Comparative efficacy of low-volume retrobulbar anesthesia using three commercial local anesthetics in adult horses.

OBJECTIVE: To compare the efficacy of low-volume (5-mL) locoregional retrobulbar anesthesia ("retrobulbar block") by use of 3 commercial local anesthetic formulations. ANIMALS: 8 healthy adult mares. METHODS: A block-randomized, masked, controlled design was used. A single ultrasound-guided retrobulbar block was performed with 2% lidocaine, 2% mepivacaine, or 0.5% bupivacaine (n = 5 eyes/group). Contralateral eyes served as untreated controls. End points performed at baseline and time intervals up to 24 hours postblock included the following: assessment of neurophthalmic reflexes/responses, intraocular pressure, and vertical pupil diameter measurement, corneal and periocular esthesiometry, and observation for adverse effects. RESULTS: Low-volume block did not result in increased intraocular pressure or other adverse effects at any time point in any treatment group. Statistically significant corneal anesthesia (P < .001) was observed 1 minute after block in all groups, persisting through 4 hours after lidocaine or mepivacaine block and through 24 hours after bupivacaine block. Clinically significant periocular anesthesia was not observed in any group. Significant vertical pupil diameter increase (P < .05) was observed for up to 4 hours after lidocaine or mepivacaine block and 6 hours after bupivacaine block. CLINICAL RELEVANCE: Low-volume retrobulbar block with any of the 3 local anesthetic drugs evaluated was not associated with adverse effects. In terms of efficacy, mepivacaine block showed no clinical advantage over lidocaine block. However, bupivacaine block induced comparatively rapid and sustained corneal anesthesia. In comparison to published findings using a larger injection volume, low-volume retrobulbar block with lidocaine produced clinically comparable corneal anesthesia. However, periocular soft tissue anesthesia was not achieved with any local anesthetic drug at low volume.

The effect of feeding on serum concentrations of cobalamin, folate, trypsin-like immunoreactivity, and pancreatic lipase immunoreactivity in dogs with signs of chronic gastrointestinal disease.

BACKGROUND: It is unknown if serum concentrations of cobalamin, folate, canine pancreatic lipase immunoreactivity (cPLI), and canine trypsin-like immunoreactivity (cTLI) obtained postprandially are equivalent to measurements obtained after withholding food in dogs with suspected gastrointestinal disease. HYPOTHESIS/OBJECTIVES: Measurements of serum concentrations of cobalamin, folate, cPLI, and cTLI postprandially will be equivalent to measurements after 12 hours of withholding food in dogs with signs of chronic gastrointestinal disease. Changes observed will not alter clinical interpretation. ANIMALS: 51 client-owned dogs with signs of gastrointestinal disease. METHODS: Prospective single arm clinical trial. Serum concentrations of cobalamin, folate, cPLI and cTLI 2, 4, and 8 hours postprandially were compared by equivalence testing to values after withholding food for 12 hours (baseline). RESULTS: Mean serum cobalamin concentrations 2 hours (498.1 ± 213.1 ng/L; P = 0.024) and 4 hours (501.9 ± 207.4 ng/L; P = 0.008) postprandial were equivalent to baseline (517.3 ± 211.5 ng/L). Mean serum cTLI 2 hours (31.3 ± 14 µg/L; P < 0.001) and 4 hours (29.6 ± 13.1 µg/L; P = 0.027) postprandial were equivalent to baseline (31.1 ± 15 µg/L). Mean serum folate concentration 2 hours postprandial (15 ± 7.7 µg/L) was equivalent to baseline (13.7 ± 8.3 µg/L; P < 0.001). Equivalence could not be assessed for cPLI due to results below the lower limit of quantification. Feeding altered the clinical interpretation in 27% (cobalamin), 35% (folate), 20% (cTLI), and 12% (cPLI) of dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The clinical interpretation for a substantial number of samples changed after feeding, therefore withholding food before sample collection is prudent.

Primary outcomes from Partner2Lose: A randomized controlled trial to evaluate partner involvement on long-term weight loss.

