Study protocol: Optimising patient positioning for the planning of accelerated partial breast radiotherapy for the integrated magnetic resonance linear accelerator: OPRAH MRL.

BACKGROUND: Accelerated partial breast irradiation (APBI) is an accepted treatment option for early breast cancer. Treatment delivered on the Magnetic Resonance integrated Linear Accelerator (MRL) provides the added assurance of improved soft tissue visibility, important in the delivery of APBI. This technique can be delivered in both the supine and prone positions, however current literature suggests that prone treatment on the MRL is infeasible due to physical limitations with bore size. This study aims to investigate the feasibility of positioning patients on a custom designed prone breast board compared with supine positioning on a personalised vacuum bag. Geometric distortion, the relative position of Organs at Risk (OAR) to the tumour bed and breathing motion (intrafraction motion) will be compared between the supine and prone positions. The study will also investigate the positional impact on dosimetry, patient experience, and position preference. METHODS: Up to 30 patients will be recruited over a 12-month period for participation in this Human Research Ethics Committee approved exploratory cohort study. Patients will be scanned on the magnetic resonance imaging (MRI) Simulator in both the supine and prone positions as per current standard of care for APBI simulation. Supine and prone positioning comparisons will all be assessed on de-identified MRI image pairs, acquired using appropriate software. Patient experience will be explored through completion of a short, anonymous electronic survey. Descriptive statistics will be used for reporting of results with categorical, parametric/non-parametric tests applied (data format dependent). Survey results will be interpreted by comparison of percentage frequencies across the Likert scales. Thematic content analysis will be used to interpret qualitative data from the open-ended survey questions. DISCUSSION: The results of this study will be used to assess the feasibility of treating patients with APBI in the prone position on a custom designed board on the MRL. It may also be used to assist with identification of patients who would benefit from this position over supine without the need to perform both scans. Patient experience and technical considerations will be utilised to develop a tool to assist in this process. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN1262400067583. Registered 28th of May 2024. https://www.anzctr.org.au/ACTRN12624000679583.aspx.

StrataXRT for the prevention of acute radiation dermatitis in breast cancer: a pilot study.

PURPOSE: Previous literature has produced heterogeneous results on StrataXRT for prevention of acute radiation dermatitis (RD) in breast cancer. This pilot study aimed to assess the feasibility and efficacy of StrataXRT in a cancer center. METHODS: The study consisted of five cohorts: (1) patients with large breasts treated with local radiation therapy (RT) either in the supine position or (2) the prone position, (3) patients receiving locoregional breast RT with any breast size, and (4) patients receiving chest wall RT, either locally or (5) locoregionally. The primary endpoint of the study was RD grade as assessed using the Common Terminology Criteria for Adverse Events. Secondary endpoints included incidence of moist desquamation (MD), patient- and clinician-reported skin assessments, patient quality of life as assessed by the Skindex-16, and patient satisfaction. These outcomes were compared with those from a published trial from the same institution assessing standard of care and Mepitel Film (MF) as prevention of breast RD. RESULTS: Forty-five patients receiving RT to the breast or chest wall were enrolled. Two withdrew, leaving 43 evaluable patients. Overall, two (4.7%) patients had grade 3 RD, 14 (32.6%) had grade 2 RD, and 27 (62.8%) had grade 1 RD. Ten patients (23.3%) developed MD during/after RT. CONCLUSION: StrataXRT is effective in preventing grade 3 RD in patients, and the most promising results were observed within the prone cohort. Further research includes evaluating the efficacy of StrataXRT against the standard of care for the prophylaxis of RD. TRIAL REGISTRATION: The study protocol was registered at ClinicalTrials.gov (identifier: NCT05594498) on October 13, 2022.

Analyzing learning curve for supine percutaneous nephrolithotomy in urology resident training programme: comparative analysis.

