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The healing process of bone fractures can be monitored by a measurement of the osteosynthesis plate bending. For this purpose a wireless magnetostrictive bending sensor is proposed. A planar rectangular coil on top of a magnetostrictive Galfenol ( alloy) layer forms an electrical resonant circuit. The sensor is manufactured in thin film technology. Coil turns were electrodeposited by pattern plating. Sensors with overall dimensions of (13 2 0.5) mm were manufactured with varied turn numbers showing self-resonance frequencies from 5 to 50 MHz. Examined sensors possess linear frequency-force characteristic up to 6 N with frequency shifts of 6 kHz . In order to obtain the sensor resonance frequency wirelessly, several measurement techniques were employed using inductively coupled coils. Frequency domain measurements have been carried out by employing a network analyzer with a single detection coil and a lock-in amplifier with separate coils for excitation and detection. In time domain measurements, two coils for transmission and reception are used. In the transmit case a short sine pulse excites the sensor and afterwards its decaying response signal is received. To determine the resonance frequency, a frequency counting, Fourier or wavelet technique can be used. By integrating additional cores of high permeability into sensor and detection coil, measurement ranges can be increased. [ABSTRACT FROM PUBLISHER]

Microtechnology components are already pointing the way forwards in minimally invasive diagnosis, therapy and therapy monitoring, in implants and medication dosage systems. The latest developments show a wide range of new possible uses for microtechnology in medical applications. The world market in physical pressure, temperature and acceleration sensors was worth several hundred billion euros in 2003. Given the extreme miniaturisation now possible through micro- and nanotechnology, such sensors readily suggest themselves for medical applications. If physical sensors are linked to a telemetric unit for wireless data transmission, are biocompatibly packaged or are implanted in a minimally invasive procedure, then bodily functions such as the acceleration of vessel walls, blood pressure, temperature or nerve streams can be measured permanently and wirelessly. Regarding pressure sensors, surgical diagnosis is yielding a range of possibilities extending from pressure measurements in the brain following a trauma, compartment pressure measurements in the abdomen, organs or extremities through to bladder pressure measurements for injury patients with compartment syndrome. The present work gives a surgery-based overview of the latest developments and trends in this high technology field. [ABSTRACT FROM AUTHOR]

Introduction: Using a cadaver model and multiple continuous compartment pressure measurement, we sought to determine the pressure distribution in different osseofascial spaces of the foot and determine the quickest and most effective technique of pressure release., Materials and Methods: The compartment pressures were measured (in mmHg) in five different osseofascial spaces of each foot. In stepwise manner, warmed saline was injected only into the central compartment only. Three experimental approaches to fasciotomy were studied., Results: We recognized a simultaneous exponential increase of all foot compartments in all experimental models. With a medial fasciotomy technique first, a flexor brevis compartment incision was necessary to release pressures in the central compartments. Following this procedure, pressure was released in the tarsal tunnel and in the intermetatarsal area immediately. Pressure reduction in the central flexor space and in the tarsal tunnel was less effective with a dorsal fasciotomy technique., Conclusions: There is no pressure increase of a "single" osseofascial space in case of a foot compartment syndrome. If immediate pressure release is required, a medial fasciotomy technique including the central flexors should be favoured.

Technologies in telecommunication and information are being increasingly applied in the public health system of the western world. Also responsible for this development is the cost factor in the field of financing and maintenance of such a system of superior medical supply, as well as the concurrent patient' demand for optimized medical "24 h care and treatment". Pioneers in the use of telematic projects have, up until now, been large states such as the USA, Canada, Norway or Australia. Such projects have been used to provide, guarantee and maintain medical care in geographically remote regions with few medical facilities. After breaking the obstacle of geographic distance, telemedical solutions in general, and especially the tele-visit, represent a new form of treatment for patient care after discharge from hospital. In the year 2002, a prospective randomized two-armed study was initiated including patients after surgical intervention by arthroplasty in posttraumatic contracture of the elbow. The system of the tele-visit was used for 6 weeks after discharge and the patients were controlled as outpatients after 6 months, including a physical examination. The functional outcome, duration of stay in hospital and the costs for treatment arising were determined. A standardized questionnaire was developed and the degree of satisfaction of the patients surveyed. A shorter stay in hospital was found together with lowered costs in medical treatment, while no differences in functional outcome could be found in comparison to the control group, although there was an additionally high grade of satisfaction with the new system.

