Utility of dual energy computed tomography in the evaluation of infiltrative skeletal lesions and metastasis: a literature review.

Computed tomography (CT) is routinely used to diagnose and evaluate metastatic lesions in oncology. CT alone suffers from lack of sensitivity, especially for skeletal lesions in the bone marrow and lesions that have similar attenuation profiles to surrounding bone. Magnetic resonance imaging and nuclear medicine imaging remain the gold standard in evaluating skeletal lesions. However, compared to CT, these modalities are not as widely available or suitable for all patients. Dual energy computed tomography (DECT) exploits variations in linear attenuation coefficient of materials at different photon energy levels to reconstruct images based on material composition. DECT in musculoskeletal imaging is used in the imaging of crystal arthropathy and detecting subtle fractures, but it is not broadly utilized in evaluating infiltrative skeletal lesions. Malignant skeletal lesions have different tissue and molecular compositions compared to normal bone. DECT may exploit these physical differences to delineate infiltrative skeletal lesions from surrounding bone better than conventional monoenergetic CT. Studies so far have examined the utility of DECT in evaluating skeletal metastases, multiple myeloma lesions, pathologic fractures, and performing image-guided biopsies with promising results. These studies were mostly retrospective analyses and case reports containing small samples sizes. As DECT becomes more widely used clinically and more scientific studies evaluating the performance of DECT are published, DECT may eventually become an important modality in the work-up of infiltrative skeletal lesions. It may even challenge MRI and nuclear medicine because of relatively faster scanning times and ease of access.

Investigating the nasal cycle using unilateral peak nasal inspiratory flow and acoustic rhinometry minimal cross-sectional area measurements.

OBJECTIVE: To plot the nasal cycle using unilateral peak nasal inspiratory flow (UPNIF) and unilateral minimal cross-sectional area (UMCA) readings demonstrating a linear relationship in normal nasal function. Additionally, to determine how this changes in abnormal nasal function. DESIGN: A cross-sectional study measuring UPNIF and UMCA in controls demonstrating normal nasal function and in patients with nasal obstruction. SETTING: Royal National Throat Nose and Ear Hospital, London. PARTICIPANTS: A total of 39 participants, 26 controls and 13 patients, were recruited. Controls exhibited normal nasal function with SNOT-22 <5. Patients nasal obstruction symptoms secondary to inflammation or structural abnormality with SNOT-22 >9. MAIN OUTCOME MEASURES AND RESULTS: Airflow rates and resistance values were derived from UPNIF and UMCA measurements respectively based on Poiseuille's laws. Ratios between right and left UPNIF and UMCA values were taken to adjust for confounding factors. The relationship of 1/Resistance Ratio and Airflow Rate Ratio demonstrated a linear of direct proportionality of strong correlation and statistical significance (correlation coefficient = 0.76, P « 0.01). This suggests that data points from controls with a normal nasal cycle lie closely along the regressed line, whilst those lying significantly away were shown to belong to patients with nasal dysfunction. Olfactory dysfunction appears to be a sensitive discriminator in predicting this. CONCLUSION: This study demonstrates the directly proportional relationship of 1/Resistance Ratio and Airflow Rate Ratio in normal nasal function. Furthermore, nasal pathology can be predicted if data points lie significantly outside these normal limits. Further studies are needed to validate exact normal and abnormal thresholds.

Preventing brachial plexus injury during shoulder surgery: a real-time cadaveric study.

