Full-endoscopic lumbar discectomy via lateral superior articular process approach for treating far lateral lumbar disc herniation: a retrospective study and technical note.

PURPOSE: This study aims to evaluate the efficacy and safety of the full-endoscopic lumbar discectomy (FELD) via lateral superior articular process (LSAP) approach and full-endoscopic transforaminal discectomy (FETD) for treating far lateral lumbar disk herniation (FFLDH). METHODS: From January 2020 to June 2022, patients who were diagnosed as FLLDH underwent the FELD via LSAP approach or FETD. The operation time, estimated blood loss, length of hospital stays, and complications were recorded. The visual analog scale (VAS) for back pain, VAS for leg pain, and the Oswestry Disability Index (ODI) scores was measured during preoperative and postoperative follow-up. RESULTS: Thirty-two patients were enrolled in this study, of which 12 patients were treated with the FELD via LSAP approach (LSAP-FELD group) and 20 patients underwent FETD (FETD group). The LSAP-FELD group exhibited significantly shorter operation times and hospital stays compared to the FETD group, while no statistically significant differences were observed in intraoperative blood loss and complication rates. There were no significant differences in the VAS for back pain, the VAS for leg pain, and the ODI score between the two groups preoperatively and three days, three months, and the last follow-up postoperatively. CONCLUSIONS: Both the FELD via LSAP approach and FETD have demonstrated favourable clinical efficacy in the treatment of FLLDH. Notably, the FELD via LSAP approach shows the advantages of shorter operation time and hospital stays.

Development and Validation of a Nomogram to Predict the Risk of Recurrent Lower Extremity Radiating Pain Within 1 Week Following Full-Endoscopic Lumbar Discectomy.

BACKGROUND: Accurately predicting the risk of lower extremity (LE) radiating pain after surgery is an important endeavor for spinal surgeons. Our study aimed to identify risk factors for LE radiating pain after decompression with full-endoscopic lumbar discectomy (FELD) and develop a nomogram. METHODS: We retrospectively reviewed the medical data of patients with lumbar disc herniation who underwent FELD. Two hundred thirty-five patients diagnosed at our hospital from January 2015 to December 2020 were used for model development. The independent risk factors for LE radiating pain after surgery were determined by least absolute shrinkage and selection operator logistic regression and multivariate logistic regression analysis. A nomogram was developed to predict the risk of LE radiating pain based on independent risk factors. Receiver operating characteristic curve, calibration curve, and decision curve analyses were used to evaluate the predictive performance. The nomogram was further verified by an independent cohort. RESULTS: Three hundred seventy-five patients were enrolled in this study, with 102 patients in the training cohort reporting LE radiating pain after FELD, while 133 patients did not. In the validation cohort, 57 patients reported LE radiating pain after FELD, while 83 patients did not. The model was established by multivariate logistic regression analysis. The risk factors included a higher Michigan State University classification of herniated discs, increased disease course, increased time of surgery, reduced lateral recess width, and an interlaminar surgical approach, compared to transforaminal approach. The C-indices and the area under the receiver operating characteristic curve of the predictive model demonstrated good discrimination. Good predictive performance and accuracy were also observed in the validation cohort. CONCLUSIONS: A novel nomogram for predicting recurrent LE radiating pain within 1 week after FELD was established and validated. More aggressive pain management strategies should be considered for patients at high risk of LE radiating pain after surgery, as predicted by this model.

A clinical nomogram for predicting the residual low back pain after percutaneous endoscopic surgery for lumbar disc herniation.

