Imaging Biomarkers of Peripheral Nerves: Focus on Magnetic Resonance Neurography and Ultrasonography.

Peripheral neuropathy is a prevalent and debilitating condition affecting millions of individuals globally. Magnetic resonance neurography (MRN) and ultrasonography (US) are noninvasive methods offering comprehensive visualization of peripheral nerves, using anatomical and functional imaging biomarkers to ensure accurate evaluation. For optimized MRN, superior and high-resolution two-dimensional and three-dimensional imaging protocols are essential. The anatomical MRN and US imaging markers include quantitative measures of nerve and fascicular size and signal, and qualitative markers of course and morphology. Among them, quantitative markers of T2-signal intensity ratio are sensitive to nerve edema-like signal changes, and the T1-mapping technique reveals nerve and muscle tissue fatty and fibrous compositional alterations.The functional markers are derived from physiologic properties of nerves, such as diffusion characteristics or blood flow. They include apparent diffusion coefficient from diffusion-weighted imaging and fractional anisotropy and tractography from diffusion tensor imaging to delve into peripheral nerve microstructure and integrity. Peripheral nerve perfusion using dynamic contrast-enhanced magnetic resonance imaging estimates perfusion parameters, offering insights into nerve health and neuropathies involving edema, inflammation, demyelination, and microvascular alterations in conditions like type 2 diabetes, linking nerve conduction pathophysiology to vascular permeability alterations.Imaging biomarkers thus play a pivotal role in the diagnosis, prognosis, and monitoring of nerve pathologies, thereby ensuring comprehensive assessment and elevating patient care. These biomarkers provide valuable insights into nerve structure, function, and pathophysiology, contributing to the accurate diagnosis and management planning for peripheral neuropathy.

Utility of MR Neurography for the Evaluation of Peripheral Trigeminal Neuropathies in the Postoperative Period.

Peripheral trigeminal neuropathies are assessed by MR neurography for presurgical mapping. In this clinical report, we aimed to understand the utility of MR neurography following nerve-repair procedures. We hypothesized that postoperative MR neurography assists in determining nerve integrity, and worsening MR neurography findings will corroborate poor patient outcomes. Ten patients with peripheral trigeminal neuropathy were retrospectively identified after nerve-repair procedures, with postsurgical MR neurography performed from July 2015 to September 2023. Postsurgical MR neurography findings were graded as per postintervention category and subcategories of the Neuropathy Score Reporting and Data System (NS-RADS). Descriptive statistics of demographics, inciting injury, injury severity, NS-RADS scoring, and clinical outcomes were obtained. There were 6 women and 4 men (age range, 25-73 years). Most injuries resulted from third molar removals (8/10), with an average time from the inciting event to nerve-repair surgery of 6.1 (SD, 4.6) months. In Neuropathy Score Reporting and Data System-Injury (NS-RADS I), NS-RADS I-4 injuries (neuroma in continuity) were found in 8/10 patients, and NS-RADS I-5 injuries were found in the remaining patients, all confirmed at surgery. Surgeries performed included microdissection with neurolysis, neuroma excision, and nerve allograft with Axoguard protection. Three patients with expected postsurgical MR neurography findings experienced either partial improvement or complete symptom resolution, while among 7 patient with persistent or recurrent neuropathy on postsurgical MR neurography, one demonstrated partial improvement of sensation, pain, and taste and one experienced only pain improvement; the remaining 5 patients demonstrated no improvement. Postsurgical MR neurography consistently coincided with clinical outcomes related to pain, sensation, and lip biting and speech challenges. Lip biting and speech challenges were most amenable to recovery, even with evidence of persistent nerve pathology on postsurgical MR neurography.

Positive Effect of a Financial Incentive on Radiologist Compliance With Quality Metric Placement in Knee Radiography Reports.

PURPOSE: Ongoing quality improvement (QI) processes in the authors' department include the insertion of a Kellgren-Lawrence (KL) osteoarthritis grading template in knee radiography reports to decrease unnecessary MRI. However, uniform adoption of this grading system is lacking. Department-wide financial incentives were instituted to improve compliance with QI metrics. The purpose of this study was to evaluate the effect of a financial incentive on KL grading system use and to compare compliance rates of musculoskeletal (MSK) radiologists with those of general radiologists who were not financially incentivized to use KL grading. METHODS: Percentages of all knee radiography reports containing KL grading with standardized follow-up recommendations were determined by querying the departmental radiology database before and after the introduction of the new quality-based financial incentive. Preincentive compliance rates for MSK and general radiologists were compared with an adoption period and two separate 6-month postincentive periods. RESULTS: In total, 52,673 reports were retrospectively analyzed for KL grading use (41,670 reports interpreted by MSK radiologists and 11,003 interpreted by general radiologists). Increase in compliance was greatest among MSK radiologists' reports during the incentivized adoption period (from 36.1% to 53.2%). This improvement was sustained among MSK radiologists and averaged 62.7% during the most recently studied postimplementation period. A lesser degree of improvement in compliance was observed in nonincentivized general radiologists' reports (from 19.3% to 27.5%); during the postimplementation follow-up period, their compliance decreased to 26.5%. CONCLUSIONS: The introduction of a financial incentive resulted in significantly increased adoption of QI practices with sustained improvement among incentivized MSK radiologists compared with nonincentivized general radiologists.

