A Novel Method of Making Hinges Using a Newly Designed Sharp Rongeur to Enhance Radiological and Clinical Outcomes in French‐Door Cervical Expansive Laminoplasty

ObjectiveAlthough the lamina open angle of making hinges is closely related to the outcomes of French‐door laminoplasty (FDL) for treatment of cervical spondylosis, there have been no methods to predict the lamina open angle preoperatively as yet. The aim of this study was to investigate the accuracy of predicting the laminal open angle using our newly designed sharp rongeur, and to compare the postoperative outcomes and complications between the methods of making hinges using the newly designed sharp rongeur and the traditional high‐speed micro‐drill during the FDL.MethodsThis was a single‐center retrospective study. Following the approval of the institutional ethics committee, a total of 39 patients (Male: 28; Female: 11) diagnosed with cervical spondylos who underwent FDL in our institution between January 2018 and May 2019 were enrolled. Patients were divided into two groups based on the method of making hinges (sharp rongeur: 22 cases; high‐speed micro‐drill: 17 cases). The average age at surgery was 59.1 years (range: 16–85 years). The radiological parameters, clinical outcomes, modified Japanese Orthopaedic Association (mJOA) scale score, and the recovery rate of mJOA were recorded and compared between the groups, respectively. The radiological parameters and clinical measurements at pre‐ and post‐operation stages were compared using the paired‐sample t‐test, the Wilcoxon signed‐rank test, and the Friedman''s test, and variables in the two groups were analyzed using an unpaired Student''s t‐test or a Mann–Whitney U test.ResultsThe average follow‐up period was 20.4 months (range: 14.0–25.9 months), the postoperative open angle was 60.13° ± 3.69° in the rongeur group with 22.78° ± 4.34° of angular enlargement, which was significantly lower than that of 68.96° ± 1.00° in the micro‐drill group with 32.75° ± 4.22° of angular enlargement (U = 19.000, p < 0.001). The rongeur group showed a higher fusion rate (34.1% vs 14.7%, χ ² = 11.340, p = 0.001), and a lower fracture rate of the lamina (7.8% vs 25.5%, χ ² = 14.185, p < 0.001) at 1‐month post‐surgery, compared to the micro‐drill group. There were no significant differences in the clinical outcomes and postoperative complications between the two groups (p > 0.05), except in the recovery rate of mJOA scores (0.836 ± 0.138 vs 0.724 ± 0.180, U = 115.000, p = 0.042) and neck disability index (NDI) at the final follow‐up (7.55 ± 10.65 vs 14.71 ± 8.72, U = 94.000, p = 0.008).ConclusionsThe special sharp rongeur with a tip angle of 20° could be a preferred method to make hinges during FDL, which can predict the laminal open angle accurately and enlarge it to about 23°, thus reducing the fracture rate and accelerating the bony fusion of hinges compared with the outcomes of the traditional micro‐drill method.     

Anterior Cervical Discectomy and Fusion Combined with Foraminotomy Assisted by High‐Definition 3‐Dimensional Exoscope in the Treatment of Cervical Spondylotic Radiculopathy Secondary to Bony Foraminal Stenosis

ObjectiveTo evaluate the outcomes of cervical spondylotic radiculopathy secondary to bony foraminal stenosis treated with anterior cervical discectomy and fusion (ACDF) combined with anterior cervical foraminotomy (ACF) assisted by High‐Definition 3‐Dimensional Exoscope.MethodsIn this retrospective study, a total of 19 consecutive patients (12 males and seven females, with an average of 49.2 years, range from 40 to 59 years) with spondylotic radiculopathy caused by bony foraminal stenosis underwent ACDF combined with ACF assisted by High‐Definition 3‐Dimensional Exoscope in our hospital between January 2019 and December 2019 were included in this study. All patients signed the consent form before the surgery. The patient baseline information such as gender, age, body mass index (BMI), surgery time, blood loss, hospital stay, lesion segment, side, follow‐up time and postoperative complications were recorded. The Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analogue Scale (VAS) were measured and compared before surgery, 1 months and final follow‐up after surgery. The radiographic outcomes were evaluated using the C₂‐C₇ angel, disc height, foraminal height, superior diagonal distance, inferior diagonal distance, and foraminal area.ResultsThe involved levels included C₄‐C₅ (six cases), C₅‐C₆ (10 cases), C₆‐C₇ (three cases). The mean duration of the surgery, mean blood loss, mean hospital stay, and mean follow‐up were 100 ± 11.10 min, 19.4 ± 7.05 mL, 7.1 ± 0.99 days, and 12.1 ± 2.25 months, respectively. The average preoperative JOA score was 11.9 ± 1.31, then improved to 15.7 ± 0.73 (t = −13.45, P < 0.001) and 16.2 ± 0.74 (t = −14.39, P < 0.001) at 1 month after operation and at last follow‐up, respectively. The average preoperative NDI score was 27.3 ± 3.36, then decreased to 5.1 ± 1.79 (t = 20.63, P < 0.001) and 4.5 ± 1.21 (t = 25.53, P < 0.001) 1 month after operation and at last follow‐up, respectively. The average preoperative VAS score was 6.7 ± 0.93, then decreased to 2.4 ± 0.69 (t = 15.05, P < 0.001) and 1.9 ± 0.78 (t = 16.40, P < 0.001) 1 month after operation and at last follow‐up, respectively. As compared with the condition before surgery, there was a significant improvement in the C₂‐C₇ angel, disc height, foraminal height, and foraminal area (P < 0.05). None of the patients developed postoperative vascular injury, nerve injury, loosening and rupture of the internal fixation, displacement of interbody fusion cage, and pseudarthrosis.ConclusionACDF combined with ACF assisted by High‐Definition 3‐Dimensional Exoscope is effective and safe for the treatment of CSR caused by secondary to bony foraminal stenosis.     

