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Objectives: The influence of local pressure elevation on the adjacent compartment of the lower limb is poorly described. We examined these effects in a non-fractured cadaver model. Methods: Paired legs of unfrozen specimens were used. The pressure in the anterior and in the peroneal compartment of the contralateral limb was raised by bolus injections of saline (5cc bolus/60 seconds. Pressure changes in the adjacent compartments were measured. Results: Pressure increase in the anterior and peroneal compartment, up to 100 mmHg did not affect the mean maximum pressure changes in the other compartments. Exceeding 100 mmHg in the anterior compartment, the peroneal pressure was 13.67 mmHg(range 8-20 mmHg), the deep posterior 7.50 mmHg(5-13 mmHg) and the superficial compartment pressure was 6.67 mmHg(4-9 mmHg). In cases of raised pressures in the peroneal compartment above 100 mmHg, the anterior, deep and superficial posterior compartments showed pressures of 12.5 mmHg(11-15 mmHg), 7.5 mmHg(4-11 mmHg), and 7.5 mmHg(4-12 mmHg). Conclusions: Our data suggest that increased pressures in the anterior tibial or peroneal compartments do not directly influence the neighbouring compartments. It appears that in an intact compartment, the fascia seals pressure elevations in the range that is clinically relevant. Whether or not this may have clinical impact on the indications for single versus multiple compartment fasciotomy should be subject to further studies. [ABSTRACT FROM AUTHOR]

Abstract: We assessed the morphological characteristics and dimensions of the ilium and fibula to evaluate the suitability of particular areas of bone for use as donor sites for dental reconstructions that carry implants. We measured the dimensions of 130 bilaterally harvested ilium and fibula bones from 65 adult cadavers using osteometric methods, and analysed the effects of age, sex, and side. Dimensions at measuring points, overall suitability for implantation, and relations among age, sex, and side, were evaluated statistically. We report observations of bone morphology involving cross-sections, and clinical relevance. Although the mean dimensions of the fibula and iliac crest were adequate, some segments would not support an implant 10mm long and 3.5mm wide. The overall suitability of parts of the iliac block fell to 30%. Fibular morphology is characterised by constant height and width, and relation of cortical and cancellous bone. Bony dimensions on the iliac fossa and fibula were significantly greater in men than in women. Age had a negative impact in one area of the iliac fossa, but nowhere on the iliac crest. Side was not significant. We found differences in dimensions and morphology between measuring points on the same bone. Precise knowledge about which areas of the donor sites can reliably provide sufficient bone to carry implants after reconstructions will allow greater flexibility and safety when reconstructions are designed. [Copyright &y& Elsevier]

Background: Complex proximal humeral fracture ranks among the most common fracture types, especially in elderly patients. In locked plate fixation of proximal humerus fractures, the calcar is deciding for screws providing further medial column support. To date, the biomechanical effect of the length of these calcar screws is not well known. The purpose of this study was to analyze the effect of long calcar screws on fresh frozen prefractured cadaveric specimens. Methods: In the present biomechanical study, 8 pairs of cadaveric proximal humeri were fractured identically using a custom-made fracture simulator. ORIF was performed using a locking plate (PHILOS; Fa. Synthes). The specimens were tested in a biomechanical setup under increased axial load without any calcar screws installed, with short calcar screws and long calcar screws installed. Strain gages (4-wire-120 Ohm, Fa. Vishay) mounted on the locking plate were used to evaluate the fixation strain and to give an estimate for primary stability.. Results: The measured strain of the locking plate without calcar screws (804,64 µm/m) at maximum load (200 N) was significantly higher than with short (619,07 µm/m; p = 0.02) or long calcar screws (527,31 µm/m; p = 0.007). Additionally, strain with short calcar screws was noticeably higher in comparison to long calcar screws (619,07 µm/m vs. 527,31 µm/m; p = 0.03). Conclusion: Use of calcar screws improves the stability of realistically impacted 3-part varus humeral fractures. Long calcar screws that are positioned as close as possible to the joint provide further primary stability compared to short calcar screws. Level of evidence: Basic science study. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the visualizability, topography, and course of the mandibular canal with particular attention to the incisive canal on 3-T MRI. Particular attention was paid to the incisive canal anastomosis at the symphysis. A total of 64 dentate patients were examined using a modified T2 space sequence using 3-T MRI. The scans were analyzed with respect to the topography of the entire course of the mandibular canal, mental canal, incisive canal, and nutrient canals. The high-field MRI of the lower jaw allowed detailed visualization of the mandibular canal, the incisive canal, and the surrounding connective tissue structures. In the context of the present study, 3-T MRI was found to be a potentially useful imaging method for displaying the course of the entire inferior dental canal for pre-implantation planning, surgical planning, and diagnosis. [ABSTRACT FROM AUTHOR]

