Diffusion MRI Metrics Characterize Postoperative Clinical Outcomes After Surgery for Cervical Spondylotic Myelopathy.

BACKGROUND AND OBJECTIVES: Advanced diffusion-weighted MRI (DWI) modeling, such as diffusion tensor imaging (DTI) and diffusion basis spectrum imaging (DBSI), may help guide rehabilitation strategies after surgical decompression for cervical spondylotic myelopathy (CSM). Currently, however, postoperative DWI is difficult to interpret, owing to signal distortions from spinal instrumentation. Therefore, we examined the relationship between postoperative DTI/DBSI-extracted from the rostral C3 spinal level-and clinical outcome measures at 2-year follow-up after decompressive surgery for CSM. METHODS: Fifty patients with CSM underwent complete clinical and DWI evaluation-followed by DTI/DBSI analysis-at baseline and 2-year follow-up. Clinical outcomes included the modified Japanese Orthopedic Association score and comprehensive patient-reported outcomes. DTI metrics included apparent diffusion coefficient, fractional anisotropy, axial diffusivity, and radial diffusivity. DBSI metrics evaluated white matter tracts through fractional anisotropy, fiber fraction, axial diffusivity, and radial diffusivity as well as extra-axonal pathology through restricted and nonrestricted fraction. Cross-sectional Spearman's correlations were used to compare postoperative DTI/DBSI metrics with clinical outcomes. RESULTS: Twenty-seven patients with CSM, including 15, 7, and 5 with mild, moderate, and severe disease, respectively, possessed complete baseline and postoperative DWI scans. At 2-year follow-up, there were 10 significant correlations among postoperative DBSI metrics and postoperative clinical outcomes compared with 3 among postoperative DTI metrics. Of the 13 significant correlations, 7 involved the neck disability index (NDI). The strongest relationships were between DBSI axial diffusivity and NDI (r = 0.60, P < .001), DBSI fiber fraction and NDI (rs = -0.58, P < .001), and DBSI restricted fraction and NDI (rs = 0.56, P < .001). The weakest correlation was between DTI apparent diffusion coefficient and NDI (r = 0.35, P = .02). CONCLUSION: Quantitative measures of spinal cord microstructure after surgery correlate with postoperative neurofunctional status, quality of life, and pain/disability at 2 years after decompressive surgery for CSM. In particular, DBSI metrics may serve as meaningful biomarkers for postoperative disease severity for patients with CSM.

C1-2 hypermobility and its impact on the spinal cord: a finite element analysis.

OBJECTIVE: The authors present a finite element analysis (FEA) evaluating the mechanical impact of C1-2 hypermobility on the spinal cord. METHODS: The Code_Aster program was used to perform an FEA to determine the mechanical impact of C1-2 hypermobility on the spinal cord. Normative values of Young's modulus were applied to the various components of the model, including bone, ligaments, and gray and white matter. Two models were created: 25° and 50° of C1-on-C2 rotation, and 2.5 and 5 mm of C1-on-C2 lateral translation. Maximum von Mises stress (VMS) throughout the cervicomedullary junction was calculated and analyzed. RESULTS: The FEA model of 2.5 mm lateral translation of C1 on C2 revealed maximum VMS for gray and white matter of 0.041 and 0.097 MPa, respectively. In the 5-mm translation model, the maximum VMS for gray and white matter was 0.069 and 0.162 MPa. The FEA model of 25° of C1-on-C2 rotation revealed maximum VMS for gray and white matter of 0.052 and 0.123 MPa. In the 50° rotation model, the maximum VMS for gray and white matter was 0.113 and 0.264 MPa. CONCLUSIONS: This FEA revealed significant spinal cord stress during pathological rotation (50°) and lateral translation (5 mm) consistent with values found during severe spinal cord compression and in patients with myelopathy. While this finite element model requires oversimplification of the atlantoaxial joint, the study provides biomechanical evidence that hypermobility within the C1-2 joint leads to pathological spinal cord stress.

Radiographic Alignment Parameters for Lumbosacral Reconstruction in Patients With Altered S1 Morphology.

