Aging aggravates long-term renal ischemia-reperfusion injury in a rat model

Aim

Ischemia-reperfusion injury (IRI) has been considered as the major cause of acute kidney injury and can result in poor long-term graft function. Functional recovery after IRI is impaired in the elderly. In the present study, we aimed to compare kidney morphology, function, oxidative stress, inflammation, and development of renal fibrosis in young and aged rats after renal IRI.

Materials and methods

Rat models of warm renal IRI were established by clamping left pedicles for 45 min after right nephrectomy, then the clamp was removed, and kidneys were reperfused for up to 12 wk. Biochemical and histologic renal damage were assessed at 12 wk after reperfusion. The immunohistochemical staining of monocyte macrophage antigen-1 (ED-1) and transforming growth factor beta 1 (TGF-β1) and messenger RNA level of TGF-β1 in the kidney were analyzed.

Results

Renal IRI caused significant increases of malondialdehyde and 8-hydroxydeoxyguanosine levels and a decrease of superoxide dismutase activity in young and aged IRI rats; however, these changes were more obvious in the aged rats. IRI resulted in severe inflammation and tubulointerstitial fibrosis with decreased creatinine (Cr) clearance and increased histologic damage in aged rats compared with young rats. Moreover, we measured the ratio of Cr clearance between young and aged IRI rats. It demonstrated that aged IRI rats did have poor Cr clearance compared with the young IRI rats. ED-1 and TGF-β1 expression levels in the kidney were significantly higher in aged rats than in young rats after IRI.

Conclusion

Aged rats are more susceptible to IRI-induced renal failure, which may associate with the increased oxidative stress, increased histologic damage, and increased inflammation and tubulointerstitial fibrosis. Targeting oxidative stress and inflammatory response should improve the kidney recovery after IRI.     

Inhibitory effect of icariin on Ti-induced inflammatory osteoclastogenesis

Background

Wear particle-induced periprosthetic osteolysis that results in aseptic loosening is the most common cause of long-term failure after total joint replacement.

Materials and methods

Icariin (ICA), a flavonoid isolated from Epimedium pubescens, inhibits osteoclast formation, but its effects on wear particle-induced inflammatory osteoclastogenesis remains unclear. We investigated the role of ICA in the regulation of osteoclast differentiation in a murine macrophage cell line (RAW264.7), which is stimulated by titanium (Ti) particles and the receptor activator of NF-κB ligand.

Results

ICA effectively inhibited osteoclast formation and bone resorption in the differentiation medium. ICA (10⁻⁷ mol/L) significantly reduced the number of tartrate-resistant acid phosphatase-positive cells compared with the control, and significantly reduced the percentage of the surface covered by resorption lacunae. Quantitative real-time polymerase chain reaction analysis showed that ICA inhibited messenger RNA expression for the receptor activator of nuclear factor-κB, cathepsin K, tartrate-resistant acid phosphatase-positive, and matrix metalloproteinase-9 in RAW264.7 cells stimulated by Ti particles and receptor activator of NF-κB ligand. ICA also reduced pro-inflammatory cytokine expression of interleukin-1β and tumor necrosis factor-α in RAW264.7 cells cultured with Ti particles. In addition, incubation with cholecystokinin-8 showed that ICA had no toxic effects on RAW264.7 cells.

Conclusions

ICA possibly elicited inhibitory effects on inflammatory osteoclastogenesis induced by Ti particles, indicating that ICA may be useful for the prevention and treatment of wear particle-induced osteolysis.     

Open Arthrolysis for Chronic Elbow Dislocation with Extremely Severe Stiffness in Children

Objective

Studies on extremely severe elbow stiffness after chronic dislocation in children are scarce. This study aims to investigate the choice of surgical treatment modalities and to analyze their treatment efficacy in children with chronic elbow dislocation with extremely severe periarticular stiffness.

Methods

Data of 21 children with chronic elbow dislocation with extremely severe periarticular stiffness diagnosed and treated in our department between February 2015 and February 2021 were retrospectively analyzed. Twenty boys and one girl were included in the study, their mean age was 11 ± 2.5 years, and they had concomitant distal humerus fractures. For the treatment protocol, all children with extremely severe elbow stiffness were treated with open arthrolysis, and elbow joint stability was intraoperatively assessed. All children performed passive functional exercises the day after surgery. The elbow flexion and extension angles, range of motion (ROM), and Mayo score were evaluated preoperatively and at the final follow-up.