Surgical Treatment for Severe Cervical Hyperlordosis and Thoracolumar Kyphoscoliosis with Emery–Dreifuss Muscular Dystrophy: A Case Report and Literature Review

BackgroundEmery–Dreifuss muscular dystrophy (EDMD) is an uncommon, gradually progressive X‐linked myopathy, and it could result in rigid spinal deformity. Only a few case reports have described surgical treatment of cervical hyperlordosis and thoracolumbar kyphoscoliosis secondary to EDMD. We report a rare case of EDMD to present the surgical strategies of severe cervical hyperlordosis and thoracolumbar kyphoscoliosis.Case presentationThe patient was a 22‐year‐old man with EDMD who had severe cervical hyperlordosis and thoracolumbar kyphoscoliosis. A posterior spinal fusion from T9‐S2 was performed to correct the thoracolumbar kyphoscoliosis at the age of 21 years. Six months later, with an anterior C7‐T1 closing wedge bone‐disc‐bone osteotomy and a posterior–anterior–posterior cervicothoracic fusion from C4‐T4, the cervical deformity was corrected, thus achieving a horizontal gaze. During 1.5‐year follow‐up, no loss of correction was observed.ConclusionCervical posterior–anterior–posterior closing‐wedge osteotomy combined with long fusion at thoracolumbar spine can be a reliable surgical technique to correct severe spine deformity in EDMD. This two‐stage revision surgical strategy can help restore a horizontal gaze on the basis of a balanced trunk. Cervical deformity in such patients should be corrected in the first stage considering its role as a “driver” of the global spine deformity.     

Comparison of Outcomes After Total Knee Arthroplasty Involving Postoperative Neutral or Residual Mild Varus Alignment: A Systematic Review and Meta‐analysis

Comparing mainly clinical and functional outcomes as well as prosthesis survival with neutral and residual mild varus alignment, we searched PubMed, Embase, Cochrane Library and Web of Science databases from 1 January 1974 to 18 December 2020 to identify studies comparing clinical and functional outcomes as well as prosthesis survival in the presence of different alignments after total knee arthroplasty (TKA) for varus knees. The included studies were assessed by two researchers according to the Newcastle–Ottawa Scale (NOS). Postoperative neutral alignment (0° ± 3°) was compared to residual mild varus (3°–6°) and residual severe varus (>6°). Meta‐analysis was performed using Review Manager 5.3. The odds ratios (OR) and mean differences (MD) were used to compare dichotomous and continuous variables. The fixed‐effect model and random‐effect model were used to meta‐analyze the data. Nine studies were included in the meta‐analysis with 1410 cases of postoperative neutral alignment, 564 of residual mild varus alignment and 175 of residual severe varus alignment following TKA, all of which were published after 2013. Three studies scored 7 points on the NOS, while the remaining studies scored 8 points, suggesting high quality. The pooled mean differences (MDs) of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score were 1.07 [95% confidence interval (CI) −1.06 to 3.20; P = 0.32; I ² = 79%]. The meta‐analysis showed that neutral alignment and mild varus alignment were associated with similar the Oxford Knee Score (OKS), Knee Society Knee Score (KS‐KS), and Knee Society Function Score (KS‐FS), while neutral alignment was associated with lower Forgotten Joint Score (FJS) [mean difference −6.0, 95% confidence interval (CI) −9.37 to −2.64, P = 0.0005]. Neutral alignment was associated with higher KS‐KS than severe alignment (M 2.98, 95% CI 1.42 to 4.55, P = 0.0002; I ² = 0%) as well as higher KS‐FS (M 8.20, 95% CI 4.58 to 11.82, P < 0.00001; I ² = 0%). Neutral alignment was associated with similar rate of survival as mild varus alignment (95% CI 0.36 to 9.10; P = 0.48; I ² = 65%) or severe varus alignment (95% CI 0.94 to 37.90; P = 0.06; I ² = 61%). There was no statistical difference in others. Residual mild varus alignment after TKA may lead to similar or superior outcomes than neutral alignment in patients with preoperative varus knees, yet the available evidence appears to be insufficient to replace the current gold standard of neutral alignment. Severe varus alignment should be avoided.     