Background: The authors hypothesized that by modifying the sequence of the rhinoplasty procedure they could avoid comminuted fractures resulting in suboptimal cosmetic results. Methods: Percutaneous perforated lateral nasal osteotomies were performed in 36 fresh human cadaver heads. In the first group of 19 cadaver heads with big nasal humps, the perforations of the lateral wall were done before and digital infracturing after hump removal in 10 cases (subgroup A1). In the remaining 9 noses with big humps, the perforations and digital infracturing were performed after hump removal (subgroup group A2). In a second group of 17 cadaver heads with small humps, perforations were performed before hump removal in 8 cases (subgroup B1), and in the remaining 9 cases, the lateral walls were perforated after hump removal (subgroup B2). The number of fractured nasal bones was counted. In addition, the size and shape of the nasal bone fragments were described in a blinded fashion. Results: Analysis of the number of fractured nasal bones yields higher rates for 'osteotomies after' (8.44 vs. 5.83) and hump size 'big' (8.37 vs. 5.76), with some influence of age and gender. Conclusions: The pattern of fractures after perforations of the lateral wall seems to be more regular if the perforations are done before the removal of bigger humps. In noses with small humps or no hump, no difference is seen regarding the sequence of the perforations in relation to hump removal. [ABSTRACT FROM AUTHOR]

Purpose: Separation of midline abdominal wall components or other procedures involving the papilla umbilicalis within the context of abdominal wall reconstruction can significantly affect vasculature of the umbilicus. Adjusting dissection to the vascular anatomy of that region may evade such complications. For this purpose, an anatomic microdissection study was performed, focusing on the vascular architecture of the papilla umbilicalis in the midst of the stratigraphical anatomy of the midline abdominal wall. Methods: Ramifications of the epigastric vessels were filled with dye on 27 abdominal walls originating from 15 female and 12 male corpses. Vascular architecture of the midline abdominal wall was examined by X-ray imaging and microdissection focusing region of the papilla umbilicalis. Results: Vasculature of the papilla umbilicalis is provided by both myocutaneous and septocutaneous perforator vessels originating from the medial branch of the arteria epigastrica inferior and accompanying veins. On their way to the inferiolateral basis of the papilla umbilicalis, these perforators prove an intimate and regular association with the rectus abdominis muscle, and different components of the rectus sheath. Conclusions: Vasculature of the papilla umbilicalis is susceptible to damage resulting from separation of midline abdominal wall components or periumbilical dissections. To secure vasculature of the papilla umbilicalis, the integrity of the loose areolar fascia covering the posterior surface of the rectus abdominis muscle must be kept from being harmed by dissection. In addition, the musculo-fibrous-aponeurotic anatomy on either the left or the right side of the papilla umbilicalis must be left in structural continuity. [ABSTRACT FROM AUTHOR]

Epidemiology and risk factors of haemorrhoidal disease are not well defined. This study tried to evaluate if the appearance of haemorrhoids is related to a disturbed remodelling of the soft tissue of rectal mucosa and submucosa. Therefore, immunohistochemical expression profiles of five parameters as potential mediators in neoangiogenesis ( EGFR), in inflammatory cell activity ( COX-2), and in cell migration, differentiation, and wound healing ( notch-3, c-myc, and ß-Catenin) were analysed (Saed et al., Fertil Steril 83(Suppl 1):1216–1219, ; Saed et al., Fertil Steril 79:1404–1408, ; Stojadinovic et al., Am J Pathol 167:59–69, ). Haemorrhoidal tissue specimens were collected from 44 patients. Healthy rectal mucosa was obtained from 16 non-fixed fresh cadavers and served as control. Histological and immunohistochemical markers like EGFR, COX-2, notch-3, c-myc, and ß-Catenin were analysed semi-quantitatively, separately for mucosal and submucosal layer. Significantly increased expressions were found for EGFR, COX-2, and notch-3 in the mucosal and submucosal layer of haemorrhoidal tissue in comparison to normal rectal tissue. This finding confirms that haemorrhoidal disease may be regarded as a manifestation of a soft tissue disease. [ABSTRACT FROM AUTHOR]

