X-Ray Study of the Cat Hindlimb During Treadmill Locomotion

With pulsed X-ray cinematography we have analysed the angular excursions of the distal hindlimb joints (proximal interphalangeal, PIP; metatarsophalangeal, MTP; ankle) in cats walking on a treadmill. These distal joints transmit the body weight and the dynamic forces onto the ground. We have included the knee and hip joints in the analysis to relate the angular excursions of the proximal and distal joints and to verify the data previously obtained with external markers on the kinematics of the proximal joints. At the beginning of the stance phase the PIP joints flexed rapidly, the MTP joints extended slowly and the ankle and knee yielded under body weight. Whereas the PIP joints maintained a rather constant angular position of −75° throughout the stance phase, extension continued in the MTP joints from −230° at touch-down to −270° at the end of the stance phase. Around 50 ms before lift-off the MTP joints flexed rapidly. Early (−30 ms) after lift-off this flexion changed into a slow extension. The PIP joints extended swiftly at the stance-swing transition and moderately at the end of the swing phase. During the middle part of the swing phase they flexed slowly. Small rotatory movements around the long axis of the foot took place in the last 100 ms of the swing phase. The results of this study on the distal joints are discussed in relation to the placing of the paw, to the translation of forward propulsion into a MTP movement and to the lifting of the paw (conventionally described as toe curling). They show a differentiated mechanical interaction between the different distal limb joints during these different phases, which must be known in detail to interpret the corresponding electromyographic data and to understand how the hip is moved forward over the MTP joints which serve as the final pivot during stance.     

腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析

目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。     

Prosthetic joint infectionsin the elderly

Total joint arthroplasty is among the most remarkable advances in orthopaedic surgery for the elderly, enabling themto regain physical function and be free of pain. Although uncommon, infection of the prosthetic joint causes serious morbidity leading to poor functional outcome with a mortality approaching 8% in the elderly. Most infections occur through inoculation of the prosthesis at the time of implantation and are due to Gram-positive cocci, although a third of the episodes are due to Gram-negative bacilli from a secondary focus. The management presents a major clinical and therapeutic challenge due to systemic and local comorbid conditions in the elderly. Medical and surgical treatment decisions for infected joint prosthesis are complex and should be individualized in each case. Optimal nutrition is essential for a successful outcome. Adverse reactions to medications are more common in the elderly due to end organ dysfunction and drug-drug interactions.     

A comparative study of the anatomical,radiological and therapeutic features of the lumbar facet joints

Summary An anatomical study of the lumbar apophyseal joints was carried out to facilitate recognition of facet joint lesions, which we now examine routinely by percutaneous arthrography. Special attention was given to the configuration of the different compartments of the joint space and to its relationships with the contents of the intervertebral foramen. The abnormalities seen on lumbar facet joint arthrography are very varied; two major groups should be stressed: synovial fringe hypertrophy and pseudodiverticular synovial ectasia. The percutaneous approach to lumbar facet joint arthrography allows it to be used a therapeutic measure, with injection of anti-inflammatory drugs into the joint space, the beneficial effects of which were confirmed in our series. The precision, efficiency and cost-effectiveness of this outpatient technique justify and should encourage its more widespread application in the diagnosis and treatment of low back pain.     

颈椎肿瘤单侧关节突关节切除后的稳定性重建

目的：探讨颈椎肿瘤单侧关节突关节切除后稳定性重建的方法及效果。方法：对1999—2005年存我院骨科手术治疗且得到随访的18例切除单侧关节突关节的颈椎肿瘤患者的资料进行分析，男10例，女8例；年龄16～72岁，平均46岁。神经根受压表现为主者10例，VAS评分2～8分，平均4．2分；脊髓压迫表现为主者8例．ASIA分级C级5例．D级3例。均采用颈后路患侧关节突关节、侧块切除，完整切除肿瘤组织，其中10例行单侧侧块钢板固定植骨融合，8例行双侧侧块钢板固定植骨融合。结果：随访3—60个月，平均20个月，1例透明细胞癌肺转移患者死亡．余存活无复发。10例神经根受压表现为主者术后疼痛VAS评分0—4分，平均1．6分。8例脊髓压迫表现为主者，5例术前C级者术后C级2例、E级3例，3例术前D级者术后D级2例．E级l例。双侧侧块钢板固定植骨融合者术后3个月4例m现骨性融合（其中1例3个月后失访），6个月7例达到骨性融合，内固定无断裂、松动、移位。无颈椎不稳。单侧侧块钢板固定植骨融合者．1例术后5个月出现颈部疼痛；9例在术后9个月骨性融合；1例12个月时仍未能骨性融合，螺钉松动。结论：颈后路侧块钢板同定植骨融合可以实现颈椎肿瘤单侧关节突关节切除后的颈椎稳定性重建。     

Bilateral fracture dislocation of the sacroiliac joint

 We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional CT images were invaluable in the diagnosis and assessment of this injury.     

Cloning of a human immunoglobulin gene fragment containing both VH-D and D-JH rearrangements: Implication for VH-D as an intermediate to VH-D-JH formation

In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that V_H-D and D-J_H recombination took place in a single allele. Both V_H-D and D-J_H complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a V_H-D(-D)-J_H formation. With this finding, we propose a novel pathway, in which the V_H-D complex is an intermediate in the formation of a functional V_H exon.     

