Faculty Bibliography

Knee MRI plays a central role in musculoskeletal diagnostics but has traditionally been associated with relatively long acquisition times. Recent technological advances have fundamentally changed this paradigm. Parallel imaging (PI), simultaneous multi-slice acquisition (SMS), compressed sensing (CS), and combinations thereof have substantially reduced scan times without compromising diagnostic image quality. The introduction of deep learning (DL)-based reconstruction further elevates this transformative breakthrough, as it can reconstruct high-quality diagnostic MR images at higher acceleration factors, where conventional image reconstruction methods have traditionally struggled to succeed. Sixfold PIxSMS-accelerated DL protocols have demonstrated excellent diagnostic performance and image quality, allowing comprehensive knee MRI examinations to be completed in under five minutes. Accelerated three-dimensional (3D) TSE techniques, such as CAIPIRINHA-accelerated SPACE sequences, further expand the potential of knee MRI by enabling high-resolution isotropic 3D imaging at acquisition times that are increasingly practical for routine clinical use. Ongoing improvements in DL-based reconstruction and denoising may soon bridge the remaining gap, promising to enable the acquisition of isotropic 3D datasets with multiple contrasts within minutes. Beyond technical acceleration, the successful implementation of fast MRI requires careful workflow optimization and consideration of architectural and economic factors. This review outlines the technical principles underlying modern acceleration strategies, summarizes evidence from validation studies, discusses practical aspects of clinical implementation and protocol optimization, and highlights future opportunities and challenges.

ABSTRACT/UNASSIGNED:Musculoskeletal magnetic resonance imaging has evolved substantially, driven by advances in hardware, image acquisition, and reconstruction techniques. Improvements in gradient performance and dedicated radiofrequency coils have enhanced spatial resolution and scan efficiency across field strengths. Image acceleration strategies, including parallel imaging, simultaneous multislice acquisition, and compressed sensing, now enable high-quality two-dimensional and three-dimensional magnetic resonance imaging with markedly reduced examination times and facilitate the time-neutral incorporation of advanced metal artifact reduction techniques into clinical magnetic resonance imaging protocols. ABSTRACT/UNASSIGNED:Deep learning-based reconstruction and super-resolution augmentation methods have further expanded achievable acceleration and image quality. Emerging techniques such as synthetic magnetic resonance imaging, magnetic resonance neurography, kinematic magnetic resonance imaging, and zero echo time magnetic resonance imaging expand the capabilities of musculoskeletal magnetic resonance imaging. At the same time, renewed interest in low-field magnetic resonance imaging provides intriguing opportunities to improve accessibility and sustainability. Ultra-high field magnetic resonance imaging provides unprecedented spatial resolution and quantitative insights in selected applications. These developments are redefining musculoskeletal magnetic resonance imaging practice and broadening its clinical value.

Radiography is an excellent first-line imaging technique for a wide range of conditions. However, there is insufficient evidence-based clinical guidance for ordering radiographic examinations in certain low-yield anatomic sites. To address this issue, a three-round modified Delphi consensus study was performed with a multidisciplinary, multi-institutional expert panel to determine the appropriate utilization of radiography at 12 often low-yield anatomic sites. The expert panel comprised 34 subspecialty faculty members (16 radiologists, nine emergency medicine physicians, four orthopedic surgeons, and five otolaryngology surgeons) from 21 academic centers. They evaluated 12 anatomic sites: rib, scapula, sacrum, coccyx, sternum, sternoclavicular joint, nasal bone, mandible, facial bones, sinuses, neck soft tissue, and skull. A structured literature review across three databases was conducted to assess the utilization and diagnostic test characteristics of radiography for each anatomic site. Teams drafted consensus statements and supporting text for their respective sites and submitted these statements to the panel for iterative rounds of anonymized voting. All 58 submitted statements achieved consensus by the end of round 3 and were endorsed by six major American medical societies. This study established expert consensus recommendations for the appropriate utilization of radiography at 12 anatomic sites through a multidisciplinary and multi-institutional deliberative process.

INTRODUCTION/BACKGROUND:Press-fit acetabular components achieve long-term fixation through osseointegration, yet the extent of bone ingrowth necessary for durable stability in well-functioning implants remains unclear. Postmortem retrievals provide a unique opportunity to directly assess the bone-cup interface in clinically successful total hip arthroplasties (THAs). This study evaluated osseointegration and biomechanical fixation strength in deceased-donor acetabular components to better define the characteristics of stable long-term fixation. METHODS:Cadaver pelvis specimens containing uncemented THAs from a single institution were evaluated. There were 29 acetabular components that underwent axial pull-out testing using a universal testing machine. A total of seven of these were additionally processed for histologic evaluation, including dehydration, acrylic embedding, thin-sectioning, staining, and digital imaging. Osseointegration was quantified by bone-area fraction occupancy (%BAFO), representing the proportion of bone occupying the porous thread spaces of the cup. RESULTS:All 29 specimens failed through fracture of the ilium rather than at the bone-cup interface, indicating that the mechanical integrity of the osseointegrated construct exceeded that of the surrounding bone under axial tension. Among the seven histologically analyzed components, %BAFO ranged from 4.2 to 27.0% (mean 15.1%), despite all implants being clinically stable at the time of death. There were no significant linear correlations observed between %BAFO and time implanted, fracture load, or body mass index. A significant quadratic relationship between %BAFO and age was identified, peaking near 81 years. CONCLUSIONS:Cementless acetabular components exhibited strong fixation despite modest osseointegration, with failure occurring through host bone on axial testing. Durable biological fixation appears achievable with limited, but mechanically favorable bone ingrowth.

