Pseudolesions involving bone and soft tissue regarding orthopedic oncology.

Pseudolesions in bone and muscle are encountered mostly incidentally in routine imaging studies, especially due to the recent advancements on many different imaging modalities. These lesions can be categorized into the following categories: normal variants; congenital; iatrogenic; degenerative; and postoperative. In this review, we discuss the many different radiological characteristics of musculoskeletal pseudolesions that appear on imaging, which can prevent non-essential additional studies.

Musculoskeletal Pitfalls on Molecular Imaging Studies of Oncologic Patients: How to Stay Out of Trouble.

An increasing amount of molecular imaging studies are ordered each year for an oncologic population that continues to expand and increase in age. The importance of these studies in dictating further care for oncologic patients underscores the necessity of differentiating benign from malignant findings, particularly for a population in whom incidental findings are common. The aim of this review is to provide pictorial examples of benign musculoskeletal pathologies which may be found on molecular imaging and which may be mistaken for malignant processes. Imaging examples are provided in the form of radiographs, bone scintigraphy, computed tomography, and fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scans. Special attention is paid to specific features that help narrow the differential diagnosis and distinguish benign from malignant processes, with the goal of avoiding unnecessary invasive procedures.

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).

Whole-Body MRI in Limb Girdle Muscular Dystrophy Type R1/2A: Correlation With Clinical Scores.

INTRODUCTION/AIM: The most common limb girdle muscular dystrophy (LGMD) worldwide is LGMD type R1 (LGMDR1). The aim of this study was to correlate the MRI findings with functional scores and to describe the whole-body MRI (WBMRI) pattern in a LGMDR1 Brazilian cohort. METHODS: LGMDR1 patients under follow-up in three centers were referred for the study. Clinical data were collected and a functional evaluation was performed, consisting of Gardner-Medwin and Walton (GMW) and Brooke scales. All patients underwent a WBMRI study (1.5T) with axial T1 and STIR images. Fifty-one muscles were semiquantitatively assessed regarding fatty infiltration and muscle edema. RESULTS: The study group consisted of 18 patients. The highest fatty infiltration scores involved the serratus anterior, biceps femoris long head, adductor magnus, and lumbar erector spinae. There was a latero-medial and caudo-cranial descending gradient of involvement of the paravertebral muscles, with erector spinae being significantly more affected than the transversospinalis muscles (p < 0.05). A striped appearance that has been dubbed the "pseudocollagen sign" was present in 72% of the patients. There was a positive correlation between the MRI score and GMW (Rho:0.83) and Brooke (Rho:0.53) scores. DISCUSSION: WBMRI in LGMDR1 allows a global patient evaluation including involvement of the paraspinal muscles, usually an underestimated feature in the clinical and imaging study of myopathies. Knowledge of the WBMRI pattern of LGMDR1 involvement can be useful in the diagnostic approach and in future studies to identify the best target muscles to serve as outcome measures in clinical trials.

Imaging of Paget's Disease of Bone.

Paget's disease is a metabolic bone disorder affecting the elderly and characterized by bone resorption followed by compensatory bone formation. Radiography is the imaging modality of choice for the diagnosis whereas bone scintigraphy helps stage the extent of the disease and assess response to treatment. MRI and CT are important imaging methods in the assessment of complications and surgical planning. Osteolytic lesions of Paget's first phase present with well-defined margins on radiographs, most commonly in the femur, pelvis, and skull. Cortical thickening, trabecular coarsening, bone marrow sclerosis, and deformities of long bones are present in the mixed- and late-sclerotic phases.

Soft Tissue Tumors: Imaging Features of Primary Soft Tissue Malignancies.

Imaging in soft tissue sarcomas (STS) plays a key role in diagnosis, surgical planning, and assessment of treatment response, and surveillance. In this review, we discuss the imaging features-with an emphasis on MR imaging-of nonvisceral STS, highlighting representative tumors from the various WHO subtypes. We focus on imaging findings that may aid the radiologist in categorizing tumor subtype and grade, and that affect disease staging.

Perceptual and Neuromuscular Responses Adapt Similarly Between High-Load Resistance Training and Low-Load Resistance Training With Blood Flow Restriction.

