Finding the Optimal Resistance Training Intensity for Your Bones: Protocol for a Randomized Controlled Trial.

OBJECTIVE: The purpose of this trial is to evaluate the effect of twice-weekly, moderate-to-high intensity progressive resistance training (PRT) for 1 year on lumbar spine bone mineral density (BMD) in individuals with low BMD, compared to attention control. Secondary analyses will examine if resistance training improves other health outcomes; if high intensity is more effective than moderate intensity resistance training for all outcomes; the cost of intervention versus benefit; the willingness to pay; and harms. METHODS: For this study, 324 men or postmenopausal women aged ≥50 years with a femoral neck, total hip, or lumbar spine BMD T-score of ≤-1, or a Fracture Risk Assessment Tool probability of ≥20% for major osteoporotic fracture or ≥ 3% for hip fracture are being recruited to participate in a randomized controlled trial with 1:1:1 randomization. Participants will be stratified by site (3 centers) to twice-weekly, supervised PRT at moderate intensity (about 10 repetitions maximum), to high intensity PRT (≤6 repetitions maximum), or to a home posture and balance exercise program (attention control) for 1 year (resistance training to comparator allocation ratio of 2:1). The primary outcome is lumbar spine BMD via dual-energy X-ray absorptiometry. Secondary outcomes include trabecular bone score, proximal femur and total hip BMD and structure, bone-free and appendicular lean mass, physical functioning, falls, fractures, glucose metabolism, cost per life-year gained, adverse events, and quality of life. Between-group differences will be tested in intention-to-treat and per-protocol analyses using analysis of covariance, chi-square tests, or negative binomial or logistic regression, adjusting for site and baseline values. IMPACT: The Finding the Optimal Resistance Training Intensity For Your Bones trial will support decision making on resistance training for people at risk of fracture.

Performance of ChatGPT on a Radiology Board-style Examination: Insights into Current Strengths and Limitations.

Background ChatGPT is a powerful artificial intelligence large language model with great potential as a tool in medical practice and education, but its performance in radiology remains unclear. Purpose To assess the performance of ChatGPT on radiology board-style examination questions without images and to explore its strengths and limitations. Materials and Methods In this exploratory prospective study performed from February 25 to March 3, 2023, 150 multiple-choice questions designed to match the style, content, and difficulty of the Canadian Royal College and American Board of Radiology examinations were grouped by question type (lower-order [recall, understanding] and higher-order [apply, analyze, synthesize] thinking) and topic (physics, clinical). The higher-order thinking questions were further subclassified by type (description of imaging findings, clinical management, application of concepts, calculation and classification, disease associations). ChatGPT performance was evaluated overall, by question type, and by topic. Confidence of language in responses was assessed. Univariable analysis was performed. Results ChatGPT answered 69% of questions correctly (104 of 150). The model performed better on questions requiring lower-order thinking (84%, 51 of 61) than on those requiring higher-order thinking (60%, 53 of 89) (P = .002). When compared with lower-order questions, the model performed worse on questions involving description of imaging findings (61%, 28 of 46; P = .04), calculation and classification (25%, two of eight; P = .01), and application of concepts (30%, three of 10; P = .01). ChatGPT performed as well on higher-order clinical management questions (89%, 16 of 18) as on lower-order questions (P = .88). It performed worse on physics questions (40%, six of 15) than on clinical questions (73%, 98 of 135) (P = .02). ChatGPT used confident language consistently, even when incorrect (100%, 46 of 46). Conclusion Despite no radiology-specific pretraining, ChatGPT nearly passed a radiology board-style examination without images; it performed well on lower-order thinking questions and clinical management questions but struggled with higher-order thinking questions involving description of imaging findings, calculation and classification, and application of concepts. © RSNA, 2023 See also the editorial by Lourenco et al and the article by Bhayana et al in this issue.

GPT-4 in Radiology: Improvements in Advanced Reasoning.

Supplemental material is available for this article. See also the article by Bhayana et al and the editorial by Lourenco et al in this issue.

Acromioclavicular Joint Injuries in Professional Ice Hockey Players: Epidemiologic and MRI Findings and Association With Return to Play.

