Center Of Head Research Articles

Quality Issues in Kinematic Traces from Three Head Impact Sensors in Boxing: Prevalence, Effects, and Implications for Exposure Assessment.

When used in-vivo or in biofidelic environments, many head impact sensors have shown limitations related to the quality and validity of the kinematics measured. The objectives were to assess the quality of kinematic traces from three head impact sensors, determine the effects of signal quality on peak accelerations, and compare measurements across sensors. Head impacts were collected with instrumented mouthguards, skin patches, and headgear patches during boxing sparring. The quality of the raw kinematic traces for 442 events for each sensor was categorized using pre-defined objective criteria into high, questionable, and low-quality classes. The proportion of high-quality recordings was analyzed by participant, type of impact, and impact location. Associations between signal quality and peak kinematics were assessed within each sensor, and peak kinematics (resolved to the head center of gravity) were compared between sensors. High-quality criteria were met in 53%, 20%, and 26% of events for the mouthguard, skin patch, and headgear patch, respectively. High-quality recordings were less frequent for impacts occurring close to the sensor (e.g., 30% vs. 61% for the mouthguard) and showed lower peak kinematics than low-quality recordings (p < 0.001). Despite careful selection of high-quality simultaneous recordings, there was little to no association between the sensors' measurements (Spearman's p ≥ 0.043). The kinematic data often reflected the motion of the sensor itself rather than the motion of the head, overestimating head impact magnitude. Researchers should evaluate data quality prior to analyzing kinematics or injury severity metrics. Comparison of data across studies or in relation to injury risk functions needs to be done with caution when data were acquired from different sensors.

Biological total hip arthroplasty combined with impacting bone grafting for the treatment of moderate to severe acetabular invagination secondary to rheumatoid arthritis

To explore the surgical technique and clinical outcomes of biological total hip arthroplasty(THA) combined with impacting bone grafting for the treatment of moderate to severe acetabular invagination secondary to rheumatoid arthritis(RA). Total of 20 patients(28 hips) with RA secondary to acetabular invagination were treated with THA of bioprosthesis combined with autogenous bone grafting from January 2012 to October 2020, including 5 males(8 hips) and 15 females(20 hips) with an average age of (55.10±4.96) years old from 45 to 64 years old. The depth of acetabular invagination was 8.43 to 16.25 mm with an average of (11.91±2.59) mm. According to Sotello-Garza and Charnley classification criterion, there were 15 cases(23 hips) of type Ⅱ(protrusio acetabuli 6 to 15 mm), and 5 cases(5 hips) of type Ⅲ(protrusio acetabuli>15 mm). Autologous femoral head granular bone and(or) allograft impacting grafting were used to reconstruct the acetabum, the biological porous acetabular cup was fixed by pressure fitting. At the postoperative follow-up, the activity function of the hip joint, the length of both lower limbs, VAS and Harris score were evaluated, and the healing of bone graft, the restoration of the hip rotation center and loosening of prosthesis were assessed by X-ray. The operation time was 75 to 160 min with anverage of (103.32±18.18) min, the intraoperative blood loss was 150 to 650 ml with an average of (319.64±122.61) ml. There were no neurovascular complications during the operation. All patients were followed up from 2 to 10 years with an average of (5.45±2.50) years. The horizontal distance between the center of femoral head and the Kohler's line was increased from (11.40±1.85) mm preoperatively to (25.99±2.56) mm at the final follow-up(P<0.01), and the vertical distance between the center of femoral head and the line joining bilateral ischial tuberosities was decreased from (89.36±5.20) mm preoperatively to (71.84±3.55) mm at the final follow-up(P<0.01). The range of flexion motion of hip joint increased from (44.43±10.57)° preoperatively to (98.75±12.52)° at the final follow-up(P<0.01), the range of abduction motion of hip joint increased from (12.50 ±6.01)°preoperatively to final follow-up (32.82±5.39)°(P<0.01). The discrepancy of both lower limbs was significantly decreased from (19.39±5.93) mm preoperatively to (6.64±2.87) mm at the final follow-up(P<0.01). The VAS decreased from (5.36±0.78) preoperatively to (1.82±0.86) at the final follow-up(P<0.05), and the Harris score increased from (41.39±7.77) preoperatively to (89.00±4.67) at the final follow-up(P<0.01). All the patients could move independently without assistance. Among them, 2 patients(2 hips) had hip pain after exercise, and 1 patient(1 hip) suffered from periprosthetic fracture due to fall. Autologous femoral head granular bone grafting can reconstruct the acetabulum, and restore the rotation center of the hip joint, combined with biological porous tantalum/titanium acetabular cup can achieve good short-and medium-term outcomes in the treatment of moderate to severe acetabular invagination secondary to rheumatoid arthritis.

