颈椎脊神经沟及其沟内段脊神经形态学观察

目的　探讨脊神经沟与沟内段脊神经受嵌压的关系。方法　取 6 0具成尸 (男 2 8,女 32 ) 12 0侧颈椎 ,对脊神经沟外口宽度、深度及其沟内段脊神经前支横径进行观察 ,并统计脊神经前支横径与脊神经沟外口宽度之比。结果　①脊神经沟外口宽度、深度自颈 3至颈 6均逐渐增大 ,其平均值分别为 4 5± 1 2mm和4 3± 1 2mm ;② 3到 7颈神经前支横径逐渐增大 ,平均值为 2 9± 1 0mm ;③颈神经前支横径与脊神经沟外口宽度之比 ,颈 5最小 (1∶1 5 4 ) ,颈 4次之 (1∶1 6 7) ,颈 3最大 (1∶1 75 )。结论　脊神经沟与沟内段脊神经受累关系密切 ,下颈段 (5、6 )颈神经受累机率可能大于上颈段 (3、4 )。     

BMP4 is required in the anterior heart field and its derivatives for endocardial cushion remodeling, outflow tract septation, and semilunar valve development

The endocardial cushions play a critical role in septation of the four-chambered mammalian heart and in the formation of the valve leaflets that control blood flow through the heart. Within the outflow tract (OFT), both cardiac neural crest and endocardial-derived mesenchymal cells contribute to the endocardial cushions. Bone morphogenetic protein 4 (BMP4) is required for endocardial cushion development and for normal septation of the OFT. In the present study, we show that anterior heart field (AHF)-derived myocardium is an essential source of BMP4 required for normal endocardial cushion expansion and remodeling. Loss of BMP4 from the AHF in mice results in an insufficient number of cells in the developing OFT endocardial cushions, defective cushion remodeling, ventricular septal defects, persistent truncus arteriosus, and abnormal semilunar valve formation.     

A lectin horseradish peroxidase study of the origin of ascending fibers in the medial forebrain bundle of the rat. The lower brainstem

The origins of projections within the medial forebrain bundle from the lower brainstem were examined with the horseradish peroxidase technique. Labeled cells were found in at least 15 lower brainstem nuclei following injections of a conjugate or horseradish peroxidase and wheat germ agglutinin at various levels of the medial forebrain bundle. Dense labeling was observed in the following cell groups (from caudal to rostral): A1 (above the lateral reticular nucleus); A2 (mainly within the nucleus of the solitary tract); a distinct group of cell trailing ventrolaterally from the medial longitudinal fasciculus at the level of the rostral pole of the inferior olive; raphe magnus; nucleus incertus; dorsolateral tegmental nucleus (of Castaldi); locus coeruleus; nucleus subcoeruleus; caudal part of the dorsal (lateral) parabrachial nucleus; and raphe pontis. Distinct but light labeling was seen in raphe pallidus and obscurus, nucleus prepositus hypoglossi, nucleus gigantocellularis pars ventralis, and the ventral (medial) parabrachial nucleus. Sparse labeling was observed throughout the medullary and caudal pontine reticular formation. Several lower brainstem nuclei were found to send strong projections along the medial forebrain bundle to very anterior levels of the forebrain. They were: A1, A2, raphe magnus (rostral part), nucleus incertus, dorsolateral tegmental nucleus, raphe pontis and locus coeruleus. With the exception of the locus coeruleus, attention has only recently been directed to the ascending projections of most of the nuclei mentioned above. Evidence was reviewed indicating that fibers from lower brainstem nuclei with ascending medial forebrain bundle projections distribute to widespread regions of the forebrain.It is concluded from the present findings that several medullary cell groups are capable of exerting a direct effect on the forebrain and that the medial forebrain bundle is the major ascending link between the lower brainstem and the forebrain.     