Results

Of the 21 children, only one had recurrent severe stiffness of the elbow joint after surgery; nevertheless, the function was still improved compared with that before surgery. Preoperatively, the mean elbow extension and flexion angles were 72.2° ± 12.7° and 93.6° ± 11.1°, respectively, and the range of motion (ROM) of the elbow joint was 17.8° ± 8.3°. At the final follow-up, the mean elbow extension and flexion angles were 22.7° ± 18.6° and 118.8° ± 15.4°, respectively, and the elbow joint ROM was 96.1° ± 17.4°. The differences in the preoperative and postoperative ROMs, flexion angles, and extension angles of the elbow joint were significant (p < 0.01). The MEPS at the final follow-up was 78.57 ± 14.24, which was significantly higher than preoperative (29.76 ± 10.89), and the excellent rate was 81%.

Conclusion

Open arthrolysis and open reduction and internal fixation of the elbow joint are effective in treating chronic elbow dislocation with extremely severe stiffness in children.     

The Fusion Rate of Cortical Bone Trajectory Screw Fixation and Pedicle Screw Fixations in L4-5 Interbody Fusion: A Retrospective Cohort Study

Objective

Although cortical bone trajectory (CBT) screw fixation has been used for several years, the number of studies on its fusion effects is limited. Furthermore, several studies report conflicting outcomes. We aimed to compare the fusion rates and clinical efficacy of CBT screw fixation and pedicle screw (PS) fixation for L4-L5 interbody fusion.

Methods

This study was a retrospective cohort control study. Patients with lumbar degenerative disease who underwent L4-L5 oblique lumbar interbody fusion (OLIF) or posterior decompression using CBT screws between February 2016 and February 2019 were included. Patients in whom PS was used were matched for age, sex, height, weight, and BMI. Record the operation time, blood loss. All enrolled patients underwent lumbar CT imaging at one-year follow-up to evaluate the fusion rate. At the two-year follow-up the visual analogue scale (VAS), Oswestry disability index (ODI), and Japanese Orthopaedic Association scores (JOA) were used to identify symptom improvement. Independent t-test was used for the comparison, and score data were analyzed using the χ² and exact probability tests.

Results

A total of 144 patients with were included. All patients were followed-up postoperatively for 25–36 months (average 32.42 ± 10.55 months). Twenty-eight patients underwent OLIF and CBT screw fixation, 36 underwent OLIF and PS fixation, 32 underwent posterior decompression and CBT screw fixation, and 48 underwent posterior decompression and PS fixation. The fusion rates following CBT screw and PS fixations in OLIF were 92.86% (26/28) and 91.67% (33/36), respectively (P = 1). The fusion rates following CBT screw and PS fixations in posterior decompression were 93.75% (30/32) and 93.75% (45/48), respectively (P > 0.05). Regardless of OLIF or posterior decompression, there were no significant differences in the VAS, ODI, and JOA scores between patients treated with CBT and PS (P > 0.05).

Conclusion

CBT screw fixation can achieve a satisfactory interbody fusion rate with a clinical efficacy similar to that of PS in patients with lumbar degenerative disease, regardless of whether OLIF or posterior decompression was performed.     

Detection of Common Anatomical Landmarks and Vertical Trajectories for Freehand Pedicle Screw Placement

Objective

It is clinically important for pedicle screws to be placed quickly and accurately. Misplacement of pedicle screws results in various complications. However, the incidence of complications varies greatly due to the different professional titles of physicians and surgical experience. Therefore, physicians must minimize pedicle screw dislocation. This study aims to compare the three nail placement methods in this study, and explore which method is the best for determining the anatomical landmarks and vertical trajectories.

Methods

This study involved 70 patients with moderate idiopathic scoliosis who had undergone deformity correction surgery between 2018 and 2021. Two spine surgeons used three techniques (preoperative computed tomography scan [CTS], visual inspection-X-freehand [XFH], and intraoperative detection [ID] of anatomical landmarks) to locate pedicle screws. The techniques used include visual inspection for 287 screws in 21 patients, preoperative planning for 346 screws in 26 patients, and intraoperative probing for 309 screws in 23 patients. Observers assessed screw conditions based on intraoperative CT scans (Grade A, B, C, D).

Results

There were no significant differences between the three groups in terms of age, sex, and degree of deformity. We found that 68.64% of screws in the XFH group, 67.63% in the CTS group, and 77.99% in the ID group were placed within the pedicle margins (grade A). On the other hand, 6.27% of screws in the XFH group, 4.33% in the CTS group, and 6.15% in the ID group were considered misplaced (grades C and D). The results show that the total amount of upper thoracic pedicle screws was fewer, meanwhile their placement accuracy was lower. The three methods used in this study had similar accuracy in intermediate physicians (P > 0.05). Compared with intermediate physicians, the placement accuracy of three techniques in senior physicians was higher. The intraoperative detection group was better than the other two groups in the good rate and accuracy of nail placement (P < 0.05).