Topical Anesthesia in Cutaneous Head and Neck Surgery: A Randomized Controlled Trial.

Cutaneous head and neck surgery can safely and effectively be performed using local anesthetic (LA). However, optimizing pain management during LA administration is paramount for patient comfort and procedural efficacy. The primary objective of this study was to investigate the comparative effectiveness of EMLA cream and ethyl chloride (EC) spray in mitigating pain associated with LA administration in cutaneous head and neck surgery. Randomized controlled trial. University-affiliated tertiary head and neck oncology center. Sample size calculation was performed followed by computer randomization into the following groups: EMLA, EMLA placebo (aqueous cream), EC, and a control group (no topical agent). Demographics, pain, and procedural experience scores were recorded perioperatively. Statistical analysis was performed to analyse differences between groups utilizing the Mann-Whitney U test, Kruskall-Wallis test, Chi-square test, and Spearman's Rho. 121 cutaneous lesions with a median patient age of 76 were analyzed. There were no statistically significant differences in pain scores (median [IQR]) between patients receiving EMLA (4 [3.75]), EMLA placebo (4.8 [3.6]), EC (5.8 [2.8]), and no treatment (5 [4.1], P = .19). Procedural experience scores were clinically similar (P = .02). Risk factors associated with elevated nociceptive sensitivity were surgical site (scalp, P = .01), malignant lesions (P < .01) and lesion surface area (rs = 0.22, P = .01). EMLA and EC did not mitigate LA-associated pain in patients undergoing cutaneous head and neck surgery and as such practitioners should reconsider their use of these in this regard. Patients' operative experience remains excellent regardless of topical anesthetic use. Ib.

Treatment regimens for laryngeal and hypopharyngeal squamous cell carcinoma: a "real life" multicenter study of 2307 patients.

This retrospective multicenter study aimed to evaluate surgical versus conservative treatment in patients with hypopharyngeal and laryngeal cancer under real world conditions. This study included 2307 patients diagnosed with hypopharyngeal or laryngeal squamous cell carcinoma (SCC) in five German tertiary head and neck centers between 01/2004 and 12/2014. Overall, 783 patients with advanced SCC consecutively underwent laryng(opharyng)ectomy (L(P)E). Patient chart data regarding age, sex, tumor location, TNM status, grading, indication for L(P)E, treatment modalities, R status, postoperative complications, and hospitalization time were analyzed. Patients with lacking data and incomplete staging and those who refused treatment or did not comply with the recommended treatment were excluded from survival analysis. A slight but significant increase was observed in L(P)E, referring to an increasing rate of tumor recurrence. While T1/2N0M0 laryngeal and hypopharyngeal cancer patients showed comparable overall survival (OS) for surgical and conservative treatment, surgery showed significantly better OS in lymph node-positive individuals and locally advanced tumor stages. Tumor recurrence occurred in more than one-third of the cases. In particular, in early glottic cancer recurrence, L(P)E represents a curative and safe treatment option, whereas in supraglottic and hypopharyngeal cancer, L(P)E was associated with reduced survival rates. Notably, 36% of patients with supraglottic cancer and 59% of patients with hypopharyngeal cancer recurrence could only be treated with palliative care. Comparable survival rates were demonstrated for cT1/2N0M0 laryngeal and hypopharyngeal SCC compared with primary chemo-/radiotherapy and larynx-preserving surgery. Better OS was achieved after surgery in nodal-positive patients and in those with locally advanced disease. Tumor recurrence should be anticipated in up to 39% of cases. Glottic cancer recurrence can be successfully and safely treated with L(P)E, whereas OS is reduced in hypopharyngeal cancer and possibly in supraglottic cancer.