Background: Partner support is associated with better weight loss outcomes in observational studies, but randomized trials show mixed results for including partners. Unclear is whether teaching communication skills to couples will improve weight loss in index participants. Purpose: To compare the efficacy of a partner-assisted intervention versus participant-only weight management program on long-term weight loss. Methods: This community-based study took place in Madison, WI. Index participants were eligible if they met obesity guideline criteria to receive weight loss counseling, were aged 74 years or younger, lived with a partner, and had no medical contraindications to weight loss; partners were aged 74 years or younger and not underweight. Couples were randomized 1:1 to a partner-assisted or participant-only intervention. Index participants in both arms received an evidence-based weight management program. In the partner-assisted arm, partners attended half of the intervention sessions, and couples were trained in communication skills. The primary outcome was index participant weight at 24 months, assessed by masked personnel; secondary outcomes were 24-month self-reported caloric intake and average daily steps assessed by an activity tracker. General linear mixed models were used to compare group differences in these outcomes following intent-to-treat principles. Results: Among couples assigned to partner-assisted (n=115) or participant-only intervention (n=116), most index participants identified as female (67%) and non-Hispanic White (87%). Average baseline age was 47.27 years (SD 11.51 years) and weight was 106.55 kg (SD 19.41 kg). The estimated mean 24-month weight loss was similar in the partner-assisted (2.66 kg) and participant-only arms (2.89 kg) (estimated mean difference, 0.23 kg [95% CI, -1.58, 2.04 kg]). There were no differences in 24-month average daily caloric intake (50 cal [95% CI: -233, 132 cal]) or steps (806 steps [95% CI: -1675, 64 steps]). The percentage of participants reporting an adverse event with at least possible attribution to the intervention did not differ by arm (partner-assisted: 9%, participant-only, 3%, p=0.11). Conclusions: Partner-assisted and individual weight management interventions led to similar outcomes in index participants. Trial registration: Clinicaltrials.gov NCT03801174.

Antimicrobial effects of blue light therapy against cutibacterium acnes: optimal dosing and impact of serial treatments.

Background: Blue light therapy (BLT) is a Food and Drug Administration cleared modality used in dermatology as an effective treatment of acne. The primary purpose of this study is to determine if there are dose-dependent antimicrobial effects of BLT against Cutibacterium acnes (C. acnes). Methods: A known strain of C. acnes was grown on chocolate agar in a controlled laboratory environment under anaerobic conditions for 1 week. After 1 week, 2-3 colonies of C. acnes were isolated and transferred to broth medium to incubate for 2 or 7 days. Broth vials (treatment arm) then underwent 1 of 6 different blue light dosing treatment regimens and a duplicate broth vial served as a control left open to the same environment. The BLT regimens were a single treatment of 25 J/cm2, 50 J/cm2, 75 J/cm2, 100 J/cm2, 2 serial treatments of 50 J/cm2 separated by 24 hours, or 2 serial treatments of 75 J/cm2 separated by 24 hours. The Omnilux Blue device (415 nm wavelength) was used for all BLT treatments and delivered, on average, 1.68 ± 0.004 J/min. Following treatment, the control and treatment broth samples were plated on chocolate agar and allowed to grow for 7 days. After 7 days, plates were counted and colony forming units (CFUs) were calculated. Six trials were completed for each BLT dosing regimen based on an a priori power analysis of 6 individual 2-sided t-tests. Comparisons in the primary outcome were made via mixed-effects analysis of variance with replicate as a random effect. Results: All BLT treatment regimens resulted in significantly fewer CFUs than their aggregate control plate CFUs (P < .05 for all). Furthermore, in 2-way comparison of CFUs between BLT treatment groups, a single treatment of 75 J/cm2 did lead to significantly less growth than 25 J/cm2 (P = .017) and 50 J/cm2 (P = .017). There were no improved antimicrobial effects with serial treatments when comparing 2 doses of 50 J/cm2 with a single dose of 100J/cm2, nor were 2 doses of 75 J/cm2 more efficacious than 100 J/cm2. Using the Omnilux Blue device, it took 44.8 minutes to deliver a 75 J/cm2 dose. Conclusion: BLT is an effective antimicrobial agent against this single virulent strain of C. acnes. Treatment dosing of 75 J/cm2 was identified to be the most effective dose per unit time. Serial treatments did not lead to superior antimicrobial effects over a single, high-dose treatment.

Comparison of D-dimer concentration and thromboelastography for diagnosis of cerebrovascular accidents in dogs: A retrospective study.

BACKGROUND: Cerebrovascular accidents (CVAs) in dogs are diagnosed using magnetic resonance imaging (MRI). This modality is sometimes unavailable, and CVAs can resemble other lesions on MRI. D-dimer concentration and thromboelastography (TEG) are utilized in human medicine in addition to diagnostic imaging to support diagnosis of CVAs, but their use in veterinary patients has not been assessed. OBJECTIVE: Assess utility of blood D-dimer concentration and TEG in supporting the imaging diagnosis of CVAs in dogs. ANIMALS: Sixty-eight client-owned dogs with neurologic signs that had brain MRI and D-dimer concentration or TEG performed. METHODS: Multicenter, retrospective study. The incidence of abnormal D-dimer concentration or TEG was compared between patients with MRI evidence of CVA and a control population. Analysis methods included Fisher's exact test or Chi-squared test for association and comparison of independent proportions. RESULTS: Neither D-dimer concentration nor TEG was significantly associated with a CVA (P = .38 and .2, respectively). D-dimer testing was performed in a low-risk population and showed low sensitivity (30.8%; 95% confidence interval [CI], 10%-61%) and high specificity (86.4%; 95% CI, 64%-96%) for CVA diagnosis. Thromboelastography was performed in a high-risk population and showed moderate sensitivity (64.3%; 95% CI, 44%-81%) and specificity (66.7%; 95% CI, 24%-94%) for CVA diagnosis. Abnormal D-dimer concentration or TEG were not helpful in differentiating hemorrhagic from ischemic stroke (P = .43 and .41, respectively). CONCLUSIONS: Although blood D-dimer concentration or TEG alone are not diagnostic of CVAs in dogs, a positive D-dimer result supports additional testing for CVA.

