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Using the retrieved devices from one autopsy and five reoperations, the biocompatibility of explanted Talent stent-grafts was investigated to highlight the capacity of the fabric to act as an effective scaffold to regenerate a blood conduit. The autopsy device was encapsulated both internally and externally, but the capsules did not penetrate through the fabric structure. The reoperation devices showed discrete patches of compact fibrin and irregularly scattered mural thrombi. Positive staining of α-actin, tissue plasminogen activator (tPA), urokinase (uPA), urokinase receptor (uPAR), and urokinase inhibitors (PAI 1, PAI 2, PAI 3, and protease nexin), and D-dimer was more frequently identified in the autopsy sample than in the reoperation samples. This preliminary assessment shows that the stent-graft retrieved during autopsy was better healed than those explanted at reoperation.

Lumbar spinal stenosis (LSS) with neurogenic intermittent claudication is one of the most common degenerative spinal diseases in the elderly. For patients over 65 years with LSS, open decompression is the most frequent spinal surgery. One problem associated with decompression surgery is the emergence of instability, which is found in varying grades of severity. For some patients with LSS, interspinous process devices (IPD) may be a viable alternative to open decompression. The purpose of this study is to examine the destruction and changes to the interspinous and supraspinous ligament complex after percutanous IPD implantation.Biomechanical and anatomic assessments were performed on the lumbar spine (L1-L4) of 11 fresh human cadavers. The biomechanical examination assayed the force necessary to disrupt the interspinous-supraspinous ligament complex without and after implantation of an IPD. For the anatomic examination, one lumbar spine was plastinated. Serial 4-mm thick sections were cut in sagittal and horizontal planes. The macroanatomic positioning of the implants was then analysed.Biomechanics: The average age of the cadavers was 80.6±10.2 years. The minimum average disrupting forces measured 313.74±113.44 N without and 239.47±63.64 N after IPD implantation, a significant (p0.018) decrease of an average 23.7%. Anatomy: After posterolateral percutaneous IPD implantation, the posterior third of the interspinous ligament, the supraspinous ligament, the thoracolumbar fascia and paraspinous muscles bordering the inter-/supraspinous ligament complex remained undamaged.The implantation of an interspinous "stand-alone" spacer significantly minimises the force necessary to disrupt the ISL/SSL complex. After posterolateral percutaneous IPD implantation, the thoracolumbar fascia and associated musculature, which act in synergy with the ISL/SSL complex to stabilise the vertebral column, remain intact.

Individual variations in the anatomy of the knee joint have been suggested to affect the ability to functionally compensate for ACL insufficiency or to put an individual at an increased risk of ACL injury. These variations include the posterior tibial slope, the concavity of the medial tibial plateau, the convexity of the lateral tibial plateau, and the configuration of the femoral condyles. This anatomical study investigates if there is a correlation between the individual surface geometry of the femorotibial joint and the morphometry of the ACL. These data were assumed to provide evidence whether or not the functional stability of an ACL-insufficient knee may be derived from its radiographic surface geometry. Standardised measurement techniques were used to analyse the surface geometry of 68 human cadaver knees. Data were correlated with the cross-sectional area, the area of insertion and position of the footprint of the ACL and its functional bundles. Analysis revealed that there was a significant, but weak correlation between the femoral and tibial area of ACL insertion and the depth of the medial and lateral femoral condyle. No correlation was found between the surface geometry of the femorotibial joint and the cross-sectional area of the ACL. The results of this anatomical study suggest that the relationship between the joint surfaces and the morphometry of the ACL primarily is a function of size of the knee joint. Based on our results, there is no evidence that the stability of the knee can be derived from its radiographic surface geometry.

Muscle strain injuries are common in sports, and a high incidence is reported for the hamstring muscles, especially in the proximal region, where the long head of the biceps femoris muscle is most frequently affected. To look for some architectural peculiarities, which would make this muscle vulnerable, 101 legs of embalmed human cadavers were dissected and descriptively examined, morphometric data were obtained in the proximal region, and slices of plastinated specimens were microscopically examined. The 3 muscles composing the proximal hamstring complex are partly twisted around each other and possess common fibrous adhesions. Biceps femoris (BF) and semitendinosus (ST) muscles form a common head, to which the ST contributes the majority of fascicles extending 9 cm down from the ischiac tuberosity, thereby attaching to the common tendon at a remarkable pennation angle. The first BF fascicles origin from the common tendon only at 6 cm distance from the ischiac tuberosity. It is concluded that the high incidence of proximal BF strains may be a misinterpretation due to insufficient imaging and the complex architecture. It is suggested that the pennation angle at which the ST inserts to the common tendon makes this muscle especially vulnerable for strains during forced eccentric contractions.

The existing studies concerning image-free navigated implantation of hip resurfacing arthroplasty are based on analysis of the accuracy of conventional biplane radiography. Studies have shown that these measurements in biplane radiography are imprecise and that precision is improved by use of three-dimensional (3D) computer tomography (CT) scans. To date, the accuracy of image-free navigation devices for hip resurfacing has not been investigated using CT scans, and anteversion accuracy has not been assessed at all. Furthermore, no study has tested the reliability of the navigation software concerning the automatically calculated implant position. The purpose of our study was to analyze the accuracy of varus-valgus and anteversion using an image-free hip resurfacing navigation device. The reliability of the software-calculated implant position was also determined.A total of 32 femoral hip resurfacing components were implanted on embalmed human femors using an image-free navigation device. In all, 16 prostheses were implanted with the proposed position generated by the navigation software; the 16 prostheses were inserted in an optimized valgus position. A 3D CT scan was undertaken before and after operation.The difference between the measured and planned varus-valgus angle averaged 1 degrees (mean +/- SD: group I, 1 degrees +/- 2 degrees ; group II, 1 degrees +/- 1 degrees ). The mean +/- SD difference between femoral neck anteversion and anteversion of the implant was 4 degrees (group I, 4 degrees +/- 4 degrees ; group II, 4 degrees +/- 3 degrees ). The software-calculated implant position differed 7 degrees +/- 8 degrees from the measured neck-shaft angle. These measured accuracies did not differ significantly between the two groups.Our study proved the high accuracy of the navigation device concerning the most important biomechanical factor: the varus-valgus angle. The software calculation of the proposed implant position has been shown to be inaccurate and needs improvement. Hence, manual adjustment of the implant position in the software-planning step is frequently required.

The aim of our study was to investigate whether placing of the femoral component of a hip resurfacing in valgus protected against spontaneous fracture of the femoral neck. We performed a hip resurfacing in 20 pairs of embalmed femora. The femoral component was implanted at the natural neck-shaft angle in the left femur and with a 10° valgus angle on the right. The bone mineral density of each femur was measured and CT was performed. Each femur was evaluated in a materials testing machine using increasing cyclical loads. In specimens with good bone quality, the 10° valgus placement of the femoral component had a protective effect against fractures of the femoral neck. An adverse effect was detected in osteoporotic specimens. When resurfacing the hip a valgus position of the femoral component should be achieved in order to prevent fracture of the femoral neck. Patient selection remains absolutely imperative. In borderline cases, measurement of bone mineral density may be indicated.