Геоинформационная система глазного дна

Purpose. To develo fundus operational geoinformation system for accurate topographic identification of the pathological process characteristics. Material and methods. An operational digital fundus geoinformation system was developed using available program «Transporter Online». A digital fundus photograph of the patient with active retinopathy of prematurity (ROP), obtained with a «RetCam» retinal camera, was placed in a cartesian field. Next, taking the center of the optic nerve head (ONH) as the zero point, we built parallels with a step equal to one optic disc radius and meridians with a step of 10 degrees by analogy with the TABO scale (Technische Ausschuss fur Brillen – Optik). Results. As a result, a geoinformation system of the fundus was built in the form of a coordinate grid comparable to a geographic coordinate system. Using the developed system, it is possible to measure many parameters on the retina. As the developed system is used, the number and information content of the parameters will undergo changes depending on the assigned tasks. It is possible to use the fundus geoinformation system for any retinal pathology, in particular for active ROP. To eliminate the influence of the scale factor and the reliability of quantitative indicators of image magnification, digitization is carried out based on the results of measuring angles and linear dimensions in «units» of the optic disc radius, which determines the individuality and originality of the proposed system. Conclusion. The proposed fundus geoinformation system will provide accurate topographic identification of the pathological process characteristics on the retina surface. The obtained coordinates of the fundus structures, which are of research interest, will form an operational navigation system that will significantly facilitate the work of ophthalmologists in transmitting information, analyzing the dynamics and outcomes of the pathological process, and can also be as the basis for a further transition to artificial intelligence use. Key words: retina, fundus, topography, geoinformation system

Glenohumeral joint kinematics during apprehension-relocation test in patients with anterior shoulder instability and glenoid bone loss.

This study aimed to quantify the shoulder kinematics during an apprehension-relocation test in patients with anterior shoulder instability (ASI) and glenoid bone loss using the radiostereometric analysis (RSA) method. Kinematics were compared with the patient's contralateral healthy shoulder. A total of 20 patients with ASI and > 10% glenoid bone loss and a healthy contralateral shoulder were included. RSA imaging of the patient's shoulders was performed during a repeated apprehension-relocation test. Bone volume models were generated from CT scans, marked with anatomical coordinate systems, and aligned with the digitally reconstructed bone projections on the RSA images. The glenohumeral joint (GHJ) kinematics were evaluated in the anteroposterior and superoinferior direction of: the humeral head centre location relative to the glenoid centre; and the humeral head contact point location on the glenoid. During the apprehension test, the centre of the humeral head was 1.0 mm (95% CI 0.0 to 2.0) more inferior on the glenoid for the ASI shoulder compared with the healthy shoulder. Furthermore, the contact point of the ASI shoulder was 1.4 mm (95% CI 0.3 to 2.5) more anterior and 2.0 mm (95% CI 0.8 to 3.1) more inferior on the glenoid compared with the healthy shoulder. The contact point of the ASI shoulder was 1.2 mm (95% CI 0.2 to 2.6) more anterior during the apprehension test compared to the relocation test. The humeral head centre was located more inferior, and the GHJ contact point was located both more anterior and inferior during the apprehension test for the ASI shoulders than the healthy shoulders. Furthermore, the contact point displacement between the apprehension and relocation test revealed increased joint laxity for the ASI shoulder than the healthy shoulders. These results contribute to existing knowledge that ASI shoulders with glenoid bone loss may also suffer from inferior shoulder instability.

Physiological rotation patterns of the thoracolumbar spine across different ages: A detailed analysis using upright CT

BackgroundThe rotational motion of the spine plays a crucial role in daily activities. Understanding the mechanisms of spinal rotation is essential for evaluating normal spinal function, especially in standing positions due to the influence of gravity. However, previous studies on spinal rotation have been limited. Research QuestionWhat are the differences in thoracolumbar rotation during trunk rotation in a standing position among different age and gender groups? MethodsThis cross-sectional study involved 49 healthy volunteers without back pain, including 24 younger participants (13 males, 11 females) and 25 elderly participants (12 males, 13 females). Upright and trunk-rotated CT (right-rotated standing positions) scans were taken. Vertebral rotation was measured using the femoral head center as an axis. ResultsAnalysis of spinal alignment in the standing position revealed mild rotation from the lumbar to thoracic vertebrae. The lumbar spine exhibited left rotation at apex of L3 (L3: −1.3±3.8°, p=0.01), while the lower thoracic spine showed right rotation at apex of T8 (T8: 1.9±2.4°, p<0.001) and the upper thoracic spine showed left rotation at apex of T3 (T3: −2.6±2.9°, p<0.001). The lumbar spine showed minimal rotation during maximum trunk rotation, with significant rotation noted above T10 (16 % vs 84 %). The total thoracolumbar spinal rotation at T1 showed significant differences by gender and age (male vs. female: 23.9±° vs. 30.3±°, p=0.001; young vs. elderly: 29.2±° vs. 25.0±°, p=0.028; elderly male vs. elderly female: 19.2±° vs. 30.4±°, p<0.001). Younger participants did not show significant gender differences, while elderly females retained more rotation compared to males. SignificanceThis pioneering study provides the first detailed report on the range of spinal rotation in a physiological standing situation, highlighting significant differences by gender and age. These findings offer new insights into the natural patterns of spinal rotation and their potential implications for diagnosing and treating spinal disorders.