Temporomandibular Joint Gape Angles in Normal and Painful Domestic Felines.

The purpose of this study was to determine and compare the gape angles (temporomandibular joint range of motion with mouth opening) of conscious and anesthetized domestic felines and to compare gape angles with and without evidence of oral pain. This prospective study evaluated the gape angle of 58 domestic felines. The cats were grouped into painful (n = 33) and nonpainful cohorts (n = 25) and gape angles were compared during conscious and anesthetized conditions. Gape angles were determined based on measurements of the maximal interincisal distance and lengths of the mandible and maxilla followed by calculation of the law of cosines. The mean feline gape angle (standard deviation) was determined to be 45.3° (8.6°) and 50.8° (6.2°) for conscious and anesthetized felines respectively. There was no significant difference between painful and non-painful feline gape angles during conscious (P = .613) or anesthetized (P = .605) evaluations. There was a significant difference between anesthetized and conscious gape angles (P < .001) for both painful and non-painful cohorts. This study determined the standardized, normal feline temporomandibular joint (TMJ) gape angle in both conscious and anesthetized states. This study suggests that the feline gape angle is not a useful indicator of oral pain. By determining the feline gape angle, which was previously unknown, further evaluation of its utility as a non-invasive clinical parameter for evaluation of restrictive TMJ motions as well as its use for serial evaluations may be pursued.

Comparison of three-dimensional printed patient-specific guides versus freehand approach for radial osteotomies in normal dogs: Ex vivo model.

OBJECTIVE: To compare the accuracy of three-dimensional (3D) printed patient-specific guide (PSG) with a freehand (FH) approach for radial osteotomies in ex vivo normal dogs. STUDY DESIGN: Experimental study. ANIMALS: Twenty four ex vivo thoracic limb pairs from normal beagle dogs. METHODS: Computed tomography (CT) images were collected preoperatively and postoperatively. Three osteotomies tested (n = 8/group) were: (1) uniplanar 30° frontal plane wedge ostectomy, (2) oblique plane (30° frontal, 15° sagittal) wedge ostectomy, and (3) single oblique plane osteotomy (SOO, 30° frontal, 15° sagittal, and 30° external). Limb pairs were randomized to a 3D PSG or FH approach. The resultant osteotomies were compared with virtual target osteotomies by surface shape-matching postoperative to the preoperative radii. RESULTS: The mean ± standard deviation osteotomy angle deviation for all 3D PSG osteotomies (2.8 ± 2.8°, range 0.11-14.1°) was less than for the FH osteotomies (6.4 ± 6.0°, range 0.03-29.7°). No differences were found for osteotomy location in any group. In total, 84% of 3D PSG osteotomies were within 5° deviance from the target compared to 50% of freehand osteotomies. CONCLUSION: Three-dimensional PSG improved FH accuracy of osteotomy angle in select planes and the most complex osteotomy orientation in a normal ex vivo radial model. CLINICAL SIGNIFICANCE: Three-dimensional PSGs provided more consistent accuracy, which was most notable in complex radial osteotomies. Future work is needed to investigate guided osteotomies in dogs with antebrachial bone deformities.

Surgical transversus abdominis plane block with liposomal bupivacaine at cesarean: a pilot randomized trial.