Efficacy of MR Neurography of Peripheral Trigeminal Nerves: Correlation of Sunderland Grade versus Neurosensory Testing.

BACKGROUND AND PURPOSE: The current reference standard of diagnosis for peripheral trigeminal neuropathies (PTN) is clinical neurosensory testing (NST). MR neurography (MRN) is useful for PTN injury diagnosis, but it has only been studied in small case series. The aim of this study was to evaluate the agreement of Sunderland grades of nerve injury on MRN and NST by using surgical findings and final diagnoses as reference standards. MATERIALS AND METHODS: A total of 297 patient records with a chief complaint of PTN neuralgia were identified from the university database, and 70 patients with confirmed NST and MRN findings who underwent surgical nerve repair were included in the analysis. Cohen weighted kappa was used to calculate the strength of the agreement between the 3 modalities. RESULTS: There were 19 men and 51 women, with a mean age of 39.6 years and a standard deviation of 16.9 years. Most (51/70, 73%) injuries resulted from tooth extractions and implants. MRN injury grades agreed with surgical findings in 84.09% (37/44) of cases, and NST injury grades agreed with surgical findings in 74.19% (23/31) of cases. MRN and NST both showed similar agreement with surgery for grades I to III (70% and 71.43%). However, MRN showed a higher rate of agreement with surgery (88.24%) for injury grades IV and V than did NST (75%). CONCLUSIONS: MRN can objectively improve preoperative planning in patients with higher-grade nerve injuries.

Three-dimensional Volumetric Visceral and Subcutaneous Fat Analysis on Opportunistic Computed Tomography Imaging of Patients With Greater Trochanteric Pain Syndrome Compared With Those With Predominant Osteoarthritis: A Case-Control Study.

OBJECTIVE: This study aimed to address the gap in knowledge assessing the impact of visceral and subcutaneous body fat on 3-dimensional computed tomography imaging in patients with greater trochanteric pain syndrome (GTPS) in comparison with those primarily diagnosed with osteoarthritis (OA). MATERIALS AND METHODS: We evaluated adult patients with a confirmed diagnosis of GTPS from our institutional hip-preservation clinic spanning 2011 to 2022. Selection criteria included their initial clinic visit for hip pain and a concurrent pelvis computed tomography scan. These patients were age- and sex-matched to mild-moderate OA patients selected randomly from the database. Visceral and subcutaneous fat areas were measured volumetrically from the sacroiliac joint to the lesser trochanter using an independent software. Interreader reliability was also calculated. RESULTS: A total of 93 patients met the study criteria, of which 37 belonged to the GTPS group and 56 belonged to the OA group. Both groups were sex and race matched. Average age in GTPS and OA groups was 59.3 years and 56 years, respectively. For GTPS group, average body mass index was 28.9 kg/m2, and for the OA group, average body mass index was 29.9 kg/m2, with no significant difference (P > 0.05). Two-sample t test showed no significant differences in the visceral fat, subcutaneous fat, or the visceral fat to total fat volume ratio between the GTPS and OA groups. There was excellent interreader reliability. CONCLUSIONS: Our results indicate that there is no significant difference in fat distribution and volumes among GTPS and OA patients. This suggests that being overweight or obese may not be directly linked or contribute to the onset of GTPS. Other factors, such as gluteal tendinopathy, bursitis, or iliotibial band syndrome, might be responsible and need further investigation.

MRI-based Neuropathy Score Reporting And Data System (NS-RADS): multi-institutional wider-experience usability study of peripheral neuropathy conditions among 32 radiology readers.

