Innervation of the elbow joint: Is total denervation possible? A cadaveric anatomic study.

The aim of this anatomical study was to find out if total denervation of the elbow joint is technically feasible. The endbranches of the brachial plexus of eight fresh-frozen upper arm cadavers were dissected with optical loupe magnification. All major nerves of the upper limb (except the axillary and the medial brachial cutaneous nerve) give some terminal articular endbranches to the elbow.

Endoscopically assisted core decompression in avascular necrosis of the femoral head.

The authors have used bone endoscopy (medulloscopy) to improve the accuracy of the conventional technique for core decompression and grafting in 36 hips with avascular necrosis of the femoral head. Endocopy was found to facilitate debridement of the necrotic bone and to decrease the risk of perforation of the cartilage during debridement. The endoscopy-assisted technique failed, however, to improve the final outcome of core decompression and grafting in more advanced stages of osteonecrosis.

The role of the transverse carpal ligament in carpal stability: an in vitro study.

A biomechanical in vitro study was performed on 16 fresh frozen cadaver forearms to investigate the role of the transverse carpal ligament (TCL) in carpal stability. The distance between the scaphoid and hamate was measured, as a reference for the length of the TCL. Distances were recorded in both loaded and unloaded conditions after gradual sectioning of the transverse carpal ligament, the palmar scapholunate, long radiolunate ligament and radioscapholunate ligament.

Mosaic versus regulation development in avian blastoderms depends on the spatial distribution of Rauber's sickle material.

We describe how to prepare unincubated avian eggs to obtain a greater number of clearly visible Rauber's sickles for experimental embryology. After hemi-sectioning of unincubated chicken (Gallus domesticus) blastoderms and cultivating both halves in vitro, two kinds of development can be discerned: (1) when the unincubated blastoderms were hemi-sectioned according to the plane of bilateral symmetry, going through the middle region of Rauber's sickle, we obtained two hemi-embryos (a left and a right one). Each contained a half primitive streak, localized at the cut edge (starting from the most median part of Rauber's sickle) giving rise to a half mesoblast mantle and half area vasculosa, thus indicating mosaic development (each part of the whole fertilized egg would be able to form independently on its own).

Validation of the lesser sigmoid notch of the ulna as a reference point for accurate placement of a prosthesis for the head of the radius: a cadaver study.

We undertook a study on eight arms from fresh cadavers to define the clinical usefulness of the lesser sigmoid notch as a landmark when reconstructing the length of the neck of the radius in replacement of the head with a prosthesis. The head was resected and its height measured, along with several control measurements. This was compared with in situ measurements from the stump of the neck to the proximal edge of the lesser sigmoid notch of the ulna.

Early steps in neural development.

We studied early neurulation events in vitro by transplanting quail Hensen's node, central prenodal regions (before the nodus as such develops), or upper layer parts of it on the not yet definitively committed upper layer of chicken anti-sickle regions (of unincubated blastoderms), eventually associated with central blastoderm fragments. We could demonstrate by this quail-chicken chimera technique that after the appearance of a pronounced thickening of the chicken upper layer by the early inductive effect of neighboring endophyll, a floor plate forms by insertion of Hensen's node-derived quail cells into the median part of the groove. This favors, at an early stage, the floor plate "allocation" model that postulates a common origin for notochord and median floor plate cells from the vertebrate's secondary major organizer (Hensen's node in this case).

Histological evaluation of autophagic cell death in calcified aortic valve stenosis.

Background And Aim Of The Study: Calcification in aortic valves is the most common valvular lesion in western populations. This event is correlated with cellular degeneration in the valvular cusps, although there is no exact evidence how these cells die: this requires further exploration.

Methods: Twelve human severely calcified aortic valves obtained during cardiac surgery were studied by semi-quantitative analysis, and results compared with data from 12 human control aortic valves obtained during autopsy.

Risk factors for congestive heart failure after aortic valve replacement with a Carpentier-Edwards pericardial prosthesis in the elderly.