INTRODUCTION: This article attempts to provide a comprehensive review of the learning objectives and importance of the supine percutaneous nephrolithotomy (PCNL) technique. MATERIAL METHOD: We retrospectively reviewed the cases of Supine PCNL between January 2018 and January 2024. We divided the groups into 3: residents between 2 and 3 years (Group 1), residents between 4 and 5 years (Group 2), and endourologist (Group 3). The 2-3-year resident started to perform PCNL for the first time, while the 4-5-year resident started to perform Supine PCNL for the first time while previously performing prone PCNL. RESULTS: Access, fluoroscopy, and operation time were higher in Group 1, shorter in Group 2, and shortest in Group 3 (p < 0.001). Postoperative length of stay and the need for additional treatment were found to be shorter (p < 0.001), and the stone-free rate (SFR) increased (p < 0.001) from Group 1 to Group 3. The highest complication rates were observed in Group 1 (p = 0.002). SFR rate increased as the number of cases increased in Group 1 patients. Success was stable after 46-60 cases in terms of SFR. In Group 2, the SFR rate was stable after 31-45. CASES: The most complications were observed in Group 1 and the least in Group 3. CONCLUSION: In 2-3-year residents, access time and fluoroscopy time decrease with experience. In 4-5-year residents, due to their expertise in prone PCNL, the operation time and fluoroscopy time decrease with the number of cases performed. SFR is higher after 46-60 cases for 2-3-year residents and 31-45 cases for 4-5-year residents.

Differences in lung attenuation gradients between supine and standing positions in healthy participants on conventional/supine and upright computed tomography.

The effect of gravity on the lungs has been evaluated using computed tomography (CT) in the supine and prone positions but not the standing position. However, as humans spend most of the daytime in the standing position, we aimed to compare lung attenuation gradients between the supine and standing positions, and to assess the correlations between the lung attenuation gradients and participant characteristics, including pulmonary function test results. Overall, 100 healthy participants underwent conventional/supine and upright CT, and lung attenuation gradients were measured. Lung attenuation gradients in anteroposterior direction were greater in the supine position than in standing position (all p values < 0.0001) in both upper lobes at the level of the aortic arch (right: standing/supine, -0.02 ± 0.19/0.53 ± 0.21; left: standing/supine, -0.06 ± 0.20/0.51 ± 0.21); in the right middle (standing/supine, -0.26 ± 0.41/0.53 ± 0.39), left upper (standing/supine, -0.35 ± 0.50/0.66 ± 0.54), and lower lobes at the level of the inferior pulmonary vein (right: standing/supine, -0.22 ± 0.30/0.65 ± 0.41; left: standing/supine, -0.16 ± 0.25/0.73 ± 0.54); and in both lower lobes just above the diaphragm (right: standing/supine, -0.13 ± 0.22/0.52 ± 0.32; left: standing/supine, -0.30 ± 0.57/0.55 ± 0.37). Craniocaudal gradients were greater in the standing position (right: standing/supine, 0.41 ± 0.30/0.00 ± 0.16; left: standing/supine, 0.35 ± 0.30/-0.02 ± 0.16, all p values < 0.0001). No moderate to very high correlations were observed between age, sex, height, weight, body index mass, or pulmonary function test results and each lung attenuation gradient. Lung attenuation gradients in anteroposterior direction, which was observed in the supine position, disappeared in the standing position. However, the craniocaudal lung attenuation gradient, which was not present in the supine position, appeared in the standing position.

Effects of sitting, supine, and prone postures on nasal patency in individuals with obstructive sleep apnea syndrome.

BACKGROUND: Studies have found that in healthy individuals without nasal disease, changes in posture cause an increase in nasal resistance, especially in the prone posture. Many patients with obstructive sleep apnea syndrome (OSAS) sleep in a prone posture, but no studies have examined the effect of this change in posture on nasal resistance in patients with OSAS. Therefore, we conducted this study to investigate this posture-related physical phenomenon in individuals with OSAS. METHODS: We evaluated the nasal patency of 29 patients diagnosed with OSAS using the visual analog scale (VAS), acoustic rhinometry, and video-endoscopy in the sitting, supine, and prone postures. RESULTS: In the OSAS group, both supine and prone postures significantly influenced subjective nasal blockage and led to a notable reduction in the minimal cross-sectional area (mCSA) as determined by acoustic rhinometry, compared to the sitting posture. The prone posture exhibited a more pronounced effect than the supine posture. Endoscopic evaluations further revealed increased hypertrophy of the inferior turbinate in the supine posture for the right nasal passage and the prone posture for the left. However, no significant differences were observed between the prone and supine postures. CONCLUSION: In OSAS patients, nasal resistance significantly increased in supine and prone postures compared to sitting, with the prone posture showing a greater effect. Clinicians should consider a patient's habitual sleep posture and the effects of postural changes when assessing OSAS severity and devising treatment plans.