PURPOSE: Current findings suggest that minimally percutaneous endoscopic lumbar discectomy (PELD) is a practical therapeutic approach for lumbar disc herniation (LDH). However, some patients still end up with residual low back pain, even after surgery. Our study aims to construct and validate a nomogram to predict residual low back pain after PELD. METHODS: The medical records of 355 LDH patients admitted to the author's hospital were retrospectively analyzed between January 2019 and December 2021. The patients were randomly divided into two groups with a ratio of 7:3, namely a modelling group and a validation group. The univariable logistics and multivariable regression methods were used to screen the independent risk factors. A nomogram was then drawn using independent risk factors selected from the univariable and multivariable regression analyses. The concordance index (C-index), the receiver operating characteristic (ROC) curve, the calibration curve, and the decision curve analysis were used to evaluate the nomogram's performance. Finally, the accuracy of the nomogram was verified by a validation cohort. RESULTS: 36.6% (130/355) of patients showed low back pain after percutaneous endoscopic lumbar discectomy, while 63.4% (225/355) showed no symptoms. Multivariable logistical regression analysis showed that Modic change (p < 0.05, OR = 1.813), fatty infiltration of the paravertebral muscle (p < 0.05, OR = 2.935), and edema of lumbodorsal fascia (p = 0.049, OR = 1.611) were significant risk factors for post-operative residual back pain. Moreover, the C-index of the predictive nomogram was 0.743 (0.681-0.805), the area under the receiver operating characteristic curve (AUC) value was 0.739, and the DCA results exhibit a net benefit between 0.16 and 0.66. The above internal validation methods demonstrate the nomogram's good predictive capability. CONCLUSION: Each variable in the model had a quantitatively corresponding risk score, which can be used in predicting residual low back pain after PELD.

Analysis of Nanohydroxyapatite/Polyamide-66 Cage, Titanium Mesh, and Iliac Crest in Spinal Reconstruction of the Patients with Thoracic and Lumbar Tuberculosis.

Background: The standard recommended and common reconstruction method for spinal tuberculosis is titanium mesh bone graft and autogenous iliac crest. However, these methods have their own disadvantages. Objective: To evaluate the clinical efficacy of one-stage posterior debridement with iliac bone graft, titanium mesh bone graft, or nanohydroxyapatite/polyamide-66 cage in thoracic and lumbar tuberculosis. Materials and Methods: Between January 2013 and December 2018, 57 patients with thoracic or lumbar tuberculosis were treated by interbody bone graft combined with posterior internal fixation after debridement. Thirteen patients were treated with iliac bone graft to construct the stability of the vertebral body, 26 patients were treated with titanium mesh bone graft, and 18 patients were treated with nanohydroxyapatite/polyamide-66 cage bone graft. The main clinical results were evaluated by intervertebral height, cage subsidence, operation time, operative blood loss, postoperative hospitalization, postoperative complications, visual analog scale (VAS) score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), American Spinal Injury Association (ASIA) grade, and bone graft fusion time. All the outcomes were recorded and analyzed by statistical methods. Results: The mean follow-up time was 24.5 months. Neurologic function was improved in most patients at the last follow-up. There were significant differences in ESR, CRP, and VAS score between preoperative and postoperative values; however, there were no significant differences in ESR, CRP, and VAS score among the three groups. There were no significant differences in operation time, blood loss, postoperative hospitalization, and postoperative complications among the three groups at discharge. There was no significant difference in ASIA grade among the three groups at the last follow-up. Nanohydroxyapatite/polyamide-66 cage group had a lower cage subsidence (P = 0.013). The bone graft fusion time of the nanohydroxyapatite/polyamide-66 cage group was significantly shorter than the iliac bone graft group and the titanium mesh bone graft (P < 0.05). Conclusions: The follow-up outcomes showed that the method involving one-stage posterior debridement and internal fixation, interbody graft, and fusion is an effective and safe surgical method for patients with thoracic and lumbar tuberculosis. The incidence rate of cage subsidence was less and the bone graft fusion time was shorter with nanohydroxyap atite/polyamide 66 cage when compared with iliac bone graft and titanium mesh bone graft in the surgical treatment of thoracic and lumbar tuberculosis. Nanohydroxyapatite/polyamide-66 cage has a promising application prospect to be a new bone graft material.

Comparison of Postoperative Outcomes Between Percutaneous Endoscopic Lumbar Interbody Fusion and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Spinal Stenosis.