STUDY DESIGN: Retrospective quantitative analysis study. OBJECTIVES: Pelvic incidence has been established as central radiographic marker which determines patient-specific correction goals during surgery for adult spinal deformity. In cases with sacral doming or sacral osteotomy where the PI cannot be calculated, reliable radiographic parameters need to be established to determine surgical goals. We aim to determine multiple radiographic parameters and formulas that can be utilized when the S1 superior endplate is obscured. METHODS: Retrospective analysis was performed on 68 healthy volunteers without prior spine surgery with full-length radiographs. Pelvic incidence, sacral slope, and pelvic tilt were calculated for each patient. Additional measurements such as L4, L5, and S2 incidence, tilt, and slope were collected. A new radiographic parameter defined as the L4-Sciatic notch angle was measured. Regression analysis was performed on each value to determine its relationship with S1 based incidence, tilt, and slope. RESULTS: Mean values for L5 incidence, L4 incidence, and L4 sciatic notch angle were 21.8° ± 8.9, 4.4° ± 8.1, and 44.4° ± 12, respectively. The linear regression analysis produced the following formulas which can be utilized to determine deformity correction goals when pelvic incidence can be calculated pre-operatively: L5i = .65*S1i-11.4, L4i = .44*S1i-18.6, and L4SNA = -.34*S1i + 66.5. In settings where pelvic incidence cannot be calculated, the following formulas can be utilized: L5i = .66*S2i-32.3 and L4SNA = -.02*S2i2 + 1.1*S2i + 63.5. P-values for all regression analyses were <.001. CONCLUSION: This study provides target radiographic alignment values that can be utilized for patients with either pre-operative altered S1 endplates or in cases with intraoperative alteration of S1 (sacral osteotomy).

Faculty and Resident Perspectives on the Implementation of Entrustable Professional Activities in General Surgery Residency.

OBJECTIVE: This study aimed to identify what best practices facilitate implementation of Entrustable Professional Activities (EPAs) into surgical training programs. DESIGN: This is a mixed methods study utilizing both survey data as well as semi-structured interviews of faculty and residents involved in the American Board of Surgery (ABS) EPA pilot study. SETTING: From 2018 to 2020, the ABS conducted a pilot that introduced five EPAs across 28 general surgery training programs. PARTICIPANTS: All faculty members and residents at the 28 pilot programs were invited to participate in the study. RESULTS: About 117 faculty members and 79 residents responded to the survey. The majority of faculty (81%) and residents (66%) felt that EPAs were useful and were a valuable addition to training. While neither group felt that EPAs were overly time consuming to complete, residents did report difficulty incorporating them into their daily workflow (44%). Semi-structured interviews found that programs that focused on faculty and resident -development and utilized frequent reminders about the importance and necessity of EPAs tended to perform better. CONCLUSIONS: EPA implementation is feasible in general surgery training programs but requires significant effort and engagement from all levels of program personnel. As EPAs are implemented by the ABS nationally a focus on resident and faculty development will be critical to success.

Modified S1 Pedicle Subtraction Osteotomy.

STUDY DESIGN: Surgical technique video. OBJECTIVE: To report a surgical technique to revise patients with previous fusions at L4-S1 leading to an iatrogenic flat back and sagittal imbalance using L5-S1 transforaminal interbody fusion combined with a small S1 corner osteotomy. BACKGROUND: This is a case of a woman (51 y old) with a history of multiple lumbar surgeries, severe back pain, sagittal imbalance, and loss of lordosis. METHODS: We describe a feasible revision technique in a complex patient with the goal of attaining optimal distribution of lumbar lordosis and sagittal balance through a modified S1 pedicle subtraction osteotomy, and the use of an interbody cage to enhance the fusion rate and facilitate closure of the 3-column osteotomy. RESULTS: The preoperative patient lordosis angle of 31 degrees at L1-L4 and 16 degrees at L4-S1 became 12 degrees at L1-L4 and 44 degrees at L4-S1 postoperatively. CONCLUSION: The combination of L5-S1 transforaminal interbody fusion and S1 corner osteotomy is a feasible technique for the restoration of lumbar lordosis in patients with previous fusion and consequent loss of lordosis.