Background And Aim Of The Study: Congestive heart failure (CHF) after aortic valve replacement (AVR) is an important cause of morbidity. The study aim was to identify preoperative risk factors for CHF.

Methods: A total of 500 consecutive patients (271 males, 229 females; median age 73 years; range: 71-77 years) was investigated retrospectively.

Timing of aortic valve replacement in elderly patients with symptomatic aortic valve disease using outpatient clinical parameters.

Objective: To determine by how far worsening outpatient clinical parameters can affect outcome after aortic valve replacement, in patients with preserved left ventricular function and symptomatic aortic valve disease.

Patients And Methods: Five hundred patients with aortic valve disease underwent aortic valve replacement using a bioprosthesis. In 348 patients, another procedure was added.

Current status of proximal gastric vagotomy, one hundred years after Pavlov: is it finally history?

One hundred years ago, the role of the vagal nerve in gastric acid production was established. After the second World War, this paradigm served as the basis of treatment of peptic ulcer disease by pharmacological or surgical means. A remarkable parallelism between the developments of both approaches was observed in the 1970s.

Smooth muscle cell hypertrophy in varicose veins is associated with expression of estrogen receptor-beta.

Varicose veins are characterized by dilated and thickened vein walls. This study examined whether the changes that occur in varicose veins are associated with smooth muscle cell (SMC) hypertrophy, cellular proliferation or apoptosis. Moreover, the association between SMC hypertrophy and the expression of the estrogen receptor-beta (ERbeta) was investigated.

Anatomical considerations of the radius.

Most radial head prostheses do not seem to be based on anatomic data. This may be due partly to the great variation of radial morphology. More importantly, few articles report on the dimensions of the radius.

Risk factors and survival after aortic valve replacement in octogenarians.

Background And Aim Of The Study: The study aim was to determine if aortic valve replacement in octogenarians is still rewarding.

Methods: Between 1986 and 2000, 500 patients received a Carpentier-Edwards pericardial valve in the aortic position. Of these patients, 348 also underwent coronary artery bypass grafting (CABG).

Effect of prior malignancy on survival after cardiac surgery.

Background: The number of patients with a previously treated tumor, needing cardiac surgery is increasing. Whether this operation in these patients is justified is determined by the long-term outcome.

Methods: Of 8620 patients referred for cardiac surgery, 205 had a documented malignant tumor.

Induction and improved embryonic development by the nucleus of Pander in associated avian blastoderm parts: influence of delta or gamma ooplasm.

After placing in vitro, central subgerminal ooplasm (containing a central nucleus of Pander) from a quail germ disc of a prelaid egg (before symmetrization) on the upper layer of an isolated chicken antisickle, we observed the induction of a radially oriented preneural plate (without interference of chordamesoblast). This observation suggests the primary existence during the period of symmetrization in utero of an until now unknown temporospatially linked "vertical" effect, emanating from the nucleus of Pander, on the parallel (pre)neural plate anlage forming part of the area centralis in the overlying blastoderm. For comparison, we "sandwiched" in vitro a quail sickle endoblast fragment between the deep side of the upper layer of an isolated chicken antisickle region and a central subgerminal ooplasmic mass.

Rauber's sickle and not the caudal marginal zone induces a primitive streak, blood vessels, blood cell formation and coelomic vesicles in avian blastoderms.

By using the quail-chicken chimera technique, we studied the reactivity and the eventual developmental or inducing capacities of the avian caudal marginal zone (in comparison with Rauber's sickle), when associated in vitro with different avian blastoderm components. If a fragment of quail sickle endoblast is placed on the caudal marginal zone of a whole unincubated chicken blastoderm, then a secondary miniature embryo will develop in this caudal marginal zone. The primitive streak and accompanying neural plate of the secondary embryo are directed peripherally into the caudal germ wall, away from Rauber's sickle.

Thromboembolic events after aortic valve replacement in elderly patients with a Carpentier-Edwards Perimount pericardial bioprosthesis.