BACKGROUND: Postcesarean pain control is challenging. In addition to intrathecal morphine, recent studies have shown that liposomal bupivacaine administered via conventional transversus abdominis plane block reduces postcesarean opioid use. However, whether the administration of liposomal bupivacaine via a surgical approach also reduces opioid use is unknown. OBJECTIVE: This study aimed to investigate whether the administration of liposomal bupivacaine via surgical transversus abdominis plane block (TAP block) reduces the cumulative dose of opioids administered in the first 48 hours after cesarean delivery among participants who also receive intrathecal morphine. STUDY DESIGN: This was a pilot single-blind randomized controlled trial of 60 parturients undergoing cesarean delivery at a community tertiary referral hospital staffed by academic physicians. Immediately before fascial closure during cesarean delivery, a total of 80 mL of dilute bupivacaine plus liposomal bupivacaine or dilute bupivacaine alone was administered via surgical transversus abdominis plane block (40 mL on each side). The primary outcome was a median cumulative opioid dose received within the first 48 hours after cesarean delivery measured in morphine milligram equivalents. In addition, opioid use at other time points, pain scores, and participant satisfaction were assessed. A sample size of 60 was determined to be adequate to inform a potential future adequately powered randomized trial. The primary outcome of morphine milligram equivalents and pain scores were compared using a Wilcoxon rank-sum test. RESULTS: Between October 11, 2021, and August 29, 2022, 60 participants were randomized and analyzed: 31 were allocated to liposomal bupivacaine plus regular bupivacaine (intervention group), and 29 were allocated to regular bupivacaine alone (control group). Participants allocated to the intervention group used a median cumulative dose of 2 morphine milligram equivalents of opioids (interquartile range, 0-24) in the first 48 hours compared with 8 morphine milligram equivalents (interquartile range, 0-40) among participants allocated to the control group (P=.236). The percentage of participants who used ≤15 morphine milligram equivalents of opioids was 61% in the intervention arm and 41% in the control arm (P=.123), and the percentage who used zero opioids was 45% in the intervention arm and 34% in the control arm (P=.399). The total number of opioid pills prescribed at discharge was fewer in the intervention arm than in the control arm (P=.029). Patient satisfaction with the intervention group and control group was similar. CONCLUSION: Our pilot study suggests that liposomal bupivacaine administered via surgical transversus abdominis plane block is worth critical evaluation as an adjunctive analgesic modality in an adequately powered randomized trial.

Intraoral Radiographic Interpretation Agreement Between Veterinary Students, Veterinary Dental Residents and Veterinary Dental Specialists.

This study evaluated observer variations in the interpretation of radiographic evidence for periodontal disease, tooth resorption, and endodontic disease in dogs. Forty dental radiographs were evaluated for 12 different parameters (periapical destruction of bone, wider than expected root canal, narrower than expected root canal, apical root resorption, loss of alveolar bone, external surface resorption, external replacement resorption, external inflammatory resorption, external cervical root resorption, internal surface resorption, internal replacement resorption, internal inflammatory resorption). Interpretations by 20 veterinary dentists, 10 veterinary dental residents, and 10 veterinary students were analyzed for consistency within groups and between groups by intraclass correlation coefficients (ICCs [95% CI]). Additionally, the agreement rate between groups compared to histopathological diagnosis, when available, and to a consensus group were evaluated. The results showed fair to good interobserver agreement for all participants when looking at all questions simultaneously (0.578 [0.515-0.635]) and with the consensus group (0.483 [0.451-0.517]). However, questions pertaining to various types of tooth resorption scored the lowest ICCs ranging from 0.005 (-0.311 to 0.321) to 0.189 (-0.105 to 0.402) across individual groups. Students had the lowest agreement compared to the consensus group for all questions (0.383 [0.347-0.421]) with fair to good agreement involving groups of residents (0.501 [0.465-0.538]), recently boarded diplomates (0.541 [0.506-0.578]), and more experienced diplomates (0.545 [0.510-0.582]). While dental radiographs are essential for clinical decision making, this study shows that interpretation of radiographs is highly subjective.

Quantification of Iliac Arterial Blood Velocity in Stenotic Phantom and Porcine Models Using Quantitative Digital Subtraction Angiography.

PURPOSE: To assess the feasibility of using quantitative digital subtraction angiography (qDSA) to quantify arterial velocity in phantom and porcine stenotic iliac artery models. MATERIALS AND METHODS: Varying stenoses (mild, <50%; moderate, 50%-70%; and severe, >70%) were created in a silicone iliac artery phantom using vessel loops. Two-dimensional digital subtraction angiographies (DSAs) were performed, with velocities calculated using qDSA. qDSA velocities were compared with flow rates and velocities measured with an ultrasonic flow probe. Two-dimensional DSAs of the common and external iliac arteries were then performed in 4 swine (mean weight, 63 kg) before and after a severe stenosis (>70%) was created in the iliac artery using 3-0 silk suture. Peak systolic velocities on pulsed wave Doppler ultrasound (US) before and after stenosis creation were correlated with the qDSA velocities. Pearson correlation, linear regression, and analysis of variance were used for analysis. RESULTS: In the phantom study, ultrasonic probe velocities positively correlated with downstream qDSA (r = 0.65; P < .001) and negatively correlated with peristenotic qDSA velocities (r = -0.80; P < .001). In the swine study, statistically significant reductions in external iliac arterial velocity were noted on US and qDSA after stenosis creation (P < .05). US and qDSA velocities strongly correlated for all flow states with both 50% and 100% contrast concentrations (r = 0.82 and r = 0.74, respectively), with an estimated US-to-qDSA ratio of 1.3-1.5 (P < .001). qDSA velocities with 50% and 100% contrast concentrations also strongly correlated (r = 0.78; P < .001). CONCLUSIONS: In both phantom and swine stenosis models, changes in iliac arterial velocity could be quantified with qDSA, which strongly correlated with standard-of-care US.