Roles, Responsibilities, and Expectations of Medical Students on Surgical Subinternships: A Modified Delphi Consensus Study.

PURPOSE: Surgical subinternships are important rotations for students preparing for a career in general surgery; however, these rotations often vary by institution and service. This modified Delphi study was conducted to reach a consensus set of roles, responsibilities, and expectations of fourth-year medical students on their surgical subinternships. METHOD: Candidate statements on roles, responsibilities, and expectations of subinterns were categorized into 7 domains: rotation structure, rounding and patient care, operating room conduct, technical skills, knowledge base, clinic, and professionalism. Expert panels were assembled of key stakeholders: program directors, clerkship directors, other education faculty, trainees, and recent subinterns. Three Delphi rounds were conducted from January to April 2023 to reach consensus defined a priori as a Cronbach α ≥ 0.8 and 80% or greater panel agreement. RESULTS: Forty-six expert panelists were recruited to participate in Delphi rounds, with 100%, 95.7%, and 97.8% response rates in the first, second, and third rounds, respectively. By the third round, 67 statements reached consensus as essential roles, responsibilities, and expectations of surgical subinterns. Key themes from these 67 statements included subinterns approximating the role of an intern with respect to work hours, patient care responsibilities, basic technical skills, and knowledge base. Panelists rated rounding and patient care as the most important domain, followed closely by professionalism. Additional key domains for evaluation in descending order were knowledge base, operating room conduct, clinic, and technical skills. By the third round, notable disagreements in the Delphi process included technical skills and rounding and patient care (93.3% and 88.9% agreement, respectively). CONCLUSIONS: This study provides a national consensus on core roles, responsibilities, and expectations for medical students completing surgical subinternships. Students can use these recommendations to prepare for subinternships, whereas faculty as well as residents and fellows can use them to evaluate applicants for general surgery residency positions.

Preoperative Mobile Health Data Improve Predictions of Recovery From Lumbar Spine Surgery.

BACKGROUND AND OBJECTIVES: Neurosurgeons and hospitals devote tremendous resources to improving recovery from lumbar spine surgery. Current efforts to predict surgical recovery rely on one-time patient report and health record information. However, longitudinal mobile health (mHealth) assessments integrating symptom dynamics from ecological momentary assessment (EMA) and wearable biometric data may capture important influences on recovery. Our objective was to evaluate whether a preoperative mHealth assessment integrating EMA with Fitbit monitoring improved predictions of spine surgery recovery. METHODS: Patients age 21-85 years undergoing lumbar surgery for degenerative disease between 2021 and 2023 were recruited. For up to 3 weeks preoperatively, participants completed EMAs up to 5 times daily asking about momentary pain, disability, depression, and catastrophizing. At the same time, they were passively monitored using Fitbit trackers. Study outcomes were good/excellent recovery on the Quality of Recovery-15 (QOR-15) and a clinically important change in Patient-Reported Outcomes Measurement Information System Pain Interference 1 month postoperatively. After feature engineering, several machine learning prediction models were tested. Prediction performance was measured using the c-statistic. RESULTS: A total of 133 participants were included, with a median (IQR) age of 62 (53, 68) years, and 56% were female. The median (IQR) number of preoperative EMAs completed was 78 (61, 95), and the median (IQR) number of days with usable Fitbit data was 17 (12, 21). 63 patients (48%) achieved a clinically meaningful improvement in Patient-Reported Outcomes Measurement Information System pain interference. Compared with traditional evaluations alone, mHealth evaluations led to a 34% improvement in predictions for pain interference (c = 0.82 vs c = 0.61). 49 patients (40%) had a good or excellent recovery based on the QOR-15. Including preoperative mHealth data led to a 30% improvement in predictions of QOR-15 (c = 0.70 vs c = 0.54). CONCLUSION: Multimodal mHealth evaluations improve predictions of lumbar surgery outcomes. These methods may be useful for informing patient selection and perioperative recovery strategies.

T1 Pedicle Subtraction Osteotomy With Subaxial Cervical Pedicle Screw Fixation.