Objective: This study aimed to compare postoperative outcomes in surgical and patient-reported outcomes (PROs) between percutaneous endoscopic lumbar interbody fusion (PE-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of lumbar spinal stenosis (LSS). Methods: We reviewed a total of 89 patients undergoing single-level surgery for lumbar spinal stenosis from January 2018 to July 2021. The cases were categorized as PE-LIF (Group PE-LIF, 41 cases) or MIS-TLIF (Group MIS-TLIF, 48 cases) approach. Parameters obtained at baseline through at least six months of follow-up were collected. The surgical outcomes involving the operative time, estimated blood loss, postoperative bed staying time, and length of hospital stays were analyzed. PROs included the Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), modified MacNab standard evaluation, intervertebral fusion rate, and postoperative complications. Results: A total of 89 patients were included in this analysis involving 41 patients who underwent PE-LIF and 48 patients who underwent MIS-TLIF. The 2 groups were similar in gender, age, body mass index, follow-up time and surgery levels (P > 0.05), and were not significantly different in the length of hospital stays (P > 0.05). PE-LIF had a significantly longer operative time, greater fluoroscopy time, lower estimated blood loss and shorter bed rest time than MIS-TLIF. Both groups improved significantly from baseline for the VAS and ODI scores. PE-LIF was associated with a lower VAS score for back pain at three-day after surgery. There were no significant differences between PE-LIF and MIS-TLIF in the excellent or good rates and intervertebral fusion rates at the last follow-up (P > 0.05). As for related complications, there were no significant complications occurred, and no significant differences were seen in the complications between both groups (P > 0.05). Conclusions: To summarize, PE-LIF and MIS-TLIF are both safe and effective for LSS. PE-LIF has a definite short-term curative effect with less trauma.

Posterior unilateral approach with 270° spinal canal decompression and three-column reconstruction using double titanium mesh cage for thoracic and lumbar burst fractures.

Objective: To evaluate the clinical effects of the posterior unilateral approach with 270° spinal canal decompression and three-column reconstruction using double titanium mesh cage (TMC) for thoracic and lumbar burst fractures. Materials and methods: From May 2013 to May 2018, 27 patients with single-level thoracic and lumbar burst fractures were enrolled. Every patient was followed for at least 18 months. Demographic data, neurologic status, back pain, canal compromise, anterior body compression, operative time, estimated blood loss and surgical-related complications were evaluated. Radiographs were reviewed to assess deformity correction, anterior body height correction, bony fusion and TMC subsidence. Results: The average preoperative percentages of canal compromise and anterior body height compression were 58.4% and 50.5%, respectively. All surgeries were successfully completed in one phase, the operative time was 151.5 ± 25.5 min (range: 115-220 min), the estimated blood loss was 590.7 ± 169.9 ml (range: 400-1,000 ml). Neurological function recovery was significantly improved except for 3 grade A patients. The preoperative visual analog scale (VAS) scores for back pain were significantly decreased compared with the values at the last follow-up (P = 0.000). The correct deformity angle was 12.4 ± 4.7° (range: 3.9-23.3°), and the anterior body height recovery was 96.7%. The TMC subsidence at the last follow-up was 1.3 ± 0.7 mm (range: 0.3-3.1 mm). Bony fusion was achieved in all patients. Conclusion: The posterior unilateral approach with 270° spinal canal decompression and three-column reconstruction using double TMC is a clinically feasible, safe and alternative treatment for thoracic and lumbar burst fractures.

Efficacy of preoperative screening and decolonization for staphylococcus aureus in total joint arthroplasty: A meta-analysis.

