Straight proximal humeral nailing: Risk of iatrogenic tendon injuries with respect to different entry points in anatomical specimens.

BACKGROUND: The purpose of the study was to evaluate the relationship of implant-related injuries to the adjacent anatomical structures in a newer generation straight proximal humeral nail (PHN) regarding different entry points. The proximity of the proximal lateral locking-screws of the MultiLoc proximal humeral nail (ML PHN) may cause iatrogenic tendon injuries to the lateral edge of the bicipital humeral groove (BG) as reference point for the tendon of the long head of biceps brachii (LBT) as well as the lateral insertion of the infraspinatus tendon (IST). MATERIALS AND METHODS: The study comprised n = 40 upper extremities. Nail application was performed through a deltoid approach and supraspinatus tendon (SSP) split with a ML PHN. All tests were performed in three different entry points. First nail (N1) - standard position in line with the humeral shaft axis; second nail (N2) - a more lateral entry point; third alternative (N3) - medial position, centre of the humeral head. After nail placement, each specimen was screened for potential implant-related injuries or worded differently hit rates (HR) to the BG and the IST. The distances to the anatomical structures were measured and statistically interpreted. RESULTS: The observed iatrogenic IST injury rate was 17.5% (n = 7/40) for N1, 5% (n = 2/40) for N2 and 62.5% (n = 25/40) for N3, which was statistically significantly higher (p < 0.001). Regarding the BG, the evaluated HR was 7.5% (n = 3/40) for both N1 and N2. Only the nail placed in the head centre (N3) showed an iatrogenic injury rate of 20% (n = 8/40) (p < 0.062). No statistically significant association between humeral head size and the HR could be observed (head diameter: IST: p = 0.323, BG: p = 0.621; head circumference: IST: p = 0.167; BG: p = 0.940). For the IST and BG, all distances in nail positions N1 and N2 as well as N2 and N3 differ statistically significant (p < 0.001). CONCLUSIONS: An entry point for nail placement in line or slightly laterally to the humeral shaft axis - but still at the cartilage - should be advocated.

Evaluation of Monaldi's approach with regard to needle decompression of the tension pneumothorax-A cadaver study.

BACKGROUND: Although needle decompression of tension pneumothorax through the second intercostal space in the midclavicular line (Monaldi's approach) is a life-saving procedure, severe complications have been reported after its implementation. We evaluated the procedure by comparing how it was performed on cadavers by study participants with different training levels. METHODS: Six participants including one thoracic surgeon performed bilateral thoracic drainage after Monaldi on 82 torsos. After the thoraces were opened, the distances from the internal thoracic artery (A), the site of the puncture (B) and the midclavicular line (C) were measured bilaterally with reference to the median of the sternum. Further, it was determined whether the participants had correctly identified the second intercostal space. The differences between B-A and C-B were analysed. RESULTS: The needle was placed in the second intercostal space in 136 hemithoraces (83%). The thoracic surgeon showed a hit rate of 0% laceration of adjacent vessels. All the other participants had hit rates between 10% and 15%. The interval B-A ranged from 2.88 to 5.06cm in right and from 3.00 to 5.00cm in left hemithoraces. The distance C-B lay between 1.03cm and 1.87cm (right side), and 0.84cm and 2.02cm (left side). CONCLUSION: In our collective, the main problem was failure to assess correctly the lateral extension of the clavicle. If this fact is emphasized during training, Monaldi's approach is a safe method for needle decompression of pneumothorax.

Carpal tunnel release: Safe and simple identification of the flexor retinaculum based on superficial anatomical landmarks.

The aim of our study was to project the borders of the flexor retinaculum (FR) onto superficial landmarks since its insufficient splitting is the most common reason for persistence of symptoms after carpal tunnel release. In 60 hands the radial and ulnar styloid processes were linked by a horizontal line and a longitudinal line was laid through the ring finger's radial side. These were intersected resulting in the reference point "A" on the forearm. As the second basing point "B", the radial margin of the ring finger at the palmar digital crease was chosen. Measurement of the FR was carried out with regard to the reference points. The proximal margin of the FR was located at 4% of the reference line A-B starting from point A and extended up to 52% of this total length. Results indicate that splitting alongside the proximal half of line A-B divides the FR completely. Clin. Anat. 30:512-516, 2017. © 2017 Wiley Periodicals, Inc.