Purpose The present study aimed at summarizing and presenting the anomalous muscles that a surgeon might encounter during axillary lymphadenectomy (AL). Methods For this purpose, both the anatomical and surgical literature was reviewed and an anatomical study on 107 cadavers was carried out. Furthermore, based on the anatomical features of the anomalous muscles that came up during our study and taking into consideration the landmarks of the AL, we further analyzed the complications that may arise from each of these muscles, along with their preoperative and intraoperative recognition and management. Results The literature review revealed that there are three supernumerary muscles that may affect the AL, namely the Langer's axillary arch, the pectoralis quartus and the chondroepitrochlearis muscles, as well as the aplasia of the lower part of the pectoralis major muscle. Eight out of the 107 (7.48%) cadavers that we dissected had such an abnormal muscle in the axilla. Specifically, the axillary arch was found unilaterally in five cadavers (4.67%) and the pectoralis quartus muscle was present unilaterally in three cadavers (2.8%). One cadaver had both an axillary arch and a pectoralis quartus muscle in the right side. The abdominal and almost the whole sternocostal portion of the pectoralis major as well the pectoralis minor muscle were absent in one cadaver (0.93%). The chondroepitrochlearis muscle was not found in any of the cadavers that we dissected. Conclusions The present study offers the necessary preoperative knowledge for recognizing these muscles during AL, avoiding thus the complications that may arise from them.

Correct placement of the tibial and femoral bone tunnel is prerequisite to a successful anterior cruciate ligament (ACL) reconstruction. This study compares the resulting radiographic femoral bone tunnel position of two commonly used techniques for arthroscopically assisted drilling of the femoral bone tunnel: the transtibial approach or drilling through the anteromedial arthroscopy portal. The resulting bone tunnel position was assessed in postoperative knee radiographs of 70 patients after ACL reconstruction. Three independent observers identified the femoral bone tunnel and determined its position in the lateral and A-P view. Differences in femoral tunnel position between transtibial and anteromedial drilling were evaluated. In the sagittal plane, significantly more femoral bone tunnels were positioned close to the reference value using an anteromedial drilling technique (86%) when compared to transtibial drilling (57%). Drilling through the transtibial tunnel resulted in a significantly more anterior position of the femoral tunnel. In the frontal plane, femoral bone tunnels which were placed through the anteromedial arthroscopy portal displayed a significantly greater angulation towards the lateral condylar cortex (50.92 degrees ) when compared to transtibial drilling (58.82 degrees ). In conclusion, drilling the femoral tunnel through the anteromedial arthroscopy portal results in a radiographic femoral bone tunnel position which is suggested to allow stabilization of both anterior tibial translation and rotational instability when using a single bundle reconstruction technique. Further studies may evaluate if there are any clinical advantages using the anteromedial portal technique.

The purpose of this study was to develop a two-dimensional density distribution pattern of the subchondral cortical bone of the radial head using subtraction densitometry. The bone density of 32 normal specimens and five with macroscopic signs of osteoarthritis was measured before and after milling off the cortical bone surface. Electronic subtraction gave the density of the subchondral cortical bone. Twenty-one specimens had areas of high bone density in the ulnar-dorsal area, five specimens showed a ventral and ulnar density maximum and six had a density maximum in the center of the radial head joint surface. No density maximum was seen in the lateral part of the joint surface. The density maximum shifted towards the dorsal-ulnar part of the radial head with decreasing total subchondral bone density. Osteoarthritic radial heads had the same distribution as non-arthritic specimens. Eccentric subchondral bone density reflects eccentric radiohumeral force transmission. This could be a reason for development of radiohumeral arthritis or the failure of radial head prostheses. Bone density patterns correlate with the incidence of radial head fractures and fracture line may be positioned between areas of high and low densities.

We have evaluated four different fixation techniques for the reconstruction of a standard Mason type-III fracture of the radial head in a sawbone model. The outcome measurements were the quality of the reduction, and stability. A total of 96 fractures was created. Six surgeons were involved in the study and each reconstructed 16 fractures with 1.6 mm fine-threaded wires (Fragment Fixation System (FFS)), T-miniplates, 2 mm miniscrews and 2 mm Kirschner (K-) wires; four fractures being allocated to each method using a standard reconstruction procedure. The quality of the reduction was measured after definitive fixation. Biomechanical testing was performed using a transverse plane shear load in two directions to the implants (parallel and perpendicular) with respect to ultimate failure load and displacement at 50 N. A significantly better quality of reduction was achieved using the FFS wires (Tukey’s post hoc tests, p < 0.001) than with the other devices with a mean step in the articular surface and the radial neck of 1.04 mm (sd 0.96) for the FFS, 4.25 mm (sd 1.29) for the miniplates, 2.21 mm (sd 1.06) for the miniscrews and 2.54 mm (sd 0.98) for the K-wires. The quality of reduction was similar for K-wires and miniscrews, but poor for miniplates. The ultimate failure load was similar for the FFS wires (parallel, 196.8 N (sd 46.8), perpendicular, 212.5 N (sd 25.6)), miniscrews (parallel, 211.8 N (sd 47.9), perpendicular, 208.0 N (sd 65.9)) and K-wires (parallel, 200.4 N (sd 54.5), perpendicular, 165.2 N (sd 37.9)), but significantly worse (Tukey’s post hoc tests, p < 0.001) for the miniplates (parallel, 101.6 N (sd 43.1), perpendicular, 122.7 N (sd 40.7)). There was a significant difference in the displacement at 50 N for the miniplate (parallel, 4.8 mm (sd 2.8), perpendicular, 4.8 mm (sd 1.7)) vs FFS (parallel, 2.1 mm (sd 0.8), perpendicular, 1.9 mm (sd 0.7)), miniscrews (parallel, 1.8 mm (sd 0.5), perpendicular, 2.3 mm (sd 0.8)) and K-wires (parallel, 2.2 mm (sd 1.8), perpendicular, 2.4 mm (sd 0.7; Tukey’s post hoc tests, p < 0.001)). The fixation of a standard Mason type-III fracture in a sawbone model using the FFS system provides a better quality of reduction than that when using conventional techniques. There was a significantly better stability using FFS implants, miniscrews and K-wires than when using miniplates.

Background: Although the anatomy and physiology of the venous circulation of the ankle and midfoot are well documented, the physiologic importance of forefoot mobility has not been reported in the literature. The question of this study was whether the first metatarsophalangeal (MTP) joint may operate, like the ankle, as a “pump” to encourage venous return. Methods: Forty-nine cadaver foot specimens were examined using dissection, plastination, vessel infiltration, and maceration, and radiographic (including venography, MRI, and magnetic resonance angiography) techniques. The anatomy and physiology were described and compared to the ankle joint. Forty patients had biphasic Doppler flow studies. Results: The major finding was the medial drainage of the plantar venous sinus, which is fibrotically bound to the joint capsule. Functional venous valves were evident distally and within fibrous vascular lumens. Mobilization of the first MTP joint led to compression and emptying of the veins. Passive mobilization of the first MTP joint led to an average flow increase of 55% ± 7 ( p < 0.0001), while active movement led to an average increase of 78% ± 7 ( p < 0.0001). Conclusions: Our described connection between the joint capsule and veins indicates a “toe-ankle pump” with a significant increase of venous blood flow during motion of the MTP joint. Possible clinical applications for an external MTP pump include anti-edema or thromboprophylactic therapy, especially in patients with foot or ankle injuries. A new toe-pump has been designed based on these results.