Evaluation of Serum 25‐Hydroxyvitamin D3 and Bone Mineral Density in 268 Patients with Hip Fractures

ObjectiveThe aim of the present study was to evaluate the relationship among vitamin D nutritional status, bone mineral density, and other factors in elderly patients with brittle hip fractures.MethodsThe present study was a retrospective analysis of 268 patients, 102 men (38.06%) and 166 women (61.94%), with brittle hip fractures admitted to the Hip Joint Center of Tianjin Hospital from February 2016 to June 2018. The median age of the patients was 74 years (range, 50–93 years). The patients were divided into three groups based on age: ≤69 years, 70–79 years, and ≥80 years. Serum 25‐hydroxyvitamin D₃ (25(OH) D₃), parathyroid hormone (PTH), body mass index (BMI), and bone mineral density (BMD) of the lumbar spine, femoral neck, and hip were measured and statistically analyzed.ResultsThe median serum 25(OH)D₃ level of patients was 9.90 (range, 2.60–42.70) ng/mL; the proportion of deficiency was 89.18% and the deficiency was severe in 136 cases (49.25%). The proportion of vitamin D deficiency was significantly lower in men than in women (P = 0.013). With the increase of age, 25(OH)D₃ levels gradually decreased (P = 0.044) and PTH levels gradually increased (P < 0.001). There was significantly negative correlation (P < 0.001) between the levels of serum 25(OH)D₃ and PTH. There were 200 cases (74.63%) in which T‐values of BMD were less than −2.5 in any part of the lumbar vertebrae, femoral neck, and hip. T‐values in 74 cases (27.61%) were less than −2.5 in all three parts. The T‐values of BMD in men were significantly higher than those in men (P < 0.001). With the increase of age, the femoral neck BMD in men gradually decreased (P = 0.016), and the femoral neck and hip BMD in female gradually decreased (P‐value was 0.001 and 0.003, respectively). Multivariate analysis suggested that gender and BMI were independent risk factors for BMD, and vitamin D deficiency affected BMD.ConclusionVitamin D deficiency is common in patients with brittle hip fractures, especially in women. With the increase of age, vitamin D continues to decrease and PTH increases. The decrease of BMD in patients with hip fractures is the result of a combination of age, gender, BMI, and vitamin D content.     

Non‐Anatomical Arthroscopic All‐Inside Repair of Medial Meniscus Posterior Root Tear to Posterior Cruciate Ligament for Patients with Normal Lower Limb Alignment

ObjectiveTo describe a non‐anatomical arthroscopic all‐inside repair of medial meniscus posterior root tear (MMPRT) to posterior cruciate ligament (PCL) technique for patients with normal lower limb alignment and to evaluate the short‐term clinical and radiologic outcomes.MethodsMMPRT directly to PCL was repaired with all‐inside horizontal mattress suturing technique rather than by the transtibial pullout suture technique or anchor suturing repair technique in 20 Laparade Type II MMPRT patients with normal lower limb alignment during 2018–2019. The clinical and radiological outcomes were evaluated retrospectively for at least 2 years follow‐up. The VAS score, Lysholm score, Tegner activity score were evaluated preoperatively and at the final follow‐up. The status of the medial meniscus posterior root were assessed on magnetic resonance imaging (MRI) preoperatively and at the final follow‐up.ResultsTwenty patients (mean age 54.5 ± 19.5 years) were included in the present study. The mean follow‐up duration was 32.5 ± 5.8 months. The VAS score was significantly decreased from preoperative 6.5 ± 1.5 to 2.1 ± 1.4 at the final follow‐up (P < 0.01). The mean Lysholm score was significantly improved from 43.7 ± 10.9 preoperatively to 85.7 ± 10.8 (P < 0.01). The median Tegner activity score was improved from 1.0 (range 1–4) to 3.0 (range 2–4, P < 0.01). On MRI, a total of 12 cases (60%) had complete healing, while eight cases (40%) had partial healing.ConclusionNon‐anatomical arthroscopic all‐inside repair of MMPRT to PCL may yield beneficial clinical outcomes and a higher rate of clinical healing in Type II MMPRT patients with normal lower limb alignment. It is an easy and reliable alternative technique to the transtibial pullout suture or anchor suture repair technique.     