Sensory nerve supply of the distal radio-ulnar joint with regard to wrist denervation.

The objective of this study was to determine the precise departure points of the articular branches innervating the distal radio-ulnar joint from the anterior and posterior interosseous nerves. The study sample consisted of 116 upper limbs from adult human cadavers. The articular branches were prepared under the dissection microscope to take measurements using the radial styloid process as point of reference. The articular branch departed from the anterior interosseous nerve at a mean distance of 2.9 cm proximal to the styloid for a radius length of 20.5 cm, and 3.7 cm for a radius length of 26.5 cm, respectively. For the posterior interosseous nerve, the departure point was at a mean distance of 3.1 cm (radius length of 20.5 cm) and at 4.0 cm (radius length of 26.5 cm). Apart from a single branch from the posterior interosseous nerve, all articular branches were located distal to the proximal border of the pronator quadratus. Results indicate that wrist denervation from the volar approach, if performed at the proximal border of the pronator quadratus, or from the dorsal approach at a distance of 4.8 cm (for a radius length of 20.5 cm) or 6.2 cm (for a radius length of 26.5 cm) proximal to the radial styloid process, will eliminate the nerve supply to the distal radio-ulnar joint in the majority of cases.

Minimally invasive approach to the radial nerve--A new technique.

PURPOSE: To describe a minimally invasive approach to find the radial nerve (RN) simply and safely by tracing the posterior antebrachial cutaneous nerve (PACN) without damaging muscles, using only the surgeon's hand to define a window for the skin incision. BACKGROUND: Although it is absolutely necessary to locate the radial nerve during osteosynthesis of the humerus, the literature lacks guidelines on how to do so. METHODS: We have dissected the upper extremities of 54 adult human cadavers, embalmed using Thiel's method. After the PACN was identified in a defined space, its course was traced proximally by incising the lateral intermuscular septum (LIS) of the upper arm and thereby reaching the radial nerve (RN). Subsequently, using the lateral epicondyle (LE) of the humerus as a reference point, the distances to the points where the PACN perforated the LIS, and where the RN was identified, were measured. These individual data were related to the total length of the humerus. RESULTS: The results indicate that with this approach and without harming musculature, the RN can be reached by tracing the PACN at a height of 11.1-13.0 cm (females) and 11.9-14.0 cm (males) starting from the LE. CONCLUSION: Our examination shows the PACN to be a convenient guide to the RN.

A transthyroidal method for arytenoid adduction: a basic anatomical study.

INTRODUCTION: Arytenoid adduction is a very effective procedure for medializing the posterior part of the vocal fold in vocal fold paralysis. Major drawback of the method is the technically sometimes-difficult access to the arytenoid with increased postoperative morbidity. Aim of this study was to provide basic anatomical data regarding the accessibility of the arytenoid cartilage through a thyroplasty window. Furthermore, to investigate the feasibility of an arytenoid adduction by fixation of a surgical screw to the arytenoid cartilage by using this approach. MATERIALS AND METHODS: 10 cadaver larynges, six female and four male, were dissected and measured for our points of interest. A standard manufacture-made surgical screw attached to a suture was anchored to the fovea oblonga of the arytenoid cartilage. RESULTS: Our anatomical measurements proved a mean distance from the posterior edge of the thyroid window to the arytenoid of about 8-9 mm in male larynges and 7-8 mm in female larynges. The distances did not differ significantly between the sexes. Pulling the anchored surgical screw medializes the posterior part of the vocal fold. DISCUSSION: Our data showed that there is a very constant morphometric relation between the thyroplasty window and the arytenoid cartilage. It is known that gender-related differences result in a veritable laryngeal dimorphism in nearly all absolute laryngeal dimensions. These differences appear to a much lesser extend in the distances from the surface to the depth, as was confirmed in our series. Using these findings led us to identification of the fovea oblonga near the muscular process as the most favorable point for fixation of a surgical screw through a conventional thyroplasty window. Pulling the attached suture medializes the arytenoid cartilage.

Accessory joints between basiocciput and atlas/axis in the median plane.