BACKGROUND: Acromioclavicular joint (ACJ) injuries are common in ice hockey players and are traditionally evaluated with conventional radiography, which has recognized limitations in the accurate characterization of the spectrum of soft tissue injuries and severity/grade of injury sustained. PURPOSE: To evaluate the epidemiologic, clinical, and magnetic resonance imaging (MRI) findings in professional ice hockey players who have sustained acute ACJ injuries. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective review was performed of professional National Hockey League (NHL) players referred for MRI evaluation of acute ACJ injuries. All MRI scans were assessed for status of the ACJ, ligamentous stabilizers, and surrounding musculature. MRI-based overall grade of ACJ injury (modified Rockwood grade 1-6) was assigned to each case. Data regarding mechanism of injury, player handedness, clinical features, and return to play were evaluated. RESULTS: Overall, 24 MRI examinations of acute ACJ injuries (23 patients; mean age, 24 years) were reviewed. We found that 50% of injuries were sustained during the first period of play, and in 75% of cases, injuries involved the same side as player shooting handedness. Analysis of MRI scans revealed 29% (7/24) grade 1 ACJ injuries, 46% (11/24) grade 2 injuries, 21% (5/24) grade 3 injuries, and 4% (1/24) grade 5 injuries. Trapezius muscle strains were seen in 79% and deltoid muscle strain in 50% of cases. Nonoperative management was used for 23 injuries; 1 patient (grade 5 injury) underwent acute reconstructive surgery. All players successfully returned to professional NHL competition. Excluding cases with additional injuries or surgery (n = 3) or convalescence extending into the offseason (n = 3), we found that the mean return to play was 21.4 days (7.2 games missed). No statistically significant difference was observed in return to play between nonoperatively treated grade 3 injuries (mean, 28.3 days) and grade 1 or 2 injuries (mean, 20.1 days). However, grade 3 injuries were associated with a greater number of NHL scheduled games missed (mean, 12.7) compared with lower grade injuries (mean, 6.1) (P = .027). CONCLUSION: The spectrum of pathology and grading of acute ACJ injuries sustained in professional ice hockey can be accurately assessed with MRI; the majority of injuries observed in this study were low grade (grades 1 and 2). Although grade 3 injuries were associated with a greater number of games missed, similar return-to-play results were observed between nonoperatively treated grade 3 and grade 1 or 2 ACJ injuries.

Are osteoporotic vertebral fractures or forward head posture associated with performance-based measures of balance and mobility?

The main objective of this study was to explore whether vertebral fracture characteristics or posture is independently associated with physical performance. Posture was significantly associated with physical performance but fracture characteristics were not, suggesting posture should be the focus of physical performance variance. PURPOSE: The main objective of this study was to explore whether vertebral fracture characteristics (number, severity, location) or occiput-to-wall distance (OWD) is independently associated with physical performance. METHODS: This was a secondary data analysis using baseline data from a randomized controlled trial, of community-dwelling women aged 65 years and older with a suspected vertebral fragility fracture. Lateral thoracic and lumbar spine radiographs were used to determine the number, location, and severity of fracture. The dependent variables were timed up and go (TUG), five times sit-to-stand, four-meter walk, and step test. The independent variables were number, severity, location of fracture, and OWD. Pain during movement and age were covariates. Multivariable regression analyses determined the association between each of the dependent and independent variables. RESULTS: Participants' (n = 158) mean (standard deviation [SD]) age was 75.9 (6.5) years. They had a mean (SD) BMI, OWD, and number of fractures of 26.7 (5.3) kg/m2, 5.7 (4.6) cm, and 2.2 (1.8), respectively. OWD was independently associated with TUG (estimated coefficient [B] = 0.29, 95% confidence interval [CI] = 0.16, 0.42), five times sit-to-stand (B = 0.33, 95% CI = 0.12, 0.55), four-meter walk (B = 0.09, 95% CI = 0.05, 0.13), and step test (B = - 0.36, 95% CI = - 0.50, - 0.23) in the unadjusted model. OWD was independently associated with TUG (B = 0.25, 95% CI = 0.12, 0.38), five times sit-to-stand (B = 0.29, 95% CI = 0.07, 0.50), four-meter walk (B = 0.08, 95% CI = 0.03, 0.12), and step test (B = - 0.22, 95% CI = - 0.47, - 0.19) in the adjusted model. CONCLUSION: OWD was significantly associated with physical performance but fracture characteristics were not. These analyses were exploratory and require replication in future studies.

Exploring the association between number, severity, location of fracture, and occiput-to-wall distance.