Protection of Icariin Against Hydrogen Peroxide‐Induced MC3T3‐E1 Cell Oxidative Damage

ObjectiveThe aim of the present study was to evaluate the potential protective mechanism of icariin against oxidative damage caused by hydrogen peroxide in MC3T3‐E1 cells.MethodsMC3T3‐E1 cells were treated with different concentrations of icariin to explore the optimal dose of icariin. MC3T3‐E1 cells were divided into groups treated with various concentrations of hydrogen peroxide (H₂O₂; 0, 0.1, 0.2, 0.5, 1, and 2 mM) for 24 h to induce oxidative damage and cell viability was assessed by Cell Counting Kit‐8 (CCK‐8) assay. Then, cells were divided into five groups: control, H₂O₂ (0.2 mM), icariin (0.1 μM) and H₂O₂ (0.2 mM), + icariin (0.1 μM). Cell viability was detected by CCK‐8 assay. In addition, the content of glutathione and superoxide dismutase and the activity level of malondialdehyde in these treatment groups were determined. Alkaline phosphatase (ALP) and alizarin red S (ARS) staining were also performed to measure the early and late osteogenesis, respectively. Protein expression of β‐catenin and cyclin D1 was measured by western blot assay. Then, we used an antagonist of Wnt/β‐catenin signaling pathway (DKK‐1) and western blot analysis to further explore potential mechanism.ResultsAfter 24 h of exposure to 0.2 mM H₂O₂, the viability of MC3T3‐E1 cells was significantly decreased compared to that of the control cells. We first found that icariin can promote cell proliferation of MC3T3‐E1 cells in a dose‐dependent manner, with the dosage 0.1 μM showing the best pro‐proliferative effect. Furthermore, icariin could promote the protein expression of OSX and RUNX2. The results showed that icariin can reverse the inhibitory osteogenic effects of MC3T3‐E1 caused by H₂O₂. In addition, icariin could increase the Wnt‐signaling related proteins. The results showed that MC3T3‐E1 cells in the H₂O₂ (0.2 mM) + icariin (0.1 μM) + Wnt‐signaling antagonist (DKK‐1) group had weaker ALP and ARS staining compared with that observed in the control and H₂O₂ (0.2 mM) + icariin (0.1 μM) groups. The ALP activity and calcium content were decreased in the 0.2 mM H₂O₂ + 0.1 μM icariin + DKK‐1 group compared to that observed in the 0.2 mM H₂O₂ + 0.1 μM icariin group.ConclusionThe results showed that icariin can increase the viability of MC3T3‐E1 cells, reverse the oxidative stress induced by H₂O₂ and protect MC3T3‐E1 cells against H₂O₂‐induced inhibition of osteogenic differentiation, which may occur through the Wnt/β‐catenin signaling pathway.     

Freehand S2‐Alar‐Iliac Screw Placement Technique in Lumbosacral Spinal Tumors: A Preliminary Study

ObjectiveS2‐alar‐iliac (S2AI) screw technique is widely used in spinal surgery, but it is rarely seen in the field of spinal tumors. The aim of the study is to report the preliminary outcomes of the freehand S2AI screw fixation after lumbosaral tumor resection.MethodsThe records of patients with lumbosacral tumor who underwent S2AI screw fixation between November 2016 to November 2020 at our center were reviewed retrospectively. Outcome measures included operative time, blood loss, complications, accuracy of screws, screw breach, and overall survival. Mean ± standard deviation or range was used to present continuous variables. Kaplan–Meier curve was used to present postoperative survival.ResultsA total of 23 patients were identified in this study, including 12 males and 11 females, with an average age of 47.3 ± 14.5 (range,15–73). The mean operation time was 224.6 ± 54.1 (range, 155–370 min). The average estimated blood loss was 1560.9 ± 887.0 (600–4000 ml). A total of 46 S2AI screws were implanted by freehand technique. CT scans showed three (6.5%) screws had penetrated the iliac cortex, indicating 93.5% implantation accuracy rate. No complications of iatrogenic neurovascular or visceral structure were observed. The average follow‐up time was 31.6 ± 15.3 months (range, 13–60 months). Two patients'' postoperative plain radiography showed lucent zone around the screw. One patient underwent reoperation for wound delayed infection. At the latest follow‐up, eight patients had tumor‐free survival, 11 had survival with tumor, and four died of disease.ConclusionThe freehand S2AI screw technique is reproducible, safe, and reliable in the management of lumbosacral spinal tumors.     