OBJECTIVE: To determine the inter-reader reliability and diagnostic performance of classification and severity scales of Neuropathy Score Reporting And Data System (NS-RADS) among readers of differing experience levels after limited teaching of the scoring system. METHODS: This is a multi-institutional, cross-sectional, retrospective study of MRI cases of proven peripheral neuropathy (PN) conditions. Thirty-two radiology readers with varying experience levels were recruited from different institutions. Each reader attended and received a structured presentation that described the NS-RADS classification system containing examples and reviewed published articles on this subject. The readers were then asked to perform NS-RADS scoring with recording of category, subcategory, and most likely diagnosis. Inter-reader agreements were evaluated by Conger's kappa and diagnostic accuracy was calculated for each reader as percent correct diagnosis. A linear mixed model was used to estimate and compare accuracy between trainees and attendings. RESULTS: Across all readers, agreement was good for NS-RADS category and moderate for subcategory. Inter-reader agreement of trainees was comparable to attendings (0.65 vs 0.65). Reader accuracy for attendings was 75% (95% CI 73%, 77%), slightly higher than for trainees (71% (69%, 72%), p = 0.0006) for nerves and comparable for muscles (attendings, 87.5% (95% CI 86.1-88.8%) and trainees, 86.6% (95% CI 85.2-87.9%), p = 0.4). NS-RADS accuracy was also higher than average accuracy for the most plausible diagnosis for attending radiologists at 67% (95% CI 63%, 71%) and for trainees at 65% (95% CI 60%, 69%) (p = 0.036). CONCLUSION: Non-expert radiologists interpreted PN conditions with good accuracy and moderate-to-good inter-reader reliability using the NS-RADS scoring system. CLINICAL RELEVANCE STATEMENT: The Neuropathy Score Reporting And Data System (NS-RADS) is an accurate and reliable MRI-based image scoring system for practical use for the diagnosis and grading of severity of peripheral neuromuscular disorders by both experienced and general radiologists. KEY POINTS: • The Neuropathy Score Reporting And Data System (NS-RADS) can be used effectively by non-expert radiologists to categorize peripheral neuropathy. • Across 32 different experience-level readers, the agreement was good for NS-RADS category and moderate for NS-RADS subcategory. • NS-RADS accuracy was higher than the average accuracy for the most plausible diagnosis for both attending radiologists and trainees (at 75%, 71% and 65%, 65%, respectively).

Automatic Protocolling of Non-contrast Musculoskeletal MRIs Does Not Result in Increase in Patient Recall Rates for Contrast-Enhanced Studies.

RATIONALE AND OBJECTIVES: Physicians spend large amounts of time on protocolling imaging studies, limiting their time spent on other essential clinical tasks. Most musculoskeletal (MSK) MRI studies are performed for the evaluation of joint pain and internal derangements and usually require no intravenous contrast. Contrast-enhanced MRI studies are performed for the evaluation of infection, suspected or established tumor, and rheumatological conditions. Protocolling all MSK MRI studies takes time away from other important tasks during the workday. Routine joint MRI scans have established set of sequences, and thus, could be scheduled and performed without special protocols by the radiologists. In a large tertiary care center like ours with multiple MRI magnets, we set up a process of automated protocoling and scheduling of non-contrast joint MRI scans ordered by referring doctors. This project's purpose was to assess the effect of this newly established process of 'automatic protocoling and scheduling' of MSK MRI scans on the rate of overlooked MRI exams that may have required contrast examinations, and on the patient recall-rate to obtain follow-up post-contrast sequences for further diagnostic characterization. METHODS: All MSK reports of MRIs during the last two months of the years before and after the implementation of automatic protocolling (intervention) were searched for the presence of indications related to neoplasms, infections, and rheumatological conditions. For each of the three disease categories, we determined the number of MRIs obtained with and without contrast before and after the intervention. For each matching study obtained without contrast, the patient chart was reviewed for contraindications to contrast, positive final diagnosis, whether interpreting radiologist mentioned the exam being limited by lack of contrast, and recommendations for a follow-up contrast enhanced study. RESULTS: A total of 846 MSK MRIs were performed prior to intervention and 822 MRIs were performed afterwards. Overall, 25% of the studies were performed without contrast prior to the intervention, and 31% of studies were performed without contrast afterwards (Chi square 0.07, p-value 0.79). No report contained a recommendation for contrast enhanced follow-up study before or after the intervention. CONCLUSION: Automatic protocolling of routine MSK non-contrast MRI studies resulted in statistically insignificant, minimal increase in the overall number of non-contrast enhanced studies obtained for work up of neoplasms, infections, and rheumatological conditions. There was no increase in patient recall rate for additional post contrast sequences and the new process resulted in time savings to fellows and other physicians, being not distracted from other important tasks.

The Relationship Between Postoperative Patient-Reported Psychological Outcomes and Preoperative Pain Characteristics in Patients Who Underwent Periacetabular Osteotomy.

