掌指关节的三维解剖及形态分析

目的：观测掌指关节关节面的几何形态,为人工关节的设计和应用提供解剖学依据。方法：10只成人手标本,解剖掌指关节,测量侧副韧带起点距掌骨头关节面的直线距离,三维数据检测仪获得关节面三维坐标数据,应用SPSS软件进行统计分析和成像。结果：掌骨头有双髁结构,桡侧髁略大,第1掌骨头形态特殊;各掌骨头高度的比较无显著差异;其掌侧关节面大于背侧,第2、3掌骨头关节面面积明显较大。近节指骨底在形态、高度和面积方面各序列相似;各序列侧副韧带起点桡侧较尺侧距离掌骨头关节面远。结论：手指人工关节的设计应符合解剖形态,并根据各序列形态的差异进行个体化设计,尤其拇指更应区别对待;手指人工关节的设计和应用中应注意软组织保护,关节的切除范围应注意保留侧副韧带的起止点。     

Techniques of exposure for the stiff total knee

Primary and revision total knee arthroplasty have become common orthopaedic procedures. The operating surgeon, at times, may be faced with a difficult surgical case due to soft tissue contractures or bone deformities. A review of multiple surgical techniques using soft tissue releases and osteotomies are presented including their potential complications. Although these techniques are aimed at the atypical operative case, the operating surgeon may utilize them for ‘routine’ exposures as well. Importance is focused on the functional integrity of the knee extensor mechanism.     

Intrarater Reliability of Functional Performance Tests for Subjects With Patellofemoral Pain Syndrome

OBJECTIVE: Patellofemoral pain syndrome (PFPS) is a common clinical entity seen by the sports medicine specialist. The ultimate goal of rehabilitation is to return the patient to the highest functional level in the most efficient manner. Therefore, it is necessary to assess the progress of patients with PFPS using reliable functional performance tests. Our purpose was to evaluate the intrarater reliability of 5 functional performance tests in patients with PFPS. DESIGN AND SETTING: We used a test-retest reliability design in a clinic setting. SUBJECTS: Two groups of subjects were studied: those with PFPS (n = 29) and those with no known knee condition (n = 11). The PFPS group included 19 women and 10 men with a mean age of 27.6 +/- 5.3 years, height of 169.80 +/- 10.5 cm, and weight of 69.59 +/- 15.8 kg. The normal group included 7 women and 4 men with a mean age of 30.3 +/- 5.2 years, height of 169.55 +/- 9.9 cm, and weight 69.42 +/- 14.6 kg. MEASUREMENTS: The reliability of 5 functional performance tests (anteromedial lunge, step-down, single-leg press, bilateral squat, balance and reach) was assessed in 15 subjects with PFPS. Secondly, the relationship of the 5 functional tests to pain was assessed in 29 PFPS subjects using Pearson product moment correlations. The limb symmetry index (LSI) was calculated in the 29 PFPS subjects and compared with the group of 11 normal subjects. RESULTS: The 5 functional tests proved to have fair to high intrarater reliability. Intrarater reliability coefficients (ICC 3,1) ranged from.79 to.94. For the PFPS subjects, a statistical difference existed between limbs for the anteromedial lunge, step-down, single-leg press, and balance and reach. All functional tests correlated significantly with pain except for the bilateral squat; values ranged from.39 to.73. The average LSI for the PFPS group was 85%, while the average LSI for the normal subjects was 97%. CONCLUSIONS: The 5 functional tests proved to have good intrarater reliability and were related to changes in pain. Future research is needed to examine interrater reliability, validity, and sensitivity of these clinical tests.     

Source of the slippage in the universal joints of the Hoffmann external fixator

An investigation was conducted to determine what improvements in the resistance to slippage could be obtained in selected interfaces (rod/clip torsional, cheek/bowl and cheek/clip) of the Hoffmann external fixator. The modification involved changing the standard wing-nut clamp for a bolt with a thread of 7 mm and a 1 mm pitch and placing an FAG 28–303 thrust-bearing (needle roller and cage assembly) between the bolt and the cheek. The results showed a significant improvement in the slippage values of all interfaces; increases of approximately six times were obtained at all torque values of the wing-nut clamp or fastener tested. Such improvements would markedly increase the reliability of external fixation systems and thus reduce the incidence of loss-of-reduction of fracture due to slippage of the universal joint.     