Knee injuries are one of the most common complaints in sports medicine. Magnetic resonance imaging is an essential adjunct to clinical evaluation for many traumatic injuries and overuse conditions. Given the heavy use of knee magnetic resonance imaging, developing faster magnetic resonance imaging acquisition methods and deployment in clinical practice would be valuable. In this article, we illustrate a spectrum of knee abnormalities from our clinical practice, utilizing a recently developed, publicly available sub-5-minute knee magnetic resonance imaging protocol with super-resolution image reconstruction based on deep learning. We review common traumatic injuries and overuse conditions of the knee and illustrate cases with this novel fast knee magnetic resonance imaging protocol.

The past decade has witnessed remarkable advancements in musculoskeletal radiology, driven by increasing demand for medical imaging and rapid technological innovations. Contrary to early concerns about artificial intelligence (AI) replacing radiologists, AI has instead enhanced imaging capabilities, aiding in automated abnormality detection and workflow efficiency. MRI has benefited from acceleration techniques that significantly reduce scan times while maintaining high-quality imaging. In addition, novel MRI methodologies now support precise anatomic and quantitative imaging across a broad spectrum of field strengths. In CT, dual-energy and photon-counting technologies have expanded diagnostic possibilities for musculoskeletal applications. This review explores these key developments, examining their impact on clinical practice and the future trajectory of musculoskeletal radiology.

This article provides a practice-oriented overview of current concepts in rapid musculoskeletal MRI of central and peripheral joints, focusing on echo train optimization and the application of modern acceleration techniques. Parallel imaging, simultaneous multislice acquisition, and compressed sensing-based undersampling can be applied independently or in combination to expedite MRI of the joints. Clinically available three- to eightfold acceleration of two-dimensional (2D) and three-dimensional turbo spin-echo (TSE) pulse sequences enables comprehensive 5-10-minute MRI protocols of joints. This acceleration allows for the efficient integration of advanced metal artifact reduction techniques into clinical MRI protocols. When conventional image reconstruction techniques fail, clinically available deep learning-based image reconstruction and superresolution augmentation methods effectively reconstruct images from highly accelerated acquisitions. Together, moderate acceleration and advanced image reconstruction techniques provide high diagnostic image quality of heavily undersampled MRI data, enabling three- to sixfold accelerated 2D TSE MRI of multiple joints in 4-6 minutes. Recent studies indicate that specially designed and trained deep learning methods may achieve 10-fold accelerated musculoskeletal MRI, with acquisition times under 3 minutes. Although further research and data are necessary, these promising developments are poised to enhance the value of musculoskeletal MRI.

PURPOSE/OBJECTIVE:To develop expert consensus recommendations for patient selection and procedural techniques in cryoneurolysis for chronic pain management using a Delphi process. MATERIALS AND METHODS/METHODS:A panel of 22 international interventionists participated in a two-round Delphi process. Participants rated 42 statements on a 10-point Likert scale (1 = strongly disagree, 10 = strongly agree). Consensus was predefined as ≥ 75% of ratings ≥ 7. Descriptive statistics (n, mean ± SD, % ≥ 7) were calculated. RESULTS:High agreement supported cryoneurolysis for localized chronic pain refractory to conservative therapies (mean 8.55 ± 0.60; 100% ≥ 7) and cases with identifiable peripheral nerve targets (8.45 ± 0.74; 100% ≥ 7). Imaging guidance was deemed essential for nerve identification and probe placement (8.91 ± 0.29; 100% ≥ 7). The panel endorsed individualized freeze-thaw cycles to achieve Sunderland II injury (8.27 ± 0.83; 91% ≥ 7) and emphasized thorough patient education (9.0 ± 0.0; 100% ≥ 7). Experts recommended repeat cryoneurolysis within weeks if initial response was incomplete (8.64 ± 0.65; 100% ≥ 7) and alternative therapies after two unsuccessful sessions (8.36 ± 0.73; 95% ≥ 7). No consensus was reached on restricting treatment to a single anatomical region (5.82 ± 2.91; 50% ≥ 7) or routine prophylactic antibiotics (6.27 ± 2.57; 54% ≥ 7). CONCLUSION/CONCLUSIONS:This Delphi study establishes expert-derived consensus standards for cryoneurolysis, highlighting careful patient selection, mandatory imaging guidance, and flexible freeze protocols while identifying areas requiring further research.