Weight-bearing radiographs and cone-beam computed tomography examinations in adult acquired flatfoot deformity.

Background: Optimal characterization of Adult acquired flatfoot deformity (AAFD) on two-dimensional radiograph can be challenging. Weightbearing Cone Beam CT (CBCT) may improve characterization of the three-dimensional (3D) structural details of such dynamic deformity. We compared and validated AAFD measurements between weightbearing radiograph and weightbearing CBCT images.

Association Between Knee Anatomic Metrics and Biomechanics for Male Soldiers Landing With Load.

Background: Anterior cruciate ligament (ACL) injury is a military occupational hazard that may be attributed to an individual's knee biomechanics and joint anatomy. This study sought to determine if greater flexion when landing with load resulted in knee biomechanics thought to decrease ACL injury risk and whether knee biomechanics during landing relate to knee anatomic metrics.

Hypothesis: Anatomic metrics regarding the slope and concavity of the tibial plateau will exhibit a significant relation to the increased anterior shear force on the knee and decreased knee flexion posture during landing with body-borne load.

Motion compensation in extremity cone-beam computed tomography.

Objectives: To evaluate the improvement in extremity cone-beam computed tomography (CBCT) image quality in datasets with motion artifact using a motion compensation method based on maximizing image sharpness.

Methods: Following IRB approval, retrospective analysis of 308 CBCT scans of lower extremities was performed by a fellowship-trained musculoskeletal radiologist to identify images with moderate to severe motion artifact. Twenty-four scans of 22 patients (18 male, four female; mean, 32 years old, range, 21-74 years old) were chosen for inclusion.

Reliability of distal tibio-fibular syndesmotic instability measurements using weightbearing and non-weightbearing cone-beam CT.

Background: To investigate the reliability and reproducibility of syndesmosis measurements on weightbearing (WB) cone-beam computed tomography (CBCT) images and compare them with measurements obtained using non-weightbearing (NWB) images.

Methods: In this IRB-approved, retrospective study of 5 men and 9 women with prior ankle injuries, simultaneous WB and NWB CBCT scans were taken. A set of 21 syndesmosis measurements using WB and NWB images were performed by 3 independent observers.

Cone-beam CT measurements of distal tibio-fibular syndesmosis in asymptomatic uninjured ankles: does weight-bearing matter?

Objective: To evaluate the influence of weight-bearing (WB) load in standard axial ankle syndesmotic measurements using cone beam CT (CBCT) examination of asymptomatic uninjured ankles.

Materials And Methods: In this IRB approved, prospective study, patients with previous unilateral ankle fractures were recruited. We simultaneously scanned the injured ankles and asymptomatic contralateral ankles of 27 patients in both WB and NWB modes.

10-Min 3D Turbo Spin Echo MRI of the Knee in Children: Arthroscopy-Validated Accuracy for the Diagnosis of Internal Derangement.

Background: Ten-minute MRI of the pediatric knee can add value through increased cost-effectiveness and decreased sedation needs but requires validation of its clinical efficacy.

Purpose: To determine the arthroscopy-based diagnostic accuracy and interreader reliability of 10-min 3D Controlled Aliasing In Parallel Imaging Results In Higher Acceleration (CAIPIRINHA) turbo spin echo (TSE) MRI with two isotropic pulse sequences for the diagnosis of internal derangement in children with painful knee conditions.

Study Type: Prospective.

CAIPIRINHA-accelerated 10-min 3D TSE MRI of the ankle for the diagnosis of painful ankle conditions: Performance evaluation in 70 patients.

Objectives: To test the hypothesis that MRI of the ankle with a 10-min 3D CAIPIRINHA SPACE TSE protocol is at least equivalent for the detection of painful conditions when compared to a 20-min 2D TSE standard of reference protocol.

Methods: Following institutional review board approval and informed consent, 70 symptomatic subjects underwent 3T MRI of the ankle. Six axial, sagittal and coronal intermediate-weighted (IW) and fat-saturated T2-weighted (T2FS) 2D TSE (total acquisition time, 20 min), and two sagittal isotropic IW and T2FS 3D CAIPIRINHA TSE (10 min) pulse sequence prototypes were obtained.

Flexible Adult Acquired Flatfoot Deformity: Comparison Between Weight-Bearing and Non-Weight-Bearing Measurements Using Cone-Beam Computed Tomography.

Background: The 3-dimensional nature of adult acquired flatfoot deformity can be challenging to characterize using radiographs. We tested the hypothesis that measurements on weight-bearing (WB) cone-beam computed tomography (CT) images were more useful for demonstrating the severity of the deformity than non-weight-bearing (NWB) measurements.