Study of the carrying angle of the human elbow joint in full extension: a morphometric analysis

This study measured the carrying angle of the elbow joint in full extension in 600 students, using the supplementary angle to that between the longitudinal axis of the arm and that of the forearm. The mean carrying angle was 12.88°±5.92: 10.97°±4.27 in men and 15.07°±4.95 in women. The carrying angle changes with skeletal growth and maturity. The angle is always greater on the side of the dominant hand. We confirmed the inverse relationship between the carrying angle and the intertrochanteric diameter. Also, the type of constitution influences the value of the carrying angle, especially in women.     

Die Beanspruchung des menschlichen Ellenbogengelenks

Zusammenfassung Bei 80 Objekten werden die Gelenkflächen des menschlichen Ellenbogengelenks untersucht. Die Trochlea und das Capitulum humeri sowie das Caput radii zeigen keine nennenswerten Unterschiede in der Ausdehnung der mit typischem Gelenkknorpel bedeckten Flächen. Dagegen lassen sich für die Ulnazange drei charakteristische Formgruppen abgrenzen: In 3 Fällen kann eine einheitliche Knorpelfläche beobachtet werden. Bei etwa zwei Drittel der untersuchten Objekte liegt im mittleren Bereich der Incisura trochlearis in horizontaler Richtung ein 2–5 mm breiter knorpelfreier Streifen, der den Gelenkknorpel in 2 vollständig getrennte Flächen unterteilt. Das restliche Drittel der Objekte besitzt eine unvollständige Trennung der Gelenkfläche. Unter Berücksichtigung der Vorstellungen von Pauwels über die causale Histogenese der mesenchymalen Stützgewebe sowie der Materialverteilung im Knochengewebe in Abhängigkeit von der einwirkenden Spannungsgröße werden die morphologischen Befunde den für die jeweiligen Skeletelemente von Pauwels ermittelten Spannungsdiagrammen gegenübergestellt. An der Trochlea und dem Capitulum humeri und am Caput radii findet sich eine geradezu ideale Übereinstimmung in der Ausdehnung der Knorpelfläche und der Knochendichte unter den Gelenkflächen mit den entsprechenden Spannungsdiagrammen. An der Ulna trifft dies nur für einen geringen Teil der Objekte zu. Für die unterschiedliche Ausgestaltung der Incisura trochlearis werden zwei mögliche Ursachen diskutiert: 1. die Resultierende R verharre während des Bewegungsablaufes in einzelnen Positionen innerhalb der Incisura trochlearis verschieden lange; 2. der Krümmungsradius der Trochlea humeri sei größer als derjenige im mittleren Bereich der Ulnazange, so daß hier wegen des fehlenden Kontaktes der Gelenkflächen keine Druckübertragung möglich ist.

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The stress of the human elbow jointI. Functional morphology of the articular surfaces

Summary The articular surfaces of 80 human elbow joints are analysed. The trochlea and capitulum humeri and the caput radii of the investigated individuals show no particular differences in the extent of their surfaces covered with typical articular cartilage. On the other hand the form of the incisura trochlearis is rather variable. Three characteristic formgroups are to be discerned. In three objects a continuous cartilage surface has been observed. In 50 of the investigated joints there is a small intersection free from cartilage in the midst of the incisura trochlearis, dividing the articular cartilage in two isolated surfaces. In the rest of the analysed objects the articular surface is divided only partially. According to Pauwels' hypothesis on the causal histogenesis of the mesenchymal supporting tissues and of the density distribution of the bone dependence upon the magnitude of the local unit stress the morphological findings in the single investigated parts of the elbow joint are confronted with the corresponding stress diagram as described by Pauwels. In the trochlea and capitulum humeri and in the caput radii a nearly ideal correspondence of the extent of the articular surface and the density of the bone tissue with the unit stress diagrams are found. In the ulna this correspondence exists only in few of the analysed objects. For the different form of the incisura trochlearis two possible explanations are discussed: 1, during the motion the resultant of forces may stay for a different time in their single positions in the incisura trochlearis; 2. the curvature radius of the trochlea humeri may be greater than that one of the incisura trochlearis in the central area. So no pressure occurs in this part of the articular surface.

