Cortical Trajectory Screw Fixation in Lumbar Spine Surgery: A Review of the Existing Literature

Posterior lumbar fusion is a safe and effective surgical method for diseases, such as lumbar stenosis, spondylolisthesis, lumbar instability, spinal deformity, and tumor. Pedicle screw (PS) fixation was first introduced by Bouche and has been adopted as the gold standard for posterior lumbar fusion. Santoni and colleagues introduced a new methodological screw insertion technique that uses a cortical bone trajectory (CBT), described as that from a medial to lateral path in the transverse axial plane and caudal to the cephalad path in the sagittal plane through the pedicle for maximum contact of the screw with the cortical bone. Owing to the lower invasiveness, superior cortical bone contact, and reduced neurovascular injury incidence, the CBT technique has been widely used in posterior lumbar fusion; however, these advantages have not been proven in clinical/radiological and biomechanical studies. We designed the present study to review the existing evidence and evaluate the merit of CBT screw fixation. Six electronic databases were searched for relevant articles published in August 2020 using the search terms “cortical bone trajectory,” “CBT spine,” “CBT fixation,” “cortical pedicle screws,” and “cortical screws.” Studies were analyzed and divided into the following groups: “biomechanics investigation,” “surgical technique,” and “clinical/radiological studies.” Most studies compared CBT and PS fixation, and the CBT screw fixation method showed better or similar outcomes.

Biomechanical comparison of single-bundle versus double-bundle anterior cruciate ligament reconstruction: a meta-analysis

Methods@#The electronic databases MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched for relevant articles comparing the outcomes of SB-ACLR versus DB-ACLR that were published until November 2019. @*Results@#Seventeen biomechanical studies were included. The anterior laxity measured using the anterior drawer test showed significantly better results in DB-ACLR when compared with SB-ACLR. In addition, outcomes of the anterior tibial translation test under a simulated pivot shift presented with better results at low flexion and 30° in DB-ACLR, compared with SB-ACLR. However, there were no significant biomechanical differences between the groups in internal rotation. @*Conclusions@#The present study demonstrated that both techniques for ACLR are associated with restoration of normal knee kinematics. DB-ACLR is superior to SB-ACLR in terms of restoration of anteroposterior stability.However, which technique yields better improvement in internal rotation laxity, and internal rotation laxity under a simulated pivot shift at a specific angle, remains unclear.Level of evidence: This is a level II meta-analysis.

The Importance of Early Surgical Decompression for Acute Traumatic Spinal Cord Injury

BACKGROUND: Traumatic spinal cord injury (SCI) is a tragic event that has a major impact on individuals and society as well as the healthcare system. The purpose of this study was to investigate the strength of association between surgical treatment timing and neurological improvement. METHODS: Fifty-six patients with neurological impairment due to traumatic SCI were included in this study. From January 2013 to June 2017, all their medical records were reviewed. Initially, to identify the factors affecting the recovery of neurological deficit after an acute SCI, we performed univariate logistic regression analyses for various variables. Then, we performed a multivariate logistic regression analysis for variables that showed a p-value of < 0.2 in the univariate analyses. The Hosmer-Lemeshow test was used to determine the goodness of fit for the multivariate logistic regression model. RESULTS: In the univariate analysis on the strength of associations between various factors and neurological improvement, the following factors had a p-value of < 0.2: surgical timing (early, < 8 hours; late, 8–24 hours; p = 0.033), completeness of SCI (complete/incomplete; p = 0.033), and smoking (p = 0.095). In the multivariate analysis, only two variables were significant: surgical timing (odds ratio [OR], 0.128; p = 0.004) and completeness of SCI (OR, 9.611; p = 0.009). CONCLUSIONS: Early surgical decompression within 8 hours after traumatic SCI appeared to improve neurological recovery. Furthermore, incomplete SCI was more closely related to favorable neurological improvement than complete SCI. Therefore, we recommend early decompression as an effective treatment for traumatic SCI.

A Comparison of Results after Anterior Cruciate Ligament Reconstruction in over 40 and under 40 Years of Age: A Meta-Analysis

PURPOSE: Anterior cruciate ligament (ACL) injury is one of the most common injuries that occur in the knee, and ACL reconstruction (ACLR) is commonly performed for preventing aggravation of degenerative changes and restoring of knee stability in young, athletic patients. This metaanalysis has a purpose of evaluating the clinical and arthrometrical outcomes of ACLR in a group of middle age patients (40 years and older) and comparing with patients under 40 years of age. METHODS: MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Web of Science, and SCOPUS electronic databases were searched for relevant articles comparing the outcomes of ACLR between younger and older than 40 years of age until December 2016. Data searching, extraction, analysis, and quality assessment were performed based on the Cochrane Collaboration guidelines. Clinical outcomes were evaluated and compared between groups. The results were presented as mean difference for continuous outcomes with 95% confidence intervals whereas risk ratio for binary outcomes. RESULTS: Seven studies were included in the meta-analysis. Based on International Knee Documentation Committee classification, side-to-side difference, Tegner activity score, Lysholm knee score, there were no significant clinical and mechanical differences between the groups. CONCLUSIONS: This meta-analysis confirmed that after ACLR, middle age (>40 years) and young age (<40 years) patients did not present with significant difference in clinical and arthrometric results.