Methods: We prospectively enrolled 12 men and 8 women (mean age, 52 years; range, 20 to 88 years) with flexible adult acquired flatfoot deformity.

Diagnosis and Characterization of Patellofemoral Instability: Review of Available Imaging Modalities.

Patellofemoral instability (PI) is defined as single or multiple episodes of patellar dislocation. Imaging modalities are useful for characterization of patellar malalignment, maltracking, underlying morphologic abnormalities, and stabilizing soft-tissue injuries. Using these findings, orthopedic surgeons can decide when to operate, determine the best operation, and measure degree of correction postoperatively in PI patients.

Simultaneous Multislice Accelerated Turbo Spin Echo Magnetic Resonance Imaging: Comparison and Combination With In-Plane Parallel Imaging Acceleration for High-Resolution Magnetic Resonance Imaging of the Knee.

Purpose: We prospectively quantified the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of integrated parallel acquisition technique (PAT) and simultaneous multislice (SMS) acceleration and various combinations thereof, and we further compared two 4-fold-accelerated (PAT2-SMS2) high-resolution turbo spin echo (TSE) magnetic resonance imaging (MRI) protocols of the knee against a clinical 2-fold-accelerated (PAT2-SMS1) TSE standard.

Materials And Methods: Institutional review board approval was obtained, and all subjects gave informed consent. Fourteen knee MRI examinations were obtained (8 men, 6 women; mean age, 46 years; age range, 28-62 years) using a 3 T MRI system and a TSE pulse sequence prototype that allowed for the combination of PAT and SMS acceleration.

MRI-guided cryoablation of the posterior femoral cutaneous nerve for the treatment of neuropathy-mediated sitting pain.

Neuropathy of the posterior femoral cutaneous nerve may manifest as pain and paresthesia in the skin over the inferior buttocks, posterior thigh, and popliteal region. Current treatment options include physical and oral pain therapy, perineural injections, and surgical neurectomy. Perineural steroid injections may provide short-term pain relief; however, to our knowledge, there is currently no minimally invasive denervation procedure for sustained pain relief that could serve as an alternative to surgical neurectomy.

Image quality of cone beam computed tomography for evaluation of extremity fractures in the presence of metal hardware: visual grading characteristics analysis.

Objective: To evaluate image quality and interobserver reliability of a novel cone-beam CT (CBCT) scanner in comparison with plain radiography for assessment of fracture healing in the presence of metal hardware.

Methods: In this prospective institutional review board-approved Health Insurance Portability and Accountability Act of 1996-complaint study, written informed consent was obtained from 27 patients (10 females and 17 males; mean age 44 years, age range 21-83 years) with either upper or lower extremity fractures, and with metal hardware, who underwent CBCT scans and had a clinical radiograph of the affected part. Images were assessed by two independent observers for quality and interobserver reliability for seven visualization tasks.

3T magnetic resonance neurography of pudendal nerve with cadaveric dissection correlation.

Aim: To evaluate the pudendal nerve segments that could be identified on magnetic resonance neurography (MRN) before and after surgical marking of different nerve segments.

Methods: The hypothesis for this study was that pudendal nerve and its branches would be more easily seen after the surgical nerve marking. Institutional board approval was obtained.

Compressed Sensing SEMAC: 8-fold Accelerated High Resolution Metal Artifact Reduction MRI of Cobalt-Chromium Knee Arthroplasty Implants.

Objective: The aim of this study was to prospectively test the hypothesis that a compressed sensing-based slice encoding for metal artifact correction (SEMAC) turbo spin echo (TSE) pulse sequence prototype facilitates high-resolution metal artifact reduction magnetic resonance imaging (MRI) of cobalt-chromium knee arthroplasty implants within acquisition times of less than 5 minutes, thereby yielding better image quality than high-bandwidth (BW) TSE of similar length and similar image quality than lengthier SEMAC standard of reference pulse sequences.

Materials And Methods: This prospective study was approved by our institutional review board. Twenty asymptomatic subjects (12 men, 8 women; mean age, 56 years; age range, 44-82 years) with total knee arthroplasty implants underwent MRI of the knee using a commercially available, clinical 1.

Dual-energy computed tomography has limited sensitivity for non-tophaceous gout: a comparison study with tophaceous gout.

Background: Dual-energy computed tomography (DECT) is a new diagnostic tool for gout, but its sensitivity has not been established. Our goal was to assess the sensitivity of DECT for the detection of monosodium urate (MSU) deposits in non-tophaceous and tophaceous gout, both at the level of the patient and that of the individual joint or lesion.