Patients suffering from ankylosing spondylitis are not only predisposed to the development of rigid cervicothoracic deformities but are also at an increased risk of cervical fractures. Deformity correction and stabilization are particularly challenging in this patient population due to the brittle bone quality and low bone mineral density. Thoracic pedicle subtraction osteotomy is a workhorse approach for the correction of focal severe kyphotic deformity with lower complication rates than 3-column osteotomy. Successful execution of an upper thoracic PSO requires careful presurgical planning as well as anticipation of the patient's postoperative needs. Here, we describe the use of a T1 PSO in the correction of a rigid cervicothoracic chin-on-chest deformity in a patient with AS. The risk of implant failure was reduced by the use of a multi-rod construct, navigated cervical pedicle screws, and dual-pitched thoracic pedicle screws.

Annual mpMRI surveillance: PI-RADS upgrading and increasing trend correlated with patients who harbor clinically significant disease.

INTRODUCTION: Prostate cancer screening has routinely identified men with very low- or low-risk disease, per the National Comprehensive Cancer Network guidelines. Current literature has demonstrated that the most appropriate management strategy for these patients is active surveillance (AS). The mainstay of AS includes periodic biopsies and biannual prostate-specific antigen tests. However, multiparametric magnetic resonance imaging (mpMRI) is uniquely posed to improve patient surveillance. This study aimed to evaluate the utility of an annual mpMRI in patients on AS, focusing on radiologic upgrading and Prostate Imaging-Reporting and Data System (PI-RADS) trends as indicators of clinically significant disease. METHODS: This prospective, single intuition, study enrolled 208 patients on AS who had at least two biopsies and 1 mpMRI with a median follow-up of 5.03 years. The main outcome variable was time to Gleason grade (GG) reclassification. RESULTS: After delineating patients on their initial PI-RADS score, men with score 3 and 5 lesions at first MRI had comparable GG reclassification-free survival to their counterparts. Conversely, men with initial PI-RADS 4 lesions showed a lower 5-year GG reclassification-free survival compared to those with PI-RADS score 1-2. The cohort was then subset to 70 patients who obtained ≥2 mpMRIs on protocol. Men experiencing uptrending mpMRI scores had an increased risk of GG reclassification, with a 35.4% difference in 5 year GG reclassification-free survival probability on the Kaplan-Meier curve analysis. CONCLUSION: In conclusion, this study demonstrates that for men on AS with stable recapitulated disease, an annual MRI may replace repeat biopsies after confirmatory sampling has been obtained. On the other hand, men who initiate AS with PI-RADS 4 and/or who display uptrending mpMRI scores require periodic biopsies along with repeat imaging. This study highlights the utility of integrating an annual MRI into AS protocols, thus promising a more effective approach to management.

Implications of Preoperative Depression for Lumbar Spine Surgery Outcomes: A Systematic Review and Meta-Analysis.

Importance: Comorbid depression is common among patients with degenerative lumbar spine disease. Although a well-researched topic, the evidence of the role of depression in spine surgery outcomes remains inconclusive. Objective: To investigate the association between preoperative depression and patient-reported outcome measures (PROMs) after lumbar spine surgery. Data Sources: A systematic search of PubMed, Cochrane Database of Systematic Reviews, Embase, Scopus, PsychInfo, Web of Science, and ClinicalTrials.gov was performed from database inception to September 14, 2023. Study Selection: Included studies involved adults undergoing lumbar spine surgery and compared PROMs in patients with vs those without depression. Studies evaluating the correlation between preoperative depression and disease severity were also included. Data Extraction and Synthesis: All data were independently extracted by 2 authors and independently verified by a third author. Study quality was assessed using Newcastle-Ottawa Scale. Random-effects meta-analysis was used to synthesize data, and I2 was used to assess heterogeneity. Metaregression was performed to identify factors explaining the heterogeneity. Main Outcomes and Measures: The primary outcome was the standardized mean difference (SMD) of change from preoperative baseline to postoperative follow-up in PROMs of disability, pain, and physical function for patients with vs without depression. Secondary outcomes were preoperative and postoperative differences in absolute disease severity for these 2 patient populations. Results: Of the 8459 articles identified, 44 were included in the analysis. These studies involved 21 452 patients with a mean (SD) age of 57 (8) years and included 11 747 females (55%). Among these studies, the median (range) follow-up duration was 12 (6-120) months. The pooled estimates of disability, pain, and physical function showed that patients with depression experienced a greater magnitude of improvement compared with patients without depression, but this difference was not significant (SMD, 0.04 [95% CI, -0.02 to 0.10]; I2 = 75%; P = .21). Nonetheless, patients with depression presented with worse preoperative disease severity in disability, pain, and physical function (SMD, -0.52 [95% CI, -0.62 to -0.41]; I2 = 89%; P < .001), which remained worse postoperatively (SMD, -0.52 [95% CI, -0.75 to -0.28]; I2 = 98%; P < .001). There was no significant correlation between depression severity and the primary outcome. A multivariable metaregression analysis suggested that age, sex (male to female ratio), percentage of comorbidities, and follow-up attrition were significant sources of variance. Conclusions and Relevance: Results of this systematic review and meta-analysis suggested that, although patients with depression had worse disease severity both before and after surgery compared with patients without depression, they had significant potential for recovery in disability, pain, and physical function. Further investigations are needed to examine the association between spine-related disability and depression as well as the role of perioperative mental health treatments.