Objective: To develop strategies that may assist the surgeon to prevent and manage severe bleeding complications after adenoidectomy and tonsillectomy. Study Design: Retrospective. Subjects and Methods: Expert reports for malpractice lawsuits or professional boards were reviewed. The review was restricted to “deaths” and “permanent generalized neurological deficiencies.” Results: Forty-three cases matched our search criteria, including 32 deaths. Adenoidectomy cases (2) were associated with immediate bleeding because of direct vascular injury resulting in one death. Tonsillectomy cases were associated with delayed and repeated episodes of bleeding resulting in 31 deaths, including 19 children. Autopsy verified predominantly aspiration and vascular injuries. An apallic syndrome prevailed in surviving patients. Conclusion: Careful inspection of the nasopharynx immediately before adenoidectomy and curettage in a piecemeal fashion under visual control is helpful to prevent direct injury to aberrant arteries. Tonsillectomy cases are associated with delayed and episodic bleeding with spontaneous cessation and young age. Inpatient observation should be strongly considered in cases with repeated bleeding episodes to provide immediate treatment. The follow-up should be focused on disturbed wound healing. Outcome appears to be dependant on adequate airway management. Rigid instruments and tracheotomy in case of intubation failure are highly recommended to facilitate airway protection and ventilation. [Copyright &y& Elsevier]

The purpose of this study was to compare the ability of T2-weighted three-dimensional turbo spin-echo (TSE) images, maximum intensity projections and three-dimensional volume-rendered images for delineation of semicircular canal dehiscence. In 26 patients with dehiscence of the superior and/or posterior semicircular canal and 26 control patients, TSE images were obtained with two different resolutions and maximum intensity projection (MIP) and 3D volume-rendered images reconstructed. All images were evaluated by two radiologists in consensus regarding the visualization of anatomical structures and dehiscence of the semicircular canals. Computed tomography was used to confirm or exclude dehiscence. Dehiscence of the semicircular canals was delineated on axial MR images and on 3D volume-rendered images, but not on MIP images. The number of false positive cases was reduced from 3 to 0 with an increase in matrix, rendering results similar to those obtained with CT. Dehiscence of the semicircular canals can be assessed on high resolution MR images. Volume-rendered 3D images allow for immediate perception of the location of defects in semicircular canal dehiscence. These images may facilitate understanding of the extent and location of the defects. [ABSTRACT FROM AUTHOR]

The purpose of the study was to obtain reference values for the sizes of anatomical structures of the inner ear on computed tomography (CT) images and to compare these values with those obtained from patients with Menière's disease. CT images of the temporal bone of 67 patients without inner ear pathology and 53 patients with Menière's disease have been evaluated. CT was performed in the sequential mode (1-mm slice thickness, 120 kV, 125 mA). Anatomical structures, such as the length and the width of the cochlea and of the vestibule, the height of the basal turn, the length and the width of the cochlear, the vestibular and the singular aqueduct and the internal auditory meatus and the diameter of the semicircular canals, were measured, using a dedicated postprocessing workstation. Reference values from the control group could be obtained. In the patients with Menière's disease, the length and the width of the vestibular aqueduct were smaller, compared with the values from the control group. The values obtained from the control group can serve as reference values for adult patients. The different sizes of anatomical structures of the control group and of patients suffering from Menière's disease suggest that functional impairment might be related to subtle morphological changes. [ABSTRACT FROM AUTHOR]

This survey investigates fallopian canal dehiscences in order to assess the risk of encountering an unprotected facial nerve during routine ear surgery. In a prospective non-randomized study, the intraoperative appearance of the facial canal in 357 routine ear operations was compared with 300 temporal bone specimens from 150 autopsies. Intraoperatively, a dehiscence was detected in 6.4% (23/357) of the operations, most frequently at the oval niche region (16/23 cases). The incidence increased with the number of operations (P<0.0002). Cholesteatoma surgery had the highest relative risk (RR 4.6) of exposing an unprotected facial nerve. Postoperatively, no persistent facial paralysis was observed. In four of five cases with a transient facial palsy due to local anesthetics, a bony dehiscence could be found. The anatomical study revealed fallopian canal dehiscences in 29.3% (44/150) of the autopsies. One-third (15/44) of the individuals affected displayed bilateral findings, thus resulting in 19.7% (59/300) of temporal bones affected. A total of 17/59 bones showed microdehiscences, and most (55/59) were located at the oval niche. The actual prevalence of fallopian canal dehiscences is significantly higher than intraoperative findings suggest. The oval niche is the most affected region. High-resolution computed tomography is of diagnostic value only in selected cases. Facial paralysis following local anesthesia is the most significant clinical sign. Vigilance in acute facial palsy after local anesthetics and in cholesteatoma surgery and adequate intraoperative exposure help to prevent iatrogenic injury of the uncovered nerve. In unclear cases, nerve monitoring can facilitate a safe outcome. [ABSTRACT FROM AUTHOR]