The purpose of this study is to conduct a meta-analysis to evaluate the efficacy of screening and decolonization protocol for Staphylococcus aureus (SA) in total joint arthroplasty (TJA). We systematically searched the electronic databases of PubMed, Embase and Cochrane databases for relevant literatures from January 2000 to September 2020. The outcomes were colonization rate, total-surgical site infection (SSI) rate, SA-SSI rate and methicillin-resistant Staphylococcus aureus (MRSA)-SSI rate. All calculations and statistical tests were performed using Stata 14.0 software. A total of 12 studies were eligible in this study. Compared with control group, the screening and decolonization group had lower risks in total-SSI (risk ratio (RR) = 0.52; 95% confidence interval (CI): 0.40-0.67), SA-SSI (RR = 0.48; 95% CI: 0.32-0.72) and MRSA-SSI (RR = 0.45; 95% CI: 0.21-0.96). The nasal SA colonization was found to be associated with higher accidences of SSI involving total-SSI (RR = 1.49; 95% CI: 1.02-2.18), SA-SSI (RR = 2.51; 95% CI: 0.97-6.50) and MRSA-SSI (RR = 7.84; 95% CI: 1.67-36.79). The colonization rate of SA was significantly reduced after decolonization. No difference was observed between universal decolonization and screening-based decolonization. In conclusion, colonization of SA is associated with increased risk of SSI in TJA. Screening and decolonization protocol are proven to be effective to reduce colonization of SA and present protective effects against SSI in TJA. Moreover, universal decolonization protocol is non-inferior to screening-based decolonization.

Effect of RTS versus percutaneous conventional pedicle screw fixation on type A thoracolumbar fractures: a retrospective cohort study.

PURPOSE: This study aims at evaluating the effects of RTS (rotation softened trauma fixation system) compared with PCPSF (percutaneous conventional pedicle screw fixation) on type A thoracolumbar fractures. METHODS: In this retrospective cohort study, 116 patients with type A thoracolumbar fractures from March 2014 to June 2018 were enrolled. PCPSF was performed in 60 patients, meanwhile the other 56 patients accepted RTS. VAS scores, Cobb angle, anterior vertebral height (AVH) and perioperative data were compared between the two groups. RESULTS: Both groups were consistent with baseline on demographic and clinical characteristics. No significant difference was observed in VAS score between-group before and after operation. One year after surgery, the VAS score of RTS group was lower than that of PCPSF group (0.7 ± 0.3 vs. 1.5 ± 0.4). The postoperative AVH (%) in PCPSF was 82.3% (95%CI, 81.7-84.6), and 91.78% (95% CI, 91.1-92.4) in RTS. The postoperative improvement rate of AVH (%) in RTS was higher than that in PCPSF (30.6 ± 5.0 [95% CI, 29.2-32.0] vs. 22.0 ± 7.3 [95% CI, 20.2-24.2]). The postoperative Cobb angle (°) in PCPSF was 2.6 ± 3.4 (95%CI,11.7-13.5), and 7.5 ± 2.0 (95%CI,7.0-8.0) in RTS. The postoperative correction of Cobb angle (°) in RTS was higher than that in PCPSF (16.1 ± 3.8 95%CI,15.1-17.1] vs. 11.6 ± 5.2 95%CI,10.3-13.1]). CONCLUSIONS: Compared with PCPSF, RTS has advantages in restoring the anterior vertebral height and reducing local kyphosis.

Novel unilateral C1 double screw and ipsilateral C2 pedicle screw placement combined with contralateral laminar screw-rod fixation for atlantoaxial instability.