To explore the many osseous irregularities that are found in the area between the basiocciput, the anterior arch of the atlas and the tip of the dens axis we studied 99 cadaver specimens using magnetic resonance tomography (MRT), computed tomography (CT), median saw-cut sections, and histological sections. Additionally, "dry" specimens of the skull (n = 110), atlas (n = 56), and axis (n = 33) were investigated. In the median plane, the dry and cadaver specimens exhibited osteoarthritis-related osseous outgrowths and osteophytes of the articular surfaces of the median atlanto-axial joint (n = 63), and the presence of congenitally developed free ossicles (n = 22) and of third occipital condyles (n = 3). The largest osteophytes (giant osteophytes) (n = 4) of the anterior arch of the atlas formed osseous contact zones with the basiocciput that were visible histologically as real joints and were designated accessory median atlanto-occipital joints. The third occipital condyles also formed osseous contact zones, visible histologically as real joints, with the anterior arch of the atlas or with the tip of the dens, and were designated accessory atlanto-occipital or occipito-odontoid joints. Frequent free ossicles, incorporated into the accessory joint, were found by histological examination to be covered with hyaline cartilage.

The anatomy of the joint as a risk factor for Lisfranc dislocation and fracture-dislocation. An anatomical and radiological case control study.

he anatomy of the mortise of the Lisfranc joint between the medial and lateral cuneiforms was studied in detail, with particular reference to features which may predispose to injury. In 33 consecutive patients with Lisfranc injuries we measured, from conventional radiographs, the medial depth of the mortise (A), the lateral depth (B) and the length of the second metatarsal (C). MRI was used to confirm the diagnosis. We calculated the mean depth of the mortise (A+B)/2, and the variables of the lever arm as follows: C/A, C/B and C/mean depth. The data were compared with those obtained in 84 cadaver feet with no previous injury of the Lisfranc joint complex. Statistical analysis used Student's two-sample t-test at the 5% error level and forward stepwise logistic regression. The mean medial depth of the mortise was found to be significantly less in patients with Lisfranc injuries than in the control group. Stepwise logistic regression identified only this depth as a significant risk factor for Lisfranc injuries. The odds of being in the injury group is 0.52 (approximately half) that of being a control if the medial depth of the mortise is increased by 1 mm, after adjusting for the other variables in the model. Our findings show that the mortise in patients with injuries to the Lisfranc joint is shallower than in the control group and the shallower it is the greater is the risk of injury.

[Ultrasonographic imaging of pneumarthrosis of the knee joint--case report and experimental cadaver study]. / Sonographischer Nachweis von Luft im Kniegelenk - eine experimentelle Studie und klinischer Fallbericht.

In case of penetrating injuries near to the knee joint showing only a small skin lesion and no damage to tendons and neuro-vascular structures, opening of the joint cavity has to be taken into consideration. Besides surgical revision of the penetration canal, radiological depiction of free intraarticular air may be useful. We report the cases of two patients, who suffered from intraarticular effusion and pain two, respectively three days after a penetrating injury. In both of them, free intraarticular air in the suprapatellar region could be depicted by ultrasonographic assessment. Subsequent evaluation of radiographs showed intraarticular air already being there at the day of admittance. Performing an experimental study in fifteen cadaver knee joint specimens, the reliability of this technique was evaluated and documented. Using an injection needle, air was insufflated into the knee joints with or without previous instillation of fluid. Afterwards sonographic assessment was performed using 7,5 - 13 MHz linear probes and Siemens (Elegra) equipment. Ultrasonographic detection of pneumarthrosis of the knee joint was possible early and reliably in both of the patients reported. With sufficient experience of the clinician and adequate equipment, even singular intraarticular air blisters are detectable, especially in cases of concomitant intraarticular effusion. By ultrasound it was possible to detect pneumarthrosis with at least 0,5 ml, by X-ray with at least 2 ml. Ultrasonography proved to be a reliable diagnostic tool for the detection of free intraarticular air within the knee joint. This fact should be considered in the differential diagnosis of unclear knee joint disorders after penetrating injuries.

Sonographic evaluation of the thenar compartment musculature.

The thenar region was studied with ultrasonography in 10 healthy volunteers. All thenar muscles could be identified and their course followed entirely. In addition, their function could be assessed by scanning during unresisted or resisted active movements. Standard approach, normal appearance, and dynamic tests for each muscle are described.

[Ultrasound anatomy of the sciatic nerve of the thigh]. / Die Sonoanatomie des Nervus ischiadicus am Oberschenkel.