Occult malformations of the skull base are rare anomalies, but can cause severe complications such as meningitis. Detailed skull base investigations for detecting cerebrospinal fluid fistulas or celes are often not initiated until after a history of recurrent meningitis. We present a child first seen at the age of 12 with recurrent episodes of bacterial meningitis since early childhood, requiring antibiotic prophylaxis for years. High-resolution computed tomography revealed a chronic sinusitis and a bony defect on the right olfactory groove, while magnetic resonance imaging and CT-cisternography indicated no cerebrospinal fluid fistula or cele at that time. Endonasal surgery for chronic sinusitis was performed with a confirmed bony defect on the right olfactory groove and an olfactory fibre without its sleeve-like dura prolongation running into an adjacent ethmoidal cell, necessitating that it be covered. In the absence of any antibiotics a new episode of meningitis occurred 5 years after surgery. CT-cisternography and magnetic resonance imaging were repeated, now indicating a transclival bony defect with a meningocele in its proximal part, most probably presenting a canalis basilaris medianus. Endonasal surgery confirmed this bony defect after adenoidectomy, and closure was accomplished. No further meningitis has been observed for 2 years. Congenital skull base defects may be difficult to detect, but sufficient surgical closure after their precise delineation is mandatory to prevent infectious endocranial complications. The presence of more than one developmental skull base defect should be considered during careful radiological skull base evaluation, which has to include the clivus in order not to overlook rare basilar malformations. [ABSTRACT FROM AUTHOR]

Despite the relevance of the superficial musculoaponeurotic system (SMAS) in facial rejuvenation a clear anatomic definition of the SMAS is still lacking. Therefore, the morphology of the SMAS in 18 cadavers was investigated using different macroscopic and microscopic techniques. The region-specific anatomy of the SMAS is described in the forehead, parotid, zygomatic, and infraorbital regions, the nasolabial fold, and the lower lip. The SMAS is one continuous, organized fibrous network connecting the facial muscles with the dermis. It consists of a three-dimensional scaffold of collagen fibers, elastic fibers, and fat cells. Two different types of SMAS morphology were demonstrated: type 1 SMAS architecture is located lateral to the nasolabial fold with relatively small fibrous septa enclosing lobules of fat cells, whereas type 2 architecture is located medial to the nasolabial fold, where the SMAS consists of a dense collagen—muscle fiber meshwork. Overall, it was demonstrated that different facial regions show specific morphological characteristics, and thus region- specific surgical interventions may be necessary in facial rejuvenation. [ABSTRACT FROM AUTHOR]

Purpose: The failure rate for operative decompression in neurogenic thoracic outlet syndrome (NTOS) is high compared to more distal nerve compression syndromes, such as cubital or carpal tunnel syndrome. Herein, we aimed to determine if a more radical approach, namely costovertebral exarticulation of the first rib, may improve the postoperative results in patients with NTOS. Methods: From October 2002 to December 2020, 105 operative decompressions in 95 patients were evaluated; in 10 cases, decompressions were performed bilaterally. We presented the clinical outcomes of 59 exarticulations compared to those of 46 conventional resections. Evaluation was performed at a minimum of one year post-operation using the DASH questionnaire. Results: The exarticulation group presented with significantly better clinical outcomes (two-sample t-test assuming unequal variances, p < 0.001). Conclusions: This study showed that significantly better results were obtained when exarticulation of the first rib was performed in patients with NTOS. This finding supports the hypothesis that, in certain cases, the proximal portion of the first rib plays a pivotal role in the pathogenesis of NTOS. [ABSTRACT FROM AUTHOR]

Stress MRI brings together mechanical loading and MRI in the functional assessment of cartilage and meniscus, yet lacks basic scientific validation. This study assessed the response-to-loading patterns of cartilage and meniscus incurred by standardized compartmental varus and valgus loading of the human knee joint. Eight human cadaveric knee joints underwent imaging by morphologic (i.e., proton density-weighted fat-saturated and 3D water-selective) and quantitative (i.e., T1ρ and T2 mapping) sequences, both unloaded and loaded to 73.5 N, 147.1 N, and 220.6 N of compartmental pressurization. After manual segmentation of cartilage and meniscus, morphometric measures and T2 and T1ρ relaxation times were quantified. CT-based analysis of joint alignment and histologic and biomechanical tissue measures served as references. Under loading, we observed significant decreases in cartilage thickness (p < 0.001 (repeated measures ANOVA)) and T1ρ relaxation times (p = 0.001; medial meniscus, lateral tibia; (Friedman test)), significant increases in T2 relaxation times (p ≤ 0.004; medial femur, lateral tibia; (Friedman test)), and adaptive joint motion. In conclusion, varus and valgus stress MRI induces meaningful changes in cartilage and meniscus secondary to compartmental loading that may be assessed by cartilage morphometric measures as well as T2 and T1ρ mapping as imaging surrogates of tissue functionality. [ABSTRACT FROM AUTHOR]