ABSTRACT: Teixeira, EL, Painelli, VdS, Schoenfeld, BJ, Silva-Batista, C, Longo, AR, Aihara, AY, Cardoso, FN, Peres, BdA, and Tricoli, V. Perceptual and neuromuscular responses adapt similarly between high-load resistance training and low-load resistance training with blood flow restriction. J Strength Cond Res 36(9): 2410-2416, 2022-This study compared the effects of 8 weeks of low-load resistance training with blood flow restriction (LL-BFR) and high-load resistance training (HL-RT) on perceptual responses (rating of perceived exertion [RPE] and pain), quadriceps cross-sectional area (QCSA), and muscle strength (1 repetition maximum [RM]). Sixteen physically active men trained twice per week, for 8 weeks. One leg performed LL-BFR (3 sets of 15 repetitions, 20% 1RM), whereas the contralateral leg performed HL-RT (3 sets of 8 repetitions, 70% 1RM). Rating of perceived exertion and pain were evaluated immediately after the first and last training sessions, whereas QCSA and 1RM were assessed at baseline and after training. Rating of perceived exertion was significantly lower (6.8 ± 1.1 vs. 8.1 ± 0.8, p = 0.001) and pain significantly higher (7.1 ± 1.2 vs. 5.8 ± 1.8, p = 0.02) for LL-BFR than that for HL-RT before training. Significant reductions in RPE and pain were shown for both protocols after training (both p < 0.0001), although no between-protocol differences were shown in absolute changes ( p = 0.10 and p = 0.48, respectively). Both LL-BFR and HL-RT were similarly effective in increasing QCSA (7.0 ± 3.8% and 6.3 ± 4.1%, respectively; both p < 0.0001) and 1RM (6.9 ± 4.1% and 13.7 ± 5.9%, respectively; both P < 0.0001), although absolute changes for 1RM in HL-RT were greater than LL-BFR ( p = 0.001). In conclusion, LL-BFR produces lower RPE values and a higher pain perception than HL-RT. However, consistent application of these approaches result in chronic adaptations so that there are no differences in perceptual responses over the course of time. In addition, muscle strength is optimized with HL-RT despite similar increases in muscle hypertrophy between conditions.

MR imaging of inherited myopathies: a review and proposal of imaging algorithms.

PURPOSE OF REVIEW: The aims of this review are to discuss the imaging modalities used to assess muscle changes in myopathies, to provide an overview of the inherited myopathies focusing on their patterns of muscle involvement in magnetic resonance imaging (MR), and to propose up-to-date imaging-based diagnostic algorithms that can help in the diagnostic workup. CONCLUSION: Familiarization with the most common and specific patterns of muscular involvement in inherited myopathies is very important for radiologists and neurologists, as imaging plays a significant role in diagnosis and follow-up of these patients. KEY POINTS: • Imaging is an increasingly important tool for diagnosis and follow-up in the setting of inherited myopathies. • Knowledge of the most common imaging patterns of muscle involvement in inherited myopathies is valuable for both radiologists and neurologists. • In this review, we present imaging-based algorithms that can help in the diagnostic workup of myopathies.

Blood Flow Restriction Does Not Promote Additional Effects on Muscle Adaptations When Combined With High-Load Resistance Training Regardless of Blood Flow Restriction Protocol.

ABSTRACT: Teixeira, EL, Ugrinowitsch, C, de Salles Painelli, V, Silva-Batista, C, Aihara, AY, Cardoso, FN, Roschel, H, and Tricoli, V. Blood flow restriction does not promote additional effects on muscle adaptations when combined with high-load resistance training regardless of blood flow restriction protocol. J Strength Cond Res 35(5): 1194-1200, 2021-The aim of this study was to investigate, during high-load resistance training (HL-RT), the effect of blood flow restriction (BFR) applied during rest intervals (BFR-I) and muscle contractions (BFR-C) compared with HL-RT alone (no BFR), on maximum voluntary isometric contraction (MVIC), maximum dynamic strength (one repetition maximum [1RM]), quadriceps cross-sectional area (QCSA), blood lactate concentration ([La]), and root mean square of the surface electromyography (RMS-EMG) responses. Forty-nine healthy and untrained men (25 ± 6.2 years, 178.1 ± 5.3 cm and 78.8 ± 11.6 kg) trained twice per week, for 8 weeks. One leg of each subject performed HL-RT without BFR (HL-RT), whereas the contralateral leg was randomly allocated to 1 of 2 unilateral knee extension protocols: BFR-I or BFR-C (for all protocols, 3 × 8 repetitions, 70% 1RM). Maximum voluntary isometric contraction, 1RM, QCSA, and acute changes in [La] and RMS-EMG were assessed before and after training. The measurement of [La] and RMS-EMG was performed during the control sessions with the same relative load obtained after the 1RM test, before and after training. Similar increases in MVIC, 1RM, and QCSA were demonstrated among all conditions, with no significant difference between them. [La] increased for all protocols in pre-training and post-training, but it was higher for BFR-I compared with the remaining protocols. Increases in RMS-EMG occurred for all protocols in pre-training and post-training, with no significant difference between them. In conclusion, despite of a greater metabolic stress, BFR inclusion to HL-RT during rest intervals or muscle contraction did not promote any additive effect on muscle strength and hypertrophy.