BACKGROUND: Brachial plexopathy is not uncommon after shoulder surgery. Although thought to be due to stretch neuropathy, its etiology is poorly understood. This study aimed to identify arm positions and maneuvers that may risk causing brachial plexopathy during shoulder arthroplasty. METHODS: Tensions in the cords of the brachial plexuses of 6 human cadaveric upper limbs were measured using load cells while each limb was placed in different arm positions and while they underwent shoulder hemiarthroplasty and revision reverse arthroplasty. Arthroplasty procedures in 4 specimens were performed with standard limb positioning (unsupported), and 2 specimens were supported from under the elbow (supported). Each cord then underwent biomechanical testing to identify tension corresponding to 10% strain (the stretch neuropathy threshold in animal models). RESULTS: Tensions exceeding 15 N, 11 N, and 9 N in the lateral, medial, and posterior cords, respectively, produced 10% strain. Shoulder abduction >70° and combined external rotation >60° with extension >50° increased medial cord tension above the 10% strain threshold. Medial cord tensions (mean ± standard error of the mean) in unsupported specimens increased over baseline during hemiarthroplasty (sounder insertion [4.7 ± 0.6 N, P = .04], prosthesis impaction [6.1 ± 0.8 N, P = .04], and arthroplasty reduction [5.0 ± 0.7 N, P = .04]) and revision reverse arthroplasty (retractor positioning [7.2 ± 0.8 N, P = .02]). Supported specimens experienced lower tensions than unsupported specimens. CONCLUSIONS: Shoulder abduction >70°, combined external rotation >60° with extension >50°, and downward forces on the humeral shaft may risk causing brachial plexopathy. Retractor placement, sounder insertion, humeral prosthesis impaction, and arthroplasty reduction increase medial cord tensions during shoulder arthroplasty. Supporting the arm from under the elbow protected the brachial plexus in this cadaveric model.

Trauma versus no trauma: an analysis of the effect of tear mechanism on tendon healing in 1300 consecutive patients after arthroscopic rotator cuff repair.

BACKGROUND: Patients with rotator cuff tears often recall a specific initiating event (traumatic), whereas many cannot (nontraumatic). It is unclear how important a history of trauma is to the outcomes of rotator cuff repair. METHODS: This question was addressed in a study cohort of 1300 consecutive patients who completed a preoperative questionnaire regarding their shoulder injury and had a systematic evaluation of shoulder range of motion and strength, a primary arthroscopic rotator cuff repair performed by a single surgeon, an ultrasound scan, and the same subjective and objective measurements made of their shoulder 6 months after surgery. Post hoc, this cohort was separated into 2 groups: those who reported no history of trauma on presentation (n = 489) and those with a history of traumatic injury (n = 811). RESULTS: The retear rate in the group with no history of trauma was 12%, whereas that of the group with a history of trauma was 14% (P = .36). Those patients with a history of shoulder trauma who waited longer than 24 months had higher retear rates (20%) than those who had their surgery earlier (13%) (P = .040). CONCLUSION: Recollection of a traumatic initiating event had little effect on the outcome of arthroscopic rotator cuff repair. Duration of symptoms was important in predicting retears if patients recalled a specific initiating event but not in patients who did not recall any specific initiating event. Patients with a history of trauma should be encouraged to have their rotator cuff tear repaired within 2 years.

The effect of concomitant glenohumeral joint capsule release during rotator cuff repair--a comparative study.

BACKGROUND: There is debate as to whether to operate or to defer surgery on patients with concomitant rotator cuff tear and shoulder stiffness. The purpose of this study was therefore to compare the outcomes in those patients who had both their rotator cuff tear and shoulder stiffness treated with the outcomes of patients who had a rotator cuff repair but no stiffness. METHODS: Twenty-five patients formed the stiffness group (receiving a concomitant rotator cuff repair and manipulation under anesthesia ± arthroscopic capsular release for preoperative ipsilateral stiffness), and a chronologically matched group of 170 rotator cuff repair-only patients formed the nonstiffness group. Patients ranked their pain and function scores preoperatively and at 1 week, 6 weeks, 12 weeks, 6 months, and 2 years postoperatively; examiners recorded range of motion, strength, and presence of impingement signs. Repair integrity was determined using ultrasound. RESULTS: Patients from both groups had significantly improved clinical outcomes at the 2-year follow-up compared with preoperative values. Range of motion was similar between groups at 2 years for forward flexion, abduction, and external rotation, whereas the nonstiffness group had a superior range of internal rotation (P = .014). Stiffness patients had 0 of 25 (0%) retears at 2 years compared with 34 of 170 (20%) in the nonstiffness group (P = .009). CONCLUSIONS: The good outcomes of rotator cuff repair with glenohumeral capsular release disproved our hypothesis and suggest that there is no advantage in delaying repair of a rotator cuff tear to allow stiffness to resolve and that stiffness confers an advantage in terms of repair integrity. LEVEL OF EVIDENCE: Level III; Retrospective Cohort Design; Treatment Study.