Anterior displacement of the mandible for better exposure of the distal segment of the extracranial carotid artery

Summary Anterior displacement of the mandible (ADM) was performed in 34 patients undergoing surgery for malformations or atheromatous lesions of the distal segment of the extracranial internal carotid artery (ICA). This procedure greatly facilitates surgical access to the upper cervical region and has several advantages over mandibulotomy-mandibulectomy, namely: A shorter operating time, sparing of the inferior alveolar nerve and of the mandibular branch of cranial nerve VII, with no need for post-operative immobilization of the mandible. ADM permits the correction of ICA lesions extending as far as the first cervical vertebra. For lesions extending into the carotid canal ADM needs to be supplemented by various other procedures via the base of the skull.     

Enhancement of estradiol-induced DNA synthesis in the anterior pituitary gland by the peripheral-type benzodiazepine receptor ligand RO 5-4864

Summary The effects of peripheral (Ro 5-4864) and central-type (Ro 15-1788) benzodiazepine receptor ligands on estrogen-induced DNA synthesis in the rat anterior pituitary gland was investigated. As expected, a single injection of estradiol (250g per rat) significantly increased the uptake of³H-thymidine by anterior pituitary cells. Additional treatment with Ro 5-4864 potentiated the effects of estradiol on pituitary DNA synthesis. Under the same experimental conditions, no effect of Ro 15-1788 and sodium valproate, a GABA-transaminase inhibitor, was detected. These findings indicate the involvement of peripheral-type benzodiazepine receptors in the control of anterior pituitary cell proliferation.     

脊髓型颈椎病前路减压椎间隔合器临床应用

目的：探讨脊髓型颈椎病（CSM）前路减压、颈椎空心螺纹内固定器（CHTF）椎间融合,代替传统的前路减压,植骨融合的方法。方法：对18例CMS采用环锯减压再潜行扩大减压,植入CHTF无磁性医用钛合金突心螺纹内固定器椎间融合,随访疗效,进行分析,结果：植入CHTF术后随访6个月至1年,症状改善明显,稳定性好,生理曲度恢复达正常,无椎间隙高度丢失,无CHTF滑脱、移位。术后平均4．5个月椎间隙融合。     

Are We Being Fooled by Fluoroscopy? Distortion May Affect Limb-Length Measurements in Direct Anterior Total Hip Arthroplasty

BackgroundDistortion is an intrinsic phenomenon associated with image-intensified fluoroscopy that is both poorly understood and infrequently appreciated by orthopedic surgeons. Little information exists regarding its potential influence on intraoperative parameters during orthopedic surgery, let alone during direct anterior (DA) total hip arthroplasty (THA). The purpose of this study was to quantify the amount of potential error caused by fluoroscopic distortion during DA THA.MethodsIntra-operative fluoroscopic pelvic images from 74 DA THAs were reviewed by two independent readers. All images were obtained using the same fluoroscopic C-arm unit with a radiopaque grid attached to the image intensifier. The vertical distortion from a straight central horizontal line at the peripheries of images were measured and summed to yield the combined vertical distortion similar to how a surgeon calculates a side to side comparison of limb lengths. Simple linear regression was used to evaluate associations between total distortion and patient demographics, operating theaters, and various operative parameters.ResultsThe average combined distortion was 10.0mm (range 2.0-20.0mm). There was a significant difference in the average distortion observed in different theaters (P < .001). There was no association between distortion and patient demographics or fluoroscopic time (all, P > .05).ConclusionFluoroscopic distortion is unpredictable and can cause a substantial amount of error when comparing limb lengths during DA THA. This is a critical finding as this amount of inaccuracy could lead to unintended implant positioning and limb-length discrepancies if unaccounted for.     

