后交叉韧带断裂对外侧半月板生物力学的影响

目的:探讨后交叉韧带(Posterior cruciate ligament,PCL)损伤后对外侧半月板各部位生物力学特性的影响,为PCL断裂后外侧半月板损伤的防治避免骨性关节炎提供力学理论依据.方法:自愿捐献新鲜成年男性正常膝关节标本共10具,年龄21～36岁,平均32.3岁,为非对称性,左、右膝关节各5具.置于自制运动夹具上并通过电子试验机连续轴向加载0～800N负荷模拟膝关节的受力,采用压力感受器分别测定PCL完整组及PCL断裂组外侧半月板前角体部和后角于屈膝0、30、60及90°时应变值.结果:膝关节0°位,在PCL完整时,前角、体部和后角的应变均为负值,为压应变,当PCL完全切断时,前角、体部应变在各种载荷下较完整时均出现负向减小,而后角的应变却出现负向增大.膝关节30°、60°、90°位,PCL完整时前角、体部的应变为正值,是拉应变,且随载荷和角度的增大而增大,后角的应变是负值,为压应变,且随载荷和角度的增大而负向增大,PCL断裂组应变值明显大于完整组.不同角度不同载荷下两组差异均有统计学意义(P＜0.05).结论:PCL断裂会对外侧半月板产生显著的生物力学影响,这也为伤后避免膝关节屈曲负重和早期重建PCL保护半月板功能避免骨性关节炎提供了力学理论依据.     

前交叉韧带不同断裂程度对髌骨内外侧关节面的生物力学影响

目的:探讨前交叉韧带(ACL)完全断裂和部分断裂对髌骨内外侧关节面生物力学的影响.方法:10例新鲜正常成人膝关节标本作为ACL完整组,在200N轴向载荷下,测试膝关节0°、30°、60°、90°髌骨内外侧关节面应变,测试完毕后随机将标本造模成前内侧束(AMB)切断组和后外侧束(PLB)切断组,各5例,在上述条件下测试,再将ACL中下1/3全切作为全切组进行测试.结果:膝伸直0°位各组应变无显著性差异(P＞0.05),膝屈曲30°、60°、90°各组间均有显著性差异(P＜0.05),其应变变化趋势为ACL完整组＞PLB切断组＞AMB切断组＞全切组.且髌骨内侧面应变小于髌骨外侧面应变(P＜0.05).结论:ACL完全断裂,在不同栽荷和角度下,对髌骨内外侧关节面的应变均有影响.ACL部分断裂在膝关节屈曲30°、60°、90°位可引起髌骨内外侧生物力学改变.ACL完全断裂,髌骨外侧应变高于髌骨内侧应变,其意义尚需进一步探讨.     

前交叉韧带重建后的功能康复

目的:探讨关节镜下前交叉韧带损伤重建术后的功能康复.方法:回顾分析了1990年～1997年间我科收治并且目前能随访到的21例膝前交叉韧带损伤后采用关节镜下双股半腱肌腱重建的患者,术后均采用我科制订的系统康复治疗计划进行康复训练,随访时间98～168个月,平均127,36个月.对其术前和近期的自我感觉、查体及Lysholm膝关节评分、IKDC(International KneeDocumentation Committee)分级标准评定的情况进行分析.结果:21例术前弹响、交锁和打软腿的症状均消失,浮髌试验均为阴性,均无过伸痛.关节轻度疼痛11例,Lachman征阳性3例,前抽屉试验阳性8例,但均无关节不稳的主诉.无取腱造成的其它并发症.Lysholm膝关节评分术后优于术前,差异有显著性意义(P＜0.05).IKDC评分结果术后明显优于术前.术后平均4.65个月恢复日常活动,恢复体育锻炼时间均在6个月左右.有2例伸直受限(差10°),所有患者屈曲活动度基本正常.结论:ACL损伤重建的术后患者经过我们所设计实施的康复计划的训练后,没有关节不稳的主诉,屈伸活动度满足日常生活需要,对术后的功能均较满意.     

本体感觉训练联合肌内效贴对前交叉韧带断裂术后患者肢体肿胀程度、运动平衡功能及生活质量的影响

摘要 目的：观察本体感觉训练联合肌内效贴对前交叉韧带断裂术后患者肢体肿胀程度、运动平衡功能及生活质量的影响。方法：选择2019年1月-2022年1月期间我院接收的120例行前交叉韧带断裂术患者,按照信封抽签法将患者分为对照组（60例,本体感觉训练）和研究组（60例,对照组的基础上接受肌内效贴干预）。对比两组优良率、肢体肿胀程度、运动平衡功能及生活质量。结果：研究组的优良率高于对照组（P<0.05）。两组治疗2周后、治疗4周后肢体肿胀值减小,且研究组低于对照组（P<0.05）。两组治疗4周后Fugl-Meyer运动量表（FMA）、Berg 评分量表（BBS）评分升高,且研究组高于对照组（P<0.05）。两组治疗4周后总体/精神健康、生理/社会功能、活力、躯体疼痛和情感/生理职能评分升高,且研究组高于对照组（P<0.05）。结论：本体感觉训练联合肌内效贴对前交叉韧带断裂术后患者,可有效减轻肢体肿胀程度,改善运动平衡功能及生活质量,效果显著。     