The televisite is a form of application of telemedicine, that allows a communication between the patient and the family doctor or specialist in the clinic after discharging of hospital. Pioneers for the use of telematic projects have been up to now wide states like the USA, Canada, Norway or Australia to provide, guarantee and maintain by the means of telemedical solutions medical care in geographic regions hardly reachable and of little medical attention. In central Europe and Germany telemedicine is gaining in significance on the one hand because of increasing importance of the cost factor and resulting pressure on the public health system and on the other hand because of the rising demand of the patients for optimised medical care. It specially represents a new form of treatment in patients care after dischargement of hospital. In the year of 2002 a prospective randomised two-armed study was initiated including patients after operative intervention by arthroplasty in posttraumatic contracture of the elbow. The system of the Televisite is used for 6 weeks after dischargement and patients had been controlled ambulant after 6 months including a physical examination. The functional outcome will be scored, the duration of stay in hospital measured, the arising costs for treatment calculated and the satisfaction of the patients in handling the Televisite surveyed. Over this first results showed a shortened stay in hospital together with lowered costs in medical treatment on the one hand and on the other no difference in functional outcome could be found in comparison to the control group by additionally high grade of satisfaction with the new system.

In cases of extended post-traumatic soft-tissue and bone loss as well as with mutilating infection or radical tumor resection, multidisciplinary options are required to salvage extremities and functional rehabilitation. A surgical team approach allows for reduction of amputation rates, wound healing complications, and secondary procedures in limb oncology and trauma. The goals and limitations of cooperative surgical concepts are described. In the future, continuing medical education will focus not only on indications and techniques but also on complication management, medicolegal problems, and economic deficits due to maladapted legal structures. Provided clear clinical pathways are introduced to guide indications, surgical procedures, and postoperative treatment, marked financial deficits may be avoided. While, in the past, responsibility for the patient and ethical considerations resulted in the development of voluntary interdisciplinary treatment programs, economic strategies and an increasing number of malpractice suits will inevitably produce new imperatives for interdisciplinary cooperation in the future.

The purpose of the present biomechanical investigation was to check the functional importance of the syndesmosis ligaments and of the deltoid ligament for ankle fracture type B according to the AO-Weber classification. We constructed a special fixation clamp, with 12 fresh and unembalmed lower legs being tested for lateral shift (mm) and ten for tibiotalar rotation. All specimens were exposed in the same neutral position. Transverse loads (F(y)) varied between 0 and 150 N, axial loads (F(z)) between 0, 300, 600 and 1,000 N and rotational loads (F(r)) between 2.4 and 4.9 Nm. All series were repeated according to supination-eversion (SE) injury patterns of the Lauge-Hansen classification. Syndesmotic ligaments and the fibula were incrementally sectioned from anterior to posterior. Type SE I consisted of an isolated incision of the anterior syndesmosis ligament. Type SE II had an additional oblique fracture of the fibula at the height of the tibiofibular syndesmosis. In type SE III injuries, in addition to the fibular fracture, a complete rupture of the syndesmosis ligaments was present, and for type SE IV lesions the deltoid ligaments were incised. The transverse load-displacement curve was s-shaped in all uninjured joints,with the highest gradient between 10 and 20 N with no axial compression. Without axial compression in cases of F(y)=25 N transverse loads, the mean talus translation was 0.51 mm. Following type II injuries, the average talus translation was 0.68 mm (not significant) and rose to an average of 0.95 mm ( P <0.01) in type III injuries. After additional incision of the deltoid ligaments, the ankle joint subluxed permanently when more than 5-10 N transverse loads were applied. Axial loads of 300 N or more resulted in a considerable reduction in talus translations, indicating increased stability and congruency within the joint complex. In this way, the vertical loading of the ankle joints always contributed to joint stability. The average internal tibiotalar rotation reached with a torque of 2.4 Nm was 3.52 degrees and with 4.9 Nm 5.15 degrees when no axial compression was applied. External rotation measured -6.36 degrees and -8.62 degrees, respectively. Following the experimental protocol, significant increases were noted for external rotation at SE II degrees injuries ( P =0.003) and for internal rotation at SE III degrees ( P =0.03) injuries. Our data support the proposition that the deltoid ligaments and the posterior syndesmosis play a key role in the stability of ankle fractures for supination-eversion injuries. If these structures remain intact, conservative and early functional treatment are recommended in patients with minimal (<2 mm) or no fracture displacement. This concept is confirmed by the literature dealing with clinical mid- and long-term follow-up studies.

The idea of Televisite is to equip the patients with a camera and a communication panel at the time of their discharge from the hospital. In that way patients and physicians are able to continue the treatment and the rehabilitation program. An easy to handle interface helps the patient to answer simple questions or to send voice recordings, pictures or videos via a service centre to the doctor in attendance. This concept has the great advantage that the patients has to visit the physician in the office or in the hospital only when absolute required. Routine checks can be done by telecommunication. Thus the efficiency of the system may significantly contribute to lower costs in the health care system.