Effect of oleanolic acid on the activity, secretion and gene expression of matrix metalloproteinase-3 in articular chondrocytes in vitro and the production of matrix metalloproteinase-3 in vivo

In the present study, we tried to examine whether oleanolic acid regulates the activity, secretion and gene expression of matrix metalloproteinase-3 (MMP-3) in primary cultured rabbit articular chondrocytes, as well as the production of MMP-3 in the knee joint of rat to evaluate the potential chondroprotective effect of oleanolic acid. Rabbit articular chondrocytes were cultured in a monolayer, and reverse transcription-polymerase chain reaction (RT-PCR) was used to measure interleukin-1β (IL-1β)-induced gene expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), ADAMTS-5 and type II collagen. In rabbit articular chondrocytes, the effects of oleanolic acid on IL-1β-induced secretion and proteolytic activity of MMP-3 were investigated using western blot analysis and casein zymography, respectively. The effect of oleanolic acid on in vivo MMP-3 protein production was also examined, after intra-articular injection to the knee joint of rat. The results were as follows: (1) oleanolic acid inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5, but increased the gene expression of type II collagen; (2) oleanolic acid reduced the secretion and proteolytic activity of MMP-3; (3) oleanolic acid suppressed the production of MMP-3 protein in vivo. These results suggest that oleanolic acid can regulate the activity, secretion and gene expression of MMP-3, by directly acting on articular chondrocytes.

Epidural Lymphoma Mimicking Hematoma: A Case Report

STUDY DESIGN: Case report. OBJECTIVES: To present a rare case of a spinal epidural lymphoma mimicking a hematoma. SUMMARY OF LITERATURE REVIEW: The incidence of extranodal invasion of lymphoma is very low, and spinal compression as a clinical symptom rarely occurs in extranodal lymphoma. MATERIALS AND METHODS: A 37-year-old woman who complained of neck pain that had lasted for the past 3 months with no underlying disease visited the hospital and was treated conservatively with medication and physical therapy. Even though the patient was given an epidural injection 1 month prior to visiting our hospital, the pain lingered and the cervical myelopathy became aggravated, so the patient was initially diagnosed with epidural hematoma. This predisposed the patient to treatment strategies such as laminectomy and fusion, but the patient was ultimately diagnosed with non-Hodgkin lymphoma. RESULTS: The patient underwent a laminectomy with excision of the lesion and fusion. The patient was diagnosed with non-Hodgkin lymphoma as a result of this, and the patient's radicular pain and numbness improved immediately following surgery, except for mild weakness in both hands. CONCLUSIONS: Although spinal epidural lymphoma is similar to hematoma, and is a very rare disease, surgeons should take it into consideration in the differential diagnosis of patients with a spinal epidural lesion.

Donor Specific Transfusion 24 Hours Prior to(-24h DST) Living Donor Renal Transplantation / 대한신장학회잡지

The goal of the immunologic maneuvering for organ transplantation may be the donor specific immune tolerance rather than non-specific immunosuppression. Although DST is one of the most extensively studied methods for donor specific immune hyporesponsiveness, it is not widely used in recent years because of possible sensitization and overall improvement of graft survival without DST. Several human and animal studies showed that -24h DST with concomitant cyclosporine administration improved graft survival. -24 DST may not induce adverse sensitization that preclude subsequent transplantation and the procedure is simple and does not delay the operation in living donor transplantation. Between Feb. 1994 and Jan. 1997, 33 patients received 100-200ml of fresh whole blood from the kidney donor 1 day before transplantation. Twenty donors were living related and 13 donors were non- related. Mean age was 40(22-52). Two patients was diabetic. All but one received primary allograft. Cyclosporine and prednisolone were the primary immunosuppressants that started 2-3 days before transplantation. Acute rejection occurred in 11 recipients(33.3%). Acute rejection tended to occur earlier. Eight of 11 first episodes were within 3 days post- transplant, which were all recovered by either steroid pulse or OKT3. Mean follow up was 35 months. Two patients died with functioning graft. Three-year graft survival rate was 93.9%. There was no immunologic graft loss. We conclude that -24h DST may be a valuable option of immune modulation for renal transplantation with no demonstrable adverse reaction. It's beneficial effect needs to be confirmed by a larger controlled study.