Impact of Upper Limb Motor Recovery on Functional Independence After Traumatic Low Cervical Spinal Cord Injury.

Cervical spinal cord injury (SCI) causes devastating loss of upper limb function and independence. Restoration of upper limb function can have a profound impact on independence and quality of life. In low-cervical SCI (level C5-C8), upper limb function can be restored via reinnervation strategies such as nerve transfer surgery. The translation of recovered upper limb motor function into functional independence in activities of daily living (ADLs), however, remains unknown in low cervical SCI (i.e., tetraplegia). The objective of this study was to evaluate the association of patterns in upper limb motor recovery with functional independence in ADLs. This will then inform prioritization of reinnervation strategies focused to maximize function in patients with tetraplegia. This retrospective study performed a secondary analysis of patients with low cervical (C5-C8) enrolled in the SCI Model Systems (SCIMS) database. Baseline neurological examinations and their association with functional independence in major ADLs-i.e., eating, bladder management, and transfers (bed/wheelchair/chair)-were evaluated. Motor functional recovery was defined as achieving motor strength, in modified research council (MRC) grade, of ≥ 3 /5 at one year from ≤ 2/5 at baseline. The association of motor function recovery with functional independence at one-year follow-up was compared in patients with recovered elbow flexion (C5), wrist extension (C6), elbow extension (C7), and finger flexion (C8). A multi-variable logistic regression analysis, adjusting for known factors influencing recovery after SCI, was performed to evaluate the impact of motor function at one year on a composite outcome of functional independence in major ADLs. Composite outcome was defined as functional independence measure score of 6 or higher (complete independence) in at least two domains among eating, bladder management, and transfers. Between 1992 and 2016, 1090 patients with low cervical SCI and complete neurological/functional measures were included. At baseline, 67% of patients had complete SCI and 33% had incomplete SCI. The majority of patients were dependent in eating, bladder management, and transfers. At one-year follow-up, the largest proportion of patients who recovered motor function in finger flexion (C8) and elbow extension (C7) gained independence in eating, bladder management, and transfers. In multi-variable analysis, patients who had recovered finger flexion (C8) or elbow extension (C7) had higher odds of gaining independence in a composite of major ADLs (odds ratio [OR] = 3.13 and OR = 2.87, respectively, p < 0.001). Age 60 years (OR = 0.44, p = 0.01), and complete SCI (OR = 0.43, p = 0.002) were associated with reduced odds of gaining independence in ADLs. After cervical SCI, finger flexion (C8) and elbow extension (C7) recovery translate into greater independence in eating, bladder management, and transfers. These results can be used to design individualized reinnervation plans to reanimate upper limb function and maximize independence in patients with low cervical SCI.

Risk factors for infection and acute urinary retention following transperineal prostate biopsy.