PURPOSE: To investigate the anatomical and biomechanical feasibility of the unilateral C1 double screw [pedicle screw (PS) + lateral mass screw (LMS)] and ipsilateral C2 PS combined with contralateral C2 laminar screw (LS)-rod fixation for atlantoaxial instability by comparison with traditional posterior fixation methods. METHODS: Fifteen sets of complete dry bony specimens of atlas were used for morphometric analysis. The working length, width and thickness of the C1 PSs and LMSs were manually measured. Ten fresh-frozen cervical spines (C0-C7) were used to complete the range of motion (ROM) testing in their intact condition, under destabilization and after stabilization by the following procedures: unilateral C1-C2 PS rod fixation (Group A), bilateral C1-C2 PS rod fixation (Group B), and unilateral C1 double screw and ipsilateral C2 PS combined with contralateral C2 LS rod fixation (Group C). RESULTS: The working thickness of the C1 PS was ≤ 3.5 mm in only one (1/15 = 6.7%) specimen. The other parameters were > 3.5 mm in all specimens. In the ROM test, all fixation groups showed significantly reduced flexibility in all directions compared with both the intact and destabilization groups. Further, Groups B and C showed better stability in all directions than Group A. However, no significant differences were observed between Groups B and C. CONCLUSION: The C1 unilateral lateral mass could mostly contain two screws(PS + LMS) with diameters ≤ 3.5 mm. The novel technique of unilateral C1 double screw and ipsilateral C2 PS combined with contralateral C2 LS rod fixation provided better stability than unilateral PS rod fixation and similar as bilateral PS rod fixation. Therefore, it is a feasible salvage method that provides a new insight into atlantoaxial instability. These slides can be retrieved under Electronic Supplementary Material.

Adenovirus-mediated expression of vascular endothelial growth factor-a potentiates bone morphogenetic protein9-induced osteogenic differentiation and bone formation.

Mesenchymal stem cells (MSCs) are suitable seed cells for bone tissue engineering because they can self-renew and undergo differentiation into osteogenic, adipogenic, chondrogenic, or myogenic lineages. Vascular endothelial growth factor-a (VEGF-a), an angiogenic factor, is also involved in osteogenesis and bone repair. However, the effects of VEGF-a on osteogenic MSCs differentiation remain unknown. It was previously reported that bone morphogenetic protein9 (BMP9) is one of the most important osteogenic BMPs. Here, we investigated the effects of VEGF-a on BMP9-induced osteogenesis with mouse embryo fibroblasts (MEFs). We found that endogenous VEGF-a expression was undetectable in MSCs. Adenovirus-mediated expression of VEGF-a in MEFs potentiated BMP9-induced early and late osteogenic markers, including alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). In stem cell implantation assays, VEGF-a augmented BMP9-induced ectopic bone formation. VEGF-a in combination with BMP9 effectively increased the bone volume and osteogenic activity. However, the synergistic effect was efficiently abolished by the phosphoinositide 3-kinase (PI3K)/AKT inhibitor LY294002. These results demonstrated that BMP9 may crosstalk with VEGF-a through the PI3K/AKT signaling pathway to induce osteogenic differentiation in MEFs. Thus, our findings demonstrate the effects of VEGF-a on BMP9-induced bone formation and provide a new potential strategy for treating nonunion fractures, large segmental bony defects, and/or osteoporotic fractures.

Evodiamine inhibits the proliferation of human osteosarcoma cells by blocking PI3K/Akt signaling.

Osteosarcoma (OS) is the most common non-hematologic primary malignancy of bone, and multiple chemotherapeutic agents have been applied in the treatment of OS for over 40 years. Nevertheless, due to the poor prognosis of OS, it is essential to develop a novel treatment strategy. Evodiamine (EVO), a quinolone alkaloid extracted from the fruit of Evodia rutaecarpa, has been demonstrated to inhibit tumor cell proliferation. Thus, the main aim of the present study was to investigate the anti-proliferative and apoptosis-inducing effects of evodiamine (EVO) on human OS 143B cells, but also the possible mechanisms underlying these effects. The results of crystal violet staining, flow cytometry, western blot analysis and an in vivo experiment demonstrated that EVO exhibits significant inhibitory effects on cell proliferation, exhibits apoptosis-inducing effects and arrests the cell cycle in 143B cells. According to our findings of polymerase chain reaction (PCR), western blot analysis and recombinant adenoviral transfection, we confirmed that EVO upregulates both the protein and gene levels of phosphatase and tensin homolog (PTEN) in a concentration-dependent manner in 143B cells. Overexpression of PTEN reinforced the anti-proliferative effect of EVO in the 143B cells, while knockdown of PTEN upregulated PI3K/Akt signaling transduction and reversed the inhibitory effect of EVO on 143B cell proliferation. Further analysis indicated that EVO upregulated the expression of PTEN by inactivating PI3K/Akt signaling by decreasing phosphorylated Akt1/2. Based on the above results, we conclude that PTEN/PI3K/Akt signaling is involved in the inhibitory effect on human OS 143B cell proliferation by EVO.