Standard clinical MRI techniques provide morphologic insights into knee joint pathologies, yet do not allow evaluation of ligament functionality or joint instability. We aimed to study valgus stress MRI, combined with sophisticated image post-processing, in a graded model of medial knee joint injury. To this end, eleven human cadaveric knee joint specimens were subjected to sequential injuries to the superficial medial collateral ligament (sMCL) and the anterior cruciate ligament (ACL). Specimens were imaged in 30° of flexion in the unloaded and loaded configurations (15 kp) and in the intact, partially sMCL-deficient, completely sMCL-deficient, and sMCL- and ACL-deficient conditions using morphologic sequences and a dedicated pressure-controlled loading device. Based on manual segmentations, sophisticated 3D joint models were generated to compute subchondral cortical distances for each condition and configuration. Statistical analysis included appropriate parametric tests. The medial compartment opened gradually as a function of loading and injury, especially anteriorly. Corresponding manual reference measurements by two readers confirmed these findings. Once validated in clinical trials, valgus stress MRI may comprehensively quantify medial compartment opening as a functional imaging surrogate of medial knee joint instability and qualify as an adjunct diagnostic tool in the differential diagnosis, therapeutic decision-making, and monitoring of treatment outcomes. [ABSTRACT FROM AUTHOR]

While providing the reference imaging modality for joint pathologies, MRI is focused on morphology and static configurations, thereby not fully exploiting the modality's diagnostic capabilities. This study aimed to assess the diagnostic value of stress MRI combining imaging and loading in differentiating partial versus complete anterior cruciate ligament (ACL)-injury. Ten human cadaveric knee joint specimens were subjected to serial imaging using a 3.0T MRI scanner and a custom-made pressure-controlled loading device. Emulating the anterior-drawer test, joints were imaged before and after arthroscopic partial and complete ACL transection in the unloaded and loaded configurations using morphologic sequences. Following manual segmentations and registration of anatomic landmarks, two 3D vectors were computed between anatomic landmarks and registered coordinates. Loading-induced changes were quantified as vector lengths, angles, and projections on the x-, y-, and z-axis, related to the intact unloaded configuration, and referenced to manual measurements. Vector lengths and projections significantly increased with loading and increasing ACL injury and indicated multidimensional changes. Manual measurements confirmed gradually increasing anterior tibial translation. Beyond imaging of ligament structure and functionality, stress MRI techniques can quantify joint stability to differentiate partial and complete ACL injury and, possibly, compare surgical procedures and monitor treatment outcomes. [ABSTRACT FROM AUTHOR]

The most frequently used target for DBS in advanced Parkinson Disease (PD) is the sensorimotor subthalamic nucleus (STN), anatomically referred to as dorso-lateral STN [3]. Ambiguities arise, regarding the true meaning of this description in the STN. Does “dorsal” indicate posterior or superior? At its best, this definition assigns two directions in space to a three-dimensional structure. This paper evaluates the ambiguity and describes the sensorimotor part of the STN in stereotactic space. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) under mechanical loading, commonly referred to as stress MRI, allows the evaluation of functional properties of intra- and periarticular tissues non-invasively beyond static assessment. Quantitative MRI can identify physiological and pathological responses to loading as indication of, potentially treatable, early degeneration and load transmission failure. Therefore, we have developed and validated an MRI-compatible pressure-controlled axial loading device to compress human knee specimens under variable loading intensity and axis deviation. Ten structurally intact human knee specimens (mean age 83.2 years) were studied on a 3.0T scanner (Achieva, Philips). Proton density-weighted fat-saturated turbo spin-echo and high-resolution 3D water selective 3D gradient-echo MRI scans were acquired sequentially at 10° joint flexion in seven configurations: unloaded and then at approximately half and full body weight loading in neutral, 10° varus and 10° valgus alignment, respectively. Following manual segmentation in both femorotibial compartments, cartilage thickness (ThC) was determined as well as meniscus extrusion (ExM). These measures were compared to computed tomography scans, histological grading (Mankin and Pauli scores), and biomechanical properties (Instantaneous Young's Modulus). Compartmental, regional and subregional changes in ThC and ExM were reflective of loading intensity and joint alignment, with the greatest changes observed in the medial compartment during varus and in the lateral compartment during valgus loading. These were not significantly associated with the histological tissue status or biomechanical properties. In conclusion, this study explores the physiological in-situ response of knee cartilage and meniscus, based on stress MRI, and as a function of loading intensity, joint alignment, histological tissue status, and biomechanical properties, as another step towards clinical implementation. Image 1 • Stress MRI techniques allow functional assessment of knee joint structures. • A dedicated device for in-situ loading of human cadaveric knee joints was developed. • Imaging biomarkers, e.g. cartilage thickness, are related to loading parameters. • Loading intensity and alignment affect cartilage and meniscus responses to loading. • Histological and biomechanical measures are unrelated to responses to loading. [ABSTRACT FROM AUTHOR]