Expansion of Spinal Canal with Lift‐Open Laminoplasty: A New Method for Compression Cervical Myelopathy

ObjectiveThis study is to introduce lift‐open laminoplasty and verify the increase of the spinal canal area following this surgical technique according to the preoperative anatomical measurement.MethodsThere are 82 patients (43 male and 39 female) analyzed in our study from January 2019 to December 2020. The average age was 63.2 ± 3.21 years (from 41 to 84 years). All of them were treated with open‐door laminoplasty, with a decompression segment range from C3 to C6. The increase of the spinal canal area after open‐door laminoplasty was measured on postoperative CT images of the patients, and the distances between both lamina‐facet junctions and lamina length was measured on preoperative CT images. Using the Pythagorean theorem for the equation of calculation area after the expansile open‐door laminoplasty. Based on previous measurement parameters, spinous process length, lateral mass width, distance between osteotomy line and lamina‐facet junctions line were additionally measured on preoperative CT images. Pythagorean theorem was used for calculating the area after the expansile lift‐open laminoplasty. The results were recorded and a statistical analysis was undertaken. Then, there were six patients (five male and one female) treated with lift‐open laminoplasty on C6, open‐door on C3–C5, who suffer from cervical spondylotic myelopathy from December 2020 to January 2021. The average age was 60.3 ± 1.7 years (from 56 to 71 years). Operation time, blood loss, and Japanese Orthopaedic Association (JOA) score recovery rate were recorded. Intraoperative and postoperative complications were observed.ResultsThe increase of the spinal canal area after open‐door laminoplasty measured on postoperative CT images was 123.01 ± 17.06 mm² and the calculation of the increase of the spinal canal areausing the Pythagorean theorem after open‐door laminoplasty was 122.86 ± 15.86 mm². A comparison of the actual value with calculative value showed no significant difference (T value = 0.057, P value = 0.955). The calculation of the increase of the spinal canal area after lift‐open laminoplasty was 183.57 ± 62.99 mm², which was larger than that after open‐door laminoplasty (T value = 8.462, P value < 0.001). Mean operation time was 153.3 min and operative blood loss was 600 mL of the six patients treated with lift‐open laminoplasty. At 1 month follow‐up, all patients had recovered well. JOA score recovery rate was 37.6% and no intraoperative and postoperative complications occurred.ConclusionLift‐open laminoplasty could preserve nearly 100% of extensor muscle, avoid damaging C7 paraspinal muscles and C6‐7 posterior muscle‐ligament complex, reconstruct the spinous process firmly in the midline, and expand adequate spinal canal area after operation. These advantages could reduce the incidence rate of complications and bring better clinical results than traditional laminoplasty.     

Pavlov's Ratio of the Cervical Spine in a Korean Population: A Comparative Study by Age in Patients with Minor Trauma without Neurologic Symptoms

BackgroudThere are many studies on the vertebral body-to-canal ratio, the so-called Pavlov''s ratio of the cervical spine. However, there are no studies on its relation with age to clarify each bony component''s contribution to the spinal canal formation and its size. The aim of this study was to investigate differences and changes in the vertebral body-to-canal ratio according to age in an asymptomatic population.MethodsThis is a cross-sectional study of 280 asymptomatic individuals. A total of 140 men and 140 women representing each decade of life from the first to the seventh were included in this study. The anteroposterior length of the vertebral body and canal from C3 to C6 was measured on sagittal radiographs to calculate the vertebral body-to-canal ratio.ResultsThe average Pavlov''s ratio was significantly larger (p < 0.001) in the first decade of life. The average Pavlov''s ratio of the individuals in the first decade of life was 1.09 between C3 and C6 (1.08 at C3, 1.07 at C4, 1.11 at C5, and 1.13 at C6; range, 0.78–1.51). There was no significant difference among the other decades of life.ConclusionsWe assessed the Pavlov''s ratio of the cervical spine in an asymptomatic population. It is our belief that the spinal canal size is the largest in the first decade of life, and the Pavlov''s ratio becomes almost fixed throughout life after maturity.     

Involvement of Peripheral Adenosine A2 Receptors in Adenosine A1 Receptor-Mediated Recovery of Respiratory Motor Function After Upper Cervical Spinal Cord Hemisection

Abstract

Background/Objective: In an animal model of spinal cord injury, a latent respiratory motor pathway can be pharmacologically activated through central adenosine A₁ receptor antagonism to restore respiratory function after cervical (C2) spinal cord hemisection that paralyzes the hemidiaphragm ipsilateral to injury. Although respiration is modulated by central and peripheral mechanisms, putative involvement of peripheral adenosine A₂ receptors in functional recovery in our model is untested. The objective of this study was to assess the effects of peripherally located adenosine A₂ receptors on recovery of respiratory function after cervical (C2) spinal cord hemisection.