Examining the Critical Need for Tailored Adolescent Opioid Education: A National Study.

OBJECTIVE: Prescription opioid education can be a preventative measure for opioid misuse. However, most research focuses on adult perspectives rather than adolescents. This study aimed to understand adolescents' attitudes, perceptions, knowledge about prescription opioids, and preferences and prior educational exposure to opioid safety. METHODS: Data were collected from November to December 2020. Quota sampling through Qualtrics was used to recruit a national sample of 13- to 18-year-old adolescents who lived in the United States and could understand English. RESULTS: A total of 774 responses were analyzed. The most frequently reported source of opioid information was speaking with parents (72%). More than half (54.7%) of participants preferred technology-based education. Participants with a personal history of opioid prescription scored no differently on safe handling and storage of opioids. There was a strong relationship between participants who reported prior knowledge of what opioids are and stopping their friend from using an opioid medication for non-medical purposes (χ2 (1, N = 684) = 3.5; p = 0.042). Participants with prior education on opioid disposal did not know that -returning opioids to the pharmacy was correct (χ2 (1, N = 425) = 3.8; p = 0.254). CONCLUSIONS: Participants were less knowledgeable about safe storage and disposal of opioids, preferred technology-based education, and were extremely likely to talk to their parents about opioid information. Findings reaffirm the significance of opioid safety education and communication between adolescents and parents. Adolescent demographic characteristics, preferences, and prior knowledge should be considered when providing opioid safety education.

Effect of esomeprazole with and without a probiotic on fecal dysbiosis, intestinal inflammation, and fecal short-chain fatty acid concentrations in healthy dogs.

BACKGROUND: Proton pump inhibitors can cause diarrhea and a transient increase in fecal dysbiosis index in dogs. It is unknown if concurrent probiotic administration mitigates these effects. OBJECTIVE/HYPOTHESIS: To assess the fecal Canine Microbial Dysbiosis Index (CMDI), fecal short chain fatty acid (SCFA), and fecal calprotectin concentrations in dogs administered esomeprazole with and without a probiotic. ANIMALS: Eleven healthy dogs. METHODS: Prospective, within-subjects before and after study. All dogs received 7-day courses of esomeprazole (1 mg/kg PO q 24h) alone followed by esomeprazole with a probiotic (15 billion CFU/kg), separated by a 4-week washout period. Data were compared between phases using mixed effects ANOVA or generalized estimating equations with post-hoc Holm adjustment for 2-way comparisons. RESULTS: Compared to baseline (mean CMDI -2.66, SD 3.04), fecal CMDI was not different with esomeprazole administration alone (mean CMDI -1.48, SD 3.32, P = .08), but there was a significant increase (Diff 3.05, 95% CI [1.37, 4.74], P < .001, Effect size 2.02) when esomeprazole and a probiotic were administered concurrently (mean CMDI 0.39, SD 2.83). CMDI was significantly higher when esomeprazole was administered with a probiotic than alone (Diff 1.87, 95% CI [0.19, 1.87], P = .02, Effect size 1.24). Fecal calprotectin and SCFA concentrations did not differ between phases. The occurrence of vomiting and diarrhea was not different from baseline when esomeprazole was administered alone (36%/27%) or with a probiotic (46%/9%). CONCLUSIONS AND CLINICAL IMPORTANCE: In healthy dogs, concurrent administration of a probiotic is unlikely to lessen adverse effects associated with esomeprazole administration.

Correcting Posterior Paraspinal Muscle Computed Tomography Density for Intravenous Contrast Material Independent of Sex and Vascular Phase.

PURPOSE: Intravenous contrast poses challenges to computed tomography (CT) muscle density analysis. We developed and tested corrections for contrast-enhanced CT muscle density to improve muscle analysis and the utility of CT scans for the assessment of myosteatosis. MATERIALS AND METHODS: Using retrospective images from 240 adults who received routine abdominal CT imaging from March to November 2020 with weight-based iodine contrast, we obtained paraspinal muscle density measurements from noncontrast (NC), arterial, and venous-phase images. We used a calibration sample to develop 9 different mean and regression-based corrections for the effect of contrast. We applied the corrections in a validation sample and conducted equivalence testing. RESULTS: We evaluated 140 patients (mean age 52.0 y [SD: 18.3]; 60% female) in the calibration sample and 100 patients (mean age 54.8 y [SD: 18.9]; 60% female) in the validation sample. Contrast-enhanced muscle density was higher than NC by 8.6 HU (SD: 6.2) for the arterial phase (female, 10.4 HU [SD: 5.7]; male, 6.0 HU [SD:6.0]) and by 6.4 HU [SD:8.1] for the venous phase (female, 8.0 HU [SD: 8.6]; male, 4.0 HU [SD: 6.6]). Corrected contrast-enhanced and NC muscle density was equivalent within 3 HU for all correctionns. The -7.5 HU correction, independent of sex and phase, performed well for arterial (95% CI: -0.18, 1.80 HU) and venous-phase data (95% CI: -0.88, 1.41 HU). CONCLUSIONS: Our validated correction factor of -7.5 HU renders contrast-enhanced muscle density statistically similar to NC density and is a feasible rule-of-thumb for clinicians to implement.