The purpose of this study was to describe the anatomy of the intramedullary canal of the radial neck for stem design of radial head prostheses.Radial neck measurement was performed from the proximal edge of the radial tuberosity to the distal border of the articular surface on 40 macerated proximal radii using X-rays and Optosil imprints of the intramedullary canal. Radial neck to shaft angle was measured under image intensification.The neck length was 13.3 mm (range 8.0-20.0 mm) measured on X-rays and 13.5 mm (range 9.9-18.8 mm) on Optosil imprints. Concerning the neck's intramedullary canal we obtained a minimum diameter of 9.7 mm (range 6.3-16.4 mm) on X-ray. Corresponding Optosil imprints had a mean diameter of 11.6 mm (range 6.6-18.6 mm) at their proximal end, 10.5 mm (range 5.5-16.3 mm) in the middle and a minimum of 9.8 mm (range 6.0-16.9 mm) at the distal end. Differences between left and right sides were not significant between X-ray and Optosil imprints, nor between left X-ray and right imprints and vice versa at a P-level of 0.001. Radial neck to shaft angle was 167.8 degrees (range 160.5-178 degrees ) measured under image intensification at a rotation angle of 58.6 degrees (range 50-70 degrees ) supination.Geometry of the radial neck's intramedullary canal has been described for stem design. The minimum diameter was seen at the distal end, just proximal to the radial tuberosity. A forearm rotation of 58.6 degrees to full supination should be considered during implantation of monopolar prostheses. The wide variety of lengths and diameters complicates standard prosthetic design, but ipsilateral and contralateral X-rays can be useful for preoperative stem size calculation.

The anatomical relationships of the greater occipital nerve (GON) to the semispinalis capitis muscle (SCM) and the trapezius muscle aponeurosis (TMA) were examined to identify topographic landmarks for use in anesthetic blockade of the GON in occipital neuralgia. The course and the diameter of the GON were studied in 40 cadavers (29 females, 11 males), and the points where it pierced the SCM and the TMA were identified. The course of the GON did not differ between males and females. A left–right difference was detected in the site of the GON in the TMA region but not in the SCM region. The nerve became wider towards the periphery. This may be relevant to entrapment of the nerve in the development of occipital neuralgia. In three cases, the GON split into two branches before piercing the TMA and reunited after having passed the TMA, and it pierced the obliquus capitis inferior muscle in another three cases. The GON and the lesser occipital nerve reunited at the level of the occiput in 80% of the specimens. The occiput and the nuchal midline are useful topographic landmarks to guide anesthetic blockade of the GON for diagnosis and therapy of occipital neuralgia. The infiltration is probably best aimed at the site where the SCM is pierced by the GON. Clin. Anat. 19:332–336, 2006. © 2005 Wiley-Liss, Inc.

Eighteen patients with intraarticular calcaneal fractures treated with open reduction and internal fixation and augmentation with an injectable carbonated apatite cement. Functional follow-up studies using the Zwipp Foot Score and densitometry were performed at 6-month intervals postoperatively. Histological samples of biopsies obtained at the time of hardware removal (6 months postoperatively) were also analyzed. The use of bone cement led to intermediate-term functional outcomes that were no better than those reported with conventional surgical procedures using bone graft. Patients demonstrated postoperative difficulties similar to those seen in other studies of this fracture, including pain, subtalar motion restrictions, peroneal impingement, and difficulties on uneven terrain and with toe- and heel-walking. However, compared to patients treated surgically without injectable carbonated apatite cement, full weight bearing on the affected extremity was regained at an average 4 weeks postoperatively. In addition, autogenous bone graft was not required to fill the osseous defect using this technique, minimizing morbidity and discomfort. During the present observation period of 3 years, only a slight decrease in the density of the peripheral zones of the cement block was observed. Histological examination revealed fibrous bone formation resulting from remodelling processes. Complete resorption and remodeling of the bone cement were not complete at 3 years. One patient developed a postoperative wound infection. Another displayed cement loosening secondary to failure of bony ingrowth.

Bone vascularisation has gained increased interest in relation to the blood supply of bone fragments during treatment of fractures. In the current study the pattern of vascular supply of the proximal humerus was studied in six cadavers by the corrosion technique. Furthermore, the effect of fractures on the vascular supply was also investigated. In all preparations the intraosseous arteries of the humeral head arose from the circumflex arteries, which surrounded the humerus and dispatched branches towards the proximal end. The main vessel was the branch of the anterior circumflex artery, penetrating the major tubercle in six of six cases. Due to the intraosseous arch shape of this vessel it is referred to as the arcuate artery. Besides other smaller vessels, there was also a vascular network arising from the posterior circumflex artery. Their branches penetrated medially at the cartilage bone interface in five of six preparations. The medial bone arteries appear to gain distinctive importance in humeral head fractures by their impact on the vascularisation of the fracture fragments. After disruption of the arterial supply from the arcuate artery, the vascularisation of the head fragments is most likely ensured by this group of vessels. Therefore, necessary repositioning manoeuvres during open reduction of the fracture should be conducted with care in order to preserve these arteries.

We described the anatomy of the utero-ovarian venous system in the adult postmenopausal female cadaver using casts and the von Hagen's plastination technique. To qualitatively and quantitatively evaluate the uterine vein, the utero-ovarian arcade, the ovarian vein and the ramus communicans between left and right parametrium, we injected epoxy resin into the internal iliac vein and artery and the ovarian vein and artery in six cadavers. In two cases the internal genital organs were excised before injection and in the other four after the injection and polymerization of the resin. All specimens were macroscopically examined and venous diameters were digitally measured, the average values of the measured diameters being 3.38 mm for the uterine vein, 3.71 mm for the utero-ovarian arcade, 3.49 mm for the ovarian vein, and 3.71 mm for the ramus communicans. The veins were completely filled out and could be best examined in the four cases where in situ injection was performed. We could observe that the utero-ovarian arcade is an important vein with a caliber similar to that of the ovarian and uterine veins, that there is an impressive network of venous anastomoses between the left and right parametrium and that the fallopian tubes are drained by three separate veins: internal, median, and external tubal veins. Pelvic venous congestion was present in two specimens; in one of them it was located in the region of the left uterine vein and in the other one in the region of the left ovarian vein. Given the similar average diameters of the uterine vein, ovarian vein, and utero-ovarian arcade, we assume that there is no preferential uterine or ovarian venous drainage and that the veins of the internal genital organs are behaving like a venous pool. Nevertheless, congestion can affect limited sites, which can and should be treated locally.

External fixation is a well accepted treatment option in distal radial fractures. The fixator can be used in two different ways: joint bridging or extraarticular. The extraarticular technique presumes that the fracture does not involve the radio-carpal joint and that the distal fragment is broad enough to accommodate two fixator screws. Taking into account that the majority of distal radius fractures occur in elderly female patients the question arises whether osteoporotic bone is an obstacle to extraarticular external fixation. Bone slices of 2 mm thickness were cut out of six human cadaver radii with a mean age of 76 years (from 65 to 94 years) in the sagital plane. A radiograph of each slice was digitized and the distribution of gray values measured. It was found that the radiographic density was highest at the palmar side of the distal radius in a triangular area built by the palmar lip of the radius. In this region, even in severe osteoporotic bone, strong trabeculae are visible running parallel to longitudinal axis of the radius. Fixator screws inserted into the distal radial fragment especially in an osteoporotic situation should be securely anchored in the palmar lip of the distal radius.