Management of Giant Thyroid Tumors in Patients with Multiple Comorbidities in a Tertiary Head and Neck Surgery Center.

Background/Objectives: The thyroid gland can represent the seat of development for giant tumors exceeding 10 cm in diameter. A retrospective analysis on 21 cases of giant thyroid tumors with comorbidities, operated in the ENT Department of the Bucharest University Emergency Hospital has been conducted. Methods: Giant benign tumors accounted for 28.57% of the cases studied and reached gigantic volumes in an average time interval of 3 years, with an average resection piece weight of 318 g. Malignant tumors accounted for 71.43%, with an average duration of evolution of 7 years, with an average resection piece weight of 581 g. Results: Dysphagia was present in all patients, dyspnea in 47.61% and dysphonia in 38.09% of cases. Total thyroidectomy is the gold standard in giant thyroid tumors, associated with radical neck dissection, extended to groups VI and VII in malignant tumors. In 10 of 11 cases of giant malignant thyroid tumors (90.90%), without anaplastic thyroid carcinoma, the survival at 5 years after multimodal oncologic treatment was favorable. Anticoagulant treatment increased the risk of postoperative reversible recurrent laryngeal nerve lesion. Conclusions: The management of giant thyroid tumors in patients with multiple comorbidities needs a multidisciplinary team including endocrinologist, radiologist, anesthesiologist, pathologist, ENT surgeon, thoracic surgeon, oncologist and radiotherapist.

T1 Pelvic and Lumbar Pelvic Angles Normative Values: A Prospective Cohort Study of 472 Asymptomatic Volunteers.

Cross-sectional analysis of a prospectively enrolled cohort. Determine the normative values of the T1 Pelvic Angle (TPA) and Lumbar Pelvic Angle (LPA) in an asymptomatic cohort of volunteers. The TPA and LPA have been introduced as sagittal spino-pelvic parameters to guide correction of adult spinal deformity. Suggested values for these parameters were derived from linear regressions based on Oswestry Disability Index scores from adult spinal deformity patients. While a few studies have evaluated the normative value of TPA, none have evaluated the LPA in asymptomatic individuals. TPA and LPA were measured on radiographs of 472 asymptomatic volunteers between 20 and 40 years old. TPA and LPA were calculated as originally described from the centroid of T1 and L1 respectively, to the center of the femoral head to the midpoint of the sacral endplate. TPA and LPA were also evaluated using the midpoint of the superior endpoint as a surrogate to the centroid of the vertebra to compare these two measurement techniques. TPA and LPA normative values were respectively 7.3 [6.8-7.8] and 6.3o [5.9-6.7]. There was no statistically significant difference between using the centroid of T1 or L1 versus using the midpoint of the superior endplate with respective results of 7.5o [7.0-8.0] (P=0.55) and 6.1o [5.6-6.5] (P=0.43). TPA was significantly different between Roussouly types 1-2-3 versus type 4 with respective results of of 6.7o, 7.2o, 6.5o and 9.2o (P<0.001). The same difference was observed for the LPA with normative results of 3.8o, 5.1o, 5.8o and 9.3o (P<0.001), respectively, for Roussouly types 1,2,3 and 4. TPA and LPA normative values are 7o and 6o, respectively, and vary between Roussouly morphotypes 1,2 and 3 versus type 4. Using the midpoint of the superior endplate of T1 and L1 versus the centroid yielded similar results and therefore could be easier to use intraoperatively.

Joint-line obliquity angle is significantly affected by hip abduction and adduction: A simulated analysis.