Differential Diagnosis of Facet Joint Disorders.

Spinal pain due to facet joint disease is difficult to diagnose since the clinical history and physical examination findings are usually nonspecific. Facet joint disorders have a wide range of causes and, because of the potential for chronic back pain and disability, an accurate diagnosis is essential. The most frequent cause of pain in facet joints is osteoarthritis, which can be assessed at radiography, CT, or MRI. Ganglion and synovial cysts of the facet joints can cause compressive symptoms of adjacent structures, especially radiculopathy, lower back pain, and sensory or motor deficits. In ankylosing spondylitis, imaging findings of the facet joints are useful not only for diagnosis but also for monitoring structural changes. In septic arthritis of the facet joints, an early diagnosis at MRI is essential. Gout and metabolic diseases are best evaluated at dual-energy CT, which allows the depiction of crystals. Traumatic dislocations of facet joints are usually unstable injuries that require internal reduction, fixation, and fusion and can be well assessed at CT with three-dimensional reconstructions. Facet joint neoplasms like osteoid osteoma, plasmacytoma, tenosynovial giant cell tumor, and osteochondroma are best evaluated at CT or MRI. The authors provide an overview of key imaging features of the most common facet joint disorders along with anatomic tips and illustrative cases. Acknowledging key imaging findings for the differential diagnosis of facet joint disorders plays a crucial role in the diagnostic accuracy and proper treatment approach for such entities. Online supplemental material is available for this article. ©RSNA, 2021.

The development of the intercondylar notch in the pediatric population.

BACKGROUND: Anterior cruciate ligament (ACL) repair is increasing in frequency in younger children. Recognition of the normal development of the intercondylar notch is important for successful ACL graft placement, allowing surgeons to better understand the anatomy and risk factors related to ACL tears and its reconstruction. The purpose of this study was to compile normative data on the intercondylar notch in the pediatric population with magnetic resonance imaging (MRI), emphasizing the differences between males and females. METHODS: In this retrospective study, musculoskeletal radiologists evaluated intercondylar notch width, bicondylar distance and notch width index (NWI). A total of 253 MRI examinations (130 males and 123 females between six and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. RESULTS: Intercondylar notch width increased up to 10 years of age in females and 11 years of age in males, with relative stabilization up to 13 years in girls and 14 years in boys and a slight reduction in values at subsequent ages. Bicondylar distance showed significant progressive growth with age in both sexes. NWI showed a discrete and homogenous reduction with age in both sexes. CONCLUSION: Intercondylar notch width interrupts its growth around 10-11 years of age, with relative stabilization up to 13-14 years and a slight reduction in dimensions in subsequent ages. This growth pattern resembles the development of the ACL area observed in recent studies.

Varying the Order of Combinations of Single- and Multi-Joint Exercises Differentially Affects Resistance Training Adaptations.

Brandão, L, de Salles Painelli, V, Lasevicius, T, Silva-Batista, C, Brendon, H, Schoenfeld, BJ, Aihara, AY, Cardoso, FN, de Almeida Peres, B, and Teixeira, EL. Varying the order of combinations of single- and multi-joint exercises differentially affects resistance training adaptations. J Strength Cond Res 34(5): 1254-1263, 2020-Our study aimed to compare the effects of multi-joint (MJ) and single-joint (SJ) exercises, either isolated or in combination, and in different orders, on cross-sectional area (CSA) of the pectoralis major (PM) and different heads of the triceps brachii (TB), as well as on the one-repetition maximum (1-RM) in the bench press and lying barbell triceps press. Forty-three young men were randomly assigned to one of 4 possible RT protocols: barbell bench press plus lying barbell triceps press (MJ + SJ, n = 12); lying barbell triceps press plus barbell bench press (SJ + MJ, n = 10); barbell bench press (MJ, n = 10); or lying barbell triceps press (SJ, n = 11). Results showed significant within-group increases in 1-RM bench press for MJ, MJ + SJ, and SJ + MJ but not for SJ. Conversely, significantly greater within-group increases in elbow extension 1-RM were noted for SJ, MJ + SJ, and SJ + MJ but not for MJ. Significantly greater increases in PM CSA were observed for MJ, MJ + SJ, and SJ + MJ compared with SJ. Significant increases in TB CSA were noted for SJ, MJ + SJ, and SJ + MJ, but not for MJ, without observed between-group differences. Individual analysis of TB heads showed significantly greater CSA increases in the lateral head for MJ, MJ + SJ, and SJ + MJ compared with SJ. Alternatively, significantly greater increases in the long head were observed for SJ, MJ + SJ, and SJ + MJ compared with MJ. CSA increases for the medial head were statistically similar between conditions. Our findings indicate that muscular adaptations are differentially affected by performance of MJ and SJ exercises.