Percutaneous vertebroplasty combined with percutaneous pediculoplasty for lytic vertebral body and pedicle lesions of metastatic tumors.

BACKGROUND: Percutaneous pediculoplasty (PP) consists of the injection of Poly(methyl methacrylate) (PMMA) into the fractured pedicle or lytic vertebral pedicle lesions, as a technique derived from vertebroplasty. OBJECTIVES: To evaluate the short-term analgesic effect of percutaneous vertebroplasty (PV) and percutaneous pediculoplasty (PP) in patients with lytic vertebral body and pedicle lesions of metastatic tumors. STUDY DESIGN: Single-center retrospective observational study. SETTING: An interventional pain management practice, a medical center, major metropolitan city, China. METHODS: Single-center retrospective observational study of all patients managed with PV and PP for painful vertebral body and pedicle metastatic tumors between 2007 and 2013. For each patient, symptom duration and pain intensity were recorded. PP was performed under local analgesia, in the prone position, with C-arm fluoroscopy guidance. The mixture of PMMA and Doxorubicin was delivered into the vertebral body with a non-beveled needle for the initial treatment followed by the mixture delivery into the lytic pedicle during needle withdrawal. RESULTS: Nine patients (5 women, 4 men) were enrolled in the study with a mean age of 65.9 years (range 57 - 75). Technical success was defined as the ability to access the lesion using the approach. A positive clinical response for pain relief was achieved in these patients in whom vertebroplasty and pediculoplasty had been performed. Pain level was not significantly reduced in 3 patients in whom just vertebroplasty has been performed because the medial wall of the pedicle was destroyed by the metastatic lesion. LIMITATIONS: This study is limited by its sample size. CONCLUSIONS: PV and PP via the transpedicular approach for infiltrated vertebral bodies and infiltrated pedicles of metastatic tumors may be considered a valid therapeutic option.

Anterior retropharyngeal approach to C1 for percutaneous vertebroplasty under C-arm fluoroscopy.

BACKGROUND CONTEXT: Percutaneous vertebroplasty (PVP) has proven to be a valuable palliative treatment option for patients with medically refractory painful osteolytic metastases of the spine. Percutaneous vertebroplasty of the atlas has been reported in only seven articles and has been performed with different techniques and approaches. PURPOSE: To describe the technique we used to perform PVP of a lytic lesion of the lateral mass of C1 via anterior retropharyngeal approach guided by C-arm fluoroscopy. STUDY DESIGN: A technical report. PATIENT SAMPLE: It included a 75-year-old man with known metastatic lung carcinoma and incapacitating right suboccipital and neck pain refractory to conventional medical treatment. Radiologic evaluation showed revealed osteolytic destruction of C1 and C2, mainly invading the right lateral mass of C1 and the vertebral body of C2. OUTCOME MEASURES: The right suboccipital and neck pain was measured using the visual analog scale (VAS). METHODS: Under C-arm fluoroscopy, a novel anterior retropharyngeal approach, through the vertebral body of C2 into the metastatic osteolytic vertebral lesion of C1, was performed to achieve the PVP in C1 followed by a PVP in C2. RESULTS: Immediately after the operation, the patient reported substantial pain relief (from VAS 9/10 preoperatively to 3/10). At 12 hours postoperatively, the range of motion was also improved. There were no surgery-related complications. The immediately postoperative cervical plain film and computed tomography scan showed adequate filling of the osteolytic lesion without the obvious leakage of bone cement. Clinical follow-up at 3 months revealed that this pain condition was improved and maintained (VAS 1/10). CONCLUSIONS: When the transoral approach is unsuitable or contraindicated, the anterior retropharyngeal approach could be an efficacious alternative in selected patients with C1 metastasis, providing adequate filling of bone cement and significant pain relief. Based on our preliminary exploration, only assisted by C-arm fluoroscopy, this approach is feasible to achieve PVP in C1 under local anesthesia and intravenous analgesia. Nevertheless, when considering the substantial potential risks, this technically challenging procedure should be performed by experienced operators.