Different methods for quantifying joint-line obliquity (JLO) have been described, including joint-line obliquity angle (JLOA), Mikulicz joint-line angle (MJLA) and medial proximal tibial angle (MPTA). The goal of the present study was to quantify the variation of JLOA based on the position of the hip. The hypothesis of our study is that JLO is significantly influenced by the abduction/adduction of the limb, unlike MJLA. One hundred long-leg-weightbearing X-rays were used. At time 0 and after 30 days, two observers performed different measurements, including (1) distance between pubic symphysis and center of the femoral head, (2) distance between center of the femoral head and center of the ankle joint, (3) distance between center of the ankle and medial malleolus, (4) hip-knee-ankle angle, (5) MPTA, (6) lateral distal femoral angle, (7) joint-line congruency angle, (8) JLOA, (9) MJL and (10) angle between Mikulicz line and line perpendicular to the ground. The changes of the JLOA based on the position of the hip (abducted, neutral, bipedal stance adduction and monopodal stance adduction) were calculated with trigonometric formulas and with simulation on an orthopaedic planning digital software. The JLOA change between adducted and abducted positions was on average 12.8° (SD 0.9 mm). The MJL did not vary significantly based on hip position. The adduction/abduction of the lower limb has a considerable impact on JLOA. Methods like MJLA which are not affected by hip position should be preferred for JLO evaluation. Diagnostic study, level III.

How Do Changes in Femoral Anteversion Impact Femoral Rotation and Anterior Offset After Total Hip Arthroplasty?

BackgroundThe impact of femoral anteversion changes on femoral rotation and anterior offset following total hip arthroplasty (THA) has not been well studied. This study therefore investigated the relationship among femoral anteversion, anterior offset, and femoral rotation before and after THA. MethodsThere were 995 patients who had staged primary bilateral THAs who received a preoperative supine computerized axial tomography (CT) scan, following a standardized protocol, for surgical planning prior to each THA. The following measurements were performed for the first operative hip preoperatively and postoperatively on the first and second CT scans, respectively: femoral anatomic anteversion, defined as the angle between the native femoral neck or stem neck axis and the posterior condylar axis; femoral rotation, defined as the angle of the posterior condylar axis relative to the coronal plane of the CT; and femoral anterior offset, defined as the shortest distance between the femoral head center and a femoral plane containing the epicondyles and the piriformis fossa. The mean time between imagings was 11 months (range, 2 to 44). Associations are described using linear regression (β = slope) and Pearson correlation (r) coefficients. A t distribution was used for testing correlation. ResultsFemoral anteversion correlated with femoral anterior offset preoperatively (β = 0.565, r = 0.914, P < 0.001) and postoperatively (β = 0.671, r = 0.958, P < 0.001), and with femoral rotation preoperatively (β = 0.623, r = 0.575, P < 0.001) and postoperatively (β = 0.459, r = 0.517, P < 0.001). Increasing anteversion from preoperatively to postoperatively increased anterior offset (β = 0.621, r = 0.908, P < 0.001) and femoral internal rotation (IR) (β = 0.241, r = 0.273, P < 0.001). Patients who had >20° increase in anteversion (mean increase 26°, range 20 to 40.5°, n = 71) had a mean increase in femoral IR of 9.6 ± 9.8°. ConclusionsIncreasing femoral anteversion increases anterior offset and IR of the femur, with approximately a 1° increase in IR for every 4° increase in anteversion on average. Surgeons should appreciate the implications of changing anteversion during THA planning.

Nonspherical humeral arthroplasty increases internal rotation: a biomechanical comparison of the native humeral head to nonspherical and spherical humeral implants