Radiological findings of fibrocartilaginous coalition of the third tarsometatarsal joint: a retrospective cross-sectional study with computed tomography and magnetic resonance imaging.

BACKGROUND: Fibrocartilaginous coalition of the third tarsometatarsal joint has been indicated as an extremely rare form of tarsal coalition in the radiological literature, and most articles concerned with tarsal coalition do not mention involvement of this joint. Only two reports written in the English language that approach this subject were found, an orthopedic report and an anthropological report. PURPOSE: To evaluate the prevalence of this finding and discuss and illustrate the radiological characteristics of this coalition. MATERIAL AND METHODS: A retrospective analysis of 614 computed tomography or magnetic resonance imaging scans of the ankle and/or foot, acquired at a health service within a period of three months, was performed to assess the prevalence of this coalition. RESULTS: Of the examinations characterized as valid for analysis for the purposes of the study, 17 cases compatible with fibrocartilaginous coalition of the third tarsometatarsal joint were found, thus indicating an involvement of approximately 2.97% of the examined feet. CONCLUSION: Our radiological findings are typical, and the prevalence found in this study was statistically significant, being similar to that described in the anthropological report (3.2%-6.8%).

Radiography, CT, and MRI of Hip and Lower Limb Disorders in Children and Adolescents.

Infants and children are vulnerable to congenital and developmental hip and lower extremity disorders. These disorders have diverse causes in pediatric patients, and owing to potential related complications that can lead to degenerative disease in adulthood, an accurate diagnosis is essential. A common disease is developmental dysplasia of the hip, which affects nearly 1% of newborns. This condition is best evaluated with US and conventional radiography. Slipped capital femoral epiphysis affects approximately 0.01% of young teenagers and is initially evaluated with radiography. Femoroacetabular impingement is a risk factor for early osteoarthritis and can be assessed with radiography, CT, or MRI. Limb length discrepancy is defined as a greater than 2-cm difference in length between paired bilateral lower extremities. There are several methods of measuring this difference, and the use of an accurate imaging modality is essential for treatment. Developmental bowing is a physiologic condition involving varus angulation of the knee and is best evaluated by using conventional radiography. Blount disease is a progressive pathologic genu varum centered at the tibia; the three subtypes are infantile, juvenile, and adolescent. In- and out-toeing disorders are caused by abnormal tibial and femoral torsion that usually self-corrects during lower limb growth. The ability to recognize these conditions is essential for differentiating those that will resolve spontaneously versus those that will require treatment. The imaging features of congenital and developmental hip and lower extremity disorders are reviewed, with emphasis on diagnosis, radiologic assessment, associated findings, and classification. ©RSNA, 2019.

The development of the anterior cruciate ligament in the paediatric population.

PURPOSE: The aim of this study was to retrospectively compile normative data on the anterior cruciate ligament (ACL) in the paediatric population with magnetic resonance imaging, emphasizing the differences between men and women. METHODS: In this retrospective study, musculoskeletal radiologists evaluated length, area, coronal and sagittal inclination of the ACL and inclination of the intercondylar notch. A total of 253 MR examinations (130 males and 123 females between 6 and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. RESULTS: ACL length showed significant progressive growth (p < 0.001) with age in men and women, without characterization of growth peaks. ACL area in women showed more pronounced growth up to 11 years, stabilized from 11 to 14 years and then sustained a slight reduction. In men, ACL area showed more pronounced growth up to 12 years, stabilized from 12 to 15 years and then sustained slight reduction. Coronal and sagittal inclination of the ACL showed a significant progressive increase (p < 0.001) with age in both sexes, progressively verticalizing. The intercondylar roof inclination angle showed significant progressive reduction (p < 0.001) with age in both sexes. CONCLUSION: The area of the ACL does not accompany skeletal maturation, interrupting its growth around 11-12 years. Progressive verticalization of the ACL as well as of the intercondylar notch roof in the evaluated ages was also observed. The clinical relevance of this study is that the ACL presents different angular and morphologic changes during growth in the paediatric population. Since ACL repair is now being performed on younger children, recognition of the normal developmental changes of the ACL is of utmost importance for successful ACL graft placement. LEVEL OF EVIDENCE: III.