PURPOSE: To calculate the frequency of infection and acute urinary retention (AUR) following transperineal (TP) prostate biopsy at a single high-volume academic institution and determine risk factors for developing these post-biopsy conditions. METHODS: Men undergoing TP prostate biopsy from 2012 to 2022 at our institution were retrospectively identified and chart reviewed. TP biopsies were performed with TR ultrasound (TRUS) guidance with anesthesia using a brachytherapy grid template. TRUS volumes were recorded during the procedure, and magnetic resonance imaging (MRI) volumes were calculated using the ellipsoid formula. When available, MRI volume was used for all analysis, and when absent, TRUS volume was used. AUR was defined as requiring urinary catheter placement within 72 h post-biopsy for inability to urinate. Univariable analysis was performed and variables with p < 0.1 and/or established clinical relevance were included in a backward binary logistic regression to produce an optimized model that fit the data without collinearity between variables. RESULTS: A total of 767 TP biopsies were completed in the study window. The frequency of infection was 1.83% (N = 14/767). The total frequency of AUR was 5.48% (N = 42/767). On multivariable regression, patients who went into AUR were five times as likely to develop infection (p = 0.020). Patients with infection post-TP biopsy were four times as likely to develop AUR (p = 0.047) and with prostates > 61.21 cc were three times as likely (p = 0.019). CONCLUSION: According to our model, AUR is the greatest risk factor for infection post-TP biopsy. With regard to AUR risks, infection post-biopsy and prostate size > 61.21 cc are the greatest risk factors.

Clomiphene Citrate in the Management of Infertility in Oligospermic Obese Men with Hypogonadism: Retrospective Pilot Study.

Background and Objectives: Obesity is a significant risk factor for hypogonadism and infertility that is further associated with reduced semen quality. The aim of this study is to evaluate the effect of clomiphene citrate (CC), prescribed for treating infertility, on serum testosterone and semen parameters, particularly in oligospermic obese hypogonadal men. Materials and Methods: A retrospective analysis of data related to men (n = 53) who underwent CC treatment for infertility and hypogonadism (testosterone < 300 ng/dL) was performed. Patients with obesity (BMI ≥ 30 kg/m2) and sperm concentration ≤ 15 × 106/mL were included for analysis. Results: The overall results showed that, in oligospermic obese men (n = 31), treatment with CC significantly improved baseline sperm concentration (4.5 ± 6.8 × 106/mL vs. 11.4 ± 15.5 × 106/mL, p < 0.05) and motility (31.5% ± 21.5% vs. 42.6% ± 14.7%, p < 0.05). Furthermore, subsequent examination of oligospermic hypogonadal obese men treated with CC (n = 13) revealed substantial improvements in baseline serum testosterone levels (193.8 ± 59.3 ng/dL vs. 332.7 ± 114.8 ng/dL, p < 0.05) along with an increase in sperm concentration, total motility, and normal morphology. Conclusions: The results of this retrospective study suggest that CC treatment not only improves chances of fertility outcomes by substantially improving semen parameters but also increases total serum testosterone levels in oligospermic obese men without any supplemental and expensive testosterone replacement therapy.

Feasibility of postoperative diffusion-weighted imaging to assess representations of spinal cord microstructure in cervical spondylotic myelopathy.