Objectives: Thromboembolic events after aortic valve replacement with a bioprosthesis were the most frequently occurring complications in elderly patients. Whether this was valve related or dependent on other factors needed further exploration.

Methods: Five hundred patients with a median age of 73 years were followed retrospectively after aortic valve replacement with a pericardial prosthesis for occurrence of thromboembolism.

Role of age, gender and association of CABG on long-term results after aortic valve replacement with a Carpentier-Edwards bioprosthesis in the elderly.

Aim: The problem of postoperative sudden death and the effect of age, gender and association of coronary artery bypass grafting were studied after implantation of a bioprosthetic valve in aortic position.

Design: retrospective investigation during 13 year.

Setting: general hospital.

Induction of the avian coelom with associated vitelline blood circulation by Rauber's sickle derived junctional endoblast and its fundamental role in heart formation.

In histological sections through chicken blastoderms of different ages we describe the temporospatial relationship between junctional endoblast, the formation of blood islands (appearing first from a peripherally migrating mesoblastic blastema), and the formation of coelomic vesicles developing later in/and from a more superficially extending mesoblastic blastema (coelomic mesoblast). After unilateral removal of the Rauber's sickle-derived junctional endoblast in early streak blastoderms (stage 2-4; Vakaet [1970] Arch Biol 81:387-426) and culture to stage 11 (Hamburger and Hamilton [1951] J Morphol 88:49-92), we observed that the early formation of the coelomic cavity was locally or totally disturbed in the operated area. Besides the simultaneous absence of blood islands, the coelomic vesicles did not form normally.

The noncircular shape of the radial head.

Purpose: The purpose of this study was to define the shape of the radial head by identifying the relationship between precisely defined axes of the radial head.

Methods: An anatomic study was done to define the shape of the radial head and specifically the relationship between the long and the short axis. Twenty-seven cadaveric upper extremities were used.

Avian sickle endoblast induces gastrulation or neurulation in the isolated area centralis or isolated anti-sickle region respectively.

By the quail-chicken chimera technique, we studied, in culture, the inducing effect of sickle endoblast (derived from Rauber's sickle by centripetal and cranial migration) on the isolated Rauber's sickle-free central part of the area centralis or on the isolated Rauber's sickle-free anti-sickle region from unincubated chicken blastoderms. Just as Rauber's sickle, the flat one-cell-thick sickle endoblast (Stage 2-3, Hamburger & Hamilton, 1951) induces a primitive streak (PS) and a neural plate in the area centralis. If a vitelline membrane is interposed between the sickle endoblast and the area centralis, then a small primitive streak is still induced, suggesting the effect of a diffusible factor on PS formation.

Competitive inhibition by Rauber's sickle of the primitive streak and/or (pre)neural plate inducing effects of sickle endoblast in avian blastoderms.

When in unincubated chicken blastoderms the Rauber's sickle is (sub)totally mechanically removed by selective scraping, the further evolution of the blastoderm in culture is often profoundly disturbed, going from only expansion of the upper layer and preneural plate formation to the development of a slowly growing miniature embryo. Our results suggest that the developmental potencies of the embryo are related to the presence or absence of Rauber's sickle material left after its removal. This can be checked after culture by the presence or nonpresence of junctional endoblast (derived from Rauber's sickle) and the concomitant induction of blood islands in the immediate neighborhood.

Positional information by Rauber's sickle and a new look at the mechanisms of primitive streak initiation in avian blastoderms.

The present experimental in vitro study suggests that a primitive streak (PS) in avian blastoderms is induced by diffusion of morphogenetic substances emanating from Rauber's sickle. Indeed, even without direct contact between a quail Rauber's sickle and the reacting upper layer (by interposition of a vitelline membrane), a PS can be induced in the isolated area centralis or antisickle region of unincubated chicken blastoderms. The so-formed PSs are localized below the vitelline membrane in the immediate neighborhood of the apposed Rauber's sickle material.