Hip joint moments in symptomatic vs. asymptomatic people with mild radiographic hip osteoarthritis

Our primary objective was to examine external hip joint moments during walking in people with mild radiographic hip osteoarthritis (OA) with and without symptoms and disease-free controls. Three groups were compared (symptomatic with mild radiographic hip OA, n = 12; asymptomatic with mild radiographic hip OA, n = 13; OA-free controls, n = 20). Measures of the external moment (peak and impulse) in the sagittal, frontal and transverse plane during walking were determined. Variables were compared according to group allocation using mixed linear regression models that included individual gait trials, with group allocation as fixed effect and walking speed as a random effect. Participants with evidence of radiographic disease irrespective of symptoms walked 14–16% slower compared to disease-free controls (p = 0.002). Radiographic disease without symptoms was not associated with any altered measures of hip joint moment compared to asymptomatic OA-free controls once speed was taken into account (p ≥ 0.099). People with both mild radiographic disease and symptoms had lower external peak hip adduction moment (p = 0.005) and lower external peak internal rotation moment (p < 0.001) accounting for walking speed. Among angular impulses, only the presence of symptoms was associated with a reduced hip internal rotation impulse (p = 0.002) in the symptomatic group. Collectively, our observations suggest that symptoms have additional mechanical associations from radiographic disease alone, and provide insight into potential early markers of hip OA. Future research is required to understand the implications of modifying walking speed and/or the external hip adduction and internal rotation moment in people with mild hip OA.     

The influence of limb alignment and transfemoral amputation technique on muscle capacity during gait

Many factors influence successful outcomes following transfemoral amputation. One factor is surgical technique. In this study, the influence of limb alignment and surgical technique on a muscle’s capacity to generate force was examined using musculoskeletal modeling. Non-amputee and transfemoral amputee models were analyzed while hip adduction, femur length, and reattached muscle wrap position, tension and stabilization technique were systematically varied. With muscle tension preserved, wrap position and femur length had little influence on muscle capacity. However, limb alignment, muscle tension and stabilization technique notably influenced muscle capacity. Overall, myodesis stabilization provided greater muscle balance and function than myoplasty stabilization.     

Autofluorescence imaging for recurrence detection in skin cancer postoperative scars

This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development.     

Sex determination of fetal and neonate skeletons by means of discriminant analysis

Facing the requirements of refined paleodemographical analyses, the access to the early ontogenetic sex ratio of skeletal populations is an important feature. Using raw data provided byFazekas & Kosa (1978) for a sample of known sex, discriminant functions are derived from hip and thigh bone dimensions that allow an almost unbiased classification of more than 70% of fetal and neonate individuals.     

Oxygen-derived free radicals and hemolysis during open heart surgery

Reperfusion injury occurs during open-heart surgery after prolonged cardioplegic arrest. Cardiopulmonary bypass also is known to cause hemolysis. Since reperfusion of ischemic myocardium is associated with the generation of oxygen free radicals, and since free radicals can attack a protein molecule, it seems reasonable to assume that hemolysis might be the consequence of free radical attack on hemoglobin protein. The results of this study demonstrated that reperfusion following ischemic arrest caused an increase in free hemoglobin and free heme concentrations, simultaneously releasing free iron and generating hydroxyl radicals. In vitro studies using pure hemoglobin indicated that superoxide anion generated by the action of xanthine oxidase on xanthine could release iron from the heme ring and cause deoxygenation of oxyhemoglobin into ferrihemoglobin. This study further demonstrated that before the release of iron from the heme nucleus, oxyhemoglobin underwent deoxygenation to ferrihemoglobin. The released iron can catalyze the Fenton reaction, leading to the formation of cytotoxic hydroxyl radical (OH·). In fact, the formation of OH. in conjunction with hemolysis occurs during cardiac surgery, and when viewed in the light of the in vitro results, it seems likely that oxygen-derived free radicals may cause hemolysis during cardiopulmonary bypass and simultaneously release iron from the heme ring, which can catalyze the formation of OH·.     

Power and work produced in different leg muscle groups when rising from a chair

The aim of this study was to determine the power output and work done by different muscle groups at the hip and knee joints during a rising movement, to be able to tell the degree of activation of the muscle groups and the relationship between concentric and eccentric work. Nine healthy male subjects rose from a chair with the seat at knee level. The moments of force about the hip and knee joints were calculated semidynamically. The power output (P) and work in the different muscle groups surrounding the joints was calculated as moment of force times joint angular velocity. Work was calculated as: work = f Pdt. The mean peak concentric power output was for the hip extensors 49.9 W, hip flexors 7.9 W and knee extensor 89.5 W. This power output corresponded to a net concentric work of 20.7 J, 1.0 J and 55.6 J, respectively. There was no concentric power output from the knee flexor muscles. Energy absorption through eccentric muscle action was produced by the hip extensors and hip flexors with a mean peak power output of 4.8 W and 7.4 W, respectively. It was concluded that during rising, the hip and knee muscles mainly worked concentrically and that the greatest power output and work were produced during concentric contraction of the knee and hip extensor muscles. There was however also a demand for eccentric work by the hip extensors as well as both concentric and eccentric work by the hip flexors. The knee flexor muscles were unloaded.     