Lightweight Neural Network for Sleep Posture Classification Using Pressure Sensing Mat at Various Sensor Densities.

Recently, pressure-sensing mats have been widely used to capture static and dynamic pressure over sleep for posture recognition. Both a full-size mat with a low-density sensing array for figuring out the structure of the whole body and a miniature scale mat with a high-density sensing array for identifying the local characteristics around the chest have been investigated. However, both of the mat systems may face the challenge in the trade-off between the computational complexity (involving the size, density, etc. of the mat) and the performance of sleep posture recognition, where high performance may requires overcomplex computation and result in time latency in real-time sleep posture monitoring. In this paper, a lightweight neural network named ConcatNet, is proposed to realize sleep postures (supine, left, right, and prone) recognition in real time while maintaining a favorable performance. In ConcatNet, the inception module is proposed to extract the image features under multiple receptive fields, while the multi-layer feature fusion module is utilized to fuse deep and shallow features to enhance the model performance. To further improve the efficiency of the model, the depthwise convolution is adopoted. ConcatNet models in 3 different scales (ConcatNet-S, ConcatNet-M, and ConcatNet-L) are built to explore the impact of the sensor density on sleep posture recognition performance. Experimental results exhibit that ConcatNet-M corresponding to medium sensor density ( 16×16 ) achieved the best comprehensive performance, with short-term data cross-validation accuracy at 95.56% and overnight data testing accuracy at 94.68%. The model size is 7.91KB, FLOPs is 56.47K, and the inference time is only 0.38ms, which shows an outstanding performance of real-time sleep posture recognition with minimum consumption, indicating the potential to be deployed in mobile devices.

Which Position for Novice Surgeons? Effect of Supine and Prone Positions on Percutaneous Nephrolithotomy Learning Curve.

Background and Objectives: Percutaneous nephrolithotomy (PCNL) is a current treatment method with high success rates and low complication rates in treating large kidney stones. It can be conducted in different positions, especially supine and prone positions. PCNL in the supine position is becoming increasingly common due to its advantages, such as simultaneous retrograde intervention and better anesthesia management. This study aimed to assess how the choice of position impacts the PCNL learning curve. Materials and Methods: The results of the first 50 consecutive PCNL cases performed by two separate chief residents as primary surgeons in supine and prone positions in a reference center for stone treatment between August 2021 and January 2023 were evaluated. The two groups' demographic and clinical data, stone-free rates, operation times, and fluoroscopy times were compared. Results: While the mean operation time was 94.6 ± 9.8 min in the supine PCNL group, it was 129.9 ± 20.3 min in the prone PCNL group (p < 0.001). Median fluoroscopy times in the supine PCNL and prone PCNL groups were 31 (10-89) seconds and 48 (23-156) seconds, respectively (p = 0.001). During the operation, the plateau was reached after the 10th case in the supine PCNL group, while it was reached after the 40th case in the prone PCNL group. Conclusions: For surgeons who are novices in performing PCNL, supine PCNL may offer both better results and a faster learning curve. Prospective and randomized studies can provide more robust conclusions on this subject.

Relationship between sleep position and otitis media in infants: The Japan environment and children's study.

OBJECTIVE: Otitis media is a disease that commonly occurs in infants. Various risk factors have been reported. Sleep position has been reported to be associated with various diseases. There is no report on the relationship between otitis media and sleep position. We examined the incidence of otitis media and sleep position in infants. METHODS: We used data from the Japan Environment Children's Study. We used multivariate logistic analysis to examine the relationship between sleep position and the incidence of otitis media in infants aged up to 6 months. In addition, we conducted a stratified analysis based on whether the child was able to turn over in bed at 6 months of age. RESULTS: The study population comprised 85,731 participants. The incidence of otitis media by sleep position was significantly higher when the infant was in the prone position compared to any other position (adjusted odds ratio, 1.206; 95 %CI, 1.038-1.401). Stratified analysis of turning showed that otitis media was more common in the prone position in all groups. CONCLUSION: In the current study, infants aged 6 months or younger who slept in the prone position were more likely to have otitis media. Sleep position interview and guidance on changing sleep position may be useful for the prevention of otitis media.

The atlas of supine single port extraperitoneal access.