Bone quality in total shoulder arthroplasty: a prospective study correlating computed tomography Hounsfield units with thumb test and fracture risk assessment tool score.

Background: To evaluate if Hounsfield units (HU) measured on preoperative computed tomography (CT) scans at the anatomic neck of the proximal humerus correlates with intraoperative findings of the "thumb test" in assessment of bone quality in shoulder arthroplasty patients. Methods: Primary anatomic total shoulder and reverse total shoulder arthroplasty patients from 2019-2022 with an available preoperative CT scan of the operative shoulder were prospectively enrolled at a single center with 3 surgeons who perform shoulder arthroplasty. The "thumb test" was performed intraoperatively; a positive test signified "good bone." Demographic information, including prior dual x-ray absorptiometry scans, was extracted from the medical record. HU at the cut surface of the proximal humerus were calculated, as was cortical bone thickness on preoperative CT. Fracture risk assessment tool (FRAX) scores were calculated for 10-year risk of osteoporotic fracture. Results: A total of 149 patients were enrolled. Mean age was 67.6 ± 8.5 years with 69 (46.3%) being males. Patients with a negative thumb test were significantly older (72.3 ± 6.6 vs. 66.5 ± 8.6 years; P < .001) than those with a positive thumb test. Males were more likely to have a positive thumb test than females (P = .014). Patients with a negative thumb test had significantly lower HUs on preoperative CT (16.3 ± 29.7 vs. 51.9 ± 35.2; P < .001). Patients with a negative thumb test had a higher mean FRAX score (14.1 ± 7.9 vs. 8.0 ± 4.8; P < .001). Receiver operator curve analysis was performed to identify a cut-off value for CT HU of 36.67, above which the thumb test is likely to be positive. Furthermore, receiver operator curve analysis also identified optimal cut-off values for 10-year risk of fracture by FRAX score of 7.75 HU, below which the thumb test is likely to be positive. Fifty patients were at high risk based on FRAX and HU; surgeons classified 21 (42%) as having "poor bone" quality through a negative thumb test. High-risk patients had a negative thumb test 33.8% (23/68) and 37.1% (26/71) of the time for HU and FRAX, respectively. Conclusions: Surgeons are poor at identifying suboptimal bone quality at the anatomic neck of the proximal humerus based on intraoperative thumb test when referencing against CT HU and FRAX scores. The objective measures of CT HU and FRAX scoring may be useful metrics to incorporate into surgeons' preoperative plans for humeral stem fixation using readily available imaging and demographic data.

Adapting and Testing the Care Partner Hospital Assessment Tool for Use in Dementia Care: Protocol for a 2 Sequential Phase Study.

BACKGROUND: Research and policy demonstrate the value of and need for systematically identifying and preparing care partners for their caregiving responsibilities while their family member or friend living with dementia is hospitalized. The Care Partner Hospital Assessment Tool (CHAT) has undergone content and face validation and has been endorsed as appropriate by clinicians to facilitate the timely identification and preparation of care partners of older adult patients during their hospitalization. However, the CHAT has not yet been adapted or prospectively evaluated for use with care partners of hospitalized people living with dementia. Adapting and testing the CHAT via a pilot study will provide the necessary evidence to optimize feasibility and enable future efficacy trials. OBJECTIVE: The purpose of this paper is to describe the study protocol for the adaptation and testing of the CHAT for use among care partners of hospitalized people living with dementia to better prepare them for their caregiving responsibilities after hospital discharge. METHODS: Our protocol is based on the National Institutes of Health Stage Model and consists of 2 sequential phases, including formative research and the main trial. In phase 1, we will use a participatory human-centered design process that incorporates people living with dementia and their care partners, health care administrators, and clinicians to adapt the CHAT for dementia care (ie, the Dementia CHAT [D-CHAT]; stage IA). In phase 2, we will partner with a large academic medical system to complete a pilot randomized controlled trial to examine the feasibility and estimate the size of the effect of the D-CHAT on care partners' preparedness for caregiving (stage IB). We anticipate this study to take approximately 60 months to complete, from study start-up procedures to dissemination. The 2 phases will take place between December 1, 2022, and November 30, 2027. RESULTS: The study protocol will yield (1) a converged-upon, ready-for-feasibility testing D-CHAT; (2) descriptive and feasibility characteristics of delivering the D-CHAT; and (3) effect size estimates of the D-CHAT on care partner preparedness. We anticipate that the resultant D-CHAT will provide clinicians with guidance on how to identify and better prepare care partners for hospitalized people living with dementia. In turn, care partners will feel equipped to fulfill caregiving roles for their family members or friends living with dementia. CONCLUSIONS: The expected results of this study are to favorably impact hospital-based care processes and outcomes for people living with dementia and their care partners and to elucidate the essential caregiving role that so many care partners of people living with dementia assume. TRIAL REGISTRATION: ClinicalTrials.gov NCT05592366; https://clinicaltrials.gov/ct2/show/NCT05592366. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/46808.