Conclusion

Intraoperative common anatomical landmarks and vertical trajectories were beneficial to patients with moderate idiopathic scoliosis undergoing surgery. It is an optimal method for clinical application.     

Bone-to-Bone Ligament Preserving Laminoplasty with Ultrasonic Osteotome Assistance for Intraspinal Tumors: A Technical Note and Clinical Follow-Up

Objective

Laminectomy has been widely used for intraspinal tumor resection. However, the tilted spinous process and narrow lateral laminae of the thoracic spine along with the hypertrophic ligamentum flavum of the lumbar spine pose certain problems for the laminae removal of the traditional laminectomy. We improved the laminectomy method with ultrasonic osteotome to treat thoracolumbar tumors and assessed its safety and superiority.

Methods

A retrospective analysis was performed in 86 patients with thoracolumbar (T4–L5) spinal tumors treated by resection, including 44 with the lamina removed using the traditional method and 42 with the lamina removed using the bone-to-bone ligament preserving (BLP) laminoplasty, which preserves the posterior ligament complex. Age, sex, and tumor size, location, and depth were compared between the two groups. The length of incision and bone window, time to remove the vertebral lamina, and epidural effusion volume were recorded at 2 weeks after surgery in the two groups. Postoperative reexamination by magnetic resonance imaging (MRI) at 2 weeks and 3 months after surgery was compared with preoperative MRI to assess the change in vertebral lamina displacement.

Results

There were no statistical differences in age, sex, and tumor size, depth, or location between the two groups. The BLP laminectomy did not increase the risk of dural, spinal cord, or nerve injuries. The difference between the incision and tumor length, as well as the difference between the bone window and tumor length in the BLP laminectomy group, were smaller than those in the traditional laminectomy group, and the BLP laminectomy took less time compared to that of the traditional laminectomy (p < 0.05). There was no significant difference in the volume of epidural effusion between the two groups at 2 weeks postoperatively, or in the displacement of the returned vertebral plate observed in sagittal and axial positions. The same was true for the displacement at 3 months postoperatively in the axial position. However, the sagittal displacement in the BLP laminectomy group was smaller than that in the traditional laminectomy group (p < 0.05).

Conclusions

The BLP laminectomy is safe for the resection of thoracolumbar spinal canal tumors. It is less traumatic and faster, with less displacement of the returned lamina, resulting in a stable repair of the spine.     

A Comparison of Outcomes between the Wiltse Approach with Pedicle Screw Fixation and the Percutaneous Pedicle Screw Fixation for Multi-Segmental Thoracolumbar Fractures

Objective

Multi-segmental thoracolumbar fracture (MSF) generally refers to fractures occurring in two or more segments of the thoracolumbar spine. With the development of minimally invasive concept, there is little research on its application in the field of MSF. The purpose of this study is to compare two minimally invasive surgical techniques and determine which one is more suitable for treating patients with neurologically intact MSF.

Methods

We retrospectively analyzed the clinical data of 49 MSF patients with intact nerves who were admitted from January 2017 to February 2019. Among them, 25 cases underwent percutaneous pedicle screw fixation (PPSF), and 24 cases underwent Wiltse approach pedicle screw fixation (WAPSF). The operation time, number of fixed segments, blood loss, length of incision, postoperative ambulation time, accuracy of pedicle screw placement, facet joint violation (FJV), number of C-arm exposures, as well as pre- and postoperative visual analogue scale (VAS), Oswestry disability index (ODI), local Cobb's angle (LCA), and percentage of anterior vertebral body height (PAVBH) were recorded for both groups. Paired sample t-test was used for intra-group comparison before and after surgery while independent sample t-test was used for inter-group comparison.

Results

The differences in the number of fixed segments, intraoperative bleeding, postoperative bed time, accuracy rate of pedicle screw placement, VAS, and ODI between the two groups were not statistically significant (p > 0.05). However, the operative time and total surgical incision length were significantly shorter in the WAPSF group than in the PPSF group (p < 0.05), and the FJV was significantly higher in the PPSF group than in the WAPSF group (p < 0.05). Also, the PPSF group received more intraoperative fluoroscopy (p < 0.05). The result of LCA and PAVBH in the WAPSF group were significantly better than in the PPSF group (p < 0.05).

Conclusions

Both PPSF and WAPSF were found to be safe and effective in the treatment of MSF without neurological deficits through our study. However, considering radiation exposure, FJV, vertebral height restoration, correction of kyphosis, and learning curve, WAPSF may be a better choice for neurologically intact MSF.