INTRODUCTION: The introduction of Single-Port (SP) platform opened the field to new surgical options, allowing to perform major urological robot-assisted procedures extraperitoneally and with a supine patient positioning (1-3). Nevertheless, a comprehensive description of different supine access options is still lacking (4-6). In this light, we provided a step-by-step guide of SP extraperitoneal supine access options also exploring preliminary surgical outcomes. MATERIALS AND METHODS: Transvesical access was performed by a transversal incision 3cm above the pubic bone, after the anterior abdominal sheet incision, the bladder was insufflated with a flexible cystoscope and the detrusor muscle was incised at the level of the bladder dome. Similarly, the extraperitoneal access was carried out with a 4cm incision above the pubic bone, once visualized the preperitoneal space the prevesical fat was gently spread. The Low Anterior Access was performed with a 3cm incision at the McBurney point, the abdominal muscles were then spread. A gentle dissection was used laterally to develop the retroperitoneal space. RESULTS: Overall, sixteen different procedures were performed with supine extraperitoneal access on 623 consecutive patients. No intraoperative conversions occurred. The median access time was 16 (IQR 12-21), 11 (IQR 7-14) and 14 (IQR 10-18) minutes in case of transvesical, extraperitoneal and low anterior access, respectively. Notably, 81.5 % of patients were discharged on the same day with a postoperative opioid free rate of 73%. CONCLUSION: The Atlas provides a comprehensive step-by-step guide to successfully perform all major urological SP procedures extraperitoneally and with supine patient positioning.

How to Best Identify Acetabular Retroversion on Radiographs: Thresholds to Guide Clinical Practice.

BACKGROUND: Acetabular retroversion is associated with impingement and instability. An adequate interpretation of acetabular version and coverage on radiographs is essential to determine the optimal treatment strategy (periacetabular osteotomy vs hip arthroscopic surgery). The crossover sign (COS) has been associated with the presence of acetabular retroversion, and the anterior wall index (AWI) and posterior wall index (PWI) assess anteroposterior acetabular coverage. However, the radiographic appearance of the acetabulum is sensitive to anterior inferior iliac spine (AIIS) morphology and pelvic tilt (PT), which differs between the supine and standing positions. PURPOSE: To (1) identify differences in the acetabular appearance between the supine and standing positions among patients presenting with hip pain; (2) determine factors (acetabular version, AIIS morphology, and spinopelvic characteristics) associated with the crossover ratio (COR), AWI, and PWI; and (3) define relevant clinical thresholds to guide management. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients who presented to a hip preservation surgical unit (n = 134) were included (mean age, 35 ± 8 years; 58% female; mean body mass index, 27 ± 6). All participants underwent supine and standing anteroposterior pelvic radiography to assess the COS, COR, AWI, and PWI as well as standing lateral radiography to determine standing PT. Computed tomography was used to measure supine PT, acetabular version, and AIIS morphology. Acetabular version was measured at 3 transverse levels, corresponding to the 1-, 2-, and 3-o'clock positions. The correlation between radiographic characteristics (COR, AWI, and PWI) and acetabular version, AIIS morphology, and PT was calculated using the Spearman correlation coefficient. Receiver operating characteristic curve analysis was performed to define thresholds for the COR, AWI, and PWI to identify retroversion (version thresholds: <10°, <5°, and <0°). RESULTS: The COS was present in 55% of hips when supine and 30% when standing, with a mean difference in the COR of 12%. The supine COR (rho = -0.661) and AWI/PWI ratio (rho = -0.618) strongly correlated with acetabular version. The COS was more prevalent among patients with type 2 AIIS morphology (71%) than among those with type 1 AIIS morphology (43%) (P = .003). COR thresholds of 23% and 28% were able to identify acetabular version <5° (sensitivity = 81%; specificity = 80%) and <0° (sensitivity = 88%; specificity = 85%), respectively. An AWI/PWI ratio >0.6 was able to reliably identify acetabular version <0° (sensitivity = 83%; specificity = 84%). In the presence of a COR >30% and an AWI/PWI ratio >0.6, the specificity to detect retroversion was significantly increased (>90%). CONCLUSIONS: The presence of the COS was very common among patients with hip pain. False-positive results (high COR/normal version) may occur because of AIIS morphology/low PT. Relevant thresholds of COR >30% and AWI/PWI ratio >0.6 can help with diagnostic accuracy. In cases in which either the COR or AWI/PWI ratio is high, axial cross-sectional imaging can further help to avoid false-positive results.