Different Patterns in Muscular Strength and Hypertrophy Adaptations in Untrained Individuals Undergoing Nonperiodized and Periodized Strength Regimens.

De Souza, EO, Tricoli, V, Rauch, J, Alvarez, MR, Laurentino, G, Aihara, AY, Cardoso, FN, Roschel, H, and Ugrinowitsch, C. Different patterns in muscular strength and hypertrophy adaptations in untrained individuals undergoing non-periodized and periodized strength regimens. J Strength Cond Res 32(5): 1238-1244, 2018-This study investigated the effects of nonperiodized (NP), traditional periodization (TP), and daily undulating periodization (UP) regimens on muscle strength and hypertrophy in untrained individuals. Thirty-three recreationally active males were randomly divided into 4 groups: NP: n = 8; TP: n = 9; UP: n = 8, and control group (C): n = 8. Experimental groups underwent a 12-week strength training program consisting of 2 sessions per week. Muscle strength and quadriceps cross-sectional area (QCSA) were assessed at baseline, 6 weeks (i.e., mid-point) and after 12 weeks. All training groups increased squat 1RM from pre to 6 weeks mid (NP: 17.02%, TP: 7.7%, and UP: 12.9%, p ≤ 0.002) and pre to post 12 weeks (NP: 19.5%, TP: 17.9%, and UP: 20.4%, p ≤ 0.0001). Traditional periodization was the only group that increased squat 1RM from 6 weeks mid to 12-week period (9.4%, p ≤ 0.008). All training groups increased QCSA from pre to 6 weeks mid (NP: 5.1%, TP: 4.6%, and UP: 5.3%, p ≤ 0.0006) and from pre to post 12 weeks (NP: 8.1%, TP: 11.3%, and UP: 8.7%, p ≤ 0.0001). From 6 weeks mid to 12-week period, TP and UP were the only groups that increased QCSA (6.4 and 3.7%, p ≤ 0.02). There were no significant changes for all dependent variables in C group across the time (p ≥ 0.05). In conclusion, our results demonstrated similar training-induced adaptations after 12 weeks of NP and periodized regimens. However, our findings suggest that in the latter half of the study (i.e., after the initial 6 weeks), the periodized regimens elicited greater rates of muscular adaptations compared with NP regimens. Strength coaches and practitioners should be aware that periodized regimens might be advantageous at latter stages of training even for untrained individuals.

Femoral Component Axial Rotation in the Gap-Balancing Approach to Total Knee Arthroplasty: Measurement by Computed Tomography.

BACKGROUND: Rotational malalignment of total knee arthroplasty (TKA) is a potential cause for revision surgery; therefore, it is important to have valid criteria for evaluation of normal component rotational alignment. Because computed tomography (CT) is considered the most accurate method to assess the rotational alignment of prosthetic components, the objectives in this study were define the femoral component (FC) rotation by measuring the posterior condylar angle (PCA) and the condylar twist angle (CTA) in a patient population that underwent gap-balancing TKA; determine the reliability of the FC rotation by using these measurements; evaluate the inter-relationship between the PCA and CTA; and finally evaluate the frequency and agreement in identification of the medial epicondyle sulcus (MES). METHODS AND RESULTS: In this retrospective study, 2 radiologists examined 50 CT scans. Mean PCA values of -2.26° and -2.56° (internal rotation) and CTA values of -5.54° and -6.28° (internal rotation) were attained by 2 observers with a higher interobserver concordance for the PCA. Both measurements were considered to be reliable. There was moderate interobserver agreement for MES identification, with the MES present in 64% and 78% of patients, as identified by 2 observers. CONCLUSION: Mean FC rotation values as evaluated by PCA were -2.26° and -2.56° and as evaluated by CTA were -5.54° and -6.28°. PCA and CTA measurement by CT is reliable; however, the use of PCA is preferable because of the higher observer concordance. PCA can be inferred by subtracting 3° or 4° from the CTA. MES was identified in 64% and 78% of patients, with only moderate interobserver agreement.