This study sought to investigate the relationship between multiple preoperative characteristics of pain (maximum pain severity location, the presence of pain in certain locations, the highest level of pain, and the number of pain locations) and psychological outcome measures as reported by patients. Fifty-four hips (50 patients) that underwent periacetabular osteotomy to treat acetabular dysplasia between February 2017 and July 2020 were reviewed using the Depression, Anxiety, and Stress Scale-21 (DASS21), Hospital Anxiety and Depression Scale (HADS), and Pain Catastrophizing Scale (PCS), radiographic analysis, and questionnaires concerning pain severity/location. Twenty-six hips had their worst pain in the groin, whereas 28 hips had greater or equal levels of pain at another location. There was no significant difference between these two locations on any of the postoperative psychological outcomes (HADS, P=.53; DASS21, P=.85; PCS, P=.97). Additionally, there was not a significant relationship between pain in any location other than the groin and any postoperative psychological outcomes (P≥.08). Finally, the highest level of preoperative pain and the number of locations of pain demonstrated no significant relationship with postoperative psychological outcomes (maximum severity: HADS, P=.28; DASS21, P=.49; PCS, P=.57; number of pain locations: HADS, P=.47; DASS21, P=.60; PCS, P=.35). Variance in preoperative pain location, severity, and number of pain locations seemingly does not result in any significant effect on postoperative psychological outcomes. Thus, a large range of patients with acetabular dysplasia may experience similar, favorable psychological outcomes from treatment with periacetabular osteotomy notwithstanding the characteristics of preoperative pain. [Orthopedics. 2024;47(1):28-33.].

Association of plexiform and diffuse neurofibromas with malignant peripheral nerve sheath tumor in NF I patients: a whole-body MRI assessment.

OBJECTIVE: The aim of this study is to evaluate neurofibromatosis type 1 (NF1) patients with whole-body MRI (WBMRI) to investigate the frequency of plexiform neurofibromas (pNFs), diffuse neurofibromas (dNFs), and malignant peripheral nerve sheath tumors (MPNSTs). MATERIALS AND METHODS: In this retrospective cross-sectional study, between the years 2015 and 2023, 83 consecutive patients with known NF1 underwent a total of 110 WBMRI screenings for MPNST using a standardized institutional protocol. The lesions are categorized as discrete lesions, pNFs, dNFs, and MPNSTs. Histopathology served as the reference standard for all MPNSTs. RESULTS: Among the 83 patients analyzed, 53 (64%) were women and 30 were men (36%) of ages 36.94±14.43 years (range, 15-66 years). Of the 83 patients, 33 have a positive family history of NF1 and positive genetic studies. Seven of 83 (8%) have only dNF, 20/83 (24%) have pNF, 28/83 (34%) have both dNF and pNF, and 28/83 (34%) have neither. Of the 83 patients, eight (9.6%) were diagnosed with nine total MPNSTs. Age range for patients with MPNSTs at time of diagnosis was 22-51, with an average age of 33.4 years. Only one MPNST (11%) developed from underlying pNF 4 years after WBMRI along the right bronchial tree. Three of eight (37.5%) patients with MPNST died within 5 years of pathologic diagnosis. CONCLUSION: This study suggests the absence of a predisposition for development of MPNST from pNFs and dNFs in the setting of NF1. As such, these lesions may not need special surveillance compared to discrete peripheral nerve sheath tumors.

Correlation Between Traditional Anteroposterior Radiographic Measurements With Lateral Radiographic Measurements Following Triplanar Correction of Hallux Valgus and With Patient-Reported Outcomes From a Prospective Multicenter Trial.

Hallux valgus (HV) is a common condition in which the first ray is deformed, leading to pain and altered joint mechanics. A variety of radiographic measurements are used to evaluate HV. Little is known about measurements used in the assessment of HV on lateral radiographs compared to anteroposterior (AP) radiographs. The primary aim of this study was to correlate lateral measurements with AP measurements pre and postoperatively. The secondary aim was to correlate lateral measurements with patient-reported outcome measures (PROMs) pre and postoperatively. One hundred eighty-three patients were initially enrolled in the study. Two fellowship-trained musculoskeletal radiologists independently performed all measurements. On AP radiographs, hallux valgus angle (HVA) and intermetatarsal angle (IMA) were measured. On lateral radiographs, sagittal IMA, Meary's angle, and sagittal first ray length were measured. Measurements were recorded at baseline and 6, 12, and 24 months postoperatively. Intraclass correlation coefficients (ICCs) were used for inter-reader analysis. ICCs were moderate to very strong among readers. There were significant but weak correlations between lateral measurements and AP measurements. For at least 1 timepoint, IMA correlated with sagittal IMA, sagittal first ray length, and Meary's angle. HVA only correlated with sagittal first ray length. These correlations were all weak in magnitude. There were a few significant but weak correlations between the measurements in the study and PROMs. This study showed that sagittal IMA, sagittal first ray length, and Meary's angle are not predictive of AP measurements or patient outcomes and are not useful in preoperative assessment of HV.

Frequency of Coexistent Spinal Segment Variants: Retrospective Analysis in Asymptomatic Young Adults.