Methods: Respiratory activity was electrophysiologically assessed (under standardized recording conditions) in C2-hemisected adult rats with the carotid bodies intact (H-CBI; n = 12) or excised (H-CBE; n = 12). Animals were administered the adenosine A2 receptor agonist, CGS-21680, followed by the A1 receptor antagonist, 1, 3-dipropyl-8-cyclopentylxanthine (DPCPX), or administered DPCPX alone. Recovered respiratory activity, characterized as drug-induced activity in the previously quiescent left phrenic nerve of C2-hemisected animals in H-CBI and H-CBE rats, was compared. Recovered respiratory activity was calculated by dividing drug-induced activity in the left phrenic nerve by activity in the right phrenic nerve.

Results: Administration of CGS-21680 before DPCPX (n = 6) in H-CBI rats induced a significantly greater recovery (58.5 ± 3.6%) than when DPCPX (42.6 ± 4.6%) was administered (n = 6) alone. In H-CBE rats, prior administration of CGS-21680 (n = 6) did not enhance recovery over that induced by DPCPX (n = 6) alone. Recovery in H-CBE rats amounted to 39.7 ± 3.7% and 38.4 + 4.2%, respectively.

Conclusions: Our results suggest that adenosine A2 receptors located in the carotid bodies can enhance the magnitude of adenosine A1 receptor-mediated recovery of respiratory function after C2 hemisection. We conclude that a novel approach of targeting peripheral and central adenosine receptors can be therapeutically beneficial in alleviating compromised respiratory function after cervical spinal cord injury.     

Risk Factors for Dysphagia after Anterior Cervical Discectomy and Fusion with the Zero‐P implant system: A Study with Minimum of 2 Years Follow‐up

ObjectiveTo evaluate the risk factors for dysphagia after anterior cervical discectomy and fusion (ACDF) with the Zero‐P Implant System by multidimensional analysis and investigated the predictive values of these risk factors for dysphagia.MethodsA retrospective analysis of 260 patients who underwent ACDF with the Zero‐P Implant System and had at least 2 year of follow‐up were performed. All patients were divided into a non‐dysphagia group and a dysphagia group. Sex, age, body mass index (BMI), intraoperative time, estimated blood loss, diabetes mellitus, hypertension, smoking, alcohol consumption, prevertebral soft‐tissue thickness, the levels of surgery, O‐C₂ angle, C_2–7 angle, T₁ slope and segmental angle were analyzed. The Modified Japanese Orthopaedic Association (JOA) scoring system was used to determine functional status. NDI was used to evaluate neck pain and disability. The Bazaz grading system was chosen to evaluate dysphagia after surgery. Postoperative cerebrospinal fluid (CSF) leakage, infection, and dysphagia were recorded in both groups. An independent t‐test was used to compare quantitative variables, a chi‐square test was used to compare qualitative data between the two groups. To eliminate the influence of confounding factors, logistic regression was performed for multifactor regression of factors. The results were regarded as significant when the P‐values were less than 0.05 in this study.ResultsIn total, the non‐dysphagia group comprised 70 patients and the dysphagia group comprised 190 patients, with an average age of 58.33 ± 4.68 years (ranging, 42–82 years). These patients were followed up for 28.5 ± 3.5 months (range, 24–32 months). For clinical outcomes, both groups demonstrated significant improvement in the NDI and JOA scores (P < 0.001). According to the Bazaz dysphagia grading system, mild, moderate, and severe dysphagia were found in 50, 17, and 3 patients, respectively. In total, 37.1% (n = 26) had resolved by 3 month, 38.6% (n = 27) by 6 months, and 17.1% (n = 12) by 12 months. Chi‐square test results indicated that number of operated levels, operation time dT1 slope, dO‐C₂ angle, dC_2–7 angle, segmental angle and dPSTT were associated with a high incidence of dysphagia. Multivariate logistic regression analysis showed that number of operated levels, operation time, dC_2–7 angle and dPSTT were significantly associated with postoperative dysphagia.ConclusionsMore operated levels, more operation time, more dC_2–7 angle and dPSTT were the risk factors for postoperative dysphagia. In additional, sufficient preoperative preparation, evaluation combined with proficient and precise surgical treatment were suggested to reduce the incidence of postoperative dysphagia when ACDF was performed.     

