[Does coxitis fugax predispose for later Perthes' disease?--first results of an insurance data-based study]. / Prädisponiert die Coxitis fugax für einen späteren Morbus Perthes?--Erste Ergebnisse einer auf Versicherungsdaten basierenden Untersuchung.

INTRODUCTION: For decades, it has been a matter of debate whether coxitis fugax (CF) may trigger the onset of Perthes' disease (PD). However, the low incidence of both conditions limits the validity of clinical studies. As a novel approach, an analysis of patient data provided by a private health insurance (PHI) was performed. After calculation of the frequencies of CF and PD possible correlations were statistically assessed. We hypothesised that CF predisposes to the development of PD. MATERIALS: A retrospective database analysis was conducted based on insurance data of patients aged between 1 and 14 years covering an observation period of 7 years. Cases of CF and PD were detected by a search algorithm based on the International Classification System of Diseases (ICD) encoding the ICD codes M12.85 to CF and M91.1 to PD, respectively. Cases where CF was followed by PD were separately assessed for plausibility considering the clinical course and the length of the symptom-free interval. Statistical analysis was performed by using the chi-square test with a significance level set at 5 %. RESULTS: Among a cohort of 407,875 children 960 cases of CF were detected. Of these, 876 (91.3 %) had one single event of CF whereas 84 (8.7 %) children had two or more episodes. The average incidence of CF was 0.24 % per year. The frequency of PD was calculated to be 15.7 cases per 100, 000 children per year. In eleven cases (all male) CF was found to be followed by PD, however, after checking for plausibility only three cases remained. Statistical analysis revealed that the incidence of PD in male children with a previous CF episode was 21-times higher compared to children without CF (p < 0.0001). DISCUSSION: The results of the hitherto largest study including more than 400 ,000 children showed a significantly higher rate of PD in male children with previous CF compared to boys without CF. However, different patterns of age distribution and the observation that multiple CF episodes do not trigger the development of PD contradict the assumption of a possible correlation between these two diseases. In two of the three cases where CF was followed by PD a so-called "late onset PD" was evident suggesting a misdiagnosed PD at initial presentation. The chosen study design using patient data provided by a PHI allows the acquisition and evaluation of large numbers of cases which may help to elucidate possible correlations between different medical conditions. To unambiguously answer the hypothesis of this study, the inclusion of additional insurance data is necessary.

[The spinoglenoid ligament - an anatomic study]. / Das spinoglenoidale Ligament - eine anatomische Studie.

PURPOSE: In over-head motion athletes a dysfunction of the suprascapular nerve has been described. In the literature a relation between the spinoglenoid ligament and the dysfunction of the suprascapular nerve is mentioned. An appreciable variability of this ligament is described. The purpose of the present study was the anatomic documentation of the spinoglenoid ligament and its relation to the suprascapular nerve. MATERIAL AND METHODS: In 36 shoulder specimen the suprascapular nerve, the spinoglenoid and bony parameter of the scapula were documented. The statistic evaluation was performed with SPSS12.0. RESULTS: In all but one specimen a spinoglenoid ligament was present. In 20 cases (56 %) the infraspinatus muscle inserted at the spinoglenoid ligament. In five cases (14 %) the spinoglenoid ligament reached the glenohumeral joint capsule. In two cases the suprascapular nerve was completely fixed with the ligament, in four cases the perineural soft tissue had a close connection to the ligament. In four cases a branch of the nerve passed through the ligament. All together in 28 % of the specimen there were mechanical conflicts. In one case a ganglion compressed the nerve. CLINICAL RELEVANCE: Our anatomic study showed in a significant number of cases a possible entrapment of different origins. These findings have implications both for diagnostics and treatment.

[Prospective, randomised study of the Bauer and ALMI approaches concerning MRI findings and muscle-specific blood parameters]. / Prospektive, randomisierte Studie zwischen Bauer- und ALMI-Zugang unter Berücksichtigung von MRI-Befunden und muskelspezifischen Blutparametern.