Clinical comparison of lateral supine position mini-percutaneous nephrolithotomy and anatrophic nephrolithotomy in the treatment of complete staghorn renal calculi.

BACKGROUND: At present, the guidelines for urology recommend percutaneous nephrolithotomy (PCNL) as the preferred treatment for staghorn renal calculi (SRC). However, for complete SRC, it has been questioned by clinicians and patients due to high residual stone rate, complications, repeated hospitalizations and high treatment cost. Anatrophic nephrolithotomy (ANL) is a traditional and classic method for the treatment of SRC. Due to its high trauma and high technical requirements, it is difficult to carry out in primary hospitals, and gradually replaced by PCNL. The purpose of this study is to compare the efficacy of PCNL and ANL in the treatment of complete SRC. METHODS: Overall, 238 patients with complete SRC were divided into mini-PCNL in lateral supine position group, (n = 190) and ANL group (n = 94) according to treatment for a retrospective cohort study. The calculi parameters, renal function index, comorbidities of calculi, surgical complications, length and frequency of hospitalization, treatment costs, results of postoperative satisfaction survey were compared between the two groups. RESULTS: The risk of the residual stone rate after mini-PCNL in lateral supine position was 239 times (OR = 238.667, P < 0.0001), the number of residual stone 1.3 times (OR = 1.326, P < 0.0001), the amount of residual stone 2.2 times (OR = 2.224, P < 0.0001) that of ANL. The risk of the cost of initial treatment after mini-PCNL in lateral supine position was 3.3 times (OR = 3.273, P < 0.0001), the total cost of treatment 4 times (OR = 4.051, P < 0.0001), the total length of hospital stays 1.4 times (OR = 1.44, P < 0.0001) that of ANL, the incidence of postoperative renal atrophy was 2.2 times (OR = 2.171, P = 0.008) higher in the ANL than in the mini-PCNL in lateral supine position. Glomerular filtration rate (GFR) reduction after ANL was 1.4 times (OR = 1.381, P = 0.037) greater than that after mini-PCNL in lateral supine position at 24-month follow-up. The risk of the overall satisfaction of ANL was 58 times (OR = 57.857, P < 0.0001) higher than that of mini-PCNL in lateral supine position, the number of branches of staghorn greater than 8 is a high risk factor for the occurrence of residual stone after mini-PCNL in lateral supine position (OR = 353.137, P < 0.0001). CONCLUSION: Although the risk of renal atrophy and decreased GFR after ANL is higher than that of mini-PCNL in lateral supine position, the efficacy of traditional ANL in the treatment of complete SRC was generally superior to that of mini-PCNL in lateral supine position. Moreover, number of branches of staghorn greater than 8 are the preferred ANL for complete SRC. TRIAL REGISTRATION: ChiCTR2100047462. The trial was registered in the Chinese Clinical Trial Registry; registration date: 19/06/2021.

Assessment of arthrogenic quadriceps muscle inhibition by physical examination in the supine position during isometric contraction is feasible as demonstrated by electromyography: a cross-sectional study.

BACKGROUND: Preventing severe arthrogenic muscle inhibition (AMI) after knee injury is critical for better prognosis. The novel Sonnery-Cottet classification of AMI enables the evaluation of AMI severity but requires validation. This study aimed to investigate the electromyography (EMG) patterns of leg muscles in the examination position from the classification during isometric contraction to confirm its validity. We hypothesised that the AMI pattern, which is characterised by quadriceps inhibition and hamstring hypercontraction, would be detectable in the supine position during isometric contraction. METHODS: Patients with meniscal or knee ligament injuries were enrolled between August 2023 and May 2024. Surface EMG was assessed during submaximal voluntary isometric contractions (sMVIC) at 0° extension in the supine position for the vastus medialis (VM) and vastus lateralis (VL) muscles and at 20° flexion in the prone position for the semitendinosus (ST) and biceps femoris (BF) muscles. Reference values for normalisation were obtained from the EMG activity during the gait of the uninjured leg. The Kruskal-Wallis test was used to compare the activation patterns of the muscle groups within the same leg, and the post-hoc tests were conducted using the Mann-Whitney U test and Bonferroni correction. RESULTS: Electromyographic data of 40 patients with knee injuries were analyzed. During sMVIC, the extensor and flexor muscles of the injured leg showed distinct behaviours (P < 0.001), whereas the uninjured side did not (P = 0.144). In the injured leg, the VM differed significantly from the ST (P = 0.018), and the VL differed significantly from the ST and BF (P = 0.001 and P = 0.026, respectively). However, there were no statistically significant differences within the extensor muscle groups (VM and VL, P = 0.487) or flexor muscle groups (ST and BF, P = 0.377). CONCLUSION: AMI was detectable in the examination position suggested by the Sonnery-Cottet classification. The flexor and extensor muscles of the injured leg exhibited distinct activation behaviours, with inhibition predominantly occurring in the quadriceps muscles, whereas the hamstrings showed excitation.