Methods: DECT was performed on 11 patients with crystal-proven non-tophaceous gout and 10 with tophaceous gout and included both the upper and lower extremities in 20/21 patients.

Incremental value of magnetic resonance neurography of Lumbosacral plexus over non-contributory lumbar spine magnetic resonance imaging in radiculopathy: A prospective study.

Aim: To test the incremental value of 3T magnetic resonance neurography (MRN) in a series of unilateral radiculopathy patients with non-contributory magnetic resonance imaging (MRI).

Methods: Ten subjects (3 men, 7 women; mean age 54 year and range 22-74 year) with unilateral lumbar radiculopathy and with previous non-contributory lumbar spine MRI underwent lumbosacral (LS) plexus MRN over a period of one year. Lumbar spine MRI performed as part of the MRN LS protocol as well as bilateral L4-S1 nerves, sciatic, femoral and lateral femoral cutaneous nerves were evaluated in each subject for neuropathy findings on both anatomic (nerve signal, course and caliber alterations) and diffusion tensor imaging (DTI) tensor maps (nerve signal and caliber alterations).

Six-Fold Acceleration of High-Spatial Resolution 3D SPACE MRI of the Knee Through Incoherent k-Space Undersampling and Iterative Reconstruction-First Experience.

Purpose: The aim of this study was to prospectively test the hypothesis that 6-fold acceleration of a 3-dimensional (3D) turbo spin echo (TSE) magnetic resonance imaging (MRI) pulse sequence with k-space undersampling and iterative reconstruction is feasible for fast high spatial resolution MRI of the knee, while yielding similar image quality and diagnostic performance when compared with a conventional 2-dimensional (2D) TSE MRI standard.

Materials And Methods: The study was approved by the institutional review board. A 10-minute isotropic 3D TSE knee protocol consisting of accelerated intermediate-weighted (repetition time, 900 milliseconds; echo time, 29 milliseconds; voxel size, 0.

The Relationship Between Tibial Tuberosity-Trochlear Groove Distance and Abnormal Patellar Tracking in Patients With Unilateral Patellar Instability.

Purpose: To evaluate the role of tibial tuberosity-trochlear groove (TT-TG) distance in patellofemoral kinematics by retrospectively reviewing the dynamic computed tomography scans of patients with unilateral patellofemoral instability and comparing unstable and contralateral asymptomatic knees.

Methods: We reviewed all dynamic computed tomography scans obtained at one tertiary care hospital from 2008 through 2013 and identified 25 patients with a history of recurrent unilateral patellofemoral instability. During the scans, subjects performed active knee extension against gravity.

Impact of high resolution 3 tesla MR neurography (MRN) on diagnostic thinking and therapeutic patient management.

Objective: To evaluate the impact of magnetic resonance neurography (MRN) on diagnostic thinking and therapeutic choices in patients with suspected peripheral neuropathy.

Methods: IRB approval was obtained for this HIPAA-compliant study. Questionnaires were administered to six surgeons regarding the diagnosis and treatment in 85 patients suspected of having peripheral neuropathy, before (pretest) and after (posttest) MRN.

Extremity cone-beam CT for evaluation of medial tibiofemoral osteoarthritis: Initial experience in imaging of the weight-bearing and non-weight-bearing knee.

Purpose: To investigate differences in joint space width (JSW) and meniscal extrusion (ME) between non-weight bearing (NWB) and weight bearing (WB) examinations of knee joints with medial compartment osteoarthritis (OA) using a cone-beam CT (CBCT) extremity imaging system.

Materials And Methods: In this IRB approved prospective study, informed consent was obtained for 17 patients symptomatic for OA (11 F,6 M; 31-78 years, mean 56 years) and 18 asymptomatic controls (0 F,18 M; 29-48 years, mean 38.5 years) enrolled for CBCT exams in NWB and WB positions.

Imaging characteristics of contralateral asymptomatic patellofemoral joints in patients with unilateral instability.

Purpose: To test the hypothesis that in patients with unilateral patellofemoral instability ( PI patellofemoral instability ), the contralateral asymptomatic joints have abnormal morphology and imaging features of osteoarthritis ( OA osteoarthritis ) at four-dimensional ( 4D four-dimensional ) computed tomography (CT).

Materials And Methods: The institutional review board approved this HIPAA-compliant retrospective study. Informed consent was waived.

Dynamic evaluation of pisotriquetral instability using 4-dimensional computed tomography.

The authors described 2 cases of pisotriquetral instability, which were diagnosed in patients presenting with ulnar wrist clicking and pain. The diagnosis was made first using 4-dimensional computed tomography, which helped further interventions and management in both patients.