PURPOSE: The purpose of the present study was to evaluate the MRI of the hip musculature as well as specific blood parameters on comparison of the Bauer approach with the minimally invasive ALMI approach. MATERIAL AND METHODS: We compared two patient groups after total hip replacement, which were operated either via the Bauer or the ALMI approach. All 47 patients had the same cementless hip design. All surgeries were performed by two experienced hip surgeons with experience of more than 1200 ALMI approaches. The patient groups did not differ concerning age, sex or side which was operated on. All MRI were performed in a standardised technique with a Philips Outlook Proview (0.23 Tesla). Patients were scanned preoperatively, within 2 weeks after surgery and at time of follow-up 14 months after surgery. The evaluation of the MRI findings was performed by two independent and blinded examiners. In order to document the muscle damage we documented myoglobin (the day before surgery, 6 hours postoperatively and at the first postop. day) und troponin (6 hours postoperatively). RESULTS: Preoperatively the male patients showed a significantly larger diameter of the gluteus medius muscle. We also could demonstrate in many patients a fatty degeneration even before surgery. At time of follow-up there was no significant difference between the two patient populations concerning the fatty degeneration. There was also no significant difference concerning the muscle atrophy. Muscle oedema, that was present before surgery, however, was no longer present at the time of follow-up. Two patients even preoperatively showed a lesion of the gluteus medius tendon. The range of the postoperative myoglobin level was high (118-5411 µg/L), in the ALMI group the standard deviation was 1445 µg/L, in the Bauer group it was 738 µg/L. There was no significant difference between both groups. Similar findings were documented for the troponin levels. CONCLUSION AND CLINICAL RELEVANCE: Even before THR many patients show significant degeneration in the hip muscles. Muscle oedema that was present before surgery had disappeared at the time of follow-up. The fatty degeneration was still present at the time of follow-up. There was no difference concerning the muscle atrophy between the ALMI and the Bauer groups.

Suprascapular nerve block as a method of preemptive pain control in shoulder surgery.

The purpose of the study was to evaluate the effect of suprascapular nerve block (SSNB) in shoulder surgery. The study group consisted of 260 patients, which were subjected to shoulder operations. The patients were divided into two equal groups: group I with nerve block compared to a control group II without a nerve block. The mean age of the patients in group I was 56.2 +/- 6.86 years and that in group II was 54.5 +/- 7.06 years. The female to male ratio was 71:59 in group I and was 69:61 in group II. Surgical procedures were arthroscopic rotator cuff repair, arthroscopic subacromial decompression, arthroscopic acromioclavicular resection, arthroscopic removal of calcific tendonitis, arthroscopic reconstruction of instability, arthroscopic capsular release and shoulder replacement. In all cases the pain was documented by the visual analogue scale (VAS) preoperative, at the first, the second as well as at the third day after surgery. In order to evaluate the amount of fluid, which is needed for infiltration of the area of the supraspinatus fossa, we injected different amount of local anesthetic in combination with contrast dye in five patients. In this study to document the fluid distribution, after injecting with different milliliters, 10 ml is proved to be more than enough to have sufficient local anesthetic to block the SSN. Pre-operatively the mean VAS was comparable between both groups. We documented a significant difference in favour of SSNB from day 1 to day 3 after surgery. No specific complications due to this nerve block procedure were found in any patient post-operatively.

Perivascular axillary brachial plexus block and patient positioning: the influence of a lateral, head-down position.

The aim of this study was to examine the effect of a 20 degrees Trendelenburg position on the blockade of nerves that exit the brachial plexus proximally in patients undergoing single-injection axillary brachial plexus block. After a pilot study of eight cadavers suggested that a head-down and lateral position would encourage the proximal spread of local anaesthetic, 72 patients undergoing elective surgery were divided into two equal groups: a Supine group and a Modified Position group (lateral position, 20 degrees head-down tilt). Patients were left in the allocated position for 30 min after an axillary block had been performed with alkalinised mepivacaine 1% 49.5 ml. Sensory and motor blockade evaluation showed that there was a significantly higher proportion of axillary nerve (76% vs. 0%, p < 0.001), thoracodorsal nerve (86% vs. 0%, p < 0.001) and subscapular nerve (89% vs. 0%, p < 0.001) blockade in the Modified Position group. Sensory block of the radial nerve was also improved by the modified position (100% vs. 86%, p < 0.05).

[A solution to add digital signatures to medical images according to the DICOM standard: embedded systems]. / Ein Lösungsweg, um medizinische Bilder mit digitalen Signaturen nach dem DICOM-Standard zu versehen: Embedded Systems.