Capsular Management in Direct Anterior Total Hip Arthroplasty: A Randomized,Single-Blind,Controlled Trial

BackgroundThe direct anterior approach (DAA) is a popular approach to total hip arthroplasty (THA). Unlike the posterior approach, the importance of anterior capsular management is unknown. This randomized controlled trial compares capsular repair versus capsulectomy.MethodsThis single-surgeon, single-blinded, parallel-group randomized controlled trial occurred between 2013 and 2016. Patients undergoing unilateral, primary THA for osteoarthritis consented to undergo blinded, simple randomization to anterior capsulotomy with repair or anterior capsulectomy. Primary outcome measures included hip range of motion, hip flexion strength, and pain with seated hip flexion. Secondary outcome measures included surgical time, estimated blood loss, postoperative complications, and hip disability and osteoarthritis outcome score. Data were prospectively collected intraoperatively, six weeks, six months, an average of over 5 years postoperatively.ResultsNinety-eight patients were ultimately enrolled in the trial; 50 received capsulectomy and 48 received capsulotomy. No significant differences were seen in preoperative demographics or in primary or secondary outcomes during this study. No difference was seen in pain at final follow-up at average > 5 years postoperatively.ConclusionThis study demonstrates that capsular management in DAA THA does not affect postoperative pain or range of motion. The anterior capsule’s role in prosthetic stability after DAA THA remains uncertain, but it does not currently appear that repair provides benefit and may lead to increased surgical time and blood loss. As such, capsular management in DAA THA is at surgeon discretion.     

Magnetic Resonance Imaging Assessment of Abductor Muscles Shortly After Curved Periacetabular Osteotomy

BackgroundCurved periacetabular osteotomy (CPO) is performed via an anterior approach without detachment of the hip abductor muscles. This study aimed to evaluate the abductor muscle status shortly after CPO on magnetic resonance imaging (MRI).MethodsWe prospectively evaluated 38 hips in 38 patients 1 week and 3 months after CPO between October 2017 and July 2019. The status of the abductor muscles was assessed on MRI using the following criteria: grade 0, normal; grade I, strain/edema; grade II, partial tear; and grade III, complete tear. We also evaluated associations between muscle status and patients’ characteristics.ResultsOne week after CPO, the gluteus maximus was classified as grade 0 in all patients. The gluteus medius was grade 0 in 84.2% of patients and grade I in 15.8%. The gluteus minimus was grade I in 55.3% of patients and grade II in 44.7%. Three months after CPO, both the gluteus maximus and gluteus medius were grade 0 in all patients, while the gluteus minimus was still grade I in 47.4%. There were no significant differences between patients with a grade 0 and grade I gluteus minimus at 3 months after CPO in patients’ characteristics (age and body mass index) or clinical scores (Harris Hip Score and Japanese Orthopedics Association score).ConclusionBoth the gluteus minimus and medius showed abnormal appearances on MRI 1 week after CPO, whereas only the gluteus minimus showed abnormalities 3 months after CPO. This abductor muscle status did not affect the postoperative Harris Hip Score or Japanese Orthopedics Association score.     

Impact of Dexamethasone on Length of Stay and Early Pain Control in Direct Anterior Approach Total Hip Arthroplasty With Neuraxial Anesthesia

BackgroundDexamethasone has been shown to reduce postoperative pain and opioid consumption for total joint arthroplasty patients; however, its impact on patients who received neuraxial anesthesia (NA) is not well described. We examined the impact of perioperative dexamethasone on outcomes for patients undergoing direct anterior approach total hip arthroplasty (THA) under NA.MethodsA retrospective review was conducted for 376 THA patients from a single institution. Univariate analysis was used to compare postoperative outcomes for 164 THA patients receiving dexamethasone compared to 212 who did not receive dexamethasone.ResultsNo differences in age, gender, body mass index, or American Society of Anesthesiologists (ASA) Score were observed between the groups. Patients receiving perioperative dexamethasone reported statistically significantly lower postanesthesia care unit (PACU) pain numeric rating scale (Dexamethasone 1.6 vs No dexamethasone 2.3, P = .014) and received lower PACU morphine milligram equivalents (MME) (Dexamethasone 8.57 vs No dexamethasone 11.44, P < .001). Patients receiving dexamethasone had significantly shorter LOS (Dexamethasone 29.40 vs No dexamethasone 35.26 hrs., P < .001).ConclusionPerioperative dexamethasone is associated with decreased postoperative pain and narcotic consumption, and shorter length of stay for patients undergoing primary direct anterior approach THA with NA.