BackgroundNonspherical humeral head implants more closely resemble native humeral anatomy than spherical components and may better replicate native shoulder range of motion (ROM) and kinematics. The purpose of this study was to compare shoulder ROM and kinematics of a commercially available nonspherical humeral head implant with the native humeral head and a height matched, custom manufactured spherical implant. MethodsSix fresh frozen cadaveric shoulder specimens were used with a custom shoulder testing system. The native shoulder was tested in multiple positions under anatomic muscle loading. Each specimen was tested for ROM and glenohumeral joint kinematics by measuring the humeral head apex and humeral head center (HHC) translation per degree of rotation using a MicroScribe digitizer. Measurements were then repeated after implantation of a spherical and, subsequently, a nonspherical humeral head prothesis. ResultsThe nonspherical implant had significantly more internal rotation (IR) compared to the spherical implant at 0° abduction (10.6 ± 6.2° more IR, P = .004, 95% confidence interval [CI]: −13.3, 34.5), 30° abduction (5.7 ± 2.8°, P = .009, 95% CI: −12.6, 24.0) and 60° abduction (6.8 ± 2.7°, P = .002, 95% CI: −8.3, 22.1) in the scapular plane, and 60° abduction (6.9 ± 2.0°, P = .031, 95% CI: −12, 25.6) in the coronal plane. The nonspherical implant had more IR than the native head at 60° of abduction in the scapular plane (7.0 ± 2.2° P = .002, 95% CI: −10.3, 24.3). The spherical head had less IR than the native head at 0° abduction (7.2 ± 4.8°, P = .031, 95% CI: 32.5, 18.1). There were no differences in humeral head apex translation per degree of rotation noted between the spherical implant or nonspherical implant and the native shoulder. The nonspherical head had less HHC translation than the native shoulder at 30° abduction in the forward flexion plane (P = .007); otherwise, there were no statistically significant differences in HHC translation between the native shoulder, the spherical head, and the nonspherical head. There was no significant difference observed between the average difference in anterior-posterior and superior-inferior radius of curvature of the nonspherical implants (2.0 ± 0.7 mm) and the native humeral heads (1.9 ± 1.3 mm) [P = .926]. ConclusionThe results of this biomechanical study suggest that the commercially available nonspherical humeral head has improved IR when compared to a custom, height controlled spherical implant and offers ROM and kinematics similar to the native humeral head in a cadaveric model.

Evaluation of Two Clinical Stem-Fit Philosophies Within the Femoral Canal Using a Preoperative Planning Tool: Could a Hybrid Approach Be Best?

BackgroundTotal hip arthroplasty (THA) has transformed patient lives, yet evolving expectations and the number of postoperative foot angle changes have underscored the need for precise component positioning. The objective of this study was to use 3-dimensional (3D) preoperative planning to evaluate stem alignment and orientation for three THA systems using two different stem-fit algorithms. It was hypothesized that the different stem alignments would yield similar changes in stem orientation and placement within the canal for all 3 systems. MethodsThis study introduced a novel 3D preoperative planning tool, comparing two different surgical stem-fit philosophies within the canal: “canal fit” (CF) and “anatomical fit” (AF). We virtually implanted 10 subjects with three different THA implant systems using both philosophies, evaluating 60 total fits within the canals. The CF philosophy aimed to minimize cortical bone removal. In contrast, the AF philosophy prioritized aligning the implanted head with the anatomical head center. ResultsDetailed analyses revealed that AF led to fixation occurring mainly on the medial aspect of the stem, while CF exhibited a more even distribution between medial and lateral sides. The AF philosophy achieved significantly closer placement of the implanted head to the anatomical center (2.0 to 2.1 mm) compared to the CF philosophy (3.0 to 6.0 mm) (P < 0.01). The AF resulted in neutral stem orientation (0°) across all stems, whereas the CF exhibited greater malrotation (2.0 to 7.0°) (P < 0.02). The AF required more bone removal (0.13 to 0.46 cm³) than the CF (0.02 to 0.06 cm³) (P < 0.01). ConclusionsThe findings underscore the importance of 3D planning, emphasizing its potential to improve stem version alignment in THA. The results from this study may advocate 3D preoperative planning with robotic surgery to plan stem placement within the canal while maintaining anatomical femoral head restoration.

A finite element analysis of patellofemoral joint biomechanics: Exploring potential causes of postoperative anterior knee pain following unicompartmental knee arthroplasty

PurposeAnterior knee pain is a common complication following unicompartmental knee arthroplasty (UKA). This study aimed to elucidate the mechanism of anterior knee pain after UKA by examining the biomechanical characteristics of the patellofemoral joint. MethodsThis study employs the finite element analysis method. A healthy model of the right lower limb was created using CT scans of an intact right lower limb from a healthy woman. Based on this model, a preoperative pathological model was generated by removing the meniscus and part of the articular cartilage. The UKA prosthesis was then applied to this model with five different bearing thicknesses: 5 mm, 7 mm, 10 mm, 11 mm, and 13 mm. To simulate various degrees of knee joint flexion, the femur was rotated relative to the knee joint's rotational axis, producing lower limb models at flexion angles of 0°, 30°, 60°, 90°, and 120°. We applied a constant force from the center of the femoral head to the center of the ankle joint to simulate lower limb loading during squatting. The simulations were conducted using Ansys 17.0. ResultsBoth overstuffing and understuffing increased the peak stress on the patellar cartilage, with overstuffing having a more pronounced effect. Compared to healthy and balanced models, overstuffed and understuffed models exhibited abnormal stress distribution and stress concentration in the patellar cartilage during knee flexion. ConclusionOverstuffing and understuffing lead to residual varus or valgus deformities after UKA, causing mechanical abnormalities in the patellofemoral joint. These abnormalities, characterized by irregular stress distribution and excessive stress, result in cartilage damage, exacerbate wear in the patellofemoral joint and consequently lead to the occurrence of anterior knee pain.