The TELTRA Televisite is a remote patient monitoring system, allowing the patient to remain at home and deliver monitoring data, images, speech and video recordings to the doctor. From this point, all the above mentioned sources of information will be referred to as data. As a medium for the information transfer, the Televisite uses ISDN or multi-channel HSCSD telephone. The system software architecture consists of the design of graphics patient interface, gathering and processing of data, transmittal of data and most importantly, providing highest security at all stages of the data, between patient and database server. The system also provides facility for emergency telephony between the patient and the physician. The technology employed in the Televiste is based on store and forward, where data is first collected and sent to the doctor at the end of a teleround session.

The Televisite application is a post-stationary consulting method, whose main aim is to reduce the treatment time of inpatients. It provides a high quality home consultation after the patient has been discharged from the hospital. The technical handling and the validity of the new method of caring will be analysed--particularly the human-machine interface. In a prospective study case injured patients were attend using the Televisite. For communications with the consulting doctor they were supplied with a high resolution digital camera and a mobile PC with an integrated HCSCD cell phone. The doctor examined the data transmitted by the patient and remotely consulted the patient using the Televisite. Through a simple self-explaining user interface, a smooth information transfer was guaranteed.

Femoral neck fractures are frequent fractures of the elderly. They can be treated by the use of dynamic hip screws, lag screws, bipolar hemi-protheses or total hip replacement. The results are markedly influenced by the timing of the operation and the choice of the implant. Using the Garden classification of femoral neck fracture we demonstrate a different therapeutic approach according to Garden stadium I-IV.

Acute Achilles tendon ruptures are mostly related to recreational activities. Therefore, these patients intend to return to sports as soon as possible with no functional deficiency. This is the first study, comparing functional results after functional treatment to those after surgery. According to sonographic examinations of the tendon gap, primary functional treatment with heel supported shoes or surgery were suggested. Between 2/1991 and 12/1992, 22 patients with acute Achilles tendon rupture were treated without operation (group 1) and in 10 patient the rupture was sutured (group 2). 6 months later, 27 patients underwent standardized clinical examination: one leg standing for one minute, measurement of the circumference of the calf. The actual activities were assigned to Tegner Activity Score. 19 patients had isokinetic cybex testing with 60 degrees/s. There were 3 re-ruptures in group 1 and no comparable complications in group 2. At this time, clinical examination and Tegner Activity Score showed no relevant differences. Force of flexion was 30.4% lowered in group 1 and 2.4% in group 2. Additional training of the calf muscles improved the results after 6 weeks in group 1. We concluded that individual management of acute Achilles tendon rupture is possible according to sonographic tendon gap. Functional treatment is effective, but the rate of re-ruptures has to be reduced by careful selection of patients (rupture gap < or = 2 mm, high cooperation).

1. The perivascular nerves of isolated tail arteries from Wistar rats were stimulated with field pulses (1 Hz, 2 pulses, every 2 min). omega-Conotoxin 10 nmol l-1 depressed neurogenically mediated contractions, but did not influence the contractions to noradrenaline 0.1-0.3 mumol l-1. 2. The inhibitory effect of omega-conotoxin was concentration-dependent (IC50 = 3.8 nmol l-1). It did not reach a steady-state during 30 min incubation and could not be reversed upon subsequent washout for another 60 min. 3. A gradual increase in the Ca2+ concentration of the medium from 1.25 mmol l-1 to 10 mmol l-1 enhanced vasoconstriction and attenuated the action of omega-conotoxin 10 nmol l-1. When a low stimulation intensity (120 mA) was used at high external Ca2+ (10 mmol l-1), similar contractile responses were obtained as under normal conditions (200 mA current, 2.5 mmol l-1 Ca2+). However, the inverse relationship between the effect of the toxin and external Ca2+ remained unchanged. 4. The time-course and degree of the inhibition by omega-conotoxin 3 nmol l-1 was identical in tail arteries of spontaneously hypertensive rats (SHR) and their normotensive controls (WKY). 5. When tail arteries of Wistar rats were preincubated with [3H]-noradrenaline, field stimulation (0.4 Hz, 24 pulses, every 16 min) evoked tritium overflow and vasoconstriction. omega-Conotoxin 30 nmol l-1 inhibited both responses to a similar extent. 6. Our results suggest that omega-conotoxin selectively blocks Ca2+ channels in the terminals of perivascular nerves and thereby reduces the release, but not the contractile effect of the sympathetic transmitter.