Effect of high-intensity intermittent exercise on postprandial plasma triacylglycerol in sedentary young women.

High-intensity intermittent exercise (HIIE) such as the 30-s Wingate test attenuates postprandial triacylglycerol (TG), however, the ability of shorter versions of HIIE to reduce postprandial TG is undetermined. Thus, the effect of 8-s sprinting bouts of HIIE on blood TG levels of 12 females after consumption of a high-fat meal (HFM) was examined. Twelve young, sedentary women (BMI 25.1 ± 2.3 kg/m²; age 21.3 ± 2.1 years) completed a maximal oxygen uptake test and then on different days underwent either an exercise or a no-exercise postprandial TG condition. Both conditions involved consuming a HFM after a 12-hr fast. The HFM, in milkshake form provided 4170 kJ (993 Kcal) of energy and 98 g fat. Order was counter-balanced. In the exercise condition participants completed 20-min of HIIE cycling consisting of repeated bouts of 8 s sprint cycling (100-115 rpm) and 12 s of active rest (easy pedaling) 14 hr before consuming the HFM. Blood samples were collected hourly after the HFM for 4 hr. Total postprandial TG was 13% lower, p = .004, in the exercise (5.84 ± 1.08 mmol L⁻¹ 4 h⁻¹) compared with the no-exercise condition (6.71 ± 1.63 mmol L⁻¹ 4 h⁻¹). In conclusion, HIIE significantly attenuated postprandial TG in sedentary young women.

Diagnosis and Management of Constitutional Mismatch Repair Deficiency Syndrome.

Constitutional mismatch repair deficiency (CMMRD) syndrome is a rare autosomal recessive genetic disorder that has little more than 200 total cases reported as of 2020. Whereas a single mutation in genes responsible for mismatch repair causes the autosomal dominant Lynch syndrome (LS), CMMRD is caused by biallelic heterozygous defects: distinct deleterious mutations on each allele for a single gene. As the disease is exceedingly rare and may present via a wide variety of signs, including neurofibromatosis type 1- and Lynch Syndrome-associated malignancies, diagnosis and subsequent surveillance are complex with suggested methods published by the International Replication Repair Deficiency Consortium. We report here the history and management of a patient whose newly diagnosed CMMRD was managed with both curative and prophylactic surgical treatment.

Changes in Pediatric Non-accidental Trauma Emergency Department Visits During and Following the COVID-19 Lockdown.

A level 1 pediatric trauma registry database was examined for all non-accidental trauma (NAT) emergency department visits between 2016 and 2021, and average injury severity score assigned to those patients with physical injuries over 2019-2021. There was a decline in NAT visits in 2020 (267) from prior years (343 visits average over 2016-2019), with subsequent increase in 2021 (548). Injury severity score increased (ISS) in 2020 (7.3) when compared to 2019 (5.71), with a decline in average ISS in 2021 (5.42). This data highlights the potential for missed abuse during closures with increased detection following reopening. Our data regarding ISS demonstrates the pediatric population is at risk of more severe abuse during times of familial stress. We need increased awareness that periods of vulnerability to NAT exist, as seen during the COVID-19 pandemic.

P-wave durations from automated electrocardiogram analysis to predict atrial fibrillation and mortality in heart failure.