Ultrasound examinations of the sciatic nerve were performed using high-resolution transducers (7.5, 10 to 20 MHz) both in anatomical specimens and in healthy volunteers. The ultrasonographic anatomy (sono-anatomy) of the nerve, its course along the thigh and its echogenicity in comparison with muscles, tendons and adipose tissue were investigated in 10 isolated muscle/nerve preparations. In addition, the influence of the angle of the applied transducer on the various different tissues was evaluated. In the clinical part of the study, the sciatic nerve was identified ultrasonographically in both thighs of 50 sex-matched healthy volunteers aged between 2 and 76 years. The normal sciatic nerve presents as a tubular echogenic structure with parallel linear internal echoes in the longitudinal section, and as a punctiform moderately echoic structure in cross-section, with the perineurium producing bright boundary echoes. Varying the insonating angle of the transducer reduced echogenicity, but to a smaller degree than in muscles and tendons. Unequivocal identified of the sciatic nerve from the level of the gluteal fold to its bifurcation in the distal thigh was possible in all but one case. We conclude that the course of the sciatic nerve along the thigh can be reliably identified and imaged with high-resolution ultrasound.

Musculo-tendinous junction of the flexor carpi ulnaris muscle. An anatomical study.

The aim of the study was to evaluate the occurrence of the anatomical variations of the musculotendinous junction of the flexor carpi ulnaris (FCU) muscle and the variations of its insertion onto the pisiform. One hundred cadaver specimens preserved according to Thiel's method were assessed. Following careful dissection, the distance between the musculotendinous junction and the pisiform and the width of the muscle belly were determined. Three typical anatomical variations were found: 1) a large muscle belly running distally almost to the insertion onto the pisiform; 2) the muscle belly ending more proximally, with some large fibres running parallel to the tendon and almost reaching the pisiform; 3) the musculotendinous junction ending more proximally, with only single fibres continuing distally. The length of the tendon was greater than 10 mm. A number of variations of the distal region of FCU were observed. The presence of muscle fibres almost reaching the insertion point onto the pisiform have to be considered when interpreting MRI or ultrasound findings of this region.

Anatomical and safety considerations in establishing portals used for wrist arthroscopy.

Eight portals are used for wrist arthroscopy, five for the radiocarpal joint and three for the midcarpal space. These portals pass between important vessels and cutaneous nerves and the extensor tendons underlying the extensor retinaculum and permit access to the common pathologies of the wrist joints. The portals can be safely established making precise use of the external landmarks and are associated with little soft tissue damage and few complications when performed gently and through the dorsal side of the wrist.

[The lower trapezius muscle island flap. Anatomic principles and clinical relevance]. / Der untere M. trapezius-Insellappen. Anatomische Grundlagen und klinische Relevanz.

Up to now, there is no uniform anatomic description neither of the branches of the subclavian artery nor of the pedicle of the lower myocutaneous trapezius flap. A dissection study was carried out on 140 necks in 70 cadavers. Variations of the subclavian artery and its branches, vessel diameter at different levels, the course of the pedicle under the levator scapulae muscle, the arc of rotation of the island flap, and the variations of the segmental intercostal branches to the lower part of the trapezius muscle were examined. Results of this study enable us to suggest a new nomenclature for the branches of the subclavian artery, a proper pedicle definition, and a technique for safe flap elevation. The lower trapezius island flap is a thin and pliable myocutaneous flap with a constant pedicle which ensures safe flap elevation. This flap has the potential for a wider acceptance due to minor donor site morbidity, large arc of rotation, and an ample range of clinical applications in the head and neck area as an island flap as well as a free flap.

The Graz learning and training model for arthroscopic surgery.

Up to 30% of all operative procedures in orthopaedic surgery are performed arthroscopically. Because of the steadily increasing number of residents, it seems to be difficult both to maintain high standards and to guarantee an adequate training in arthroscopic surgery. However, in contrast to many other surgical techniques it is possible to learn and practice arthroscopy using artificial models and cadaver joints, provided that experienced surgeons and anatomists act as supervisors and instructors. The aim of this paper is to assess practice models and training programs which should guarantee sufficient practical experience during the training period.

[Colliculus atlantis--a rarely observed anatomic structure--in a transoral roentgen image of the thoracic spine]. / Der Colliculus atlantis--eine wenig beachtete anatomische Struktur--im transoralen Röntgenbild der Halswirbelsäule.