Differential expression of adenosine A1 and A2A receptors after upper cervical (C2) spinal cord hemisection in adult rats

BACKGROUND: In an animal model of spinal cord injury, a latent respiratory motor pathway can be pharmacologically activated via adenosine receptors to restore respiratory function after cervical (C2) spinal cord hemisection that paralyzes the hemidiaphragm ipsilateral to injury. Although spinal phrenic motoneurons immunopositive for adenosine receptors have been demonstrated (C3-C5), it is unclear if adenosine receptor protein levels are altered after C2 hemisection and theophylline administration. OBJECTIVE: To assess the effects of C2 spinal cord hemisection and theophylline administration on the expression of adenosine receptor proteins. METHODS: Adenosine A1 and A2A receptor protein levels were assessed in adult rats classified as (a) noninjured and theophylline treated, (b) C2 hemisected, (c) C2 hemisected and administered theophylline orally (3x daily) for 3 days only, and (d) C2 hemisected and administered theophylline (3x daily for 3 days) and assessed 12 days after drug administration. Assessment of A1 protein levels was carried out via immunohistochemistry and A2A protein levels by densitometry. RESULTS: Adenosine A1 protein levels decreased significantly (both ipsilateral and contralateral to injury) after C2 hemisection; however, the decrease was attenuated in hemisected and theophylline-treated animals. Attenuation in adenosine A1 receptor protein levels persisted when theophylline administration was stopped for 12 days prior to assessment. Adenosine A2A protein levels were unchanged by C2 hemisection; however, theophylline reduced the levels within the phrenic motoneurons. Furthermore, the decrease in A2A levels persisted 12 days after theophylline was withdrawn. CONCLUSION: Our findings suggest that theophylline mitigates the effects of C2 hemisection by attenuating the C2 hemisection-induced decrease in A1 protein levels. Furthermore, A2A protein levels are unaltered by C2 hemisection but decrease after continuous or interrupted theophylline administration. The effects on protein levels may underlie the stimulant actions of theophylline.     

Effects of Beraprost Sodium on Subjective Symptoms in Diabetic Patients with Peripheral Arterial Disease

Background

This study evaluated the effects of Beraprost sodium (Berasil) on subjective leg symptoms in patients with peripheral arterial disease caused by diabetes mellitus.

Methods

Ninety-four diabetic patients with peripheral arterial disease were treated with Beraprost in a fixed-dose, prospective, multicenter, cohort study. Beraprost (40 µg) was administered orally 3 times daily (120 µg/day) for 12 weeks. We developed a new disease-specific symptom questionnaire, which evaluated the effect of peripheral arterial disease on leg discomfort in daily life and assessed therapeutic responses to treatment. Patients were asked for their subjective assessment of symptoms on a written questionnaire before treatment and after 12 weeks of therapy.

Results

There was significant improvement in all estimated subjective symptoms (burning, coldness, edema, exertional pain, stabbing, and paresthesias) in the lower extremities at 12 weeks (p < 0.001). There were 18 patients with neuropathy in whom significant improvement was noted for 6 subjective symptoms at 12 weeks (p < 0.05). Adverse events considered to be drug-related were observed in 4 patients (4.3%), all of which were mild and resolved with discontinuation of the medication.

Conclusions

Beraprost is effective as a treatment for improving various subjective symptoms in the lower extremities, such as burning, coldness, edema, exertional pain, stabbing, and paresthesias, in diabetic patients with peripheral arterial disease.     

Early Clinical and Radiographic Outcomes of Robot‐Assisted Versus Conventional Manual Total Knee Arthroplasty: A Randomized Controlled Study

ObjectiveRobot‐assisted surgery has been promoted worldwide in recent years. The development of a domestic orthopaedic robot and its clinical application are therefore of great significance. This study aimed to compare the early clinical and radiographic outcomes of domestic robot‐assisted total knee arthroplasty (RA‐TKA) with conventional manual total knee arthroplasty (CM‐TKA).MethodsA total of 77 patients who underwent primary single‐sided TKA from June to December 2020 were prospectively enrolled; resulting in the inclusion of 72 patients. The patients were randomly divided into the RA‐TKA group (37 cases, with TKA being assisted by the Yuanhua Orthopaedic Robotic System) and the CM‐TKA group (35 cases, with TKA being performed using conventional tools). Knee function was evaluated by the knee range of motion (ROM), the American Knee Society Score (KSS), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Postoperative radiographic results were evaluated by full‐length weight‐bearing X‐rays of the lower limb and anteroposterior and lateral X‐rays of the knee were obtained preoperatively and at 90 days postoperative. The operative duration, blood loss, postoperative knee function, radiographic outcomes, and incidence of complications were compared by Student''s t‐test, Mann–Whitney U test, or chi‐square test. Serum levels of inflammatory markers before the operation and 1, 3, and 30 days after the operation were recorded and compared between the two groups.ResultsThe operation was significantly longer in the RA‐TKA group than in the CM‐TKA group (154.3 vs 115.2 min, p < 0.001). There was no significant difference in blood loss (933 vs 863 ml, p = 0.519) between the two groups. The knee ROM, KSS, and WOMAC were significantly improved in both groups 90 days after the operation compared with before the operation (p < 0.05), but there were no significant differences between the two groups (p > 0.05). The incidence of postoperative deep vein thrombosis was not statistically different between the two groups. In the radiographic findings at 90 days postoperatively we found the frequency of lateral tibial component (LTC) angle outliers was significantly lower in the RA‐TKA group (3.0% vs 29.4%, p = 0.003). The neutrophil‐to‐lymphocyte ratio (NLR) was significantly lower in the RA‐TKA group than in the CM‐TKA group on day 1 after surgery (9.9 vs 12.7, p = 0.024).ConclusionsRA‐TKA requires more time than CM‐TKA, which may be related to the learning curve and intraoperative registration. The short‐term postoperative knee functional outcomes had no differences between the two groups, and RA‐TKA improved the accuracy of tibial component alignment. Further follow‐up studies are required to investigate the long‐term outcomes.     

