but the incidence of radiologic changes at adjacent levels (OR, 0.29; 95% CI, 0.13–0.67) were lower, in 2-level CDA cases. In 2-level CDA cases, the operating time was longer (MD, 57.41; 95% CI, 24.67–90.14), but surgery-related complications rates (OR, 0.47; 95% CI, 0.30–0.74) was lower. Conclusions:CDA may be a safe and effective alternative to ACDF for the treatment of 2-level cervical degenerative disease. Level of Evidence:Level II.

The significance of removing ruptured intervertebral discs for interbody fusion in treating thoracic or lumbar type B and C spinal injuries through a one-stage posterior approach.

Objectives To identify the negative effect on treatment results of reserving damaged intervertebral discs when treating type B and type C spinal fracture-dislocations through a one-stage posterior approach. Methods This is a retrospective review of 53 consecutive patients who were treated in our spine surgery center from January 2005 to May 2012 due to severe thoracolumbar spinal fracture-dislocation. The patients in Group A (24 patients) underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression. In Group B (29 patients), the patients underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression evacuating of the ruptured disc and inserting of a bone graft into the evacuated disc space for interbody fusion. The mean time between injury and operation was 4.1 days (range 2–15 days). The clinical, radiologic and complication outcomes were analyzed retrospectively. Results Periodic follow-ups were carried out until an affirmative union or treatment failure took place. A progressive kyphosis angle larger than 10°, loss of disc height, pseudoarthrosis, recurrence of dislocation or subluxation, or instrument failure before fusion were considered treatment failures. Treatment failures were detected in 13 cases in Group A (failure rate was 54.2%). In Group B, there were 28 cases in which definitive bone fusion was demonstrated on CT scans, and CT scans of the other cases demonstrated undefined pseudoarthrosis without hardware failure. There were statistically significant differences between the two groups (p<0.001 chi-square test). The neurologic recoveries, assessed by the ASIA scoring system, were not satisfactory for the neural deficit patients in either group, indicating there was no significant difference with regard to neurologic recovery between the two groups (p>0.05 Fishers exact test). Conclusion Intervertebral disc damage is a common characteristic in type B and C spinal fracture-dislocation injuries. The damaged intervertebral disc should be removed and substituted with a bone graft because reserving the damaged disc in situ increases the risk of treatment failure.

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.