Changes in blood gas in supine and prone positions in percutaneous stone surgery: does position have any advantage for hemodynamics?

To evaluate whether different positions are advantageous for hemodynamics and respiratory balance in patients undergoing percutaneous nephrolithotomy (PCNL) procedures. Pre- and postoperative arterial blood gas data obtained during spontaneous breathing for 67 prone (Group 1) and 56 supine (Group 2) patients undergoing PCNL were analyzed. Additionally data on all patients' gender, age, body mass index, stone size, access and surgical duration, volume of irrigation fluid, length of hospital stay, requirement for blood transfusion, and residual stones were recorded: There were no differences between the groups in terms of age, stone size, operation time, access time, radiation exposure, transfusion requirements, stone-free rate, and length of hospitalization. A statistically significant pH decrease was observed in both groups in the postoperative period (p = 0.001 and p = 0.001, respectively). There was a statistically significant increase in pCO2 values in both groups in the postoperative period (p = 0.001 and p = 0.024, respectively), and that increase did not differ significantly between the groups (p = 0.624). A statistically significant decrease in pO2 and SpO2 values was observed in both groups in the postoperative period compared to the preoperative period. Again, no statistical difference was observed between the groups for these values. There was a statistically significant decrease in bicarbonate in both groups period (p < 0.001 and p = 0.001, respectively). Hemodynamics and the respiratory balance of the patient are impaired in both prone and supine positions. Neither position is superior to the other in this respect.

Change in cup orientation from supine to standing posture: a prospective cohort study of 419 total hip arthroplasties.

BACKGROUND AND PURPOSE: Arthroplasty surgeons traditionally assess cup orientation after total hip arthroplasty (THA) on supine radiographs. Contemporary hip-spine analyses provide information on standing, functional cup orientation. This study aims to (i) characterize cup orientations when supine and standing; (ii) determine orientation differences between postures; and (iii) identify factors associated with magnitude of orientation differences. METHODS: This is a 2-center, multi-surgeon, prospective, consecutive cohort study. 419 primary THAs were included (57% women; mean age: 64 years, standard deviation [SD] 11). All patients underwent supine and standing antero-posterior pelvic and lateral spinopelvic radiographs. Cup orientation and spinopelvic parameters were measured. Target cup orientation was defined as inclination/anteversion of 40°/20° ± 10°. A change in orientation (Δinclination/Δanteversion) between postures > 5° was defined as clinically significant. Variability was defined as 2 x SD. RESULTS: Inclination increased from 40° (supine) to 42° (standing) corresponding to a Δinclination of 2° (95% confidence interval [CI] 2-3). Anteversion increased from 25° (supine) to 30° (standing) corresponding to a Δanteversion of 5° (CI 5-6). When supine, 69% (CI 65-74) of THAs were within target, but only 44% (CI 39-49) were within target when standing, resulting in a further 26% (CI 21-30) being out of target when standing. From supine to standing, a clinically significant change in anteversion (> 5°) was seen in 47% (CI 42-52) of cases. Δanteversion was higher in women than in men (6°, CI 5-7 vs 5°, CI 4-5) corresponding to a difference of 1° (CI 1-2), which was dependent on tilt change, standing cup anteversion, age, and standing pelvic tilt. CONCLUSION: Cup inclination and version increase upon standing but significant variability exists due to patient factors.

Automated software-derived supine baseline impedance is highly correlated with manual nocturnal baseline impedance for the diagnosis of GERD.

BACKGROUND: Mean nocturnal baseline impedance (MNBI) can improve diagnostic accuracy for gastroesophageal reflux disease (GERD), but must be manually calculated and is not routinely reported. We aimed to determine how automated software-derived mean supine baseline impedance (MSBI), a potential novel GERD metric, is related to MNBI. METHODS: Consecutively obtained pH-impedance studies were assessed. Manually extracted MNBI was compared to MSBI using paired t-test and Spearman's correlations. KEY RESULTS: The correlation between MNBI and MSBI was very high (ρ = 0.966, p < 0.01). CONCLUSIONS & INFERENCES: The ease of acquisition and correlation with MNBI warrant the routine clinical use and reporting of MSBI with pH-impedance studies.