The anatomic development of thyroglossal tract remnants is not understood at present. For analysis of morphology and growth patterns of thyroglossal tract remnants, we used histologic whole organ serial sections to determine developmental changes through the first years of life. Larynges of 58 infants and children ages 1 month to 13 years were obtained in whole organ serial step-sections in an axial plane. The slides were stained with hematoxylin and eosin, Alcian blue, and periodic acid–Schiff stains. Altogether, 3,247 histologic slices were examined. The resulting data were then correlated with the age and sex of the specimens. We found, in 24 cases (41.3%), remnants of the thyroglossal tract or ectopic thyroid tissue. In 4 specimens (16.6%), a complete thyroglossal tract could be observed that presented a ventral path in relation to the hyoid bone with no contact with the perichondrium of the cartilage. Hormonal activity of ectopic thyroid tissue was proven in 20 cases (34.5%). Thyroid follicles were located in 2 cases (3.5%) in the hyoid bone. The thyroglossal ducts revealed a modest tendency for a left-sided pathway, whereas thyroid follicles were located more on the right paramedian side. Morphometric data on the development and structure of the thyroglossal tract and the thyroid follicles during infancy and childhood are presented. The study provides quantitative data of clinical interest that elucidate the anatomy of thyroglossal tract remnants. In addition, our investigation supports Sistrunk's operative approach for avoiding recurrences in the treatment of thyroglossal duct cysts.

The study was designed to compare the dimensions and densities of two frequently used bone donor sites with regard to placement of endosseous dental implants in microvascularly reconstructed mandibles. A total of 40 radii and of 40 fibulae were investigated. Fifty two percent of the fibulae had adequate bone volume for the positioning of four 10 mm implants, while this figure was 55% for the radii. After using the 'double barrel' technique the placement of four 10 mm implants succeeded in 87% of all the fibulae. Due to the lack of bone length required, this special technique was not possible in the radii investigated. Cortical thickness and density of bone were higher in the radii when compared with the fibulae. In each bone the central and distal parts presented the highest values of cortical thickness and density. Although the radius offers enough substantial bone for implant placement in some cases this cannot be used for clinical purpose, as only hemicortical grafts can be obtained. Otherwise the resulting donor site morbidity would be intolerable. In conclusion, our results support the clinical experience that the fibula is today's 'work horse' donor site for reconstruction of the mandible.

Summary Due to its functional significance the human skull plays an important role in biomechanical research. The present work describes a new Finite-Element model of the human neurocranium. The dry skull of a middle-aged woman served as a pattern. The model was developed using only the preprocessor (Mentat) of a commercial FE-system (Marc). Unlike that of other FE models of the human skull mentioned in the literature, the geometry in this model was designed according to functional anatomical findings. Functionally important morphological structures representing loci minoris resistentiae, especially the foramina and fissures of the skull base, were included in the model. The results of two linear static loadcase analyses in the region of the skull base underline the importance of modeling from the functional anatomical point of view.

The operative exposure of a fracture in an osteosynthesis causes disturbances in the blood supply, which often leads to a prolonged process of healing or even to healing problems, a fracture non-union, which is frequently located at the forearm. In order to damage the supplying vessels as little as possible, the position, direction and penetration of the arteries of radius and ulna are demonstrated and systematised in this study. Near the elbow arteries, coming from large adjoining vessels, penetrate the area of the capsular insertion. The nutrient arteries enter both bones in the second proximal quarter of diaphysis, at the radius from anterior to medial, at the ulna from anterior to anteroradial. Small vessels, which penetrate closely proximal to the articular surface in order to supply the distal forearm bones, come from an anastomosis between the radial, the interosseous and the ulnar arteries. In this study access vessels, choice and position of implants will be discussed.

Distal humeral fractures are rare, but severe injuries, the treatment of which is often accompanied by serious complications and its outcome strongly depends on the quality of surgical therapy. Non-union is a common entity, compromising clinical results and requiring revision surgery. Osteonecrosis is an underestimated etiologic factor in the development of non-union. The present study aims to display the distribution patterns of the arterial vessels at the distal humerus, to correlate the displayed vessels with local nutrient foramina and to disclose an endangerment of these structures by common osteosynthetic implants. Eight plastinated fresh frozen upper extremities were digitally analyzed regarding the vascular density of the cancellous bone, by calculating the ratio of area comprised by arterial vessels and the area comprised by cancellous bone on sagittal cuts of the distal humerus. Possible differences in the vascular density of the medial epicondylar region, the lateral epicondylar region and a watershed area between the epicondyles and distal to the supracondylar region were investigated. On the basis of 200 macerated humeri, the distribution pattern of cortical nutrient foramina and their anatomic relation to properly applied common distal humerus plates were documented. The data show a significantly higher density of vessels per cancellous bone in the epicondylar regions than in the watershed region (p

BACKGROUND: The two articular surfaces of the distal ulna get an important role in load transmission and stabilization of the distal radio-ulnar joint. The present study describes the morphology of the distal radio-ulnar joint surfaces in terms of the functional relationships between the shape of the ulnar articular facets and the predominant contact situation in this joint. METHODS: Besides macroscopic dissection and radiological investigation the model of the "inclined plane" has been used to simulate force transmission across the radio-ulnar joint concerning the angle between the distal and the radial articular surfaces of the ulnar head. RESULTS: The presented morphological parameters of the radio-ulnar joint surfaces verify that the transmitted forces are effective in both a radio-ulnar and an axial direction. The protection and the captaincy of this joint are limited by its great mobility. The investigations show that signs of an increased load pressure are frequently found in the joints that also show degenerative changes. As a morphological sign of the force transmission, distinct spongious trabecles are formed perpendicularly to the articular circumference in those ulnar heads that show a stolid angle between their articular facets. CONCLUSIONS: Because of the individuality of the morphological data only qualitative statements can be made both the predominant shapes of the ulnar head, in particular about the loading of its articular surfaces. The angle between its two articular facets influences the force transmission through the radio-ulnar joint as well as the spongious architecture of the subchondral bone of the ulnar head.

Background: The connective tissue body of the dorsal finger is partitioned by multiple horizontal lamellae derived from expansions of intercellular spaces. These connective fibres are involved in providing gliding spaces for the extensor apparatus, and they formed spreading rooms of infection processes. Methods: In order to describe the topographical histological and histochemical behavior of cellular and intercellular elements of the border lamellae of the dorsal aponeurosis of the fingers, a modified method of Epoxid resin embedding technique without pre-infiltration is used. Results: The bordering elements of the connective tissue lamellae described in this investigation are especially well defined in the region of the dorsal aponeurosis. The morphological examinations show that both the expansions of the intercellular space as well as defined fibrocytic cellular elements function in a manner equivalent to a synovial membrane of tendon sheaths. Conclusions: Saving or reconstructing these structures appears to be of importance in preventing for adhesive disorders of finger motion following surgical intervention in this region. © 1995 Wiley-Liss, Inc.