Airway consequences of alendronic acid aspiration.

Bisphosphonates are commonly prescribed medications to prevent and treat osteoporosis. Although possessing low side effect profiles, the potential for severe topical effects is rare but important. Irritation of the upper gastrointestinal tract is well documented; however, the risk and effects of accidental aspiration are rarely reported.Attention is drawn to a case recently managed at a tertiary head and neck centre where a patient in their 70s was admitted in respiratory distress 3 days after aspirating alendronic acid. This case highlights the potential risk of topical chemical injury posed to the airway by bisphosphonates.Bisphosphonates should be prescribed with detailed and specific counselling regarding this risk. Pharmacological product literature should be updated to reflect the risk. Clinical teams should be aware of and vigilant for the delayed presentation and prolonged symptom course of such injuries. Prompt airway intervention and techniques to minimise further mucosal trauma ensure optimal outcomes.

The multicenter registry "oropharyngeal cancer" of the German ENT Study Center - First Results

The number of oropharyngeal squamous cell carcinomas (OPSCC) caused by human papillomavirus (HPV) has increased significantly in recent years. However, no robust data exist on the incidence of HPV-associated OPSCC as well as their treatment in central Europe. The aim is to establish an epidemiological register of patients with OPSCC in central Europe. To close the evidence gap on p16-positive OPSCC, a prospective multicenter registry on incidence, risk factors and treatment of OPSCC in certified Head and Neck Tumor Centers according to the German Cancer Society was established. Data collection was pseudonymously performed using the web-based Research Electronic Data Capture (REDCap). In 2022 and 2023, 1312 patients with OPSCC from 34 centers were included. 720 patients (58.2 %) were p16-positive. The most common locations of p16-positive primary tumors were the tonsil (49.9 %) and the base of the tongue (28.7 %). 63.1 % of p16-positive OPSCC received primary surgical treatment, whereas only 48.0 % of p16-negative tumors received primary surgery. Differences are also evident in the adjuvant therapy: 58 % of p16-negative OPSCC did not receive adjuvant therapy after surgery, compared with 37.1 % of p16-positive OPSCC. The start of the OPSCC registry study was technically smooth. This registry provides an insight into the current care situation of OPSCC in German-speaking countries and will gain importance through the participation of more centers.

Methods for three-dimensional characterization of the acetabulum prior to pelvic reorientation osteotomy: a scoping review.

Periacetabular osteotomy is the gold standard treatment for acetabular dysplasia. The great variability of acetabular dysplasia requires a personalized preoperative planning improved by 3D reconstruction and computer-assisted surgery. To plan the displacement of the acetabular fragment by a pelvic osteotomy, it is necessary to define a reference plane and a method to characterize 3D acetabular orientation. A scoping review was performed on PubMed to search for articles with a method to characterize the acetabulum of native hips in a 3D reference frame. Ninety-eight articles out of 3815 reports were included. Three reproducible reference planes were identified: the anterior pelvic plane, the Standardization and Terminology Committee plane used in gait analysis, and the sacral base plane. The different methods for 3D analysis of the acetabulum were divided in four groups: global orientation, triplanar measurements, segmentation, and surface coverage of the femoral head. Two methods were found appropriate for reorientation osteotomies: the global orientation by a vector method and the triplanar method. The global orientation method relies on the creation of a vector from the acetabular rim, from the acetabular surface or from successive planes. Normalization of the global acetabular vector would correct acetabular dysplasia by a single alignment maneuver on an ideal vector. The triplanar method, based on angle measurements at the center of the femoral head, would involve correction of anomalies by considering axial, frontal, and sagittal planes. Although not directly fit for reorientation, the two others would help to candidate patients and verify both planning and postoperative result.