Ball Tip Technique for S2AI Screw Placement in Sacropelvic Fixation: A Comparative Study with Conventional Freehand Technique

ObjectiveTo evaluate the efficiency of the ball tip technique for S2AI screw placement and introduce this technique.MethodsSixty‐three patients who underwent pelvic fixation with S2AI screws were retrospectively reviewed. They were 29 males and 34 females with an average age of 59.6 ± 12.5 years. Among these patients, 35 patients (14 males and 21 females with an average age of 58.8 ± 11.3 years) received ball tip technique and 28 patients (15 males and 13 females with an average age of 63.7 ± 12.6 years) received conventional freehand technique. Ball tip technique was used in ball tip technique group. After a pedicle probe just penetrated the sacroiliac joint, a ball‐tipped probe consisting of a ball shaped metal tip with a flexible shaft was malleted to make a guide track within ilium. This ball‐tipped probe could bend automatically away from the cortex and forward through the cancellous bone when the tip met the cortical lamina of ilium, which can avoid penetration. After repeating the procedures, a guide hole was gradually formed. S2AI screw was inserted along the guide hole after tapping. In the conventional freehand group, S2AI screw was placed according to the conventional method. Postoperative computed tomography (CT) was used to assess the accuracy of screws. The time cost of screw insertion and screw‐related complications were recorded. Independent t‐test was used to compare the time cost between ball tip group and conventional freehand group. A chi‐square test was used to compare the accuracies of the ball tip group with the conventional group.ResultsThere were 35 patients (70 S2AI screws) in ball tip group and 28 patients (56 S2AI screws) in conventional freehand group. No screw‐related complication occurred in all patients. Time costs were 9.8 ± 4.5 mins in ball tip group and 20.2.0 + 8.6 mins in conventional freehand group, respectively (P < 0.05). Four screws penetrated iliac cortex in the ball tip group vs 10 screws in conventional freehand group (5.7% vs 17.9%) (P < 0.05).ConclusionsThe ball tip technique enhances the accuracy of screw placement and has less time cost compared with conventional freehand technique.     

The Permissive Safe Angle of the Tibial Tunnel in Transtibial Posterior Cruciate Ligament Reconstruction: A Three‐Dimensional Simulation Study

ObjectiveTo determine the permissive safe angle (PSA) of the tibial tunnel in transtibial posterior cruciate ligament (PCL) reconstruction based on a three‐dimensional (3D) simulation study.MethodsThis was a computer simulation study of transtibial PCL reconstruction using 3D knee models. CT images of 90 normal knee joints from 2017 to 2020 were collected in this study, and 3D knee models were established based on CT data. The tunnel approaches were subdivided into the anterior 1/3 of the anteromedial tibia (T1), middle 1/2 of the anteromedial tibia (T2), the tibial crest (T3), anterior 1/3 of the anterolateral tibia (T4), middle 1/2 of the anterolateral tibia (T5). Five tibial tunnels (T1–T5) were simulated on the 3D knee models. The PSAs, in different tibial tunnel approaches were measured, and subgroup analyses of sex, age and height were also carried out.ResultsThe mean PSAs of the tibial tunnels with 5 different approaches (T1–T5) were 58.49° ± 6.82°, 61.14° ± 6.69°, 56.12° ± 7.53°, 52.01° ± 8.89° and 49.90° ± 10.53°, respectively. The differences of the mean PSAs between the anteromedial and anterolateral approaches were significant (P < 0.05). However, there was no significant difference of the mean PSA value between the two anteromedial tibial tunnel approaches (T1–T2) (P > 0.05), as well as between the two anterolateral tibial tunnel approaches (T4–T5). The patient''s anthropomorphic characteristics of sex, age, and height were not associated with the PSAs.ConclusionsThe PSA varied with the anteromedial, tibial crest and anterolateral approaches for transtibial PCL reconstruction, and surgeons should limit the PCL drill guide by referring to the specific PSA for different surgical approaches.