Objective: The aim of this study was to assess different tendon suture techniques from the perspectives of both tensile strength and early active mobilization.Methods: In this study, we implemented repairs on 40 flexor digitorum profundus (FDP) tendons, acquired from fresh frozen cadavers. The tendons were divided into 5 groups of 8 tendons each. We applied the 2-strand modified Kessler suture technique in the first group, the 4-strand Strickland suture technique in the second group, the 4-strand modified Kessler (without epitenon suture) suture technique in the third group, and the 4-strand modified Kessler (with epitenon sutures) suture technique in the fourth group. The remaining 8 intact tendons were set aside as the control group. The strength of the different tendon suture techniques were measured using the Instron® device.Results: The average tolerance strength of the first group was determined as 39.89±9.65 Newtons (N), the average tolerance strength of the second group was 39.64±9.14 N, the average tolerance strength of the third group was 50.29±11.24 N, the average tolerance strength of the fourth group was 54.47±6.83 N, and the average tolerance strength of the control group was 119±17.59 N. The tensile strength of the fourth group was significantly higher (p0.05).Conclusion: According to our findings, the tensile strength of 4-strand sutures, with or without epitenon sutures, are significantly higher than the tensile strength of 2-strand sutures. All suture techniques applied had sufficient tensile strength to promote early mobilization., Amaç: Bu çalışmada farklı tendon dikiş tekniklerinin çekme dayanımı ve erken aktif hareket açısından uygunluğu değerlendirildi. Çalışma planı: Taze donmuş kadavra ellerinden elde edilen 40 fleksör digitorum profundus (FDP) tendonuna onarım uygulandı. Tendonlar 8’erlikten 5 gruba ayrıldı. Birinci gruba, proksimalden kilitli 2 kollu modifiye Kessler, ikinci gruba 4 kollu Strickland, üçüncü gruba 4 kollu modifiye Kessler (epitenon dikişsiz), dördüncü gruba da ise 4 kollu modifiye Kessler (epitenon kişli) dikiş teknikleri uygulandı. Geri kalan 8 adet tendon ise kontrol grubunu oluşturdu. Farklı tendon dikiş tekniklerinin gücü Instron® cihazı ile ölçüldü. Bulgular: Birinci grubun ortalama dayanma gücü 39.89±9.65 Newton (N), ikinci grubun ortalama dayanma gücü 39.64±9.14 N, üçüncü grubun ortalama dayanma gücü 50.29± 11.24 N, dördüncü grubun ortalama dayanma gücü 54.47±6.83 N, kontrol grubunun ortalama dayanma gücü ise 119±17.59 N olarak saptandı. Bu sonuçlara göre dördüncü grubun çekme dayanımı birinci gruba göre ve üçüncü grubun çekme dayanımı birinci gruba göre anlamlı şekilde yüksek bulundu (p0.05). Çıkarımlar: Bulgularımıza göre epitenon dikişli olsun veya olmasın 4 kollu dikişlerin çekme dayanımı 2 kollu dikişlerin çekme dayanımına göre istatistiksel açıdan anlamlı olarak daha yüksektir. Uyguladığımız tüm dikiş teknikleri erken hareket verebilmek için yeterli güce sahiptiler.

It is generally accepted that vessel cannulation is technically more difficult and results in more complications in neonates. A sound anatomical knowledge of the inguinal area is therefore important in the selection of appropriately sized central line catheters as well as the approach to central vessel access. Eleven stillborns were investigated. Birth weight (mean: 2,414 g, 900-4,100 g) and gestational age (mean 34 1/7 weeks', 27 6/7-42 1/7) varied within normal range. The outer diameters of the femoral artery (FA), femoral vein (FV), and great saphenous vein (GSV) were determined. The distance between the anterior superior iliac spine and the pubic tubercle was set as 100% and the vessel intersection points were calculated as percentage values of the inguinal ligament length, starting at the iliac spine. The FA has a diameter of 1.9 ± 0.5 mm without correlation to gestational age. The FA crosses the inguinal ligament centrally. The FV has a diameter of 3.1 ± 1.0 mm and does have correlation to gestational age. The FV crosses the inguinal ligament at 63-64%. The GSV has a diameter of 1.4 ± 0.7 mm. Its point of intersection at the level of the inguinal ligament is 68-70%. We conclude that cannulation of the femoral artery or vein should not be performed too far (1 cm) from the inguinal ligament. The course of the GSV is not suitable for catheter insertion.

The lateral femoral cutaneous nerve (LFCN) can be at risk during, for example, the insertion of pins in the anterior superior iliac spine (ASIS) during external fixation of the pelvis, total hip arthroplasty through a direct anterior approach, open surgery for impingement in the hip through an anterior approach, and periacetabular osteotomy. During surgery, the surgeon usually assumes the location of the LFCN by using the ASIS as a landmark.We investigated (1) whether there is any relationship between the LFCN and the ASIS and (2) the anatomy of the LFCN at the lateral border of the psoas major.Using 25 formalin-fixed cadavers, we determined the location of the LFCN emergence point as above, same level with, or below the iliac crest (IC). We measured the distances between the LFCN emergence point and the crossing of the IC and psoas major, ASIS, and pubic tubercle. We measured the distances between the ASIS and pubic tubercle (AB) and the ASIS and the point where the LFCN crossed the inguinal ligament (AC) and then calculated AC/AB.The LFCN was below the IC on 19 sides, at the same level on 13 sides, and above on 12 sides. The distances were -0.98 ± 5.57 cm to the IC, 12.39 ± 2.67 cm to the ASIS, and 17.76 ± 3.33 cm to the pubic tubercle. AB was 13.11 ± 1.08 cm, AC 2.95 ± 2.01 cm, and AC/AB 0.22 ± 0.16.The LFCN may emerge from the lateral border of the psoas major above or below the IC. The AC/AB ratio can help surgeons to find the LFCN in patients with different body types.

BACKGROUND A distal femur nail with fixed-angle locking screws intends to combine the advantages of angular stability and intramedullary stabilization in extraarticular distal femur fractures. The goal of this study was to analyze whether the locked compression distal femur nail (LCN) was biomechanically more stable than a conventional standard distal femur nail (CN). METHODS Both nails were compared on a series of 10 matched pairs of human femora. After setting a distal femur defect fracture, the intramedullary stabilized femur was axially loaded starting from 100 N, increasing in steps of 100 N after every 200 cycles with a triangular frequency of 1 Hz, until a predefined point of failure was reached. RESULTS The two types of nails showed no significant difference in terms of maximum tolerated load, maximum number of cycles repeated, or axial deformation of the bone-implant construct. The mean load at failure was 2,954 N for the CN and 2,483 N for the LCN. The mean axial deformation for the conventional (14.8 mm) and locked compression nail (15.3 mm) did not differ significantly. Mode of failure was a bony fracture in all specimens predominantly involving the proximal femur. CONCLUSIONS No significant difference in stability between the two compared implants could be demonstrated. The LCN showed comparable characteristics under cyclic axial loading as the conventional distal femur nail. No migration into the articular space or implant failure was observed.

The first metacarpal bone is stressed by a dorsopalmar bending, as proved by radiological studies. In case of a trapeziometacarpal arthrosis the subluxated metacarpal bone is subjected to an increased bending stress. Functional adaptation of the bone leads to an augmented cortical thickness. The dorsopalmar diameter of the medullary cavity decreases. After the implantation of the prosthesis the magnitude of bending stress again decreases and bony resorption occurs. This explains the radiolucent lines at the bone-cement interface of the metacarpal component.