BACKGROUND AND PURPOSE: Spinal segment variants are highly prevalent and can potentially lead to incorrect spinal enumeration and, consequently, interventions or surgeries at the wrong vertebral levels. Our aim was to assess the prevalence of spinal segment variants and to study the potential association among these variants in a population without histories of spine symptoms. MATERIALS AND METHODS: Consecutive computed tomography exams of 450 young adults originally evaluated for non-spinal conditions and without a history of spinal diseases from a single institution. In addition to using descriptive statistics for reporting frequencies of spinal segment variants, the association between these variants was studied by calculating odds ratios and their 95% confidence interval. Consecutive CT exams were evaluated to determine the total number of presacral segments, presence of cervical rib, thoracolumbar transitional vertebra, iliolumbar ligament, and lumbosacral transitional vertebra. RESULTS: The spinal segment distribution variants (an atypical number of presacral segments or an atypical distribution of thoracolumbar vertebrae), cervical rib, thoracolumbar transitional vertebra, and lumbosacral transitional vertebra were reported in 23.8%, 4.2%, 15.3%, and 26.4% of cases in our study population. The presence of a cervical rib or a thoracolumbar transitional vertebra was associated with concurrent lumbosacral transitional vertebra (OR = 3.28; 95% CI, 1.29-8.47 and 1.87; 95% CI, 1.08-3.20, respectively). The inability to visualize the iliolumbar ligament was also associated with the presence of cervical ribs (OR = 3.06; 95% CI, 1.18-7.80). CONCLUSIONS: In a population of asymptomatic young adults, spinal segment variants are both highly prevalent with a high rate of coexistence. When a spinal segment variant (eg, transitional vertebra) is diagnosed, additional imaging might be considered for accurate spine enumeration before interventions or operations.

Three-dimensional magnetic resonance neurography aids in detection of brachial plexus nerve root signal and size alterations in patients with amyotrophic lateral sclerosis: a case-control study.

Background: Since previous histopathological studies have shown a distal to proximal gradient of axonal damage in peripheral nerves of patients with amyotrophic lateral sclerosis (ALS), it would be worthwhile to evaluate consequence of such changes on magnetic resonance imaging (MRI). The aim of this study was to assess proximal-distal longitudinal signal and size alterations of brachial plexus nerve roots in ALS patients using 3-dimensional (3D) magnetic resonance neurography (MRN). Methods: A total of 21 ALS patients and 19 controls were evaluated. The diameters and signal-to-noise (SNR) ratio values of C5-C8 roots were measured at five points from proximal to distal sites. Student's t-test was performed to compare the differences at each point between two groups. Linear regression was performed for each nerve root, and the differences in linear regression slopes between two groups were analyzed. Receiver operating characteristic (ROC) analysis was performed for the diameter and SNR value ratio of the distal to the proximal points. Results: Interobserver agreement was excellent [intraclass correlation coefficient (ICC): 0.802-0.913]. The diameters and SNR values of C5-C8 roots showed a significant decrease (P<0.05) from proximal to distal except SNR value of C5 root in controls. The slope values of diameters in ALS were -0.01924 for C5, -0.04404 for C6, -0.06228 for C7, and -0.06464 for C8. The slope values of SNR values in ALS were -10.14 for C5, -12.86 for C6, -15.99 for C7, and -19.06 for C8. The slope of nerve diameters and SNR values for ALS patients were more negatively sloped than controls (P<0.05) except SNR values of C5 and C7 roots. The ROC analysis confirmed that the diameter and SNR value ratio could differentiate ALS patients from controls with high accuracy. The cutoff values of diameter ratio were 0.7418 for C5, 0.6952 for C6, 0.6431 for C7, and 0.7147 for C8. The cutoff values of SNR value ratio were 0.5989 for C5, 0.6516 for C6, 0.6065 for C7, and 0.6758 for C8. Conclusions: Proximal-distal longitudinal diameters and SNR values decreased significantly for brachial plexus nerve roots in ALS patients with larger differences in slopes compared to controls. These results reflect pathophysiological changes of ALS and may be helpful in improving the diagnosis of ALS.

3D isotropic MRI of ankle: review of literature with comparison to 2D MRI.