How Does Radiographic Acetabular Morphology Change Between the Supine and Standing Positions in Asymptomatic Volunteers?

BACKGROUND: The radiographic appearance of the acetabulum differs between the supine and standing positions in patients with hip conditions. The pelvis undergoes a change in tilt when transitioning between positions, resulting in variations in version and acetabular coverage. However, the extent of these variations in well-functioning volunteers without compensatory patterns caused by pain is unknown. QUESTIONS/PURPOSES: We performed this study to (1) quantify differences in radiographic acetabular measurements when transitioning between supine and standing among asymptomatic, well-functioning volunteers; (2) assess differences in pelvic tilt between positions; and (3) test whether individual anatomic parameters are associated with the change in tilt. METHODS: This was a prospective, single-center study performed at an academic referral center. One hundred volunteers (students, staff, and patients with upper limb injuries) with well-functioning hips (Oxford hip score ≥ 45) were invited to participate. A total of 45% (45) of them were female, their mean age was 37 ± 14 years, and their mean BMI was 25 ± 2 kg/m 2 . Supine and standing AP pelvic radiographs were analyzed to determine numerous acetabular parameters including the lateral center-edge angle (LCEA), acetabular index (AI), anterior wall index (AWI), posterior wall index (PWI), crossover sign (COS), crossover ratio (COR), posterior wall sign (PWS), ischial spine sign (ISS), and femoroepiphyseal acetabular roof index (FEAR), as well as pelvic parameters including the sacrofemoral-pubic angle (SFP). Spinopelvic parameters were measured from lateral standing spinopelvic radiographs. Radiographic measurements were performed by one hip preservation research fellow and a fellowship-trained staff surgeon. Differences in parameters were determined, and correlations between postural differences and morphological parameters were tested. Clinically important differences were defined as a difference greater than 3° for acetabular angle measurements and 0.03 for acetabular ratio measurements, based on previous studies. RESULTS: Lateral coverage angles did not show a clinically important difference between positions. AWI decreased when standing (0.47 ± 0.13 versus 0.41 ± 0.14; p < 0.001), whereas acetabular retroversion signs were more pronounced when supine (COS: 34% [34 of 100], PWS: 68% [68 of 100], and ISS: 34% [34 of 100] versus COS: 19% [19 of 100], PWS: 38% [38 of 100], and ISS: 14% [14 of 100]; all p values < 0.05). Pelvic tilt increased by a mean of 4° ± 4° when standing, but the range of change was from -15° to 7°. The change in AWI (ρ = 0.47; p < 0.001), PWI (ρ = -0.45; p < 0.001), and COR (ρ = 0.52; p < 0.001) between positions correlated with ΔSFP. Volunteers with spinal imbalance (pelvic incidence lumbar lordosis > 10°) demonstrated greater change in pelvic tilt (ΔSFP) (-7° ± 3° versus -4° ± 4°; p = 0.02) and a greater reduction in AWI (by 10%). These volunteers demonstrated reduced standing lumbar lordosis angles (45° ± 11° versus 61° ± 10°; p = 0.001). CONCLUSION: Acetabular version increases from supine to standing because of an increase in pelvic tilt. The change in pelvic tilt between positions exhibited substantial variability. Individuals with reduced lumbar lordosis for a given pelvic incidence value demonstrated greater pelvic mobility. No features on supine radiographs were associated with the change in tilt. CLINICAL RELEVANCE: Performing standing radiographs in addition to supine views can help identify aberrant physiologic patterns in patients with diagnostic dilemmas and might thus help with management. Normative data of pelvic tilt change can help clinicians identify patients who demonstrate excessive change in tilt that contributes to abnormal hip pathomechanics.

Ankle impingement after extra-articular open fracture of the leg: Full arthroscopic treatment in the supine position.