BACKGROUND: P-wave indices have been used to predict incident atrial fibrillation (AF), stroke, and mortality. However, such indices derived from automated ECG measurements have not been explored for their predictive values in heart failure (HF). We investigated whether automated P-wave indices can predict adverse outcomes in HF. METHODS: This study included consecutive Chinese patients admitted to a single tertiary centre, presenting with HF but without prior AF, and with at least one baseline ECG, between 1 January 2010 and 31 December 2016, with last follow-up of 31 December 2019. RESULTS: A total of 2718 patients were included [median age: 77.4, interquartile range (IQR): (66.9-84.3) years; 47.9 males]. After a median follow-up of 4.8 years (IQR: 1.9-9.0 years), 1150 patients developed AF (8.8/year), 339 developed stroke (2.6/year), 563 developed cardiovascular mortality (4.3/year), and 1972 had all-cause mortality (15.1/year). Compared with 101-120 ms as a reference, maximum P-wave durations predicted new-onset AF at ≤90 ms [HR: 1.17(1.11, 1.50), P < 0.01], 131-140 ms [HR: 1.29(1.09, 1.54), P < 0.001], and ≥141 ms [HR: 1.52(1.32, 1.75), P < 0.001]. Similarly, they predicted cardiovascular mortality at ≤90 ms [HR: 1.50(1.08, 2.06), P < 0.001] or ≥141 ms [HR: 1.18(1.15, 1.45), P < 0.001], and all-cause mortality at ≤90 ms [HR: 1.26(1.04, 1.51), P < 0.001], 131-140 ms [HR: 1.15(1.01, 1.32), P < 0.01], and ≥141 ms [HR: 1.31(1.18, 1.46), P < 0.001]. These remained significant after adjusting for significant demographics, past co-morbidities, P-wave dispersion, and maximum P-wave amplitude. CONCLUSIONS: Extreme values of maximum P-wave durations (≤90 ms and ≥141 ms) were significant predictors of new-onset AF, cardiovascular mortality, and all-cause mortality.

Fragmented QRS Is Independently Predictive of Long-Term Adverse Clinical Outcomes in Asian Patients Hospitalized for Heart Failure: A Retrospective Cohort Study.

Background: Fragmented QRS (fQRS) results from myocardial scarring and predicts cardiovascular mortality and ventricular arrhythmia (VA). We evaluated the prevalence and prognostic value of fQRS in Asian patients hospitalized for heart failure. Methods and Results: This was a retrospective cohort study of adult patients hospitalized for heart failure between 1st January 2010 and 31st December 2016 at a tertiary center in Hong Kong. The baseline ECG was analyzed. QRS complexes (<120 ms) with fragmented morphology in ≥2 contiguous leads were defined as fQRS. The primary outcome was a composite of cardiovascular mortality, VA, and sudden cardiac death (SCD). The secondary outcomes were the components of the primary outcome, myocardial infarction, and new-onset atrial fibrillation. In total, 2,182 patients were included, of whom 179 (8.20%) had fQRS. The follow-up duration was 5.63 ± 4.09 years. fQRS in any leads was associated with a higher risk of the primary outcome (adjusted hazard ratio (HR) 1.428 [1.097, 1.859], p = 0.001), but not myocardial infarction or new-onset atrial fibrillation. fQRS in >2 contiguous leads was an independent predictor of SCD (HR 2.679 [1.252, 5.729], p = 0.011). In patients without ischaemic heart disease (N = 1,396), fQRS in any leads remained predictive of VA and SCD (adjusted HR 3.526 [1.399, 8.887], p = 0.008, and 1.873 [1.103, 3.181], p = 0.020, respectively), but not cardiovascular mortality (adjusted HR 1.064 [0.671, 1.686], p = 0.792). Conclusion: fQRS is an independent predictor of cardiovascular mortality, VA, and SCD. Higher fQRS burden increased SCD risk. The implications of fQRS in heart failure patients without ischaemic heart disease require further studies.

Derivation of an electronic frailty index for predicting short-term mortality in heart failure: a machine learning approach.