Radiology departments often underestimate the importance of protecting medical data during transmission, including the precautions taken to ensure data protection. In teleradiology, transmitted as well as stored patient data have to be signed digitally according to the currently valid regulation (Rontgenverordnung, RoV). The DICOM standard facilitates a digital signature. So far, medical image manufacturers only announced to support this security feature. We introduce a solution that extends the feature of digital signing to older modalities.

Neuronal regeneration after application of radiofrequency energy to collagenous tissue is affected by limb immobilization: an in vivo animal study.

Despite widespread use of radiofrequency (RF)-shrinkage, there have been no studies on the influence of RF-energy on neural elements of collagenous tissue. The purpose of this study was to examine the effect of RF-shrinkage on neural structures of capsuloligamentous tissue and the recovery of neural elements under different postoperative treatment protocols. One patellar tendon of 46 New-Zealand-White rabbits was shrunk. Six rabbits were sacrificed immediately postoperative. Twenty rabbits were not immobilized, 10 were immobilized for 3 and 10 were immobilized for 6 weeks. A monoclonal antibody, specific against a neurofilament protein, was used to detect nerves and neural structures. Staining pattern of nerve fibres was significantly altered immediately postoperative. After 3 weeks the number of nerve fibres and bundles decreased significantly in immobilized and non-immobilized limbs. The loss of nerve fibres was significantly less in immobilized limbs. At 6 weeks the number of neural elements in immobilized limbs increased to the level of untreated control tissue. In non-immobilized limbs we found no recovery of neural elements 9 weeks postoperatively. At this time the number of nerve fibres and bundles was still significantly less compared to the untreated control limbs. RF-shrinkage causes significant alteration of neural elements. Under immobilization nerve fibres and bundles reach the level of normal untreated tissue. Careful rehabilitation is important after RF-shrinkage. Not only for biomechanical reasons, but also to allow the neural elements to recover, thermally modified tissue should be protected from normal physiologic loads.

Patient data security in the DICOM standard.

The DICOM committee added the section "Security Profiles" to the DICOM standard, in order to provide the opportunity of safe communication between health care system partners. Data complying with the DICOM standard--e.g. pictures, signals or reports of examinations can be provided with one or more digital signatures. Attention should be paid to the fact that these possibilities of the DICOM standard are available or can be supplied subsequently by new acquisitions of radiological modalities. The required information to check these prerequisites are given.

[Does the digital signature of the DICOM standard meet the requirements of German law?]. / Entspricht die digitale Signatur des DICOM-Standards dem deutschen Signaturgesetz?

The DICOM standard offers the possibilities to generate electronic signatures, valid according to German laws. This enhances the reliability of the correlation between image and patient data. However, only so called qualified electronic signatures--conveniently issued by an accredited supplier--are permissible and not rejectable as evidence in German jurisdiction and are completely equivalent to the handwritten signatures. These qualified electronic signatures can be executed only by individuals, whereas the former are not applicable to technical apparatus like image generating modalities. In consequence, a modality is able to provide its pictures with a "common or advanced signature" solely. This limits the use of the digital signature of the DICOM standard for further applications, e.g. the verifiability within the teleradiology.

[Thiel method fixed cadaver ears. A new procedure for graduate and continuing education in middle ear surgery]. / Nach Thiel fixierte Leichenohren. Ein neues Verfahren für die Aus- und Weiterbildung in der Mittelohrchirurgie.

BACKGROUND AND OBJECTIVE: An efficient training program in ear surgery needs suitable models to learn the specific preparation techniques. However, conventionally fixed or fresh frozen ears of human corpses do not meet all demands. Therefore we investigated the feasibility of ears fixed according to Thiel for surgical training in the temporal bone lab. METHODS: Various surgical techniques on external and middle ears were evaluated on ears from cadavers fixed according to Thiel. Structure and consistency of the tissues were compared to vital conditions by means of a standardized questionnaire. RESULTS: Structure and consistency of the tissues of the auditory canal, the tympanic cavity and the mastoid were comparable to vital conditions. Merely the cartilage of the auricle was considerable softened. This enabled a surgical preparation under conditions close to the intravital situation. CONCLUSIONS: Under the aspects of quality assurance and efficiency of continuous medical education in middle ear surgery, the Thiel fixation technique provides an excellent prerequisite.

Interindividual reproducibility in perioperative rotational alignment of femoral components in knee prosthetic surgery using the transepicondylar axis.