Radiographic Comparison of Virtual Surgical Corrective Options for Excessive Tibial Plateau Angle in the Dog.

OBJECTIVE: The main aim of this study is to compare the impact of six proximal tibial osteotomies on the geometry and alignment of tibias with and without excessive tibial plateau angle (TPA). STUDY DESIGN: Mediolateral radiographs of 30 canine tibias were divided into three groups (n = 10/group): moderate TPA (≤34 degrees), severe TPA (34.1-44 degrees) and extreme TPA (>44 degrees). Six proximal tibial osteotomies were simulated on each tibia using orthopaedic planning software: cranial closing wedge ostectomy (CCWO), modified CCWO (mCCWO), isosceles CCWO (iCCWO), neutral isosceles CCWO (niCCWO), tibial plateau levelling osteotomy with CCWO (TPLO/CCWO) and coplanar centre of rotation of angulation-based levelling osteotomy (coCBLO). All tibias were reduced to a standard target TPA. Pre- and postoperative measurements were obtained for each virtual correction. Compared outcome measures included tibial long axis shift (TLAS), cranial tibial tuberosity shift (cTTS), distal tibial tuberosity shift (dTTS), tibial shortening and osteotomy overlap. RESULTS: Across all TPA groups, TPLO/CCWO had the lowest mean TLAS (1.4 mm) and dTTS (6.8 mm); coCBLO had the largest TLAS (6.5 mm) and cTTS (13.1 mm); CCWO had the largest dTTS (29.5 mm). CCWO had the largest degree of tibial shortening of 6.5 mm, while mCCWO, niCCWO and coCBLO resulted in minimal tibial lengthening (1.8-3.0 mm). These trends were generally conserved across different TPA groups. All findings had a p-value less than 0.05. CONCLUSION: mCCWO balances moderate alterations to tibial geometry while preserving osteotomy overlap. The TPLO/CCWO has the least effect on tibial morphology alteration, whereas the coCBLO results in the largest alteration.

Accuracy of pin placement in the canine thoracolumbar spine using a free-hand probing technique versus 3D-printed patient-specific drill guides: An ex-vivo study.

OBJECTIVE: To compare pin placement accuracy, intraoperative technique deviations, and duration of pin placement for pins placed by free-hand probing (FHP) or 3D-printed drill guide (3DPG) technique. SAMPLE POPULATION: Four greyhound cadavers. METHODS: Computed tomography (CT) examinations from T6-sacrum were obtained for determination of optimal pin placement and 3DPG creation. Two 3.2/2.4-mm positive profile pins were inserted per vertebra, one left and one right from T7-L7 (FHP [n = 56]; 3DPG [n = 56]) by one surgeon and removed for repeat CT. Duration of pin placement and intraoperative deviations (unanticipated deviations from planned technique) were recorded. Pin tracts were graded by two blinded observers using modified Zdichavsky classification. Descriptive statistics were used. RESULTS: A total of 54/56 pins placed with 3DPGs were assigned grade I (optimal placement) compared with 49/56 pins using the FHP technique. A total of 2/56 pins placed with 3DPGs and 3/56 pins using the FHP technique were assigned grade IIa (partial medial violation). A total of 4/56 pins placed using the FHP technique were assigned grade IIIa (partial lateral violation). No pins were assigned grade IIb (full medial violation). Intraoperative technique deviations occurred with 6/56 pins placed using the FHP technique and no pins with 3DPGs. Overall, pins were placed faster (mean ± SD 2.6 [1.3] vs. 4.5 [1.8] min) with 3DPGs. CONCLUSIONS: Both techniques were accurate for placement of spinal fixation pins. The 3DPG technique may decrease intraoperative deviations and duration of pin placement. CLINICAL RELEVANCE: Both techniques allow accurate pin placement in the canine thoracolumbar spine. The FHP technique requires specific training and has learning curve, whereas 3DPG technique requires specific software and 3D printers.