Mit freundlicher Unterstützung durch die Deutsche Forschungsgemeinschaft.     

计算机辅助全膝置换中股骨力线定位精度的实验研究

摘要利用光学定位追踪仪确定全膝置换中患者的股骨头中心从而确定其股骨力线，在力线的定位精度分析中，首次采用股骨的三维重建模型进行精度校验。实验结果表明通过追踪固定于股骨末端的刚性定位器即能确定精确的股骨力线，与传统的髓内定位相比，不仅可重复性好，而且大大地提高了术中股骨力线的位置精度，将其位置偏差减小到10以内。     

Morphomechanics of the humero-ulnar joint: II. Concave incongruity determines the distribution of load and subchondral mineralization

Background: A deeper joint socket (concave incongruity) is found at most angles of flexion of the humero-ulnar joint and maintained over a wide range of physiological loading. It is, however, unclear how far this incongruity affects the distribution of load and subchondral mineralization of this joint as compared with a congruous configuration. Methods: Two nonlinear, axisymmetrical finite element models with two cartilage layers were constructed, one congruous and one incongruous, with a joint space of realistic magnitude. The distribution of subchondral mineralization was determined by computed tomography osteoabsorptiometry in the same six specimens that were investigated in the first part of the study, and compared with the biomechanical data obtained there and the predictions of the models. Results: In the congruous case, the center of the socket is highly loaded, whereas the periphery does not experience mechanical stimulation. A central bone density maximum is predicted. With concave incongruity the position of the contact areas shifts from the joint margin towards the center as the load increases, and the peak stresses are considerably lower. A bicentric ventro-dorsal distribution pattern of subchondral mineralization is predicted, and this is actually found in the six specimens. Conclusions: Concave incongruity is shown to determine load transmission and subchondral mineralization of the humero-ulnar joint. It is suggested that this shape leads to a more even distribution of stress, provides intermittent stimulation of the cartilaginous tissue, and has beneficial effects on the metabolism, nutrition, and lubrication of the articular cartilage during cyclic loading. © 1995 Wiley-Liss, Inc.     

Examination of the Diagnostic Value and Estimation of the Chaos Phenomenon in Temporomandibular Joint Sounds Using Fractal Dimension

.The aim of this study is to estimate the chaos phenomenon in temporomandibular joints (TMJ) sound using fractal dimension (FD), and to examine the diagnostic value of the FD in comparing TMJ sounds produced by 6 asymptomatic and 25 symptomatic TMJ. Multiple mandibular opening and closing cycles recorded were used to calculate the waveform dimension and correlation dimension in the FD. Chaos in the TMJ sounds was estimated by the FD that was saturated with some constant value to an increase of embedding dimension. Results reveal that fractal analysis produces a high degree of reproducibility within, and similarity across subjects, and indicate that both FD values of the asymptomatic TMJ sounds are significantly higher than those of the symptomatic. These findings suggest that chaos is present in TMJ sounds and the difference in the FD is of diagnostic value in evaluation of pathological change in TMJ sound signals.     

模拟股骨置入人工关节扭转与应力松弛蠕变的实验研究

研究了在相同扭矩作用下,正常组股骨和以生物学和骨水泥固定置入人工关节组股骨标本扭转角度,还对正常股骨、生物学固定股骨和骨水泥固定股骨进行应力松弛、蠕变实验,为临床提供生物力学参数。以电子万能试验机对正常对照组、股骨置入人工关节骨水泥固定组、股骨置入人工关节生物学固定组标本进行扭转和粘弹性实验研究。得出了各组标本在相同扭矩下的扭转角度及悬臂弯曲状态下,正常组和置入人工关节组标本应力松弛、蠕变数据和曲线。对实验数据进行归一化处理,得出了正常组和置入人工关节组标本的归一化应力松弛函数,归一化蠕变函数及曲线。表明:骨水泥固定组扭转角比生物学固定组小,说明骨水泥固定有较好的稳定性,其应力松弛、蠕变量丢失小。骨水泥固定组较生物学固定组3600s应力松弛、蠕变量大。