经皮椎间孔镜手术不同入路治疗单节段腰椎间盘突出症疗效对比的回顾性研究

摘要 目的：对比经皮椎间孔镜手术不同入路治疗单节段腰椎间盘突出症（LDH）的疗效。方法：回顾性分析2018年5月至2020年5月我院收治的80例单节段LDH患者的临床资料。患者均接受经皮椎间孔镜手术,根据手术入路的不同,分为经椎间孔入路（PETD）组和经椎板间入路（PEID）组,每组均40例。比较两组的手术相关指标、术后恢复指标、手术前后的Oswestry功能障碍指数（ODI）和视觉模拟评分法（VAS）评分,以及术后并发症情况。结果：PEID组的手术时间短于PETD组,X线透视次数少于PETD组,差异均有统计学意义（P<0.05）。两组的术中出血量相比,差异无统计学意义（P>0.05）。PETD组的术后卧床时间短于PEID组,差异有统计学意义（P<0.05）。两组的术后1 d直腿抬高试验角度、住院时间、复发率相比,差异无统计学意义（P>0.05）。两组患者术后1 d、术后3个月、术后12个月的ODI评分、VAS评分均低于术前,且呈降低趋势（P<0.05）;同一时间点两组间ODI评分、VAS评分比较,差异无统计学意义（P>0.05）。两组的并发症发生率相比,差异无统计学意义（P>0.05）。结论：PETD和PEID经皮椎间孔镜手术治疗单节段LDH总体疗效和安全性接近,PETD可缩短术后卧床时间,PEID的操作难度更低、可减少手术时间和X线透视次数。临床中应视患者实际情况选择合适的入路。     

丙泊酚联合七氟醚麻醉在先天性心脏病介入手术患儿中的心肌保护作用及对苏醒质量和应激反应的影响

摘要 目的：研究丙泊酚联合七氟醚麻醉在先天性心脏病介入手术患儿中的心肌保护作用及对苏醒质量和应激反应的影响。方法：选择2020年1月~2022年4月期间在苏州大学附属儿童医院接受先天性心脏病介入手术患儿96例,按照双色球法将患儿分为对照组（n=48,接受瑞芬太尼、丙泊酚麻醉）和观察组（n=48,接受丙泊酚、七氟醚麻醉）。对比两组患儿心率、呼吸频率、平均动脉压、苏醒质量、心肌损伤指标、应激反应指标和不良反应发生率。结果：两组置喉罩时（T1）~拔除喉罩（T4）时间点心率、呼吸频率、平均动脉压下降后升高,观察组高于对照组同时间点（P<0.05）。观察组的苏醒时间、拔管时间均短于对照组（P<0.05）。两组术毕、术后24 h肌酸磷酸激酶同工酶（CK-MB）、心肌肌钙蛋白（cTnI）升高后下降,观察组低于对照组同时间点（P<0.05）。两组术毕、术后24 h血糖、皮质醇升高后下降,观察组低于对照组同时间点（P<0.05）。两组不良反应发生率组间对比,差异不显著（P>0.05）。结论：丙泊酚联合七氟醚麻醉应用于先天性心脏病介入手术中,可减轻患儿的应激反应,稳定机体血流动力学波动,同时还可发挥心肌保护作用,提高苏醒质量。     

The response of plasma gastric-inhibitory polypeptide (GIP) to slow and fast glucose ingestion in Billroth II resected patients and normal controls

Eight Billroth II resected patients and 8 normal controls were given two oral glucose loads, one ingested within 2 min, and the other ingested slowly over 80 min. In the Billroth II resected group, the integrated plasma GIP release was significantly higher after the fast than after the slow glucose ingestion. In this group the integrated plasma GIP release was also significantly higher than in the control group, but only after the fast glucose ingestion. These findings indicate that the rate of glucose delivery into the intestine may be of importance in the plasma GIP response to oral glucose.     

Higher medially-directed joint reaction forces are a characteristic of dysplastic hips: A comparative study using subject-specific musculoskeletal models

Acetabular dysplasia is a known cause of hip osteoarthritis. In addition to abnormal anatomy, changes in kinematics, joint reaction forces (JRFs), and muscle forces could cause tissue damage to the cartilage and labrum, and may contribute to pain and fatigue. The objective of this study was to compare lower extremity joint angles, moments, hip JRFs and muscle forces during gait between patients with symptomatic acetabular dysplasia and healthy controls. Marker trajectories and ground reaction forces were measured in 10 dysplasia patients and 10 typically developing control subjects. A musculoskeletal model was scaled in OpenSim to each subject and subject-specific hip joint centers were determined using reconstructions from CT images. Joint kinematics and moments were calculated using inverse kinematics and inverse dynamics, respectively. Muscle forces and hip JRFs were estimated with static optimization. Inter-group differences were tested for statistical significance (p ≤ 0.05) and large effect sizes (d ≥ 0.8). Results demonstrated that dysplasia patients had higher medially directed JRFs. Joint angles and moments were mostly similar between the groups, but large inter-group effect sizes suggested some restriction in range of motion by patients at the hip and ankle. Higher medially-directed JRFs and inter-group differences in hip muscle forces likely stem from lateralization of the hip joint center in dysplastic patients. Joint force differences, combined with reductions in range of motion at the hip and ankle may also indicate compensatory strategies by patients with dysplasia to maintain joint stability.