Femoral component malalignment is one of the main causes of persisting anterior knee pain after knee replacement. This study examined interindividual reproducibility in perioperative definition of the transepicondylar axis (TEA) as a reference for measuring the rotational alignment of the femoral component. Eight surgeons experienced in knee prosthetic surgery marked on Thiel-embalmed cadaver specimens the reference points that they would normally use to define the TEA during knee replacement. These were digitized by a video system, and all the spots defined by the surgeon were translated into a reference picture, allowing a digital analysis of the distances between all the spots marked. The maximal distance between the spots that the participants had marked as relevant for the TEA was 13.8 mm at the lateral and 22.3 mm at the medial epicondyle. Projecting all spots marked into one picture resulted in an area of 116 mm2 on the lateral and 102 mm2 on the medial epicondyle. The median range of the fault between two different participants was 6.4 mm on the lateral side (range 13.2 mm) and 9.7 mm on the medial (range 21.6 mm). Because the rotational alignment of the femoral component is extremely relevant for successful implantation of total knee prosthesis, the interindividual discrepancy in defining the TEA as reference is rather high. As this reference line is commonly used, the perioperative variance and the resulting rotational discrepancy of the femoral component must be considered.

[Basic principles and surgical technique of tibio-fibula-plasty in cartilage-bone transplantation]. / Grundlagen und Operations-technik der T(ibio)-F(ibularen)-Plastik zur Knorpelknochen-transplantation.

BACKGROUND: Within the last few years autologous cartilage-bone-grafting is becoming an established standardized procedure in joint surgery. One significant disadvantage of this technique is the harvesting of the bone plugs from the weight-bearing area of the knee joint. PURPOSE: The tibiofibular articulation is located close to the knee joint that is operated on. This articulation is covered with cartilage. The purpose of this study was to evaluate the question, whether this joint is suitable as a donor site for bone-cartilage transplants. MATERIAL AND METHODS: Favourable approaches and committing of anatomical landmarks were investigated on 44 fixed tibiofibular joints. In knee extension, the shortest distance between the joint cleft and common fibular nerve was measured. The cartilage thickness and histology of both the fibular and tibial joint surface were documented. The developed surgical approach was evaluated in patients. RESULTS: Histological and immunohistochemical examination showed hyaline cartilage and type II collagen. The average cartilage thickness was 1.9 +/- 0.29 mm (minimum: 1.5 mm; maximum: 2.6 mm). The peroneal nerve showed an average distance to the tibiofibular joint of 24 mm (minimum: 12 mm; maximum: 30 mm). Different surgical procedures are possible and clinical relevant. CLINICAL RELEVANCE: The tibiofibular joint contains cartilage, which may be a reasonable donor site even for the elderly patient. Harvesting the graft from this area may avoid iatrogenic damaging of intraarticular weight bearing cartilage of the knee joint.

Which joint position puts the axillary nerve at lowest risk when performing arthroscopic capsular release in patients with adhesive capsulitis of the shoulder?

The success of arthroscopic capsular release of the glenohumeral joint depends on complete incision of the inferior capsule. This study determined the distance between capsule and the axillary nerve in different joint positions. In 14 human shoulder specimens the anterior joint capsule and axillary nerve were dissected, and the anterior joint capsule was incised between the 1 and 5 o'clock positions. The shortest distance between the insertion of the inferior capsule and the axillary nerve was measured at the glenoid and humeral insertions in abduction, adduction, internal, and external rotation. The axillary nerve is surrounded from soft connective tissue and is closer to the humeral than to the glenoidal attachment of the joint capsule. During abduction and external rotation the nerve stays in its position while the glenohumeral capsule tightens, which increases the distance between the two structures. This results in the following distances: to the glenoidal/humeral capsule insertion: in adduction and neutral rotation, 21.2+/-4.2/14.2+/-2.6 mm; in abduction and neutral rotation, 24.0+/-4.9/15.0+/-5.0 mm; in abduction and internal rotation, 21.1+/-6.6/14.6+/-3.7 mm; and in abduction and external rotation, 24.9+/-3.8/16.4+/-4.4 mm. Thus, when performing arthroscopic capsular release the incision of the glenohumeral joint capsule should be undertaken at the glenoidal insertion in the abducted and externally rotated shoulder.