The ankle joint has complex anatomy with different tissue structures and is commonly involved in traumatic injuries. Magnetic resonance imaging (MRI) is the primary imaging modality used to assess the soft tissue structures around the ankle joint including the ligaments, tendons, and articular cartilage. Two-dimensional (2D) fast spin echo/turbo spin echo (FSE/TSE) sequences are routinely used for ankle joint imaging. While the 2D sequences provide a good signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with high spatial resolution, there are some limitations to their use owing to the thick slices, interslice gaps leading to partial volume effects, limited fluid contrast, and the need to acquire separate images in different orthogonal planes. The 3D MR imaging can overcome these limitations and recent advances have led to technical improvements that enable its widespread clinical use in acceptable time periods. The volume imaging renders the advantage of reconstructing into thin continuous slices with isotropic voxels enabling multiplanar reconstructions that helps in visualizing complex anatomy of the structure of interest throughout their course with improved sharpness, definition of anatomic variants, and fluid conspicuity of lesions and injuries. Recent advances have also reduced the acquisition time of the 3D datasets making it more efficient than 2D sequences. This article reviews the recent technical developments in the domain 3D MRI, compares imaging with 3D versus 2D sequences, and demonstrates the use-case scenarios with interesting cases, and benefits of 3D MRI in evaluating various ankle joint components and their lesions.

Single-Plane 3-Dimensional Isotropic Spin-Echo Magnetic Resonance Imaging Reconstructions of Shoulder Exhibit Superior Correlation to Surgical Findings Than 2-Dimensional Dixon Multiplanar Magnetic Resonance Imaging.

OBJECTIVE: The aim of the study is to evaluate concordance of multiplanar 2-dimensional magnetic resonance imaging (2D-MRI) versus 3D isotropic MRI for rotator cuff and labral tears with the reference standard of arthroscopic surgical findings. METHODS: It was an institutional review board-approved retrospective single-center study of consecutive preoperative patients with isotropic 3D-MRI on 3-Tesla scanners, multiplanar 2D-MRI, and shoulder arthroscopy. Scapular plane-oriented contiguous multiplanar reconstructions of 3D-images were evaluated by 2 experienced fellowship-trained musculoskeletal radiologists. Variables included the following: labral tear presence and rotator-cuff tear Ellman grade, thickness, and width. Sensitivities (Sen) and specificities (Spe) were calculated for binary variables. Mean squared errors (MSE) were calculated for ordinal variables. Lower MSE indicated higher concordance. RESULTS: Seventy-two patients (43 female) with a mean age of 50.75 ± 9.76 years were evaluated. For infraspinatus-tear presence, 3D-MRI showed higher sensitivity (0.96) and specificity (0.68) than 2D-MRI (Sen = 0.85, Spe = 0.32) (Psen = 0.005, Pspe = 0.002). For subscapularis-tear presence, 3D-MRI showed higher sensitivity (0.94) and specificity (0.73) compared with 2D-MRI (Sen = 0.83, Spe = 0.56) (Psen = 0.02, Pspe = 0.04). For supraspinatus-tear presence, there was no significant difference between 3D-MRI (Sen =0.96, Spe = 0.67) compared with 2D-MRI (Sen = 0.98, Spe = 0.83) (Psen = 0.43, Pspe = 0.63). For infraspinatus-tear thickness, 3D-MRI showed lower MSE (0.35) compared with 2D-MRI MSE (0.82) (P = 0.01). For subscapularis-tear thickness, 3D-MRI had lower MSE (0.31) compared with 2D-MRI MSE (0.51) (P = 0.007). However, no difference noted for supraspinatus-tear thickness when comparing 3D-MRI MSE (0.39) and 2D-MRI MSE (0.51) (P = 0.49). For labral-tear presence, 3D-MRI had a lower MSE (0.20) compared with 2D-MRI MSE (0.57) (P < 0.001). CONCLUSIONS: Three-dimensional MRI of the shoulder is time efficient with a shorter acquisition time and exhibits comparable with superior correlation to surgical findings than 2D-MRI for detection of labral tears and some rotator cuff tears. Three-dimensional MRI may be used in place of traditional 2D-MRI in detection of soft-tissue shoulder injury in centers equipped to do so.

Deep learning generated lower extremity radiographic measurements are adequate for quick assessment of knee angular alignment and leg length determination.

PURPOSE: Angular and longitudinal deformities of leg alignment create excessive stresses across joints, leading to pain and impaired function. Multiple measurements are used to assess these deformities on anteroposterior (AP) full-length radiographs. An artificial intelligence (AI) software automatically locates anatomical landmarks on AP full-length radiographs and performs 13 measurements to assess knee angular alignment and leg length. The primary aim of this study was to evaluate the agreements in LLD and knee alignment measurements between an AI software and two board-certified radiologists in patients without metal implants. The secondary aim was to assess time savings achieved by AI. METHODS: The measurements assessed in the study were hip-knee-angle (HKA), anatomical-tibiofemoral angle (aTFA), anatomical-mechanical-axis angle (AMA), joint-line-convergence angle (JLCA), mechanical-lateral-proximal-femur-angle (mLPFA), mechanical-lateral-distal-femur-angle (mLDFA), mechanical-medial-proximal-tibia-angle (mMPTA), mechanical-lateral-distal-tibia- angle (mLDTA), femur length, tibia length, full leg length, leg length discrepancy (LLD), and mechanical axis deviation (MAD). These measurements were performed by two radiologists and the AI software on 164 legs. Intraclass-correlation-coefficients (ICC) and Bland-Altman analyses were used to assess the AI's performance. RESULTS: The AI software set incorrect landmarks for 11/164 legs. Excluding these cases, ICCs between the software and radiologists were excellent for 12/13 variables (11/13 with outliers included), and the AI software met performance targets for 11/13 variables (9/13 with outliers included). The mean reading time for the AI algorithm and two readers, respectively, was 38.3, 435.0, and 625.0 s. CONCLUSION: This study demonstrated that, with few exceptions, this AI-based software reliably generated measurements for most variables in the study and provided substantial time savings.