Central venous catheterization is widely used in neonatology. Although ultrasonic guidance for central venous catheter placement is available, complications occur significantly more frequently in infants, especially neonates, than in adults. This study seeks to determine the characteristics, topographical conditions, regional relationships, and diameters of the venous structures of the upper extremity and the thoracic central venous system in extremely small preterm neonates (mean: 900 g). Nine formaldehyde-fixed preterm stillborns were prepared (mean 27 2/7 weeks' gestational age). The anatomical preparation involved the complete thoracic wall, neck and shoulder region, and preparation of the upper extremities. It was shown that the course of the internal jugular vein can be influenced by rotation of the head. Maximum head rotation (80°) to the contralateral side leads the internal jugular vein to overlap the common carotid artery and sharpens the confluence angle of the internal jugular into the brachiocephalic vein. We propose that this has the potential to result in dislocation of the catheter. Less rotation of the head (

Precise implantation of hip resurfacing arthroplasty by imageless computer navigation. Hence a malalignment of the femoral component, leading to early loss of the implant, can safely be avoided.Coxarthrosis in patients with normal bone mineral density; only minor deformity of the femoral head that enables milling around the femoral neck without notching.Osteoporosis; large necrosis of the femoral head; metal allergy; small acetabular seat and corresponding wide femoral neck, leading to needless acetabular bone loss; pregnancy, lactation.Hip joint exposure by a standard surgical approach, bicortical placement of a Schanz screw for the navigation array in the lesser trochanter. Referencing of the epicondyles, the four planes around the femoral neck and head by use of the navigation pointer. Planning of the desired implant position on the touchscreen of the navigation device; a guide wire is inserted into the femoral head and neck using the navigated drill guide; navigated depth drilling is performed. The femoral head is milled using the standard instruments. The acetabular bone stock is prepared with the conventional instrumentation; high-viscosity cement is finger-packed on the reamed head and the femoral component is inserted. Hammer blows should be avoided to prevent microfractures. Verification of the implant position by the navigation device; displacement of the Schanz screw; joint reposition and closure of the wound.Standard postoperative management after hip arthroplasty.The comparison of 40 navigated and 32 conventionally implanted ASR prostheses resulted in a significant reduction of outliers by use of computer navigation (navigated procedures: one outlier, conventional procedure: nine outliers; p0.001). Accuracy of the navigation device was tested by analysis of planned and verified implant position: CCD angle accuracy was 1 degrees , antetorsion accuracy was 1 degrees , and offset accuracy was 1.5 mm. An ongoing computed tomography-based anatomic study proved a varus-valgus accuracy of the navigation device of 1 degrees .

Thoracostomy tubes are widely used in neonatology. Complications occurred significantly more frequently in infants, especially neonates, than in adults. Principally, the access is the modified Buelau position which takes place in the anterior axillary line at the 4th or 5th intercostal space above the margin of the ribs.This study seeks to determine the characteristics and topographic conditions of the anatomical structures at the ventral and lateral thoracic wall in the preterm and term neonate.Fifteen formalin-fixed stillborns were prepared (nine male, six female, 28-43 weeks gestational age).The anatomical preparation involved the complete thoracic wall region.In all preparations, a venous vessel was detected at the lateral wall and was identified as v. thoracoepigastrica without accompanying artery. Arteria (a.) and vena (v.) thoracica interna were regularly found close to the sternal plate on both sides between rib and fascia. With increasing gestational ages the course of the v. thoracoepigastrica varied significantly between the left and right thoracic wall. It was demonstrated that the v. thoracoepigastrica regularly arose within the abdominal or thoracic subcutaneous fat and drained into the v. subclavia. The variance between its course was almost 5-12 mm to the lateral or medial side. At both thoracic sides, no other organs or organ structures except lung parenchyma could be detected when using the Buelau position.The anterior to midaxillary line between the 4th or 5th intercostal space (Buelau position) is safe for the use of thoracostomy tubes in preterm and term infants.

Background: The influence of the knee angle on plantarflexion moments after Achilles tendon repair has yet to be analyzed. It was hypothesized that flexion of the knee joint will disproportionately influence isometric plantarflexion moments after Achilles tendon repair. Materials and Methods: Isometric plantarflexion moments and functional heel rise performance were retrospectively assessed in 32 patients at a mean follow-up of 36.9 (±17.83) months after open or percutaneous repair of acute Achilles tendon rupture. Plantarflexion moments were measured with the knee joint in 0, 30, and 60 degrees of flexion and the ankle joint positioned in neutral, 15 degrees plantar flexion and 15 degrees dorsiflexion. Data were compared between the involved and the noninvolved leg as well as between open and percutaneous repair. Results: Flexion of the knee had no significant effect on isometric plantarflexion moments in either the involved or the noninvolved leg, while at any knee angle, plantarflexion moments decreased from dorsiflexion to plantar flexion. In accordance, dynamic heel rise performance revealed no significant strength deficits between the involved and the noninvolved limb. No overall differences in plantarflexion strength were observed between open and percutaneous Achilles tendon repair. Conclusion: The flexion angle of the knee had no influence on plantarflexion moments when comparing the involved with the noninvolved leg after open or percutaneous Achilles tendon repair. Weakness of plantarflexion after open or percutaneous Achilles tendon repair is determined by the position of the ankle joint rather than by the flexion angle of the knee.

Aim The aim of the present study was to compare the primary fixation stability and initial fixation stiffness of two established fixation techniques, the tension band wiring technique and interfragmentary screw fixation, with a mini-screw fragment fixation system in a model of transverse patella fracture. It was hypothesised that the biomechanical loading performance of the fragment fixation system would not significantly differ from the loading characteristics of the two established methods currently investigated. Materials and methods Ninety-six calf patellae were used in this biomechanical model. A standardized transverse patella fracture was induced and three different fixation methods, including the modified tension band wiring technique, interfragmentary screw fixation, and the mini-screw fragment fixation system, were used for fragment fixation. Specimens were mounted to a loading rig which was secured within a material testing machine. In each fixation group, eight specimens were loaded to failure at a simulated knee angle of either 0° or 45°. Another eight specimens were submitted to a polycyclic loading protocol consisting of 30 cycles between 20 N and 300 N at a simulated knee angle of 0° or 45°. The residual displacement between the first and the last cycle was recorded. Differences in the biomechanical performance between the three fixation groups were evaluated. Results No significant differences between the three fixation groups were observed in the parameters maximum load to failure and linear fixation stiffness with monocyclic loading. Specimens being loaded at 45° showed significantly lower maximum failure loads and linear stiffness when compared with 0°. During polycyclic loading, no significant differences in the residual displacement were observed between the groups at 0° loading angle, while at 45°, residual displacement was significantly higher with tension band fixation when compared with interfragmentary screw fixation or the fragment fixation system. Conclusion The biomechanical performance of the fragment fixation system was comparable to interfragmentary screw fixation and superior to the tension band wiring technique. Given the advantages of a system which provides interfragmentary compression and which simplifies fracture fixation after open or closed reduction, we believe the fragment fixation system to be an adequate alternative in the osteosynthesis of transverse patella fractures.

Side-to-side comparison of anatomical or functional parameters in the evaluation of unilateral pathologies of the human knee joint is common practice, although the amount of symmetry is unknown. The aim of this study was to test the hypothesis that there are no significant differences in the morphometric knee joint dimensions between the right and the left knee of a human subject and that side differences within subjects are smaller than intersubject variability. In 20 pairs of human cadaver knees, the morphometry of the articulating osseous structures of the femorotibial joint, the cruciate ligaments, and the menisci were measured using established measurement methods. Data were analyzed for overall side differences and the ratio between within-subject side differences and intersubject variability was calculated. In three out of 71 morphometric dimensions there was a significant side difference, including the posterior tibial slope, the anatomical valgus alignment of the distal femur, and the position of the femoral insertion area of the ACL. In two additional parameters, including the cross-sectional area of the ACL and PCL, within-subject side differences were larger than intersubject variability. In general, there was a positive correlation in morphometric dimensions between right and left knees in one subject. It is concluded that a good correlation in the morphometric dimensions of a human knee joint exists between the right and the left side. This study supports the concepts of obtaining morphometric reference data from the contralateral uninjured side in the evaluation of unilateral pathologies of the knee joint.