This study of women with a suspected vertebral fracture determined the association between vertebral fracture characteristics and posture. The number of fractures was associated with posture. Severity of fracture was associated with posture when adjusting for pain. Fracture characteristics explain some variability in posture in women with a suspected vertebral fracture. PURPOSE: Osteoporotic vertebral fractures are associated with increased morbidity and mortality. An accumulation of vertebral fractures may lead to forward head posture, which has been independently associated with mortality. It is unclear how fracture characteristics, including the number, severity, and location of fracture, contribute to occiput-to-wall distance (OWD). METHODS: This was a cross-sectional secondary data analysis using baseline data from a randomized controlled trial, in community-dwelling women aged 65 years and older with a suspected vertebral fragility fracture. Lateral thoracic and lumbar spine radiographs were used to determine the number, location, and severity of fracture. Occiput-to-wall distance (OWD) was used to assess forward head posture. Pain during movement (0-10 scale) and age were considered as confounding variables. Multivariable regression models were used to evaluate relationships between fracture variables and OWD. RESULTS: Participants (n = 158) were of mean age 75.9 (SD 6.5) years with a mean (SD) BMI = 26.7 (5.3) kg/m2, OWD = 5.7 (4.6) cm, and number of fractures = 2.4 (2.4). In unadjusted analyses, the number of fractures (B = 0.82, 95% CI = 0.04, 1.59) was associated with OWD. When adjusting for pain, severity of fractures (B = 1.08, 95% CI = 0.001, 2.15) was independently associated with OWD. Location was not associated with OWD in any of the models. CONCLUSIONS: The number of fractures was significantly associated with OWD in the unadjusted model, explaining more of the variability in OWD than other fracture characteristics. Severity of fracture was associated with OWD in the adjusted model. However, pain may confound the relationship between OWD and fracture characteristics.

A Case of Posterior Tibial Nerve Injury After Arthroscopic Calcaneoplasty.

We report the first case of distal posterior tibial nerve injury after arthroscopic calcaneoplasty. A 59-year-old male had undergone right arthroscopic calcaneoplasty to treat retrocalcaneal bursitis secondary to a Haglund's deformity. The patient complained of numbness in his right foot immediately after the procedure. Two years later and after numerous assessments and investigations, a lateral plantar nerve and medial calcaneal nerve lesion was diagnosed. In the operating room, the presence of an iatrogenic lesion to the distal right lateral plantar nerve (neuroma incontinuity involving 20% of the nerve) and the medial calcaneal nerve (complete avulsion) was confirmed. The tarsal tunnel was decompressed, and both the medial and the lateral plantar nerve were neurolyzed under magnification. To the best of our knowledge, our case report is the first to describe iatrogenic posterior tibial nerve injury after arthroscopic calcaneoplasty. It is significant because this complication can hopefully be avoided in the future with careful planning and creation of arthroscopic ports and treated appropriately with early referral to a nerve specialist if the patient's symptoms do not improve within 3 months.

Low prevalence of unexpected popliteal DVT detected on routine MRI assessment of the knee.

OBJECTIVE: The purpose of this study was to document the appearance and determine the prevalence of findings suspicious for popliteal vein thrombosis on magnetic resonance (MR) assessment of the knee joint. METHODS: A total of 2888 MR examinations were retrospectively reviewed and classified as illustrating either normal appearing popliteal vein or findings suspicious for popliteal vein thrombosis. RESULTS: A total of 2879 MR studies were assessed as having a normal appearing popliteal vein. Nine studies illustrated findings suspicious for popliteal vein thrombosis. CONCLUSION: Although the prevalence of MR findings is low (0.3%), our findings reiterate the need to interrogate the popliteal vein for evidence of thrombosis.

Build better bones with exercise: protocol for a feasibility study of a multicenter randomized controlled trial of 12 months of home exercise in women with a vertebral fracture.