We present a case of a 29-year-old female complaining of right-sided watery nasal discharge. Radiological investigations identified an intrasphenoidal meningocele. The origin of the meningocele was pinpointed to the right parasellar region and was confirmed surgically. The parasellar bony defect appeared to be due to persistence of the lateral craniopharyngeal canal (Sternberg’s canal). Therefore, we assume a congenital origin for the intrasphenoidal meningocele found in the patient. Acquired bony defects of the sphenoid sinus are unlikely at the fusion planes of the different sphenoid bone components. Knowledge of the complex ontogeny of the sphenoid bone is an important key to differentiating between congenital and acquired sphenoid sinus meningoceles. [ABSTRACT FROM AUTHOR]

Study Design: A prospective experimental study. Purpose: This biomechanical in vitro study aimed to examine the extent to which the use of a rod persuader (RP) leads to additional mechanical stress on the screw–rod system and determine its influence on the bony anchoring of primary pedicle screws. Overview of Literature: Degenerative spine diseases and deformities are the most common indications for the stabilization and fusion of spinal segments. The pedicle screw–rod system is considered the gold standard for dorsal stabilization, and an RP is also increasingly being considered to fit the spondylodesis material. Methods: Ten lumbar spines from body donors were examined. Bisegmental dorsal spinal lumbar interbody fusion of the L3–L5 segments was performed using a pedicle screw–rod system (ROCCIA Multi-LIF Cage; Silony Medical, Germany). In group 1, the titanium rod was inserted without tension, whereas in group 2, the rod was attached to the pedicle screws at the L4 and L5 levels, creating a 5-mm gap. To attach the rod, the RP was used to press the rod into the pedicle screw. The rod was left in place for 30 minutes and then removed. Results: The rod reduction technique significantly increased the mechanical load on the overall construct measured by strain gauges (p<0.05) and resulted in outright implant failure with pedicle screw pullout in 88.9%. Conclusions: In cases where the spondylodesis material is not fully attached within the pedicle screw, an RP can be used with extreme caution, particularly in osteoporotic bones, to avoid pedicle screw avulsion and screw anchor failure. [ABSTRACT FROM AUTHOR]

Purpose: Imaging of the delicate inner ear morphology has become more and more precise owing to the rapid progress in magnetic resonance imaging (MRI). However, in clinical practice, the interpretation of imaging findings is hampered by a limited knowledge of anatomical details which are frequently obscured by artifacts. Corresponding review articles are as rare in journals as they are in reference books. This shortness prompted us to perform a direct comparison of imaging with anatomical whole-mount sections as a reference. It was the intention of this paper to compare the microscopic anatomy of a human inner ear as shown on anatomical whole-mount sections with high-resolution MRI and cone beam computed tomography (CBCT). Both are available in clinical routine and depict the structures with maximum spatial resolution. It was also a goal of this work to clarify if structures that were observed on MRI in a regular manner correlate with factual inner ear anatomy or correspond with artifacts typical for imaging. Methods: A fresh human anatomical specimen was examined on a clinical 3-Tesla MRI scanner using a dedicated surface coil. The same specimen was then studied with CBCT. In each imaging modality, high-resolution 3D data sets which enabled multiplanar reformatting were created. In the second step, anatomical whole-mount sections of the specimen were cut and stained. This process enabled a direct comparison of imaging with anatomical conditions. Results: Clinical MRI was able to depict the inner ear with remarkable anatomical precision. Strongly T2-weighted imaging protocols are exquisitely capable of showing the fluid-filled components of the inner ear. The macular organs, ampullar crests and cochlear aqueduct were clearly visible. Truncation artifacts are prone to be confused with the delicate membrane separating the endolymphatic from the perilymphatic compartment. However, it was not possible to directly depict this borderline. Conclusions: With the maximum resolution of magnetic resonance tomography, commonly used in everyday clinical practice, even the smallest details of the inner ear structures can be reliably displayed. However, it is important to distinguish between truncation artifacts and true anatomical structures. Therefore, this study can be useful as a reference for image analysis. [ABSTRACT FROM AUTHOR]