Intraoperative physician assessment of bone: correlation to bone mineral density.

This study evaluated the intraoperative physician assessment (IPA) of bone status at time of total knee arthroplasty. IPA was highly correlated with distal femur and overall bone mineral density. When IPA identifies poor bone status, formal bone health assessment is indicated. PURPOSE: Intuitively, intraoperative physician assessment (IPA) would be an excellent measure of bone status gained through haptic feedback during bone preparation. However, no studies have evaluated the orthopedic surgeon's ability to do so. This study's purpose, in patients undergoing total knee arthroplasty (TKA), was to relate IPA with (1) the lowest bone mineral density (BMD) T-score at routine clinical sites; and (2) with distal femur BMD. METHODS: Seventy patients undergoing TKA by 3 surgeons received pre-operative DXA. Intraoperatively, bone quality was assessed on a 5-point scale (1 excellent to 5 poor) based on tactile feedback to preparation. Demographic data, DXA results, and IPA score between surgeons were compared by factorial ANOVA. Lowest T-score and distal femur BMD were associated with IPA using Spearman's correlation. RESULTS: The mean (SD) age and BMI were 65.8 (7.6) years and 31.4 (5.1) kg/m2, respectively. Patient demographic data, BMD, and IPA (mean [SD] = 2.74 [1.2]) did not differ between surgeons. IPA correlated with the lowest T-score (R = 0.511) and distal femur BMD (R = 0.603-0.661). Based on the lowest T-score, no osteoporotic patients had an IPA above average, and none with normal BMD was classified as having poor bone. CONCLUSIONS: IPA is highly correlated with local (distal femur) and overall BMD. This study supports the International Society for Clinical Densitometry position that surgeon concern regarding bone quality should lead to bone health assessment. As IPA is comparable between surgeons, it is logical this can be widely applied by experienced orthopedic surgeons. Future studies evaluating IPA at other anatomic sites are indicated.

Mortality Rates After Nonoperative Geriatric Hip Fracture Treatment: A Matched Cohort Analysis.

OBJECTIVE: To compare the mortality rate between geriatric patients with hip fracture treated nonoperatively and a matched cohort treated operatively. DESIGN: Retrospective Observational Matched Cohort Study. SETTING: Academic Level 1 Trauma Center. PATIENTS: Geriatric patients who sustained femoral neck and intertrochanteric/peritrochanteric fractures, excluding isolated greater trochanteric fractures. All patients older than 65 years with hip fractures over a 10-year period were identified. Operative patients were matched at a 2:1 ratio, when possible, to nonoperative patients based on Charlson Comorbidity Index and American Society of Anesthesiologists score. INTERVENTION: Nonoperative treatment or operative treatment (femoral neck fractures: cannulated screw fixation or hemiarthroplasty; intertrochanteric/peritrochanteric fractures: sliding hip screw or cephalomedullary nail fixation; or proximal femoral locking plate). MAIN OUTCOMES: Mortality calculated at 30 and 90 days, and 1-year after injury. Mortality was compared between groups using logistic regression while controlling for age, CVA/TIA, and dementia. RESULTS: Seven hundred seventy-two patients (171 nonoperative and 601 operative) were initially identified. After applying the matching algorithm, 128 nonoperative and 239 operative patients were included in the analysis. There were no significant differences in age, sex, Charlson Comorbidity Index, or American Society of Anesthesiologists score between the cohorts. Nonoperative patients had a significantly higher 1-year mortality rate than operative patients [46.1% vs. 18.0%, Odds Ratio (95% confidence interval): 3.85 (2.34-6.41), P < 0.001]. CONCLUSIONS: Geriatric patients with hip fracture treated nonoperatively had a 1-year mortality rate of 46.1%, more than double the rate among operative patients. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Correlation of mineral density and elastic modulus of dog dentin using µ-CT and nanoindentation.

This study sought to 1) investigate the spatial distribution of mineral density of dog dentin using µ-CT and 2) characterize the relationship between the elastic modulus and mineral density of dog dentin using nanoindentation and µ-CT. Maxillary canine teeth of 10 mature dogs were scanned with a µ-CT then sectioned in the transverse and vertical planes and tested using nanoindentation. Spatial distribution of mineral density and elastic modulus was quantified. Results demonstrated significant spatial variation in mineral density and elastic modulus. Mineral density and elastic modulus generally increased from the dentin-pulp interface to the dentino-enamel junction and from the crown base to the crown tip. Significant site dependent correlations between mineral density and elastic modulus were determined (0.021 > R2 > 0.408). The results of this study suggest that while mineral density is a mediator of elastic modulus, other mediators such as collagen content may contribute to the mechanical behavior of dog dentin.