OBJECTIVE: Diffusion basis spectrum imaging (DBSI) has shown promise in evaluating cervical spinal cord structural changes in patients with cervical spondylotic myelopathy (CSM). DBSI may also be valuable in the postoperative setting by serially tracking spinal cord microstructural changes following decompressive cervical spine surgery. Currently, there is a paucity of studies investigating this topic, likely because of challenges in resolving signal distortions from spinal instrumentation. Therefore, the objective of this study was to assess the feasibility of DBSI metrics extracted from the C3 spinal level to evaluate CSM patients postoperatively. METHODS: Fifty CSM patients and 20 healthy controls were enrolled in a single-center prospective study between 2018 and 2020. All patients and healthy controls underwent preoperative and postoperative diffusion-weighted MRI (dMRI) at a 2-year follow-up. All CSM patients underwent decompressive cervical surgery. The modified Japanese Orthopaedic Association (mJOA) score was used to categorize CSM patients as having mild, moderate, or severe myelopathy. DBSI metrics were extracted from the C3 spinal cord level to minimize image artifact and reduce partial volume effects. DBSI anisotropic tensors evaluated white matter tracts through fractional anisotropy, axial diffusivity, radial diffusivity, and fiber fraction. DBSI isotropic tensors assessed extra-axonal pathology through restricted and nonrestricted fractions. RESULTS: Of the 50 CSM patients, both baseline and postoperative dMR images with sufficient quality for analysis were obtained in 27 patients. These included 15 patients with mild CSM (mJOA scores 15-17), 7 with moderate CSM (scores 12-14), and 5 with severe CSM (scores 0-11), who were followed up for a mean of 23.5 (SD 4.1, range 11-31) months. All preoperative C3-level DBSI measures were significantly different between CSM patients and healthy controls (p < 0.05), except DBSI fractional anisotropy (p = 0.31). At the 2-year follow-up, the same significance pattern was found between CSM patients and healthy controls, except DBSI radial diffusivity was no longer statistically significant (p = 0.75). When assessing change (i.e., postoperative - preoperative values) in C3-level DBSI measures, CSM patients exhibited significant decreases in DBSI radial diffusivity (p = 0.02), suggesting improvement in myelin integrity (i.e., remyelination) at the 2-year follow-up. Among healthy controls, there was no significant difference in DBSI metrics over time. CONCLUSIONS: DBSI metrics derived from dMRI at the C3 spinal level can be used to provide meaningful insights into representations of the spinal cord microstructure of CSM patients at baseline and 2-year follow-up. DBSI may have the potential to characterize white matter tract recovery and inform outcomes following decompressive cervical surgery for CSM.

Molecular mechanisms of penile traction for penile rehabilitation in a bilateral cavernous nerve crush injury rat model.

Background: Prostate cancer is the most common solid-organ malignancy in adult men. Early detection and treatment of prostate cancer with radical prostatectomy (RP) has improved cancer-specific survival but is associated with penile shortening and erectile dysfunction. Penile traction therapy (PTT) has been demonstrated to increase stretched penile length (SPL) prior to penile prosthesis placement and may improve erectile function (EF) in patients with Peyronie's disease. We aimed to evaluate the efficacy of PTT in preserving penile length and EF after bilateral cavernous nerve crush injury (BCNI) in a rat model. Methods: Twenty-four male Sprague-Dawley rats aged 11-13 weeks were randomly assigned to three groups (n=8, each): sham operation with no PTT (Sham), BCNI without PTT (Crush), and BCNI with PTT (Traction). PTT was started on postoperative day 3. A traction force of 1 Newton was applied to the penis for 30 minutes each day for 28 days. After 28 days of traction, the cavernous nerve was stimulated while recording the intracavernosal pressure (ICP) and the mean arterial pressure (MAP) simultaneously. Cavernosal tissue was excised, and western blot analysis for endothelial nitric oxide synthase (eNOS) was performed. Significance was determined by using ANOVA with Tukey-Kruger post-hoc testing. Results: At 4 weeks after nerve injury, the Traction group had significantly greater SPL compared to the Sham and Crush groups (30 vs. 28 and 27 mm, respectively). The Sham group had significantly greater EF (ΔICP/MAP) compared to the Crush group at 2.5, 5, and 7.5 V. The EF of the Traction group was between that of the Sham and Crush groups and was not significantly different from the Sham group at any voltages. Further downstream analysis revealed that the Traction group had significantly greater eNOS expression in cavernosal tissue compared to the Crush group, which was confirmed on western blot analysis and immunohistochemistry (IHC) staining. Conclusions: Findings from this animal study suggest that PTT has the potential to mitigate penile retraction after RP. While more studies are needed to determine the effect of PTT on preservation of EF, the increased eNOS expression observed in the Traction group offers a potential protective mechanism of action.

Less is more: single dose versus extended antibiotic prophylaxis for transperineal prostate biopsy.