Diagnostic efficacy of posterior tibialis tendon dysfunction: a systematic review of literature.

OBJECTIVE: To perform a systematic review to examine the diagnostic accuracy of magnetic resonance imaging, ultrasonography, and radiography in the evaluation of posterior tibial tendon dysfunction (PTTD). MATERIALS AND METHODS: Medline, Scopus, Embase, and The Cochrane Central Register of Controlled Trials (CENTRAL) were searched for relevant studies through April 2023. The study quality was assessed using the QUADAS-2 scoring system. RESULTS: Of the initial 634 studies, 12 studies met the quality criteria and were included, with 645 PTTs evaluated with MRI, 133 with US, and 97 with radiography. MRI was found to be more sensitive and specific than ultrasound, radiography, and clinical evaluation for detecting PTTD, with a sensitivity of up to 95%, specificity of up to 100%, and accuracy of 96% for detecting PTT tears. US showed a sensitivity of 80% and specificity of 90% for diagnosing tendinopathy, and a sensitivity of 90% and specificity of 80% for diagnosing peritendinosis when compared to MRI. Weight-bearing radiographs had a sensitivity of 71.4%, specificity of 88.9%, and diagnostic accuracy of 81.3% when diagnosing PTT ruptures. Various radiologic measurements were also found to have a significant relationship with PTT tears but were poorly correlated with PTT tendinosis and isolated tenosynovitis. CONCLUSION: Magnetic resonance imaging is the preferred imaging tool for evaluating patients with posterior tibial tendon dysfunction, with higher diagnostic accuracy, sensitivity, and specificity compared to ultrasound and radiographic imaging. However, initial imaging with ultrasound and radiographs may be used due to their availability and cost-effectiveness. CLINICAL RELEVANCE: PTTD affects 3% of women ≥ 40 years and 10% of adults ≥ 65 years globally. Using the appropriate imaging study, MRI ensures that patients suffering from PTTD are diagnosed and treated in a timely manner. KEY POINTS: • This review aimed to determine the diagnostic accuracy of MRI, ultrasonography, and radiography in evaluating PTTD. • MRI outperformed ultrasound and radiography, with higher sensitivity, specificity, and accuracy in detecting PTT tears. • MRI is the preferred imaging modality for the initial diagnosis of PTTD.

Comparison between ZOOMit DWI and conventional DWI in the assessment of foot and ankle infection: a prospective study.

OBJECTIVE: The study aimed to compare ZOOMit diffusion-weighted imaging (DWI) MRI with conventional DWI MRI for visualizing small bones in the foot, soft tissue abscesses, and osteomyelitis. MATERIALS AND METHODS: The cohort consisted of a consecutive series of patients with potential foot and ankle infections referred for MR imaging. Patients were imaged using both conventional and ZOOMit DWI in the same setting. Blinded reads were then conducted in separate settings and independent of known clinical diagnosis by two expert radiologists. The results from the reads were compared statistically using paired t-tests and with biopsy specimen analysis, both anatomopathological and microbiological. RESULTS: There was improvement in fat suppression using ZOOMit sequence compared to conventional DWI (p = .001) with no significant difference in motion artifacts (p = .278). ZOOMit had a higher rate of concordance with pathology findings for osteomyelitis (72%, 31/43 cases) compared with conventional DWI (60%, 26/43 cases). ZOOMit also identified 46 additional small bones of the foot and ankle (405/596, 68.0%) than conventional DWI (359/596, 60.2%). Conventional DWI however exhibited a more negative contrast-to-noise ratio (CNR) than ZOOMit (p = 0.001). CONCLUSION: ZOOMit DWI improves distal extremity proton diffusion assessment and helps visualize more bones in the foot, with less image distortion and improved fat saturation at the expense of reduced CNR. This makes it a viable option for assessing lower extremity infections. CLINICAL RELEVANCE STATEMENT: This study highlights the novel utilization of ZOOMit diffusion-weighted imaging (DWI) for the assessment of lower extremity lesions compared to conventional DWI. KEY POINTS: • Distal extremity diffusion-weighted imaging (DWI) is often limited. • ZOOMit DWI displayed improved fat suppression with less motion artifacts and better visualization of the lower extremity bones than conventional DWI. • ZOOMit shows decreased contrast-to-noise ratio than conventional DWI.