AIMS: Frailty may be found in heart failure patients especially in the elderly and is associated with a poor prognosis. However, assessment of frailty status is time-consuming, and the electronic frailty indices developed using health records have served as useful surrogates. We hypothesized that an electronic frailty index developed using machine learning can improve short-term mortality prediction in patients with heart failure. METHODS AND RESULTS: This was a retrospective observational study that included patients admitted to nine public hospitals for heart failure from Hong Kong between 2013 and 2017. Age, sex, variables in the modified frailty index, Deyo's Charlson co-morbidity index (≥2), neutrophil-to-lymphocyte ratio (NLR), and prognostic nutritional index at baseline were analysed. Gradient boosting, which is a supervised sequential ensemble learning algorithm with weak prediction submodels (typically decision trees), was applied to predict mortality. Variables were ranked in the order of importance with a total score of 100 and used to build the frailty models. Comparisons were made with decision tree and multivariable logistic regression. A total of 8893 patients (median: age 81, Q1-Q3: 71-87 years old) were included, in whom 9% had 30 day mortality and 17% had 90 day mortality. Prognostic nutritional index, age, and NLR were the most important variables predicting 30 day mortality (importance score: 37.4, 32.1, and 20.5, respectively) and 90 day mortality (importance score: 35.3, 36.3, and 14.6, respectively). Gradient boosting significantly outperformed decision tree and multivariable logistic regression. The area under the curve from a five-fold cross validation was 0.90 for gradient boosting and 0.87 and 0.86 for decision tree and logistic regression in predicting 30 day mortality. For the prediction of 90 day mortality, the area under the curve was 0.92, 0.89, and 0.86 for gradient boosting, decision tree, and logistic regression, respectively. CONCLUSIONS: The electronic frailty index based on co-morbidities, inflammation, and nutrition information can readily predict mortality outcomes. Their predictive performances were significantly improved by gradient boosting techniques.

Comparing clinical outcomes between rotator cuff repairs, SLAP repairs, and combined repairs.

BACKGROUND: Superior labrum lesion from anterior to posterior (SLAP) often presents together with other shoulder pathologies such as rotator cuff tear (RCT), but it is uncertain if repairing both SLAP and RCT has superior clinical outcomes over isolated repairs of SLAP and RCT. MATERIALS AND METHODS: This was a retrospective cohort study with prospectively collected data, reviewing 157 patients who underwent arthroscopic repair of either RCT, SLAP (type II lesion), or both. Before surgery and after 6 weeks, 12 weeks, and 24 weeks, shoulder objective range of motion and strength were measured, patient-reported function and pain was assessed by the modified L'Insalata questionnaire with a Likert scale, and complications after each repair were examined. RESULTS: At 24 weeks after surgery, the combined group (n = 22) and SLAP group (n = 47) had significantly higher forward flexion (165° ± 4° and 167° ± 4° vs. 154° ± 3°, P = .01 and P = .01), external rotation strength (82 ± 6 N, 81 ± 6 N vs. 61 ± 3 N, P = .01 and P = .01), and abduction strength (94 ± 14 N, 78 ± 8 N vs. 53 ± 3 N, P = .001 and P = .02) compared with the rotator cuff tear repair (RCR) group (n = 88). The combined group also had stronger internal rotation than the RCR group (107 ± 12 N vs. 72 ± 4 N, P = .02). Function and pain improved from "severe-moderate" to "moderate-mild" in all groups after surgery. CONCLUSION: Repairing RCT and SLAP tears together results in significant clinical benefits compared to repairing just RCT and analogous results against SLAP-only repair.

Does proximal porous coating in short-stem humeral arthroplasty reduce stress shielding?

CONTEXT: Short-stem humeral designs in shoulder arthroplasty have been introduced recently. A retrospective cohort study was conducted to determine if newer proximal porous titanium coating in humeral short stems produced clinical and radiologic improvements. METHOD: Short-stem humeral implants (Tornier Ascend, Wright Medical) were used in 46 anatomical total shoulder replacements from October 2012 to December 2015. Clinical and radiologic measures were analyzed at one- and two-year follow-up. RESULTS: Nineteen shoulders received earlier grit blasted stems (Ascend Monolithic), and 27 shoulders received the later stems with proximal titanium porous coating (Ascend Flex). At two-year follow-up, radiographic changes and stress shielding were similar. Medial cortical thinning were more frequently observed in Monolithic (18 of 19) compared to Flex stems (19 of 27) on the PA films, though this was not statistically significant (P = 0.061). Clinical outcome scores improved regardless of the stem type used and independent of the radiologic adaptations on plain films. One participant with the Ascend Flex developed glenoid component failure and rotator cuff tear and was subsequently revised. DISCUSSION: Clinical and radiological outcomes are similar in both short-stem designs. Proximal titanium porous coating may reduce medial calcar cortical thinning but it does not prevent it. KEY MESSAGE: When compared to similarly designed uncoated grit-blasted stems, proximally porous coated humeral short stems produced similar clinical and radiological results. The proximal titanium porous coating may reduce medial cortical thinning.