Clinical application of the paraspinal erector approach for spinal canal decompression in upper lumber burst fractures.

OBJECTIVE: Percutaneous pedicle screw fixation is commonly used for upper lumber burst fractures. The direct decompression remains challenging with this minimally invasive surgery. The objective was to evaluate a novel paraspinal erector approach for effective and direct decompression in patients with canal compromise and neurologic deficit. METHOD: Patients (n = 21) with neurological deficiency and Denis B type upper lumbar burst fracture were enrolled in the study, including 14 cases in the L1 and 7 cases in the L2. The patients underwent removal of bone fragments from the spinal canal through intervertebral foramen followed by short-segment fixation. Evaluations included surgery-related, such as duration of surgery and blood loss, and 12-month follow-up, such as the kyphotic angle, the height ratio of the anterior edge of the vertebra, the ratio of sagittal canal compromise, visual analog scale (VAS), Oswestry Disability Index (ODI), and Frankel scores. RESULTS: All patients achieved direct spinal canal decompression using the paraspinal erector approach followed by percutaneous pedicle screw fixation. The mean operation time (SD) was 173 (23) min, and the mean (SD) blood loss was 301 (104) ml. Significant improvement was noted in the kyphotic angle, 26.2 ± 8.7 prior to operation versus 9.1 ± 4.7 at 12 months after operation (p < 0.05); the height ratio of the anterior edge of the injured vertebra, 60 ± 16% versus 84 ± 9% (p < 0.05); and the ratio of sagittal canal compromise, 46.5 ± 11.4% versus 4.3 ± 3.6% (p < 0.05). Significant improvements in VAS (7.3 ± 1.2 vs. 1.9 ± 0.7, p < 0.05), ODI (86.7 ± 5.8 vs. 16.7 ± 5.1, p < 0.05), and Frankel scores were also noted. CONCLUSIONS: The paraspinal erector approach was effective for direct spinal canal decompression with minimal injury in the paraspinal muscles or spine. Significant improvements in spinal function and prognostics were achieved after the percutaneous pedicle screw fixation.

Anterior or posterior approach of full-endoscopic cervical discectomy for cervical intervertebral disc herniation? A comparative cohort study.

STUDY DESIGN: This is a retrospective comparative cohort study. OBJECTIVE: To compare the outcomes of patients with symptomatic cervical intervertebral disc herniation (CIVDH) treated with full-endoscopic cervical discectomy (FECD) using the anterior approach with those treated with the posterior approach. SUMMARY OF BACKGROUND DATA: The optimal FECD surgical approach for CIVDH remains controversial. METHODS: From March 2010 to July 2012, a total of 84 consecutive patients with symptomatic single-level CIVDH who underwent FECD using the anterior approach (42 patients) or the posterior approach (42 patients) were enrolled. Patients were assessed neurologically before surgery and followed up at regular outpatient visits. The clinical outcomes were evaluated using the visual analogue scale and the modified MacNab criteria. Radiographical follow-up included the static and dynamic cervical plain radiographs, computed tomographic scans, and magnetic resonance images. RESULTS: In both groups, shorter mean operative time (63.5 min vs. 78.5 min), increased mean volume of disc removal (0.6 g vs. 0.3 g), larger mean decrease in the final postoperative mean intervertebral vertical height (1.0 mm vs. 0.5 mm), and longer mean hospital stay (4.9 d vs. 4.5 d) were observed in the anterior full-endoscopic cervical discectomy group. Postoperatively, the clinical outcomes of the 2 approaches were significantly improved, but the differences between the 2 approaches were not significant (P = 0.211 and P = 0.257, respectively). Four surgery-related complications were observed among all enrolled patients (complications in each group were 2; overall 4 of 84, 4.8%). CONCLUSION: In our study, the clinical outcomes between the 2 approaches did not differ significantly. Nevertheless, posterior full-endoscopic cervical discectomy may be preferable when considering the volume of disc removal, length of hospital stay, and the postoperative radiographical changes. As an efficacious supplement to traditional open surgery, FECD is a reliable alternative treatment of CIVDH and its optimal approach remains open to discussion. LEVEL OF EVIDENCE: 3.