PURPOSE: To study the time and mode of the development of the colliculus atlantis, the rate of its occurrence, the causes for its absence, and the radiological-clinical importance in the analysis of open-mouth-view radiographs. MATERIAL AND METHODS: Retrospective analysis of standardized radiographs of the cervical spine in more than 20,000 adults and 100 children. Study of 234 human skeletons of different ages and of 38 isolated adult atlases. Cadaveric dissection of 42 adults (age 48-87). Axial radiographs of isolated atlases and analysis of the bony structures of the colliculus atlantis. RESULTS: The colliculus atlantis develops between age 10 and 13 years. It is always present after age 13 years. For the development of the colliculus atlantis a normal function of the craniocervical joints is necessary. In congenital dysmorphias of the craniocervical region with dysfunction of the craniocervical joints and in fractures of the dens axis before age 10 years with instable healing the colliculus atlantis is absent. CONCLUSIONS: The colliculus atlantis is developed at age 13 years apart from some rare exceptions as mentioned. Changes of the site and the structure of the colliculus atlantis allow an early diagnosis of certain traumatically and inflammatory diseases of this region. Furthermore, it serves as an additional parameter in functional analysis of the craniocervical joints.

Sonographic evaluation of focal nodular hyperplasias (FNH) of the liver with a transpulmonary galactose-based contrast agent (Levovist).

Focal nodular hyperplasias (FNH) are hypervascular, benign focal liver lesions. Differentiation of FNH from other focal liver lesions is of clinical importance. The purpose of this study was to examine the impact of a new, transpulmonary echo-enhancing agent SHU 508A (Levovist) and recent Doppler techniques in the sonographic evaluation of FNH. 43 patients with 61 focal nodular hyperplasias of the liver were examined with grey scale ultrasound and power Doppler ultrasound. Levovist, a galactose-air-microbubble suspension was administered intravenously in all patients, either by bolus injection (400 mg ml-1) or continuous pump-infusion (300 mg ml-1). Visualization of the feeding vessels and vascularity of the lesions were evaluated. The resistance indexes (RI) in the feeding vessel and the hepatic artery were assessed and compared with the diameters of the FNH. The mean diameter of FNH was 4.3 cm (+/- 1.0). Echo enhanced power Doppler ultrasound was superior to unenhanced power Doppler ultrasound in the detection of the feeding artery (85% vs. 98%) in FNH and depicted the internal vascular architecture more clearly, especially in lesions located in the left lobe of the liver. Lesions smaller than 3 cm did not show a characteristic vascular architecture with echo enhanced Doppler ultrasound. The resistance index of the feeding artery (mean: 0.51 +/- 0.08) is significantly (p < 0.0001) lower than that of the hepatic artery (mean 0.65 +/- 0.06) with a mean difference of -0.14 +/- 0.01 in the same patient. The RI of the feeding artery significantly decreased as the size of the FNH increased, whereas RI differences between the hepatic artery and the feeding artery increased with lesion size. Intravenous (i.v.) bolus injection of the contrast agent will depict the hypervascular nature of FNH more clearly than i.v. infusion, although the latter will significantly prolong the diagnostic window. In conclusion, i.v. infusion of Levovist improves the visualization of the feeding artery and the radiating vascular architecture in FNH located in the left lobe of the liver due to improved signal-to-noise ratio and results in more effective suppression of motion artefacts. Although echo enhanced Doppler ultrasound improves the detection of the low resistance arterial feeding vessel in small FNH, it will not, however, reveal a specific vascular pattern in these lesions.

Plastination in the neurosciences. Keynote lecture.

Plastination is a unique technique of tissue preservation developed by Dr. Gunther von Hagens in Heidelberg, Germany, in 1978. In this process, water and lipids in biological tissues are replaced by curable polymers which are subsequently hardened, resulting in dry, odorless and durable specimens. In neuroanatomy silicone and polyester resins are used. Silicone rubber is used for whole brains and brain dissections resulting in natural looking specimens. Polyester resin is used for brain slices resulting in an excellent distinction between gray and white matter. The silicone S 10 standard technique and the polyester P 35 technique are described in detail. The advantages of plastinated specimens in neuroanatomy teaching and research are discussed.