Objectives: Even 250 years after Beethoven's birth, the irrevocable cause of his hearing impairment remains unclear despite multiple publications by different professional groups. This study aimed to analyse the development of the most likely aetiologies during the last 100 years by a systematic review of the relevant medical literature. Methods: A systematic review of medical literature in PubMed®, PubMed Central®, and Web of Science® for the period 1920–2020 was conducted. Medical publications between 1920 and 1935 were additionally searched manually by review of reference lists. Studies were eligible when a statement regarding the most likely aetiology of the hearing loss of Beethoven was the aimed objective of the publication. Results: 48 publications were included. The following aetiologies were supposed: otosclerosis (n = 10), syphilis (n = 9), Paget's disease (n = 6), neural deafness (n = 5), immunopathy with inflammatory bowel disease, neural deafness with otosclerosis, sarcoidosis or lead intoxication (n = 2), and systemic lupus erythematosus, trauma, labyrinthitis or inner ear disease (n = 1). There is an ongoing effort with a mean publication frequency in this topic of 0.48/year. From 1920 to 1970, otolaryngologists were the group with the highest interest in this field (67%), whereas since 1971 most authors have belonged to non-otolaryngologic subspecialities (81%). Conclusion: Over the past 100 years, otosclerosis and syphilis were predominantly supposed to be the underlying causes. The hypothesis of syphilis—although rejected for a long time—has had a remarkable revival during the past 20 years. Regarding the outcome following therapeutic intervention by cochlear implantation, the differential diagnosis of neural deafness would be relevant today. [ABSTRACT FROM AUTHOR]

Quantitative MRI techniques such as T2 and T1ρ mapping are beneficial in evaluating knee joint pathologies; however, long acquisition times limit their clinical adoption. MIXTURE (Multi-Interleaved X-prepared Turbo Spin-Echo with IntUitive RElaxometry) provides a versatile turbo spin-echo (TSE) platform for simultaneous morphologic and quantitative joint imaging. Two MIXTURE sequences were designed along clinical requirements: "MIX1", combining proton density (PD)-weighted fat-saturated (FS) images and T2 mapping (acquisition time: 4:59 min), and "MIX2", combining T1-weighted images and T1ρ mapping (6:38 min). MIXTURE sequences and their reference 2D and 3D TSE counterparts were acquired from ten human cadaveric knee joints at 3.0 T. Contrast, contrast-to-noise ratios, and coefficients of variation were comparatively evaluated using parametric tests. Clinical radiologists (n = 3) assessed diagnostic quality as a function of sequence and anatomic structure using five-point Likert scales and ordinal regression, with a significance level of α = 0.01. MIX1 and MIX2 had at least equal diagnostic quality compared to reference sequences of the same image weighting. Contrast, contrast-to-noise ratios, and coefficients of variation were largely similar for the PD-weighted FS and T1-weighted images. In clinically feasible scan times, MIXTURE sequences yield morphologic, TSE-based images of diagnostic quality and quantitative parameter maps with additional insights on soft tissue composition and ultrastructure. [ABSTRACT FROM AUTHOR]

Introduction: Avoiding overlengthening in radial head arthroplasty (RHA) is essential for the prognosis of the elbow joint. An overlengthening from 2 mm is visible due to widening of the anterolateral ulnohumeral joint space but intraoperatively, this particular joint space is difficult to visualize. The commonly used Kocher approach allows visualization of the posterolateral joint space without additional instruments or further surgical release of the already unstable elbow. The aim of our study was to investigate whether the visualization of the posterolateral joint space is also a reliable method to indicate overlengthening in RHA. Material and methods: RHA was performed in five human cadaveric specimens with the forearm, wrist, and hand intact. The lateral ligament complex was detached and an anatomic transosseous refixation was performed. Six stages of implantation heights were documented: native joint (1), RHA at the anatomic height (2), + 2 mm (3), + 4 mm (4), + 6 mm (5) and − 2 mm (6). Macroscopic measurement and digital image analysis of the posterolateral and anterolateral ulnohumeral joint spaces were performed. Results: All stages of overlengthening showed a significant increase in posterolateral and anterolateral joint space widening (p < 0.05). The posterior and anterior joint space showed excellent intraclass correlation. Conclusion: Visualization of the posterolateral aspect of the ulnohumeral joint space is a reliable indicator for overlengthening in RHA without further compromising an already unstable elbow. Correlation to the findings of the anterolateral ulnohumeral joint space in different implants leads to the assumption that visualization of either the anterior or posterior ulnohumeral joint space is universally applicable to determine overlengthening in RHA, regardless of the type of the radial head implant. [ABSTRACT FROM AUTHOR]