INTRODUCTION: There is an ongoing debate as to the appropriate regimen of antibiotic prophylaxis with transperineal (TP) biopsy. The objective of this study was to report the rate of infection following TP biopsy at a high-volume institution and assess the impact of single dose antibiotics at the time of biopsy versus outpatient antibiotics in preventing postprocedural infections. MATERIALS AND METHODS: Records of men undergoing TP prostate biopsy from 2012 to 2022 were reviewed. Patients were divided into two groups, those who received single dose intravenous (IV) antibiotics at the time of biopsy (n = 440) and those who received both IV antibiotics at the time of biopsy and outpatient antibiotics before/after biopsy (n = 327). Post biopsy infection was defined as at least one of the following: fever (≥ 38.3°C) with/without symptoms of urinary tract infection or positive urine culture (> 105 colony forming units) within 72 hours post biopsy. The rates of infection were compared between the two groups. RESULTS: A total of 767 biopsies were included in the study. Infection rate post TP biopsy was 1.83% (n = 14). The infection rate for patients with single dose prophylaxis was 2.05% (n = 9) and 1.53% (n = 5) for those that received the extended antibiotic regimen. No significant difference in infection rates between the different antibiotic regimens was found (p = 0.597). CONCLUSIONS: Overall rates of infection after TP prostate biopsy are very low. Our data indicate that single dose and extended regimen of antibiotic prophylaxis show similar infection rates. These findings support antibiotic stewardship and encourage further research into the appropriate regimen of prophylaxis for TP prostate biopsy.

Enhancing the Value of Surgical Entrustable Professional Activities through Integrative Learning Analytics.

OBJECTIVE: To demonstrate the value of integrating surgical resident Entrustable Professional Activity (EPA) data into a learning analytics platform that provides meaningful feedback for formative and summative decision-making. DESIGN: Description of the Surgical Entrustable Professional Activities (SEPA) analytics dashboard, and examples of summary analytics and intuitive display features. SETTING: Department of Surgery, University of Wisconsin Hospital and Clinics. PARTICIPANTS: Surgery residents, faculty, and residency program administrators. RESULTS: We outline the major functionalities of the SEPA dashboard and offer concrete examples of how these features are utilized by various stakeholders to support progressive entrustment decisions for surgical residents. CONCLUSIONS: Our intuitive analytics platform allows for seamless integration of SEPA microassessment data to support Clinical Competency Committee (CCC) decisions for resident evaluation and provides point of training feedback to faculty and trainees in support of progressive autonomy.

Mechanomyography as a Surgical Adjunct for Treatment of Chronic Entrapment Neuropathy: A Case Series.

BACKGROUND: Chronic entrapment neuropathy results in a clinical syndrome ranging from mild pain to debilitating atrophy. There remains a lack of objective metrics that quantify nerve dysfunction and guide surgical decision-making. Mechanomyography (MMG) reflects mechanical motor activity after stimulation of neuromuscular tissue and may indicate underlying nerve dysfunction. OBJECTIVE: To evaluate the role of MMG as a surgical adjunct in treating chronic entrapment neuropathies. METHODS: Patients 18 years or older with cubital tunnel syndrome (n = 8) and common peroneal neuropathy (n = 15) were enrolled. Surgical decompression of entrapped nerves was performed with intraoperative MMG of the hypothenar and tibialis anterior muscles. MMG stimulus thresholds (MMG-st) were correlated with compound muscle action potential (CMAP), motor nerve conduction velocity, baseline functional status, and clinical outcomes. RESULTS: After nerve decompression, MMG-st significantly reduced, the mean reduction of 0.5 mA (95% CI: 0.3-0.7, P < .001). On bivariate analysis, MMG-st exhibited significant negative correlation with common peroneal nerve CMAP ( P < .05), but no association with ulnar nerve CMAP and motor nerve conduction velocity. On preoperative electrodiagnosis, 60% of nerves had axonal loss and 40% had conduction block. The MMG-st was higher in the nerves with axonal loss as compared with the nerves with conduction block. MMG-st was negatively correlated with preoperative hand strength (grip/pinch) and foot-dorsiflexion/toe-extension strength ( P < .05). At the final visit, MMG-st significantly correlated with pain, PROMIS-10 physical function, and Oswestry Disability Index ( P < .05). CONCLUSION: MMG-st may serve as a surgical adjunct indicating axonal integrity in chronic entrapment neuropathies which may aid in clinical decision-making and prognostication of functional outcomes.