Entrapment of the lingual nerve due to an ossified pterygospinous ligament.

During a routine dissection course at the University of Muenster (Germany) an unusual course of the lingual nerve was found with entrapment of the nerve between a widely ossified pterygospinous ligament and the medial pterygoid muscle. Furthermore, the nerve's mobility was restricted by a more distal anastomosis with the inferior alveolar nerve. Although incomplete or complete ossification of the pterygospinous ligament is not uncommon, the combination with a medial course of the lingual nerve has not been described before. Besides practical importance for surgeons and anesthetists, the entrapment of the lingual nerve may lead to lingual numbness and pain associated with speech impairment.

The posterior subdeltoid approach: a modified access to the posterior glenohumeral joint.

A modified surgical approach to the posterior aspect of the glenohumeral joint and/or the dorsal glenoid is described. This access does not alter any muscle insertion or neuromuscular planes. After the skin incision is made, the inferior border of the spinal part of the deltoid is identified and the deltoid muscle is mobilized and retracted, thus offering an excellent approach to the interval between the infraspinatus and teres minor muscles. This interval is split parallel to the muscle fibers. This surgical approach was first established in 10 cadaverous shoulders and then performed in 12 patients with posterior shoulder pathology. In the cadaver study, the closest distance to the axillary nerve with this approach was 22 mm. In all 12 cases, the surgical procedure could be performed without any problems.

Ex vivo evaluation of novel miniaturized laser-induced interstitial thermotherapy applicators for effective small-volume tissue ablation.

RATIONALE AND OBJECTIVES: For effective small-volume tissue ablation in clinical and experimental settings, smaller laser-induced interstitial thermotherapy (LITT) applicator designs are required. The aim of this study was to compare the ablation properties of recently developed ultrasmall and small to standard LITT applicators. METHODS: Laser-induced interstitial thermotherapy was performed on liver samples using ultrasmall, small, and standard LITT applicators. Thermotherapy was monitored by magnetic resonance imaging, and lesion sizes were measured for each image. True lesion sizes were then determined macroscopically and by histology. RESULTS: For continuous laser application over 5 minutes, maximum power settings were 5 W for the ultrasmall and small applicators and 10 W for the standard applicator. Given identical LITT settings, lesion volume measured by magnetic resonance imaging was significantly larger and histological tissue damage was more severe with the ultrasmall and small applicators than with the standard applicator. CONCLUSIONS: Small and ultrasmall LITT applicators can be used for effective tissue ablation of small target volumes in experimental and clinical applications.

[Surgical procedures in mouth, jaw and facial surgery in Thiel embalmed body donors]. / Operative Verfahren der Mund-, Kiefer- und Gesichtschirurgie an nach Thiel fixierten Körperspenden.

METHODS: This study investigates whether human cadavers embalmed according to Thiel can be used for research and education in oral-maxillo-facial surgery. Different surgical approaches were tested on such cadavers. The usability of the specimen was judged jointly by anatomists and surgeons. Color, structure, and consistency of the different tissues were comparable to vital conditions. Thiel's embalming technique applied to human cadavers provides an optimal basis for research and for basic and postgraduate medical education.

[Pathomorphology of laser-induced interstitial tumor thermotherapy of the liver]. / Pathomorphologie der Laser-induzierten interstitiellen Tumor-Thermotherapie an der Leber.

The aim of this study was to analyse pathomorphological findings after treatment with laser induced tumor thermotherapy (LITT) on liver tissue and to correlate the results with magnetic resonance imaging. LITT was performed ex vivo and in vivo using a Neodym-YAG-Laser. Lesions were monitored by MR-thermometry ex vivo and by contrast-enhanced MRI in vivo. After LITT the lesions were examined macroscopically, histologically, and electronmicroscopically. LITT-induced tissue damage was qualitatively evaluated, classified, and quantified by means of digital image analysis. Four different zones of tissue damage were identified within the lesions. Adjacent to the applicator the tissue was completely ablated while more peripheral lesions exhibited only sublethal cell damages seen by EM. In vivo the pattern of tissue injury followed the lobular architecture of the liver tissue. Ultrastructural examination revealed only in areas of minor tissue injury intact sinusoidal patterns. MRI overestimated the diameter of the core zone of complete tissue ablation both ex vivo and to a lesser extent in vivo.