PubMedID: 17632483 Objective Lingual nerve damage is a common complication during oral and maxillofacial surgery procedures to the third molar region. The anatomy of the lingual nerve is variable, therefore the precise knowledge of anatomy of this nerve is important for decreasing the damage risk. The purpose of this study was to determine the position and the shape of the lingual nerve in the third molar region using radiographic imaging.Setting The Anatomy Department of Cologne University in Germany.Materials and Methods Firstly, an anatomic dissection of the lingual nerve in the third molar region was done on 10 whole heads and one sagittal hemisection head specimen of adult cadavers. After marking the nerve, x-ray films were taken. Vertical and horizontal measurements were made from the radiographs with an electronic digital caliper.Results The mean vertical and horizontal distances of the nerve to the lingual crista and lingual plate of the mandible were found to be 9.5 ± 5.2 mm and 4.1 ± 1.9 mm respectively. Additionally, of the 21 lingual nerves examined, 17 (81%) were round and 4 (19%) were flat.Conclusions The results reflect the relationship of the nerve to this area and may help the clinician to avoid the damage risk. © 2007 Nature Publishing Group.

PubMedID: 16374570 The first tarsometatarsal (TMT) joint has a complex role in regulating joint pressure in the midfoot. Despite its importance, there have been only a few studies of the functional morphology and biomechanical function of this joint. Here we report about the densitometric pattern of the subchondral bone layer of the articulating elements of the human first TMT joint. We studied dry bones of the first metatarsal and medial cuneiform bones in 64 human cadavers to establish the pattern of the density distribution and to correlate it with the biomechanical function of the joint. The articular surfaces of both the bones were analyzed planimetrically. Half of the specimens (n=32) were sectioned in the sagittal plane and the other 32 articulations were in the transverse plane. In all the sections, the subchondral bone density of the first TMT joint was measured. We found that in sagittal slices the dorsal area of the lateral parts and intermediate parts in females and the dorsal area of the lateral parts, the medial parts and intermediate parts in males were denser than the plantar area and that its density decreased towards the plantar area. The dorsal parts of transverse slices in males were the densest and its density decreased towards the plantar part. In the dorsal, middle and plantar parts in females in transverse slices, the lateral and intermediate areas were denser than the medial areas (P

Neutral sphingomyelinases sphingomyelin phosphodiesterase (SMPD)2 and -3 hydrolyze sphingomyelin to phosphocholine and ceramide. smpd2 is expressed ubiquitously, and smpd3 is expressed predominantly in neurons of the CNS. Their activation and the functions of the released ceramides have been associated with signaling pathways in cell growth, differentiation, and apoptosis. However, these cellular responses remain poorly understood. Here we describe the generation and characterization of the smpd3 – / – and smpd2 – / – smpd3 – / – double mutant mouse, which proved to be devoid of neutral sphingomyelinase activity. SMPD3 plays a pivotal role in the control of late embryonic and postnatal development: the smpd3 -null mouse develops a novel form of dwarfism and delayed puberty as part of a hypothalamus-induced combined pituitary hormone deficiency. Our studies suggest that SMPD3 is segregated into detergent-resistant subdomains of Golgi membranes of hypothalamic neurosecretory neurons, where its transient activation modifies the lipid bilayer, an essential step in the Golgi secretory pathway. The smpd3 – / – mouse might mimic a form of human combined pituitary hormone deficiency.

This study investigates the topographical relationship of the lateral femoral cutaneous nerve (LFCN) to the anterior iliac crest and its clinical relevance in the context of bone graft harvesting. In the anatomical part of the study, LFCN was dissected and its course investigated in 34 human formalin-embalmed cadavers. In the clinical part, data of patients who underwent an iliac crest bone grafting procedure were collected and analysed. The obtained results were then compared with the results of other investigators published in the medical literature. From 34 nerves, the lateral branch of 1 LFCN (2.9%) crossed the anterosuperior iliac spine (ASIS) prominence at a distance less than 5mm superolaterally from the most anterior point of the spine. All other nerves ran below the inguinal ligament with an average distance of 14.6mm in the inferomedial direction from the spine. In 4 out of 298 patients (1.3%) who underwent harvesting of monocortical bone grafts from the inner table of the ilium, sensory disturbances in the dermatome of LFCN were observed. After a maximum period of 12 months all sensory disturbances resolved so that no case of permanent sensory impairment was recorded. The relatively low incidences of iatrogenic LFCN damage can be attributed to a standardized surgical concept which employs a lateral incision and layer by layer dissection to the periosteum/iliacal fascia level in order to identify the nerves potentially crossing the iliac crest above the ASIS.

The purpose of this study was to evaluate functional ultrasound as a tool for detecting an ulnar collateral ligament injury of the thumb. The feasability of using ultrasound for imaging the thumb joint space was tested in a pilot study, using ultrasound and dissection in 14 cadaveric hand specimens. To test this method clinically, both metacarpophalangeal joints of the thumb in 461 healthy volunteers were examined using ultrasound (11 MHz) under radial stress. The distance between the innominate tubercle of the first metacarpal head to the proximal phalanx was measured. The mean distance between the first metacarpal head and the proximal phalanx (n = 461) was 4.5 mm (standard deviation, 0.65 mm) on the right side and 4.6 mm (standard deviation, 0.61 mm) on the left side. These data were compared with data of 25 patients with an operative diagnosis of rupture of the ulnar collateral ligament of the thumb. The difference in joint space between the injured and uninjured sides was 2.25 mm (standard deviation, 0.46 mm). The metacarpophalangeal joint space can be reproducibly detected on high-frequency ultrasound. An increased gap seen on ultrasound is indicative of a rupture of the ulnar collateral ligament of the thumb.

The selective rupture of the calcaneocuboid ligament is extremely rare and frequently misdiagnosed. This study tries to clarify the mechanism, classification and treatment of this entity. The necessity of radiographs with varus stress and in certain cases of computer tomography (CT) and magnetic resonance imaging (MRI), beside the routine antero-posterior and lateral views, is emphasized. Thirteen cases out of five-hundred-twenty-one sprain injuries of the ankle are described, classified and the therapy discussed: If on varus stress radiographs, there is a calcaneocuboid angle 10 degrees with or without a small bony flake of the ligament insertion (type 2) should primarily be treated with a shoe cast for 6 weeks; if there are persistent symptoms a secondary peroneus brevis tendon graft is recommended. A calcaneocuboid angle >10 degrees with a big flake (type 3) should be treated by open reduction and refixation of the ligament. Complex injuries (type 4) are characterised by cuboid compression fracture and ligament rupture.

An in vitro experiment was designed to identify whether tensile force on different triceps surae components would result in nonhomogenous force distribution across the human Achilles tendon. Medial tendon forces were significantly higher than lateral (23.2 ± 6.6%; P ≤ 0.05) when only the gastrocnemius medialis was subjected to force. Lateral forces were significantly higher when both gastrocnemii (30.6 ± 16.5%) or all three muscles (20.7 ± 10.9%) were loaded. Experimental identification of force concentrations in the human Achilles tendon contributes to the understanding of the origin of its injury.