Predictive Value of Radiographic and Magnetic Resonance Imaging Characteristics on Patient Outcomes in Confirmed Acute Osteomyelitis of the Extremities.

OBJECTIVE: The aim of this study was to determine whether imaging characteristics on plain radiography, magnetic resonance imaging (MRI), and diffusion-weighted imaging are predictive of patient outcomes in cases of confirmed osteomyelitis (OM). MATERIALS AND METHODS: In this cross-sectional study, 3 experienced musculoskeletal radiologists evaluated pathologically proven cases of acute extremity OM and recorded imaging characteristics on plain radiographs, MRI, and diffusion-weighted imaging. These characteristics were then compared with the patient outcomes after a 3-year follow-up using length of stay, amputation-free survival, readmission-free survival, and overall survival using multivariate Cox regression analysis. Hazard ratio and corresponding 95% confidence intervals are reported. False discovery rate-adjusted P values were reported. RESULTS: For the 75 consecutive cases of OM in this study, multivariate Cox regression analysis adjusting for sex, race, age, body mass index, erythrocyte sedimentation rate, C-reactive protein, and white blood cell count showed no correlation among any of the recorded characteristics on imaging and patient outcomes. Despite the high sensitivity and specificity of MRI for diagnosing OM, there was no correlation between MRI characteristics and patient outcomes. Furthermore, patients with coexistent abscess of the soft tissue or bone with OM had comparable outcomes using the previously mentioned metrics of length of stay, amputation-free survival, readmission-free survival, and overall survival. CONCLUSION: Neither radiography nor MRI features predict patient outcomes in extremity OM.

Two-Dimensional and 3-Dimensional MRI Assessment of Progressive Collapsing Foot Deformity-Adult Acquired Flat Foot Deformity.

This article is meant to serve as a reference for radiologists, orthopedic surgeons, and other physicians to enhance their understanding of progressive collapsing foot deformity, also known as adult acquired flat foot deformity. Pathophysiology, imaging findings, especially on MRI and 3-dimensional MRI are discussed with relevant illustrations so that the readers can apply these principles in their practice for better patient managements.

Relationships between self-perceived and clinical expression of pain and function differ based on the underlying pathology of the human hip.

BACKGROUND: Patient-reported outcomes are commonly used to assess patient symptoms. The effect of specific hip pathology on relationships between perceived and objectively measured symptoms remains unclear. The purpose of this study was to evaluate differences of function and pain in patients with FAIS and DDH, to assess the correlation between perceived and objective function, and to determine the influence of pain on measures of function. METHODS: This prospective cross-sectional study included 35 pre-operative patients (60% female) with femoroacetabular impingement syndrome (FAIS) and 37 pre-operative patients (92% female) with developmental dysplasia of the hip (DDH). Objectively measured function (6-min walk [6MWT], single leg hop [SLHT], Biodex sway [BST], hip abduction strength [HABST], and STAR excursion balance reach [STAR] tests), patient-reported function (UCLA Activity, Hip Outcome Score [HOS], Short Form 12 [SF-12], and Hip Disability and Osteoarthritis Outcome Score [HOOS]), and patient-reported pain (HOOS Pain, visual analogue scale (VAS), and a pain location scale) were collected during a pre-surgical clinic visit. Between-group comparisons of patient scores were performed using Wilcoxon Rank-Sum tests. Within-group correlations were analyzed using Spearman's rank correlation coefficients. Statistical correlation strength was defined as low (r = ± 0.1-0.3), moderate (r = ± 0.3-0.5) and strong (r > ± 0.5). RESULTS: Patients with DDH reported greater pain and lower function compared to patients with FAIS. 6MWT distance was moderately-to-strongly correlated with a number of patient-reported measures of function (FAIS: r = 0.37 to 0.62, DDH: r = 0.36 to 0.55). Additionally, in patients with DDH, SLHT distance was well correlated with patient reported function (r = 0.37 to 0.60). Correlations between patient-reported pain and objectively measured function were sparse in both patient groups. In patients with FAIS, only 6MWT distance and HOOS Pain (r = -0.53) were significantly correlated. In patients with DDH, 6MWT distance was significantly correlated with VAS Average (r = -0.52) and Best (r = -0.53) pain. CONCLUSION: Pain is greater and function is lower in patients with DDH compared to patients with FAIS. Moreover, the relationship between pain and function differs between patient groups. Understanding these differences is valuable for informing treatment decisions. We recommend these insights be incorporated within the clinical continuum of care, particularly during evaluation and selection of surgical and therapeutic interventions.