Comparison of Medial and Lateral Meniscus Root Tears

The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients’ ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29–71 years) and 30 years (range: 14–62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is common in patients with MMRTs. However, it is rare in patients with LMRTs, which are more commonly associated with a history of trauma and ACL tears.     

The Congruency Effect in the Posterior Medial Frontal Cortex Is More Consistent with Time on Task than with Response Conflict

The posterior medial frontal cortex (pMFC) is thought to play a pivotal role in enabling the control of attention during periods of distraction. In line with this view, pMFC activity is ubiquitously greater in incongruent trials of response-interference (e.g., Stroop) tasks than in congruent trials. Nonetheless, the process underlying this congruency effect remains highly controversial. We therefore sought to distinguish between two competing accounts of the congruency effect. The conflict monitoring account posits the effect indexes a process that detects conflict between competing response alternatives, which is indexed by trial-specific reaction time (RT). The time on task account posits the effect indexes a process whose recruitment increases with time on task independent of response conflict (e.g., sustained attention, arousal, effort, etc.). To distinguish between these accounts, we used functional MRI to record brain activity in twenty-four healthy adults while they performed two tasks: a response-interference task and a simple RT task with only one possible response. We reasoned that demands on a process that detects response conflict should increase with RT in the response-interference task but not in the simple RT task. In contrast, demands on a process whose recruitment increases with time on task independent of response conflict should increase with RT in both tasks. Trial-by-trial analyses revealed that pMFC activity increased with RT in both tasks. Moreover, pMFC activity increased with RT in the simple RT task enough to fully account for the congruency effect in the response-interference task. These findings appear more consistent with the time on task account of the congruency effect than with the conflict monitoring account.     

Functional Principles of Posterior Septal Inputs to the Medial Habenula

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Posterior Cerebral Artery Angle and the Rupture of Basilar Tip Aneurysms

Since the initial publication of the International Study of Unruptured Intracranial Aneurysms (ISUIA), management of unruptured intracranial aneurysms has been mainly based on the size of the aneurysm. The contribution of morphological characteristics to treatment decisions of unruptured aneurysms has not been well studied in a systematic and location specific manner. We present a large sample of basilar artery tip aneurysms (BTA) that were assessed using a diverse array of morphological variables to determine the parameters associated with ruptured aneurysms. Demographic and clinical risk factors of aneurysm rupture were obtained from chart review. CT angiograms (CTA) were evaluated with Slicer, an open source visualization and image analysis software, to generate 3-D models of the aneurysms and surrounding vascular architecture. Morphological parameters examined in each model included aneurysm volume, aspect ratio, size ratio, aneurysm angle, basilar vessel angle, basilar flow angle, and vessel to vessel angles. Univariate and multivariate analyses were performed to determine statistical significance. From 2008–2013, 54 patients with BTA aneurysms were evaluated in a single institution, and CTAs from 33 patients (15 ruptured, 18 unruptured) were available and analyzed. Aneurysms that underwent reoperation, that were associated with arteriovenous malformations, or that lacked preoperative CTA were excluded. Multivariate logistic regression revealed that a larger angle between the posterior cerebral arteries (P1-P1 angle, p = 0.037) was most strongly associated with aneurysm rupture after adjusting for other morphological variables. In this location specific study of BTA aneurysms, the larger the angle formed between posterior cerebral arteries was found to be a new morphological parameter significantly associated with ruptured BTA aneurysms. This is a physically intuitive parameter that can be measured easily and readily applied in the clinical setting.     

波形蛋白在不同年龄大鼠脊髓后角表达

目的:检测波形蛋白(Vimentin)在不同年龄大鼠脊髓后角的表达,探讨Vimentin在大鼠脊髓成熟和衰老过程中的表达变化.方法:对新生(7天龄)、成年(2月龄)、老年(24月龄)大鼠脊髓进行Vimentin和胶质纤维酸性蛋白(GFAP)免疫荧光双标染色,并进行荧光强度的定量分析.结果:新生组Vimentin阳性产物荧光强度(59.73±9.92)较强,成年组Vimentin阳性产物荧光强度(43.26±7.99)较新生组弱,老年组Vimentin阳性产物荧光强度(40.65±6.84)较成年组弱,两组间差异均有统计学意义(P＜0.01).结论:脊髓后角新生组、成年组、老年组Vimentin的表达随着年龄的增长而降低.