OBJECTIVE: Extra-articular open fractures of the leg often result from high energy trauma. After healing, a painful ankle impingement may occur. In the event of anterior and posterior impingements, arthroscopic treatment may require two surgical positions. We propose an operative strategy to treat anterior and posterior ankle impingement after extra-articular open fracture of the leg. Our hypothesis is that this strategy is simple, effective and with a low risk of complication. MATERIAL AND METHOD: Anterior ankle impingements were treated by anterior arthroscopy in supine position; anterior and posterior impingements were treated by anterior and posterior arthroscopy in supine position; anterior and posterior impingements associated with retraction of gastrocnemius muscles were treated with anterior arthroscopy in supine position followed by posterior arthroscopy in prone position, and an open tendon lengthening of the calcaneal tendon in the same position. The anterior and posterior arthroscopic release was tested in the cadaver laboratory. Then, the surgical strategy was applied to our patients in our clinical practice. After, we analysed retrospectively the results of the strategy in the first patients treated for a painful ankle impingement after extra-articular open fracture of the leg. The data retrieved were the importance of pain (VAS), the presence of clinical instability, ankle mobility, gastrocnemius retraction and the AOFAS functional score and the post-operative complications. Then, these data were compared before the surgery and at last follow-up. RESULTS: From the cadaver laboratory, anterior and posterior arthroscopic release was possible in all cases without changing position. From our clinical practice, we included 5 patients (3 women and 2 men, mean age 43 years) suffering from an ankle impingement after extra-articular open fracture of the leg (2 patients with isolated anterior impingement, 1 patient with anterior and posterior impingement, and 2 patients with anterior and posterior impingement plus a gastrocnemius retraction). All post-operative parameters (pain, range of motion and AOFAS score) at mean follow-up of 53 months were improved. No post-operative complication was reported. CONCLUSION: We propose a surgical strategy adapted to the different clinical presentations of ankle impingement after extra-articular open fracture of the leg.

Perfection is the enemy of good. A Letter to the Editor on "Orthostatic hypotension in Parkinson's disease: Sit-to-stand vs. supine-to-stand protocol and clinical correlates".

Orthostatic hypotension (OH) is prevalent in Parkinson's disease. Lim et al. report a higher OH detection rate with the supine-to-stand test compared to the sit-to-stand test. While they favour the supine-to-stand test, we argue that the sit-to-stand test, with adjusted blood pressure thresholds, remains a valuable and practical screening tool.

Effect of the prone position on mechanical power in elective surgical patients under general anesthesia: A prospective observational study.

OBJECTIVES: To evaluate how the prone position influences mechanical power (MP) during elective surgical procedures. METHODS: In this prospective study carried out at Karadeniz Eregli Government Hospital, Zonguldak, Turkey, from January 2024 to February 2024, 76 patients under general anesthesia were evaluated at different time points during the surgical procedure. Hemodynamic, laboratory, and mechanical ventilation data were also recorded. RESULTS: The MP increased in the prone position at the beginning of surgery. Transitioning to the supine position at the end of surgery led to a decrease in MP. At the end of surgery, the mean MP in supine and prone positions was found to be higher compared to those measured in the first hour of surgery. Mechanical power and body mass index (BMI) exhibited a significant positive correlation. CONCLUSION: Position changes influence MP. Returning to the prone position increases MP. An increase in BMI is associated with an increase in MP.ANZCTR Reg. No.: ACTRN12623001281684.

Ultrasound quantification of pleural effusion volume in supine position: comparison of three model formulae.

BACKGROUND: To investigate the accuracy of three model formulae for ultrasound quantification of pleural effusion (PE) volume in patients in supine position. METHODS: A prospective study including 100 patients with thoracentesis and drainage of PE was conducted. Three model formulae (single section model, two section model and multi-section model) were used to calculate the PE volume. The correlation and consistency analyses between calculated volumes derived from three models and actual PE volume were performed. RESULTS: PE volumes calculated by three models all showed significant linear correlations with actual PE volume in supine position (all p < 0.001). The reliability of multi-section model in predicting PE volume was significantly higher than that of single section model and slightly higher than that of two section model. When compared with actual drainage volume, the intra-class correlation coefficients (ICCs) of single section model, two section model and multi-section model were 0.72, 0.97 and 0.99, respectively. Significant consistency between calculated PE volumes by using two section model and multi-section model existed for full PE volume range (ICC 0.98). CONCLUSION: Based on the convenience and accuracy of ultrasound quantification of PE volume, two section model is recommended for pleural effusion assessment in routine clinic, though different model formulae can be selected according to clinical needs.