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.     

Radiologic anatomy of the metacarpophalangeal joints II to V

Summary The metacarpophalangeal (MCP) joints II to V of 21 hands were examined radiologically and arthrographically. Different recesses of the joint cavity were demonstrated both radiologically and macroscopically, with a dominating dorsal recess. The existing forms of the dorsal recess were one-tailed, two-tailed, three-tailed, symmetric and caplike. Additionally, a palmar recess was found in the specimens examined, which presented as a small protrusion of the capsule and lay between the metacarpal head and the palmar plate. Furthermore, a distal recess was filled and unfolded in almost all the cases. Lateral recesses were found in the radial and ulnar directions beneath the collateral ligaments. The dorsal recess, due to its ability to collect fluid, is of clinical importance in pathologic processes causing effusions, while the clinical importance of the lateral recesses lie in their proximity to the stabilizing collateral ligaments of the metacarpophalangeal joints. The above mentioned recesses were seen as normal formations of the MCP joints and should therefore be taken into account in pathologic processes in this area.

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Radioanatomie des articulations métacarpo-phalangiennes des 2ème au 5ème doigts

Résumé Les articulations métacarpophalangiennes (MCP) des 2ème au 5ème doigts de 21 mains ont été explorées en radiographie standard et en arthrographie. Plusieurs récessus articulaires, dont un récessus dorsal prédominant, ont été mis en évidence à la fois sur les radiographies et macroscopiquement. Les récessus dorsaux observés pouvaient comprendre une, deux ou trois cornes ou prendre un aspect de coiffe. Un récessus palmaire a été également trouvé sur 49 pièces sous la forme d'une petite expansion capsulaire entre la tête métacarpienne et la plaque palmaire. Un récessus distal était de plus rempli dans presque tous les cas. Des récessus latéraux étaient trouvés sur les bords radial et ulnaire, entre les ligaments latéraux. Les épanchements articulaires se collectent volontiers dans le récessus dorsal qui se manifeste cliniquement. Les récessus latéraux sont cliniquement intéressants par leur proximité avec les ligaments latéraux des MCP. Les récessus décrits sont des structures normales des MCP et ne doivent pas être pris pour des éléments pathologiques.

     

后路凸侧椎板楔形截骨经肋椎关节松解胸椎间隙治疗青少年重度脊柱侧后凸

【摘要】 目的：评价经后路凸侧椎板楔形截骨经肋椎关节松解胸椎间隙矫形治疗青少年重度脊柱侧后凸畸形的安全性和早期临床效果。方法：2014年5月~2016年12月对我院15例青少年重度脊柱侧后凸患者行经后路凸侧椎板楔形截骨经肋椎关节松解胸椎间隙手术治疗,术前仅1例严重脊柱侧后凸患者行头盆环牵引。男6例,女9例,年龄13～18岁（16.1±1.6岁）。其中先天性脊柱侧后凸3例,特发性11例,神经纤维瘤病性1例。术前侧凸Cobb角82°～144°（102.5°±17.6°）,侧凸的柔韧性为6.4％～28.5％[（21.56±5.70）%];后凸50°～95°（68.1°±15.3°）,冠状位躯干偏移距离（C7中垂线与骶骨中垂线距离）2.0～6.8cm（3.40±1.37cm）。术前四肢肌力及感觉均正常。观察治疗效果。结果：椎板楔形截骨5.20±0.56个（4~6个）,松解椎间隙5.20±0.56个（4~6个）,手术时间6.1～7.9h（7.00±0.51h）,术中出血量1050～2500ml（1450.0±521.3ml）。术后侧凸Cobb角18°～40°（28.0°±6.6°）,矫正率72.5%;后凸22°～42°（27.8°±6.1°）,矫正率58.4%;冠状位躯干偏移距离0～2cm（0.85±0.74cm）,矫正率72.8%。随访25～41个月（33.1±5.4个月）。末次随访时侧凸Cobb角19°～43°（30.0°±6.9°）,矫正率70.6%;后凸22°～42°（28.6°±6.5°）,矫正率57.2%;冠状位躯干偏移距离0.2～2.3cm（1.10±0.72cm）,矫正率71.3%。无胸膜破裂,无假关节形成,无内固定断裂及松动,矫正度无显著丢失。1例患者术前骨盆牵引发生钉道感染,经局部换药及抗生素应用,2周后感染控制;1例术后第3天发生十二指肠系膜上动脉综合征,采取禁食水、持续胃肠减压、维持水电解质平衡、左侧卧位,术后2周痊愈;1例T4左侧椎弓根螺钉侵入椎管压迫神经,术后5h发生左下肢不完全性瘫痪,术后8h去除T4左侧椎弓根螺钉,术后5个月左下肢功能完全恢复。结论：采用后路凸侧椎板楔形截骨经肋椎关节松解胸椎间隙治疗青少年重度脊柱侧后凸畸形,不需要剥离椎体侧方胸膜,手术解剖层次表浅和创伤小,不仅有助于增加脊柱柔韧性,而且可提供足够的压缩和闭合空间来矫正脊柱侧后凸,能获得良好的脊柱三维矫正。