MYB immunohistochemistry as a predictor of MYB::NFIB fusion in the diagnosis of adenoid cystic carcinoma of the head and neck

Diagnosing adenoid cystic carcinoma (AdCC) is challenging due to histopathological variability and similarities with other tumors. In AdCC pathogenesis, the cellular myeloblastosis gene (c-MYB) often exhibits a MYB::NFIB fusion from a reciprocal translocation. This study aimed to assess the predictive accuracy of MYB immunohistochemistry for detecting this translocation compared to fluorescence in situ hybridization (FISH). This study included 110 AdCC patients (1999-2017) from two Dutch head and neck centers using tissue microarrays and full slides. Median MYB expression levels by immunohistochemistry were compared based on translocation status by FISH, and differences within clinicopathological parameters were examined. An immunohistochemical cut-off was established to estimate the translocation. MYB immunohistochemistry was available in 90/110 patients, with a median expression of 27%. FISH was interpretable in 79/108 tumors, identifying MYB::NFIB fusion in 44 (56%). Among 62 patients with both MYB expression and translocation data, the fusion was present in 38 (61%). These tumors had higher MYB expression (30%) than nontranslocated tumors (6%); P = .02. A 60% MYB expression cut-off yielded 100% specificity for detecting the translocation but had no prognostic value. Although MYB protein expression alone lacks diagnostic precision, protein expression >60% predicted the MYB::NFIB fusion in all tumors.

The predominant insertion of the ischiofemoral ligament is a merging to the iliofemoral ligament as demonstrated on magnetic resonance arthrogram studies.

The capsular ligaments at the hip joint work in synchrony with the acetabulum and femoral head for articular stability. There is a lack of understanding about ischiofemoral ligament (ISFL) anatomy and function. To assess the insertion of the ISFL in non-arthritic adult hips. A retrospective analysis was performed in 72 patients who underwent magnetic resonance arthrogram (MRA) for the assessment of hip pain. The distribution of the ISFL components, the thickness, and the insertion site were assessed by concomitantly using the axial oblique, coronal, and sagittal MRA images. Two insertions of the ISFL anterior to the center of the femoral head were identified in 71 (99%) hips: (i) predominant anterior merging with the iliofemoral ligament as continuation of zona orbicularis, observed in all hips; and (ii) anterolateral junction of femoral neck and greater trochanter. Two ISFL parts (proximal and distal) were identified in 70 (97%) of the 72 studied hips. The proximal part was always thinner (mean 2.6 ± 0.7 mm) and originated from the ischium at the acetabular rim. The distal part was a continuation of the zona orbicularis, and the mean thickness was 6.7 ± 1.6 mm. Both parts merged as they coursed over the superior portion of the femoral head. The predominant insertion of the ischiofemoral ligament is a merging to the iliofemoral ligament anteriorly. Surgical procedures such as hip arthroscopy involving the ISFL will affect the function of the iliofemoral ligament, and vice versa.

Accuracy of Instrumented Mouthguards During Direct Jaw Impacts Seen in Boxing.

Measuring head kinematics data is important to understand and develop methods and standards to mitigate head injuries in contact sports. Instrumented mouthguards (iMGs) have been developed to address coupling issues with previous sensors. Although validated with anthropomorphic test devices (ATDs), there is limited post-mortem human subjects (PMHS) data which provides more accurate soft tissue responses. This study evaluated two iMGs (Prevent Biometrics (PRE) and Diversified Technical Systems (DTS) in response to direct jaw impacts. Three unembalmed male cadaver heads were properly fitted with two different boil-and-bite iMGs and impacted with hook (4m/s) and uppercut (3m/s) punches. A reference sensor (REF) was rigidly attached to the base of the skull, impact kinematics were transformed to the head center of gravity and linear and angular kinematic data were compared to the iMGs including Peak Linear Acceleration, Peak Angular Acceleration, Peak Angular Velocity, Head Injury Criterion (HIC), HIC duration, and Brain Injury Criterion. Compared to the REF sensor, the PRE iMG underpredicted most of the kinematic data with slopes of the validation regression line between 0.72 and 1.04 and the DTS overpredicted all the kinematic data with slopes of the regression line between 1.4 and 8.7. While the PRE iMG was closer to the REF sensor compared to the DTS iMG, the results did not support the previous findings reported with use of ATDs. Hence, our study highlights the benefits of using PMHS for validating the accuracy of iMGs since they closely mimic the human body compared to any ATD's mandible.