The morphologic development of the human larynx during the first years of life is poorly understood to date. This study used plastinated whole organ serial sections to determine the growth and structure of the infant larynx. The larynges of 43 children 1 to 60 months old were plastinated. Whole organ serial sections were obtained by cutting the resulting specimen with a diamond band saw. The slices were then submitted to computer-assisted morphometric investigation. We found that the subglottic airway rapidly increases in size during the first 2 years of life. Further growth follows a linear mode. The relative proportion of the mucosal lining decreases likewise. In contrast to that in adults, and comparable to that in most mammals, the cartilaginous glottis accounts for 60% to 75% of the vocal folds' length at

The study was designed to compare dimension and density of four frequently used bone donor regions (the iliac crest, the lateral border of the scapula, the radius and the fibula) with regard to placement of endosseous dental implants in microvascular mandibular reconstruction. The first part of the study reports on the results of bone dimension and density findings for iliac crest and scapula bone. Nearly all of the iliac crests had adequate dimensions for the positioning of four 10 mm implants. In 63% of the scapulae, it was possible to place four 10 mm implants. In the case of the scapula, half of the female subjects lacked enough available bone for the insertion of four 10 mm implants because of their inadequate width. Bone density and cortical thickness was found to be similar in the iliac crest and scapula. Age and side do not have an important influence on cortical bone dimensions and density. In contrast to the iliac crest, the lateral margin of the scapula astonishingly showed increasing values for bone density and increasing thickness of the cortex. Analogical advanced biological age works in conformity with the scapula flap. The results could, together with other clinical criteria, contribute to the choice of the best individual alternative in mandibular reconstruction.

Summary Accessory ossifications in the ulno-carpal transition such as ossa styloidea or triangularia represent a rare finding, especially among younger individuals. The present results of radiological and morphological investigations show that up to 50% of the ossa are located palmar to the styloid process. Most of them have a sharply bordered contour and are less than 10 mm in length. An aetiological classification of accessory ossifications in the distal epiphyseal region is only possible when an obvious case history is available. Accessory skeletal elements are present among elderly individuals as a result of sclerotic alterations of the ulno-carpal joint elements. Among younger individuals, however, they point to a pathological aetiology and can therefore assume clinical and diagnostic relevance in cases involving inflammatory rheumatic and traumatic alterations accompanied by vague discomfort in the proximal wrist region.

In the present study saddle joints of the thumb and neighboring joints of 100 anatomic specimens are examined with regard to radiological and macroscopic arthrotic alterations. Comparisons of radiological and macroscopic findings demonstrate that early arthrotic articular alterations cannot be diagnosed radiologically. Almost half of the hands examined displayed arthrotic lesions in the saddle joint of the thumb, whereas the trapezoido-scaphoidal and trapezio-scaphoidal joints are each affected in one third. Hands with manifest thumb saddle joint arthrosis are accompanied by arthrotic alterations of the joints between the scaphoid, trapezium and trapezoid in two-thirds of the cases. In the remaining radial intercarpal joints, no macroscopic evidence can be ascertained of arthrotic alterations. Among the processes discussed as causal factors of simultaneous incidence of scaphoidal and carpo-metacarpal arthroses, the architecture of the osseous carpus, the individual expression of the scaphoid bone and poly- or secondary arthrotic processes are important.

Background: The extensor apparatus of the thumb displays obvious structural variations in its proximo-distal expanse. Its associated tissue comes in close relation to the dorsal aponeurosis that have varying topographical relationships to the extensor apparatus of the thumb. This region is especially important as the location of pathological and repair processes. Methods: In this anatomical study using a modified embedding technique a histological description of the fibrous architecture of the dorsal aponeurosis and the peritendinous connective tissue body of the thumb is presented. Results: The dorsal connective tissue of the thumb forms different layers of collagen lamellae as a peritendinous system around the tendons of the long and short extensor tendons of the thumb. This peritendinous laminar system as the main part of the dorsal aponeurosis is connected with both the capsular and the retinacular ligaments of the thumb. Conclusions: It will be shown that the structural variations of the dorsal aponeurosis and peritendinous connective tissue are an expression of different topographical zones of stress along the lines of a balanced musculofibrous stabilization of the interphalangeal joint of the thumb. The expansions in the peritendinous intercellular space act as defined gliding spaces or clefts of the extensor apparatus. © 1995 Wiley-Liss, Inc.

Radiographs are used in a wide variety of musculoskeletal examinations. Special procedures are required to improve image quality. We report a new radiologic technique that uses monochromatic molybdenum K alpha-radiation together with secondary digital color-coding to produce well contrasted images of supporting tissue. In order to investigate the diagnostic capability of this approach we studied specimens of the intervertebral disc, harvested from cadavers undergoing chemonucleolysis following an injection of chymopapain. Radiographs of the specimen taken using a Mo X-ray tube with a zirconium filter were scanned into a computerised image-processing system and color-coded. This method improves resolution and contrast in the images and allows the differentiation of morphologic changes.

In a comparative, experimental examination of 60 human cadaver radii, the stability of various, widely used internal fixation procedures of a distal radius fracture loco typico using a dorsal wedge was determined. The use of 2.5-mm Kirschner wires (K-wires) delivered a 10% greater stability than 1.8-mm K-wires. The 2.7-mm polylactide rods achieved a slightly greater stability than 1.8-mm K-wires under accurate pinning conditions. Polylactide rods (35 mm length, 2 mm diameter) and polyglycolide rods (60 mm length, 2 mm diameter) proved to be 20% less solid than 1.8-mm K-wires and almost 45% less than plate fixation. The short polylactide pins, however, did not have enough hold in the proximal cortical bone. The 2.7-mm polylactide rods (60 mm length) complied with the stability prerequisites necessary for comparable substitution for K-wires in distal radius fractures.

Repair of meniscal tears occurs best in the region of the capsular attachment. The further the tear from the site of capsular attachment, the less the vascularity, and healing becomes dubious. For an evaluation of healing in the poorly vascularised zone of the meniscus a histological study was performed in rabbits with standard longitudinal incisions in the posterior horn of the left medial menisci. In addition a biomechanical investigation of scar strength was performed. Three groups of animals were studied: group 1 were allowed to heal spontaneously, group 2 were sutured and group 3 were treated with fibrin glue. After 6 weeks, macroscopically, 4 out of the 10 menisci in groups 1 and 3 exhibited incomplete scar formation, whereas all menisci in group 2 looked well. This result fell short of statistical significance because 2 menisci in group 2 had to be excluded due to faulty localisation of the standard injury. In all groups the scars contained fundamental elements of healing, such as fibroblasts, blood vessels and fibrous material. Repair seemed to be significantly influenced by the proliferating synovial membrane. Histologically there was no difference between group 1 and 3. In both groups the lesions were filled with a broad strip of reparative tissue mostly consisting of plexiform collagenous fibres. Although the appearance of the menisci in group 2 was similar, the scar tissue was distinctly thinner due to the close adaptation of the wound margins, and the vascularity seemed better. In all specimens the tissue located towards the free rim of the meniscus showed signs of degeneration.(ABSTRACT TRUNCATED AT 250 WORDS)