Objectives: The present study aims to assess the impact of bilateral and high oblique sagittal split osteotomy (BSSO/HSSO), as well as displacement distances and directions on the expected and achievable bone contact area (BCA) and changes in the intercondylar distance (ICD). The primary question addressed is whether mandibular splitting through BSSO results in a greater BCA and/or ICD when compared to splitting through HSSO. Materials and methods: Totally 80 mandibular displacements were performed on 20 fresh cadavers, for each subject, four splints were produces to facilitate mandibular advancement as well as setbacks of 4 and 8 mm. Pre- and postoperative CBCT scans were performed to plan the surgical procedures and to analyze the expected and achieved BCA and ICD. Results: Regarding the maximum mandibular displacement, the expected BCA for HSSO/BSSO were 352.58 ± 96.55mm2 and 1164.00 ± 295.50mm2, respectively, after advancement and 349.11 ± 98.42mm2 and 1344.70 ± 287.23mm2, respectively, after setback. The achieved BCA for HSSO/BSSO were 229.37 ± 75.90mm2 and 391.38 ± 189.01mm2, respectively, after advancement and 278.03 ± 97.65mm2 and 413.52 ± 169.52 mm2, respectively after setback. The expected ICD for HSSO/BSSO were 4.51 ± 0.73 mm and 3.25 ± 1.17 mm after advancement and − 5.76 ± 1.07 mm and − 4.28 ± 1.58 mm after setback. The achieved ICD for HSSO/BSSO were 2.07 ± 2.9 mm and 1.7 ± 0.60 mm after advancement and − 2.57 ± 2.78 mm and − 1.28 ± 0.84 mm after setback. Significant differences between the BCA after HSSO and BSSO were at each displacement (p < 0.001), except for the achieved BCA after 8-mm setback and advancement (p ≥ 0.266). No significant differences were observed regarding ICD, except for the expected ICD after 8-mm setback and advancement (p ≤ 0.037). Conclusions: Compared to the virtual planning, the predictability regarding BCA and ICD was limited. ICD showed smaller clinical changes, BCA decreased significantly in the BSSO group. Clinical relevance: BCA and ICD might have been less important in choosing the suitable split technique. in orthognathic surgery. [ABSTRACT FROM AUTHOR]

Therefore, we completely agree with Brotto et al. that the hypothesis of chronic lead intoxication is a valuable explanation for Beethoven's progressive hearing impairment according to which the cause of his hearing loss would be neural rather than cochlear in origin. Another explanation might be lead-containing ointments which were used to close wounds after multiple ascites punctures at the end of Beethoven's life, at a time when Beethoven had already been considered almost completely deaf for more than 10 years. [Extracted from the article]

Magnetic resonance imaging (MRI) is commonly used to assess traumatic and non-traumatic conditions of the knee. Due to its complex and variable anatomy, the posterolateral corner (PLC)—often referred to as the joint's dark side—remains diagnostically challenging. We aimed to render the diagnostic evaluation of the PLC more functional by combining MRI, varus loading, and image post-processing in a model of graded PLC injury that used sequential transections of the lateral collateral ligament, popliteus tendon, popliteofibular ligament, and anterior cruciate ligament. Ten human cadaveric knee joint specimens underwent imaging in each condition as above, and both unloaded and loaded using an MR-compatible device that standardized loading (of 147 N) and position (at 30° flexion). Following manual segmentation, 3D joint models were used to computationally measure lateral joint space opening for each specimen, configuration, and condition, while manual measurements provided the reference standard. With more extensive ligament deficiency and loading, lateral joint spaces increased significantly. In conclusion, varus stress MRI allows comprehensive PLC evaluation concerning structural integrity and associated functional capacity. Beyond providing normative values of lateral compartment opening, this study has potential implications for diagnostic and surgical decision-making and treatment monitoring in PLC injuries. [ABSTRACT FROM AUTHOR]