BACKGROUND: Our goal is to conduct a multicenter randomized controlled trial (RCT) to investigate whether exercise can reduce incident fractures compared with no intervention among women aged ≥65 years with a vertebral fracture. OBJECTIVES: This pilot study will determine the feasibility of recruitment, retention, and adherence for the proposed trial. DESIGN: The proposed RCT will be a pilot feasibility study with 1:1 randomization to exercise or attentional control groups. SETTING: Five Canadian sites (1 community hospital partnered with an academic center and 4 academic hospitals or centers affiliated with an academic center) and 2 Australian centers (1 academic hospital and 1 center for community primary care, geriatric, and rehabilitation services). PARTICIPANTS: One hundred sixty women aged ≥65 years with vertebral fracture at 5 Canadian and 2 Australian centers will be recruited. INTERVENTION: The Build Better Bones With Exercise (B3E) intervention includes exercise and behavioral counseling, delivered by a physical therapist in 6 home visits over 8 months, and monthly calls; participants are to exercise ≥3 times weekly. Controls will receive equal attention. MEASUREMENTS: Primary outcomes will include recruitment, retention, and adherence. Adherence to exercise will be assessed via calendar diary. Secondary outcomes will include physical function (lower extremity strength, mobility, and balance), posture, and falls. Additional secondary outcomes will include quality of life, pain, fall self-efficacy, behavior change variables, intervention cost, fractures, and adverse events. Analyses of feasibility objectives will be descriptive or based on estimates with 95% confidence intervals, where feasibility will be assessed relative to a priori criteria. Differences in secondary outcomes will be evaluated in intention-to-treat analyses via independent Student t tests, chi-square tests, or logistic regression. The Bonferroni method will be used to adjust the level of significance for secondary outcomes so the overall alpha level is .05. LIMITATIONS: No assessment of bone mineral density will be conducted. The proposed definitive trial will require a large sample size. CONCLUSIONS: The viability of a large-scale exercise trial in women with vertebral fractures will be evaluated, as well as the effects of a home exercise program on important secondary outcomes.

Musculotendinous architecture of pathological supraspinatus: a pilot in vivo ultrasonography study.

Architectural changes associated with tendon tears of the supraspinatus muscle (SP) have not been thoroughly investigated in vivo with the muscle in relaxed and contracted states. The purpose of this study was to quantify the geometric properties within the distinct regions of SP in subjects with full-thickness tendon tears using an ultrasound protocol previously developed in our laboratory, and to compare findings with age/gender matched normal controls. Twelve SP from eight participants (6 male/2 female), mean age 57 ± 6.0 years, were investigated. Muscle geometric properties of the anterior region (middle and deep parts) and posterior region (deep part) were measured using image analysis software. Along with whole muscle thickness, fiber bundle length (FBL) and pennation angle (PA) were computed for architecturally distinct regions and/or parts. Pathologic SP was categorized according to the extent of the tear in the tendon (with or without retraction). In the anterior region, mean FBL of the pathologic SP was similar with normal controls; however, mean PA was significantly smaller in pathologic SP with retraction compared with normal controls, in the contracted state (P < 0.05). Mean FBL in the posterior region in both relaxed and contracted states was significantly shorter in the pathologic SP with retraction compared with normal controls (P < 0.05). Findings suggest FBL changes associated with tendon pathology vary between the distinct regions, and PA changes are related to whether there is retraction of the tendon. The ultrasound protocol may provide important information on architectural changes that may assist in decision making and surgical planning.

Current imaging of the rotator cuff.

Rotator cuff pathology is a common cause of shoulder pain, and imaging plays a major role in the management of shoulder problems. General radiography may be useful as an initial screening test particularly in trauma and arthritis. Musculoskeletal ultrasound and magnetic resonance imaging are the most suitable modalities for the investigation of the rotator cuff, having high sensitivities and specificities for full-thickness tears. Musculoskeletal ultrasound and magnetic resonance imaging are less accurate in the detection of partial-thickness tears with greater observer variability. This article reviews the normal and pathologic imaging features of the rotator cuff and highlights the potential usefulness and limitations of various imaging modalities in the assessment of the tendon and the potential impact of imaging findings on clinical patient care.

Limitations of single slice dynamic contrast enhanced MR in pharmacokinetic modeling of bone sarcomas.