Clinical measurement of intravertebral pressure during vertebroplasty and kyphoplasty.

BACKGROUND: Vertebroplasty (VP) and kyphoplasty (KP) are emerging procedures for almost immediate pain relief when treating osteoporotic or osteolytic fractures. The main reported complication is polymethylmethacrylate (PMMA) leakage, which may lead to compression of neural structures or embolism. Different authors have proposed that intravertebral pressure (IP) is an important factor determining the risk for leakage, although so far only limited information has been gathered from clinical and experimental studies. There is also a lack of understanding of the IP during conventional interventions in VP and KP in the clinic. OBJECTIVE: (1) To compare the intravertebral pressures of compressed vertebrae and adjacent normal vertebrae. (2) To measure the IP of compressed vertebrae during VP and KP. SETTING: An interventional pain management practice, a medical center, major metropolitan city, in the People's Republic of China. METHODS: Thirty-five patients (with 40 compressed vertebrae and 35 adjacent normal vertebrae) were randomly allocated for intravertebral pressure measurements. Cannulas were placed bipedicularly into the posterior third of each vertebral body. Either PMMA or a balloon was injected into the vertebral body through the right cannula. A manometer was connected to the cannula in the left pedicle, and heparin was injected to verify the pressure measurement system. RESULTS: The range (minimum-maximum), average IP, and the standard deviation of the compressed vertebrae were 0-39 mm Hg and 24.5 ±11.3 mm Hg; and that of adjacent normal vertebrae were 3-16 mm Hg, 7.3 ± 4.2 mm Hg. Furthermore, the average IP for Phase 1 (before PMMA injection) for VP was 23 ±11.9 mm Hg; the maximum IP recorded during injection was 169 ± 46.8 mm Hg and the IP for 10 minutes after injection was 33 ±9.4 mm Hg. Meanwhile, the highest IP recorded for KP patients was 142 ±39.6 mm Hg. The average IP for Phase 1 (before balloon inflation) was 24 ±12.7 mmHg; Phase 2 (peak IP during the balloon inflation) was 63 ± 25.8 mm Hg; and Phase 3 (after balloon inflation/before PMMA injection) was , and 18 ± 10.8 mm Hg. The IP for 10 minutes after injection in KP patients was 36 ± 8.5 mm Hg. LIMITATIONS: The flow rate was manually controlled, which is in line with clinical routine, and was kept at approximately 0.1 mL/s. Because the speed of injection was controlled by hand, an exact injection rate could not be assured, leading to some inaccuracy when comparing the IP of VP and KP patients. Each patient was injected with a different PMMA volume. Because PMMA injection was performed to a satisfactory vertebral body filling and limited by any signs of extravasation, it was difficult to maintain a constant injection volume, unlike in vitro studies. Other factors such as the damage to the vertebral shell or the degree of osteoporosis might also have affected the intravertebral pressure. CONCLUSION: This study showed that the IP of compressed vertebrae was significantly higher than that of adjacent normal vertebrae. There was a significant increase in IP during the PMMA filling in VP and KP; the IP of compressed vertebrae was not significantly reduced by the balloon inflation in KP, and no statistically significant differences in IP were found during all common stages of PMMA filling in VP and KP.