BACKGROUND: Single slice dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) appears to provide perfusion data about sarcomas in vivo that correlate with tumor necrosis on equivalent pathological sections. However, sarcomas are heterogeneous and therefore single slice DCE-MRI may not correlate with total tumor necrosis. PURPOSE: To determine whether changes in pharmacokinetic modeling of DCE-MRI, during chemotherapy for primary bone sarcomas correlated with histological measures of total tumor necrosis. MATERIAL AND METHODS: Twelve patients with appendicular primary bone sarcomas were included in the study. Each patient had DCE-MRI before, and after completion, of pre-operative chemotherapy. The mean arterial slope (A), endothelial permeability coefficient (K(trans)), and extravascular extracellular volume (V(e)) were derived from each data set using a modified two compartment pharmacokinetic model. Total tumor necrosis rates were compared with changes in A, K(trans), and V(e). RESULTS: Six patients had total tumor necrosis of >or=90% and six had a measure of <90%. The median percentage changes in A, K(trans), and V(e) for the >or=90% necrosis group were -52.5% (-83 to 6), -66% (-82 to 26), and 23.5% (-26 to 40), respectively. For the <90% necrosis group, A = - 35% (-75 to 132), K(trans)= - 53 (-66 to 149) and V(e)= - 14.5% (-42 to 40). One patient with >90% necrosis had increases in all three measures. Comparison of the two groups generated P-values of 0.699 for A, 0.18 for K(trans), and 0.31 for V(e). CONCLUSION: There was no statistically significant correlation between changes in pharmacokinetic perfusion parameters and total tumor necrosis. When using single slice DCE-MRI heterogeneous histology of primary bone sarcomas and repair mediated angiogenesis might both be confounding factors.

Accessory muscles: anatomy, symptoms, and radiologic evaluation.

A wide array of supernumerary and accessory musculature has been described in the anatomic, surgical, and radiology literature. In the vast majority of cases, accessory muscles are asymptomatic and represent incidental findings at surgery or imaging. In some cases, however, accessory muscles may produce clinical symptoms. These symptoms may be related to a palpable swelling or may be the result of mass effect on neurovascular structures, typically in fibro-osseous tunnels. In cases in which an obvious cause for such symptoms is not evident, recognition and careful evaluation of accessory muscles may aid in diagnosis and treatment.

Lipofibromatous hamartoma of the upper extremity: a review of the radiologic findings for 15 patients.

OBJECTIVE: The purpose of this study was to analyze the radiologic characteristics of lipofibromatous hamartomas affecting upper limb peripheral nerves. CONCLUSION: Although there are pathognomonic features that characterize lipofibromatous hamartoma on MRI, the range of appearances is broad. Sonography appears to show equally characteristic features and may be a useful tool for assessing this condition.

Imaging of the Achilles tendon.

The Achilles tendon is the most commonly injured tendon in the foot and ankle; injuries commonly are related to sports/athletic activities. Imaging modalities that are used most commonly in the diagnostic assessment of the Achilles tendon include conventional radiography, ultrasonography, and MRI. This article reviews the normal and pathologic imaging features of the Achilles tendon, and highlights the potential usefulness and limitations of various imaging techniques in the noninvasive assessment of the tendon and the potential impact of imaging findings on clinical patient care.

Long-term ultrasonographic features of the Achilles tendon after rupture.

PURPOSE: To assess the long-term ultrasonographic appearance of rupture of the Achilles tendon. SUBJECTS AND METHODS: We examined 70 patients at an average of 63 months (range 10-120 months) after rupture of the Achilles tendon. We assessed the patient's contralateral tendon and also performed ultrasonography on the Achilles tendon of 70 age- and sex-matched controls. We recorded the maximum transverse anteroposterior diameter, the presence of intratendinous alterations, and the presence of intratendinous calcification. RESULTS: The average maximum anteroposterior diameter of the ruptured tendon was 11.7 mm (SD = 2.10). The patients' normal tendons measured an average of 5.4 mm (SD = 0.9), and there was an average measure of 4.9 mm (SD = 0.5) (p = 0.0001) in the controls. There was no difference in the maximum anteroposterior diameter of the ruptured tendon depending on the method of treatment (conservative, open repair, percutaneous repair). Seventeen patients exhibited areas of hypoechogenicity in their ruptured tendon, two patients had areas of hypoechogenicity in their unruptured contralateral tendon, and 10 patients had calcification in their ruptured tendon. CONCLUSION: The anteroposterior diameter of the ruptured tendon was significantly greater than the nonruptured contralateral. However, when compared with a group of individually age- and sex-matched controls, the patients' contralateral tendons had significantly greater maximum anteroposterior diameter and had a greater prevalence of intratendinous alterations. This difference may represent a background of subclinical tendinopathy that may predispose to rupture.